Artificial Eye For The Blind

Artificial Eye For The Blind from Vineeth Sundar

1. ARTIFICIAL EYE
2.  Introduction  Components required  Working of artificial vision  Another approach to this  Advantages and disadvantages  Future scope  Conclusion
3. INTRODUCTION • There are 10 billion people in the US who are blind or facing blindness due to diseases of the retina… and there’s little that can be done for them. • For the vast majority, their best hope is through prosthetic devices. • The U.S. Food and Drug Administration (FDA) has market approval to an artificial retina technology, the first bionic eye to be approved for patients in the U.S.
4. Continued… • Scientists claim to have developed a new revolutionary bionic eye that enables blind people to read letters and simple words. • In the mid-20th century, researchers began to explore the idea of creating an artificial eye which could actually see.
5. ARTIFICIAL EYE? • An artificial eye is a prosthesis which is used to replace a missing or damaged eye. • In order to accomplish the goal of creating a visual prosthesis, scientists had to develop a camera which could interact with the brain by stimulating the optic nerve.
6. What happens when we look at an object?  Scattered light from the object enters through the cornea.  The light is projected onto the retina.  The retina sends messages to the brain through the optic nerve.  The brain interprets what the object is.
7. HOW BRAIN WORKS AFTER SEEING AN IMAGE? • After seeing an image the brain takes information from the outside world and encodes it in patterns of electrical activity. • After the creating pattern the brain get an visualization of an image. That can we actually seeing the image from our eyes.
8. Continued…. • In damaged or dysfunctional retina, the photoreceptors stop working, causing blindness • The absence of effective therapeutic remedies for retinitis pigmentosa (RP) and age-related macular degeneration (AMD)
9. ARGUS-II DEVICE  The Argus II Retinal Prosthesis System (“Argus II”) is the world’s first approved device intended to restore some functional vision for people suffering from blindness. transmits images from a small, eye-glass- mounted camera wirelessly to a microelectrode array implanted on a patient’s damaged retina.
10. Artificial silicon retina • Tiny device of diameter 2mm • Thinner than human hair • ASR implantations are two types • Epiretinal and subretinal
11. PARTS OF ARGUS II DEVICE The System has three parts: • a small electronic device implanted in and around the eye, • a tiny video camera attached to a pair of glasses, • and a video processing unit that is worn or carried by the patient.
12. Digital Camera • The camera used for this is the CMOS image sensor. • The camera captures the image and converts it into pixels of black and white. • This camera is placed on the goggles. • The battery required for this is provided from the video processing unit.
13. Video Processing Unit • Video Processing Unit acts as a optogenic transducer unit which simplifies the image as spots of light and then reduces the image to the number of photodiodes. • This is connected to goggles through router. • This unit majorly consists of • Video decoder • Video scalar • DSP processor • Video processor
14. Retinal implant • Electrode implantation is one of the most critical jobs in this artificial vision system • The first step done in this electrode implantation is perforating a platinum foil with each hole having a diameter of 3mm • 68 flat platinum electrodes of 1mm diameter are pierced through the holes into the nucleus of neurons of the occipital lobe
15. Continued……. • Each electrode is connected by separate Teflon insulated wire to a connector contained in the pedestal • The group of wires pass the electrical impulses which are generated by the processor • When the electrode is stimulated by the processor by sending an electrical impulse, the electrode produces closely spaced phosphene (light spots seen by visual field) • By sending the electrical impulses in different combinations and permutations the phosphene can be created in a regular fashion describing the image
16. Video Camera Video processing unit Receiver Retinal ImplantNeuronsBrains
17. Normal vision- Begins when light enters and strike on photoreceptor cells. These cells convert light to electric impulses that are sent to brain via optic nerves. Artificial vision- The camera captures images and sends to retina implant. It stimulates neurons. The stimulated neurons send information to brain via optic nerves.
18. When is it used? • The Argus II Retinal Prosthesis System is intended for patients aged 25 years • and older with bare or no light perception vision caused by advanced retinitis pigmentosa.
19. RESULTS OF THIS SYTEM • identify the location or movement of objects and people; • recognize large letters, words, or Sentences. • and helped in other activities of daily life, such as detecting street curbs and walking on a sidewalk without stepping off.
20. Support for Argus ii device… • Three government organizations provided support for the development of the Argus II. The Department of Energy, National Eye Institute at the National Institutes of Health and the National Science Foundation collaborated to provide grant funding totaling more than $100 million, support for material design and other basic research for the project.
21. Another approach to Artificial vision
22. Advantages • ability to perform visual tasks demonstrated in many patients • Upgradable external hardware and software to benefit from future innovations • the brain has an amazing ability to adapt to new input and to improve his or her understanding of what is being “seen” via an artificial vision system.
23. Disadvantages • The cost of device is too high( $1500) • It is difficult to acquire this technology by common man.
24. •Using ULSI technologies, the device can be further reduced in size
25. CONCLUSION

Artificial eye (Prosthetic Eye) advantages and disadvantages

Prosthetic eye can’t re-establish vision. After the evacuation of the natural eye and position of a prosthetic eye, a man will have no vision in that eye. Here are some advantages that you might from the prosthetic eyes.

Apposite Facial Function

One more favorable benefit of a prosthetic eye is that it gives our body a chance to work. For example, after losing an eye if an artificial eye is not immediately settled, the eye socket might begin shutting, and the eyelid should get drained and quit working properly.
Getting an artificial eye settled set up gives the eye socket a chance to keep hold of its great shape and size. Besides, it additionally gives the eyelid the opportunity to work precisely.

Improving Physical Appearance

Individuals who are feeling the loss of an eye or both don’t feel good continually wearing a bandage. There are very few alternatives for people with this handicap unless they pick a prosthetic eye.
Luckily, people may have prosthetic eyes hand -crafted by an ocularist that has some expertise in making artificial eyes. Prosthetic eyes are made out of acrylic. During the time spent in making the artificial eye, the iris is hand-painted and made as per the eye of the new owner.

Working up a Better Personality

A few people choose to have an artificial eye to show signs of improving their identity and to be resembling whatever is left of the world. It is not agreeable for many people to demonstrate their inability in the general population, given the look and inconsiderate questions stranger ask to them.

Boosting up Confidence

Having a prosthetic eye that shows up precisely like the other eye indeed builds a person’s confidence since they at no time in the future seem to have an inability. The artificial eyes help to boost up the confidence of the people who don’t have an eye.

A Beautiful Facial Look

The prosthetic eyes, give a person much beautiful look. It increases the attractiveness of the face.

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Contracted eye socket reconstruction

Contracted eye socket reconstruction from Mohammed Aljodah

1. CONTRACTED EYE SOCKET RECONSTRUCTION
2. Questions to be answered • What is the eye socket? • What is the common causes for enucleation? • What is the contracture of socket? • What cause that? • how to prevent it? • Aims of surgery? • Types of surgery? • Types of implant?
3. • Enucleation is the removal of the eye that leaves the eye muscles and remaining orbital contents intact. • Exenteration – removal of the contents of the eye socket, including the eyeball, fat, muscles, and other adjacent structures of the eye.
4. • Tenon's capsule thin membrane which envelops the eyeball from the optic nerve to the limbus, separating it from the orbital fat and forming a socket in which it moves, In front it adheres to the conjunctiva. • After enucleation orbital implant iserted to the Tenon's capsule in order to keep the orbital size and to keep eye animation .
5. The term Eye socket is refer to: • Eyelids • Conjunctival fornices • Orbital structures(bony cavity and soft tissues)
6. Common causes requiring socket reconstruction • Congenital (anophthalmia ,microphthalmia) • Trauma • Tumour • scarring
7. contracture of socket It refer to : • extensive loss of conjunctiva surface area • deep scar formation • shrinkage of orbital fat • conjunctiva fornices contracture.
8. Causes of contracture of socket • irradiation of the socket as after enucleation in some cases of retinoblastoma. • severe socket infections. • faulty or non wearing of the artificial eye. • keloid like mass formation in the socket. • tissue loss due to injury. • scarring of the conjunctiva due to various factors(allergy for ex.)
9. Main compliants The main presenting complaint : • story of a gradually increasing difficulty in retaining the prostheses. • the patients are not satisfied with the cosmetic appearance.
10. Preoperative assessment the contracted sockets should be examined clinically and microbiologically. History :In every case, mode, circumstances and duration of the eye loss, and subsequent problems with the prostheses . The socket should be examined for fibrous bands, condition of the various fornices and the state of the conjunctiva.
11. • Never forget to Assess the prosthesis shape and size . • Look for orbital implant exposure.
12. Grades of contracted sockets. • The soft tissue sockets were divided into five grades for the sake of convenience in management of contracted sockets. Grade-0: Socket is lined with the healthy conjunctiva and has deep and well formed fornices. Grade-I: Socket is characterized by the shallow lower fornix or shelving of the lower fornix. Here the lower fornix is converted into a downwards sloping shelf which pushes the lower lid down and out, preventing retention of a artificial eye
13. • Frequently there is shallow lower fornix and deep upper fornix resulting in upward migration of the prosthesis.
14. Grade-II: Socket is characterized by the loss of the upper and lower fornices
15. Grade- III: Socket is characterized by the loss of the upper, lower, medial and lateral fornices
16. Grade-IV: Socket is characterized by the loss of all the fornices, and reduction of palpebral aperture in horizontal and vertical dimensions
17. Grade-V: In some cases, there is recur- rence of contracture of the socket after repeated trial of reconstruction
18. Aims of reconstruction • To establish stable fornices by increasing the surface area by (hard palate ,oral mucosal,skin graft) and if necessary by increasing size by orbital implant. • The ocular prostheses should be light and take its support from infraorbital rim not from the lids.
19. Prevention • By use of conformer made by ocularist placed inside orbit to help support the growth of eye socket and bones in the face. • the conformer used during healing for about 6 weeks then ocular shell prosthesis used there after.
20. Types of ocular prosthesis • Spherical or oval • Stock or custom made • Porous or non porous • Chemical make up • Presence or absence of motility post.
21. Surgical principle • First : obtain adequate palpepral aperture size (canthoplasty may be needed in grade3,4,5) • Second : create adequate fornixes (lower,upper,lateral) insicion central in grade 2 while it can be at inferior position in grade 1. • Third : perfect lining of the created fornix (hard palate ,oral mucosal,skin graft ,amniotic membrane) • Fourth be sure that the fornix created supported by orbital bony rim to create a stable and deep lower fornix, the lower edge of the graft should be sutured to the inferior orbital bone rim using anchor sutures .
22. • Fifth: the conformer used during healing for about 6 weeks then ocular shell prosthesis used there after. • Sixth : central temporary tarsorrhaphy may be used.
23. Orbital implant exposure • One of the most important aspect of eye socket reconstruction can present with or without socket contracture.
24. Orbital implant exposure
25. • Autogenous Derma-Fat Graft used usally in case of Exenteration and in cases of extrusion or implant exposure.
26. The extraocular muscles and conjunctiva is sutured into the border of the DFG

Artificial eye advantages and disadvantages

An artificial eye is a replacement for a natural eye lost because of injury or disease. ... This material had the advantage of being unbreakable as well as malleable. ... Called stock eyes, they have the disadvantage of not being properly fitted

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Orbital implant

Orbital implants from samialbdairat

Orbital implants
1. SAMI AL-BDAIRAT, MD ORBITAL IMPLANTS
2. ANOPHTHALMIA • Anophthalmia is absence of globe • Congenital or acquired
3. ACQUIRED ANOPHTHALMOS • After enucleation/evisceration/exenteration
4. enucleation, evisceration, or secondary implantation surgery Conformer is placed in the conjunctival fornices to maintain the conjunctival space conformer is replaced with a custom-made ocular prosthesis typically fashioned 4–6 weeks
5. ANOPHTHALMIC SURGERY • Successful anophthalmic surgery is achieved when the anophthalmic patient obtains a painless, non-inflamed eye socket with adequate volume restoration and an artificial eye that looks and moves almost as naturally as a normal eye. • The optimal time to achieve the best functional and cosmetic result for the anophthalmic patient is at the time of enucleation
6. • orbital implant is typically placed at the time of evisceration or enucleation • ocular prosthesis is fitted subsequently.
7. DISPOSABLE SIZING KIT
8. ORBITAL SPHERE INTRODUCER Stainless Steel
9. CONFORMERS Translucent, Polyamide 12 Small 20mm Medium 23mm Large 26mm
10. • Anophthalmic implant: Material or substance used to replace an enucleated or eviscerated globe (e.g. polymethylmethacrylate, silicone,hydroxyapatite, aluminum oxide, porous polyethylene, etc.) • Porous implant: Refers to an implant with numerous interconnected pores or channels throughout its structure that permit fibrovascular ingrowth (e.g. hydroxyapatite, aluminum oxide, porous polyethylene) • Nonporous implant: Refers to an implant that is solid and does not allow fibrovascular ingrowth (e.g. polymethylmethacrylate, silicone)
11. • Buried implant: an implant that has been placed within the anophthalmic socket with an overlying closed, smooth, uninterrupted conjunctival surface completely covering the anophthalmic implant • Exposed implant: an implant that does not have an overlying closed, smooth, uninterrupted surface completely covering it. An exposed implant is an unwanted complication postoperatively with any implant
12. • Integrated implant: an implant that can be directly coupled to the overlying prosthetic eye with a peg system. As there is a small break in the overlying conjunctiva through which the peg protrudes, there is some debate whether this type of implant should also be known as a partially “exposed integrated implant • Non-integrated implant An implant that has been placed within the anophthalmic socket that has no connection with the overlying prosthetic eye. There is a closed, smooth, uninterrupted conjunctival surface completely covering the anophthalmic implant. Also known as a “buried non-integrated implant”
13. Peg: A motility coupling post, made of titanium, which permits direct coupling of the implant movement to an overlying prosthesis. Pegs may be inserted within sleeves that are drilled into the anterior aspect of the implant.
14. QUASI-INTEGRATED IMPLANT • An implant that has been placed within the anophthalmic socket with a closed, uninterrupted conjunctival surface completely covering an anophthalmic implant that has an irregular anterior surface, allowing indirect coupling (“quasi-integration”) of implant to overlying, modified prosthesis (e.g., Allen, Iowa, Universal, MEDPOR Quad implants). Also known as a “buried integrated implant” or an “indirectly integrated implant.” Recently designed magnetic coupling systems may also be classified as quasi- integrated .
15. ADVANTAGES OF EVISCERATION OVER ENUCLEATION • Less disruption of orbital anatomy. • Good motility of prosthesis • Lower rate of migration ,extrusion , reoperation.
16. HISTORY • As early as 500 B.C., Egyptians and Romans wore ocular prostheses (made of clay) designed by pagan priests. • Johannes Lange in 1555 (Lowenberg, Germany) was the first to mention enucleation (or extirpation as it was called then), no details of the operative procedure were given • George Bartisch, in 1583 the first recorded description of removal of an eye for treatment of severe ocular disease(Extirpation)
17. EXTIRPATION METHOD OF BARTISCH
18. HISTORY • Ambroise Pare in 1579 described the first prosthesis which was made of metal and coated with paint . • In 1841 current enucleation technique was established in separate reports (only weeks apart) by O’Ferrall (Dublin) and Bonnet (Paris) • The first recorded evisceration is credited to James Bear in 1817. • The first to perform a routine evisceration procedure was Noyes who, in 1874
19. HISTORY • In 1884, P.H. Mules developed a unique technique for evisceration, which has proved to be a milestone in ophthalmic surgery. He was the first to insert a hollow glass sphere (the “Mules” sphere) into the scleral cavity after removal of the cornea and intraocular contents • Since then Sponge, rubber, paraffin, ivory, wool, cork, cartilage, fat, bone, Vitallium, platinum, aluminum, silver, and gold were used as implant. • By the 1950s, A variety of implant designs were tried with an attempt to indirectly couple the buried implant to an overlying artificial eye by modifying the anterior surface of the implant as well as the posterior surface of the prosthesis. The Allen and subsequently the Iowa enucleation implants were buried integrated ( “quasi- integrated”) implants.
20. HISTORY • Troutman, Uribe, Iliff, magnetic implants – 1950s and 1960s), • Universal implant (1987) • By 1989, spherical implants made of silicone, glass, or polymethylmethacrylate (PMMA) were the implants most widely used by ophthalmic plastic surgeons • The introduction of coralline hydroxyapatite orbital implants in the mid- to late 1980s in enucleation, evisceration, or secondary orbital implant surgery ushered in a new era in anophthalmic socket reconstruction. • Several other porous implant materials have since been introduced as alternatives (e.g. synthetic hydroxyapatite, porous polyethylene, aluminum oxide).
21. IDEAL ANOPHTHALMIC SOCKET 1.A centrally placed, well-covered, buried implant of adequate volume, fabricated from a bio-inert material 2. A socket lined with healthy conjunctiva and fornices deep enough to retain a prosthesis and to permit horizontal and vertical excursion of an artificial eye 3. Eyelids with normal position and appearance, as well as adequate tone to support a prosthesis 4. A supratarsal eyelid fold that is symmetric with the supratarsal fold of the contralateral eyelid 5. Normal position of the eyelashes and eyelid margin 6. Good transmission of motility from the implant to the overlying prosthesis 7. A comfortable ocular prosthesis that looks similar to the sighted, contralateral globe and in the same horizontal plane
22. IDEAL ORBITAL IMPLANT • Maintain Natural Lid Shape : ability to receive a motility/support peg, to support the weight of the artificial eye to prevent lower lid laxity and malposition over time . • Light Weight • Porosity: The implant must allow vascular orbital tissues to invade its structure to: a) lock it into place and prevent migration, b) allow it to fight infections from within the implant via the vascular bed infiltrating the implant, and c) support "healing from within" of any defect in the conjunctival-Tenon's closure • True Integration The implant must be directly integrated (e.g., via a peg) with the artificial eye to allow direct transfer of all available movement from the rectus muscles to the artificial eye • Natural Biocompatibility: the implant must be a natural material and readily accepted by the tissues of the orbit to prevent "synthetic implant syndrome" i.e., pseudocapsule formation around the implant. This pseudocapsule is the body's way of walling off a foreign material • Non toxic non allergic
23. CURRENT CLASSIFICATION OF IMPLANTS • porous or nonporous, and in either category, the implants are non-integrated, integrated, or quasi- integrated • Porous implants (hydroxyapatite, porous polyethylene, aluminum oxide) • nonporous implants (silicone,polymethylmethacrylate) • Quasi integrated (or indirectly integrated) implants may be porous or nonporous and, because of their irregular anterior surface, are partially coupled to the overlying prosthetic eye (e.g., Allen, Iowa, Universal, MEDPOR ® Quad implant).
24. • non porous Inert spherical implants • Acrylic sphere • is the most basic implant. • Acrylic, or methylmethacrylate, • non-porous material • is best used in cases of trauma, such as a severe gunshot wound to the orbit • silicone sphere. This non-porous implant is similar to an acrylic implant, but slightly more pliable.
25. NON POROUS INERT SPHERICAL IMPLANTS Advantages • Provide comfort and low rates of extrusion. • Cost-effective choice in patients. Disadvantages • decreased motility and implant migration.
26. POROUS ORBITAL IMPLANTS hydroxyapatite • Perry (1985) introduced coralline (sea coral)(HA) spheres • complex calcium phosphate • regular and complete system of interconnecting pores ( 500- µm pore size ) • secure attachment of the extra ocular muscles • The most suitable for peg–sleeve system. •
27. hydroxyapatite Disadvantages: surface is abrasive Conjonctival thining extrusion or exposure infection. pyogenic granuloma formation, Costy Synthetic HA implants developed by FCI Chinese HA Brazilian HA Less expensive Poor porous structure
28. SYNTHETIC POROUS POLYETHYLENE (MEDPOR) • a porous type of plastic • Less biocompatible than HA • Well tolerated by orbital soft tissue • The surface is nonabrasive so extrusion is rare. They may be used with or without a wrapping material • extra ocular muscles can be sutured directly onto the implant
29. SYNTHETIC POROUS POLYETHYLENE (MEDPOR) • available in spherical, egg, conical, and mounded shapes (MEDPOR ® Quad implant) • The anterior surface can also be manufactured with a smooth, nonporous surface to prevent abrasion of the overlying tissue (e.g., MEDPOR ® smooth surface tunnel implant – SST™.
30. ALUMINUM OXIDE (AL 2 O 3, ALUMINA, BIOCERAMIC IMPLANT • porous, inert substance • permit host fibrovascular ingrowth • Human fibroblasts and osteoblasts proliferate more rapidly on aluminum oxide than HA suggesting it is a more biocompatible substance than HA • lightweight and has a uniform pore structure and excellent pore interconnectivity • The microcrystalline structure is smoother than the rough surfaced Bio-Eye • A protein coating that forms after insertion prevents the implant from being recognized as a foreign body This inert nature of these implants is a potentially critical advantage in minimizing socket inflammation. • Less expensive
31. VARIETY OF SHAPES Mesh-Wrapped Egg-Shaped Spherical
32. ADVANTAGES OF VICRYL MESH WRAP  Facilitates entry into the orbit by decreasing drag on surrounding structures  Allows suturing directly to implant  Eliminates need for donor tissue  No risk of disease transmission  Eliminates second surgical site  Absorbable  Allows 360 degree entry of fibrovascular tissue (as opposed to entry through scleral windows)
33. PEGGING • Is an option of any of the porous implants, most commonly done with hydroxyapatite. • The thought behind pegging is that it improves motility by allowing the pegged surface to fit into a corresponding groove in the back of the prosthesis . • can promote infection and lead to extrusion
34. DERMIS FAT GRAFT
35. ORBITAL IMPLANT SELECTION IN ADULTS • spherical versus shaped implants, wrapped versus unwrapped implants, and pegged versus unpegged implants. • In a 2004 survey of orbital surgeons, of 1,919 primary orbital implants used following enucleation, porous polyethylene was used in 42.7% of cases followed bycoralline HA (27.3%), nonporous alloplastic (PMMA, silicone) implants (19.9%), dermis-fat grafts (7.2%), Bioceramic (1.8%), synthetic HA (0.9%), and mammalian bone (0.2%)
36. ORBITAL IMPLANT SELECTION IN ADULTS • porous implant between the ages of 15 and 65 years old • quasi-integrated implant such as the Universal (PMMA – mounded) or MEDPOR ® Quad implant (mounded) • A nonporous sphere (e.g., PMMA, silicone), wrapped, centered within the muscle cone, and attached to each of the rectus muscles and inferior oblique muscle, • A nonporous implant simply placed into the orbit, without a wrap and without connection to the rectus muscles ……seventh decade or beyond),
37. ORBITAL IMPLANT SELECTION IN CHILDREN • less than 5 years age …..wrapped nonporous sphere implant 16- or 18-mm diameter Exchange with porous and bigger size is possible….autogenous dermis-fat grafts. • 5 to 15 years age ,nonporous implants, either a PMMA mounded implant (e.g. Universal) or a wrapped sphere (e.g. PMMA, silicone).
38. EXPOSURE AND EXTRUSION OF IMPLANT predisposing Factors  1. closing the wound under tension 2. poor wound closure techniques 3. Infection 4. mechanical or inflammatory irritation from the speculated surface of the porous implant 5. Delayed ingrowth of fibrovascular tissue with subsequent tissue breakdown
39. Preventive measures for implant exposure • proper placement of the implant within the orbit followed by a two-layered closure of anterior Tenon’s capsule and conjunctiva • Treatment : If few weeks, • No infection ,simple reclosure or with a patch graft (e.G., Sclera, temporalis fascia) is required • If infection is suspected and treated vigorously with topical and systemic antibiotics, an extrusion and removal of the implant may be avoided.
40. beyond 4–6 months, • If non porous implant, The defect should not be closed, and secondary orbital implant surgery should be arranged • If porous, exposure <3mm >3mm Treat conservatively Wait 8 weeks for spontaneous closure no Close with scleral patch graft surgical repair is indicated Using sclera patch graft or temporalis fascia patch graft
41. SUMMARY • Ophthalmic surgeons working closely with qualified ocularists must be focused on restoring a patient’s natural eye appearance with prosthetic motility as near normal as possible. • We currently prefer implantation of a porous implants, with or without polyglactin 910 mesh wrapp with attachment of all rectus muscles and inferior oblique to the covered implant. • Pegging may not be appropriate for all implant surgeons or anophthalmic patients. • We hope in the future….
42. THANK YOU

ORBITAL IMPLANTS

Orbital implants from Reshma Peter

1. ORBITAL IMPLANTS DR. RESHMA PETER
2.  Anophthalmia-Absence of globe  Defined as an orbit not containing an eye ball, but has orbital soft tissues  usually acquired, rarely congenital  The most common cause - enucleation of the globe
3. SURGICAL PROCEDURES IN THE REMOVAL OF AN EYE Classified into three categories Evisceration- Removal of the contents of the globe leaves the sclera ,fat,EOM, and other adjacent structures of the eye intact and sometimes the cornea in place. Enucleation- Removal of the eye leaves EOM and remaining orbital contents intact. Exenteration Removal of the entire contents of the orbit including EOM
4. Tenon's capsule-  Thin membrane which envelops the eyeball from the optic nerve to the limbus  Separates eyeball from the orbital fat  Forms a socket in which it moves  In front it adheres to the conjunctiva. After enucleation orbital implant inserted to the Tenon's capsule in order  to keep the orbital size  to keep eye animation
5. Eye socket Eyelids Conjunctival fornices Orbital structures(bony cavity and soft tissues)
6. Common causes requiring socket reconstruction  Congenital (anophthalmia ,microphthalmia)  Trauma  Tumour  scarring
7. Acquired anophthalmos After enucleation/evisceration/exenteration
8. Ideal anophthalmic socket 1.A centrally placed, well-covered, buried implant of adequate volume, fabricated from a bio-inert material 2. A socket lined with healthy conjunctiva and fornices deep enough to retain a prosthesis and to permit horizontal and vertical movements of an artificial eye 3. Eyelids with normal position ,appearance and adequate tone to support a prosthesis 4. A supratarsal eyelid fold that is symmetric with that of the C/l eyelid
9. 5. Normal position of the eyelashes and eyelid margin 6. Good transmission of motility from the implant to the overlying prosthesis 7. A comfortable ocular prosthesis that looks similar to the sighted, contralateral globe and in the same horizontal plane
10. Enucleation/evisceration secondary implantation surgery Conformer is placed in the conjunctival fornices to maintain the conjunctival space conformer is replaced with a custom-made ocular prosthesis typically fashioned 4–6 weeks ORBITAL IMPLANT CONFORMER OCULAR PROSTHESIS
11. Orbital implant typically placed at the time of evisceration or enucleation Ocular prosthesis fitted subsequently
12. Anophthalmic surgery Successful anophthalmic surgery is achieved when the anophthalmic patient obtains  a painless, non-inflamed eye socket  with adequate volume restoration  an artificial eye that looks and moves almost as naturally as a normal eye The optimal time to achieve the best functional and cosmetic result for the anophthalmic patient is at the time of enucleation
13. Most socket reconstructive surgeries are required to address the following problems: 1. A volume deficit following loss of the globe 2. Contracture of the socket 3. Orbital implant exposure, extrusion, and malposition
14. History  500 B.C.:Egyptians and Romans wore ocular prostheses  1555 :Johannes Lange (Lowenberg, Germany) 1st to mention enucleation (or extirpation as it was called then)  1583 :George Bartisch 1st recorded description of removal of an eye for treatment of severe ocular disease (Extirpation)
15. • 1579 :Ambroise Pare described the 1st prosthesis which was made of metal and coated with paint . • 1841: O’Ferrall (Dublin) and Bonnet (Paris) established current enucleation technique • 1817 :1st recorded evisceration by James Bear • 1874: Noyes -1st to perform a routine evisceration procedure •
16.  1884: P.H. Mules developed a unique technique for evisceration  a milestone in ophthalmic surgery  He inserted a hollow glass sphere (the “Mules” sphere) into the scleral cavity after removal of the cornea and intraocular contents Since then Sponge, rubber, paraffin, ivory, wool, cork, cartilage, fat, bone, Vitallium, platinum, aluminum, silver, and gold were used as implant.
17. 1886:Frost 1st described the placement of an orbital implant into an enucleated socket 1820s-1890s :Enamel prostheses introduced ;expensive and not durable.  1835 :Germans introduced cryolite glass  made of arsenic oxide and cryolite from NaAlF  grayish-white color suitable for a prosthetic eye  a tube of glass was heated on one end until the form of a ball obtained.  Various colors of glass used to imitate the natural eye color
18. • 19th century:German craftsmen ("ocularists") began to tour the US and other parts of the world, fabricated eyes and fit them to patients • Stock eyes (or pre-made eyes) were also utilized. An "eye doctor" might keep hundreds of glass stock eyes in cabinets, and would fit patients with the best eye right out of the drawer.
19.  After the onset of WW II, when German glass blowers no longer toured US,the US and practitioners developed prostheses using oil pigments and plastics. •1940 :Naval dental school used acrylic resin in fabricating a custom ocular prosthesis. The acrylic eye was •easy to fit and adjust •Unbreakable • inert to ocular fluids •aesthetical good •longer lasting •easier to fabricate
20. • 1950s:A variety of implant designs were tried with an attempt to indirectly couple the implant to an overlying artificial eye by modifying the anterior surface of the implant as as the posterior surface of the prosthesis. • The Allen and subsequently the Iowa enucleation implants were buried integrated ( integrated”) implants.
21.  1950s and 1960s :Troutman, Uribe, Iliff - magnetic implants  1987 :Universal implant  1989:spherical implants made of silicone, glass, or polymethylmethacrylate (PMMA)  mid- to late 1980s The introduction of coralline hydroxyapatite orbital implants in enucleation, evisceration, or secondary orbital implant surgery  Several other porous implant materials have since been introduced as alternatives (e.g. synthetic hydroxyapatite, porous polyethylene, aluminum oxide).
22.  Anophthalmic implant: Material or substance used to replace an enucleated or eviscerated globe (e.g. polymethylmethacrylate, silicone,hydroxyapatite, aluminum oxide, porous polyethylene, etc.)  Porous implant: Refers to an implant with numerous interconnected pores or channels throughout its structure that permit fibrovascular ingrowth (e.g. hydroxyapatite, aluminum oxide, porous polyethylene)  Nonporous implant: Refers to an implant that is solid and does not allow fibrovascular ingrowth (e.g. polymethylmethacrylate, silicone)
23.  Buried implant: an implant that has been placed within the anophthalmic socket with an overlying closed, smooth, uninterrupted conjunctival surface completely covering the anophthalmic implant  Exposed implant: an implant that does not have an overlying closed, smooth, uninterrupted surface completely covering it. An exposed implant is an unwanted complication postoperatively with any implant
24.  Integrated implant: an implant that can be directly coupled to the overlying prosthetic eye with a peg system. As there is a small break in the overlying conjunctiva through which the peg protrudes, Sometimes known as a partially exposed integrated implant  Non-integrated implant An implant that has been placed within the anophthalmic socket that has no connection with the overlying prosthetic eye. There is a closed, smooth, uninterrupted conjunctival surface completely covering the anophthalmic implant. Also known as a “buried non-integrated implant”
25. Peg: A motility coupling post, made of titanium, which permits direct coupling of the implant movement to an overlying prosthesis. Pegs may be inserted within sleeves that are drilled into the anterior aspect of the implant.
26. Quasi-integrated implant (buried integrated implant OR indirectly integrated implant) An implant that has been placed within the anophthalmic socket with a closed, uninterrupted conjunctival surface completely covering an anophthalmic implant that has an irregular anterior surface, allowing indirect coupling (“quasi-integration”) of implant to overlying, modified prosthesis (e.g., Allen, Iowa, Universal, MEDPOR Quad implants). Recently designed magnetic coupling systems may also be classified as quasi-integrated .
27. Integrated implants  designed to improve prosthesis motility by coupling to the overlying prosthesis.  Implant is exposed through the conjunctiva  directly coupled to the prosthesis with a peg, pin, screw or other method.
28. Semi-integrated ocular implants • consist of an acrylic resin implant with 4 protruding mounds on the anterior surface • These acrylic resin mounds protrude against the encapsulating tissue • The ocular prosthesis is made with a counter contour to the implant on the posterior surface of the prosthesis.
29. Nonintegrated implant done by placing a hollow or solid acrylic resin sphere ranging from 10 to 22mm in diameter.
30. Ideal orbital implant  Maintain Natural Lid Shape : ability to receive a motility/support peg, to support the weight of the artificial eye to prevent lower lid laxity and malposition over time .  Light Weight  Porosity: The implant must allow vascular orbital tissues to invade its structure to: a) lock it into place and prevent migration b) allow it to fight infections from within the implant via the vascular bed infiltrating the implant c) support "healing from within" of any defect in the conjunctival-Tenon's closure
31.  True Integration The implant must be directly integrated (e.g., via a peg) with the artificial eye to allow direct transfer of all available movement from the rectus muscles to the artificial eye  Natural Biocompatibility: the implant must be a natural material and readily accepted by the tissues of the orbit to prevent "synthetic implant syndrome" i.e., pseudocapsule formation around the implant. This pseudocapsule is the body's way of walling off a foreign material  Non toxic  non allergic
32. Current Classification of Implants porous or nonporous, and in either category, the implants are non-integrated, integrated, or quasi-integrated  Porous implants (hydroxyapatite, porous polyethylene, aluminum oxide)  Nonporous implants (silicone,polymethylmethacrylate) Quasi integrated (or indirectly integrated) implants may be porous or nonporous and, because of their irregular anterior surface, are partially coupled to the overlying prosthetic eye (e.g., Allen, Iowa, Universal, MEDPOR ® Quad implant).
33. Acrylic sphere  Acrylic, or methylmethacrylate  is the most basic implant  best used in cases of trauma, such as a severe gunshot wound to the orbit Silicone sphere  similar to an acrylic implant but slightly more pliable. Non porous inert spherical implants
34. Non porous inert spherical implants Advantages  Provide comfort and low rates of extrusion.  Cost-effective choice in patients. Disadvantages  decreased motility and implant migration.
35. Porous Orbital Implants Hydroxyapatite  Perry (1985) introduced coralline (sea coral)(HA) spheres  complex calcium phosphate  regular and complete system of interconnecting pores ( 500-µm pore size )  secure attachment of the extra ocular muscles  The most suitable for peg–sleeve system.
36. Disadvantages of HA:  Surface is abrasive  conjonctival thinning  Extrusion or exposure  infection  Pyogenic granuloma formation  Costly Synthetic HA implants developed by FCI Chinese HA Brazilian HA  Less expensive  Poor porous structure
37. Synthetic porous polyethylene (MEDPOR)  a porous type of plastic  Less biocompatible than HA  Well tolerated by orbital soft tissue  The surface is nonabrasive so extrusion is rare.  They may be used with or without a wrapping material  extra ocular muscles can be sutured directly onto the implant
38.  available in spherical, egg, conical, and mounded shapes (MEDPOR ® Quad implant)  The anterior surface can also be manufactured with a smooth, nonporous surface to prevent abrasion of the overlying tissue (e.g., MEDPOR ® smooth surface tunnel implant – SST™.
39. Aluminum oxide (Al 2 O 3, Alumina, Bioceramic implant)  porous, inert substance  permit host fibrovascular ingrowth  Human fibroblasts and osteoblasts proliferate more rapidly on aluminum oxide than HA suggesting it is a more biocompatible substance than HA  lightweight  has a uniform pore structure and excellent pore interconnectivity  The microcrystalline structure is smoother than the rough surfaced Bio-Eye  A protein coating that forms after insertion prevents the implant from being recognized as a foreign body This inert nature of these implants is a potentially critical advantage in minimizing socket inflammation.  Less expensive
40. Variety of Shapes Mesh- Spherical eggshaped
41. Advantages of vicryl mesh wrap  Facilitates entry into the orbit by decreasing drag on surrounding structures  Allows suturing directly to implant  Eliminates need for donor tissue  No risk of disease transmission  Eliminates second surgical site  Absorbable  Allows 360 degree entry of fibrovascular tissue (as opposed to entry through scleral windows)
42. Non integrated Semi integrated Fully integrated Expandable implants IMPLANTS
43. Pegging  Is an option of any of the porous implants, most commonly done with hydroxyapatite.  It improves motility by allowing the pegged surface to fit into a corresponding groove in the back of the prosthesis .  can promote infection and lead to extrusion
44. Orbital Implant Selection in Adults BETWEEN 15 AND 65 YEARS OLD  porous implant -quasi-integrated implant such as the Universal (PMMA – mounded) or MEDPOR ® Quad implant (mounded)  A nonporous sphere (e.g., PMMA, silicone), wrapped, centered within the muscle cone, and attached to each of the rectus muscles and inferior oblique muscle, SEVENTH DECADE OR BEYOND  A nonporous implant simply placed into the orbit, without a wrap and without connection to the rectus muscles
45. Orbital Implant Selection in Children LESS THAN 5 YEARS AGE  wrapped nonporous sphere implant 16- or 18-mm diameter  Exchange with porous and bigger size is possible  autogenous dermis-fat grafts 5 TO 15 YEARS AGE  nonporous implants, either a PMMA mounded implant (e.g. Universal) or a wrapped sphere (e.g. PMMA, silicone).
46. The orbital defect  The ideal defect is circumscribed fully by bony orbital rim.  The eyebrow should be intact.  The soft tissue defining the defect should be thin and immobile.  The surface with in the defect may be lined with a skin graft or even a free tissue flap.  may be the result of a congential anomaly (facial cleft), trauma (gunshot wound, road traffic accident) or surgery.
47.  Even with the advent of microscovascular surgery and free tissue transfers, surgical reconstruction alone cannot fully restore this area.  Prosthetic rehabilitation is needed.  If the defect is more extensive, bone and softissue grafting should be considered to missing portions of the orbital rim, zygoma, or temporal or midface regions before placement.  The surgical restoration of contour can contribute to a less extensive prosthesis.
48. Implant Placement  Implants are commonly placed in the orbital rim most often superiorly and laterally.  Placement in the inferior rim is desirable if the shape of the defect and access permit.  This improves the stability and retention of prosthesis.  In larger defects extending beyond the orbital rim, implants can be placed in the zygoma or maxilla.  Even a single implant can help stabilize and retain a prosthesis.
49. Surgical Positioner  Actual placement of the implants is guided by a surgical positioner.  This is an acrylic resin prototype of the prosthesis that is used intraoperatively.  It indicates the ideal position for implant placement.  It also serves as guide for selection of the retentive mechanism and later as a time saving reference for the shape of the prosthesis.  It helps determine if preprosthetic surgery is needed before implant placement.  Most often, the lateral superior aspect of the orbital rim needs reduction to place an implant at the location and remain with in guidelines of the positioner .
50.  Implant angulation should be parallel to the frontal plane of the face or be inward slightly.  A protrusive angulation can interfere with positioner contour and require compromise of the ideal shape of the prosthesis.  At the same time implant should not be over-angulated inward because prosthetic access for fabrication of retentive mechanism can be hampered.  This is true especially in smaller shallow defects when a soft-tissue flap has been used to close the opening of the defect.
51.  At second-stage surgery, the gauze strip surgical dressing should be wrapped carefully around the abutments and under the healing caps so that close adaptation of skin to the abutment and underlying bone is achieved.
52. TECHNIQUE OF IMPLANT INSERTION Soil described an improved surgical method of placing the orbital implant following the enucleation of the eye  The optic nerve and its associated vessels are severed and tied close to the posterior wall of the capsule.  The implant is placed deep within the muscle cone, and buried beneath the posterior layer of Tenon’s capsule  The posterior portion of Tenon’s capsule is closed over the implant providing the first layer of closure.
53.  Next, the anterior portion of Tenon’s capsule and conjunctiva are then closed to form the second and third layers over the implant.  The horizontal rectus muscles are then attached to the medial and lateral fornix.  It is the movement of the fornix in the enucleated socket that provides the motility to the artificial eye. For example, as a person looks up. the inferior fomix shortens, the superior fornix deepens and the prosthesis revolves upward
54.  By utilizing the posterior layer of Tenon’s capsule,a larger implant can be placed deep within the muscle cone which  decreases the incidence of implant migration  reduces the tension on the anterior Tenon’s capsule sutures  reduces the volume deficit in the superior and inferior sulcus preventing enophthalmos which can be produced by smaller implants Orbital Sphere Introducer
55.  Postoperative complications may develop during the first weeks following surgery.  Early extrusion of the implant may occur secondary to  orbital hematoma formation and infection  traumatic manipulation of the tissues  placement of too large an implant thus creating excess tension on Tenon’s capsule  The technique of wrapping the orbital implant with fresh or preserved scleral tissue is thought to be a deterrent for extrusion and migration of the implant and it is a technique used quite frequently with enucleation
56.  After enucleation. a plastic conformer and corticosieroid antibiotic ointment is placed in the socket.  The conformer should fit the contour of the socket and fill the depths of the fornices.  The conformer should not be removed by the patient, as it is designed with drainage holes  to allow mucoid discharge to escape  for insertion of postoperative medication  The plastic conformer is left in place for 4 to 6 weeks to reduce edema and maintain the socket contours by stretching the fornices for the prosthetic eye. SMALL MEDIUM LARGE 20mm 23mm 26mm
57. • Following healing of the anophthalmic socket, a stock or custom eye should be placed temporarily for cosmetic and psychological reasons. • Patient should be taught how to insert and remove the eye (devote separate time, quiet room and a mirror) • Patient should be encouraged to minimize handling the artificial eye. • Daily removal and cleaning is not necessary.
58. Notch is superonasally
59.  Lubrication may improve comfort (no tap water! Ringers, Saline or Artificial Tears may work well instead, packed in the eyedrops bottles)  There is only one eye now.  Encourage using the protective plastic glasses  One artificial eye should serve for 6-8 years.  Easily gets damaged while dropped down  Advise annual check up.
60. Evaluating the socket of anophthalmic patient: 1) Socket is fit or infmalmed? 2) Lower lid is healthy or lax? 3) Can the patient blink naturally? 4) Any lagophthalmos? 5) Are the fornices deep enough? 6) Giant papillae of upper tarsal conjunctiva?
61. Evaluating the prosthesis 1) Artificial eye is well centered? 2) Horizontal symmetry? 3) Equal prominence? 4) High gloss, wet shine? 5) Scratches, debris of the surface? 6) Moving naturally within 10-15 degrees?
62. Types of ocular prosthesis  Spherical or oval  Stock or custom made  Porous or non porous  Chemical make up  Presence or absence of motility post.
63. impression of the socket is taken Once the impression material sets to a firm consistency, the shape is copied into a wax mold prepared iris–cornea piece is positioned on the front surface of the wax pattern. mold is placed into the socket and modifi ed (reshaped) for comfort and to improve cosmesis The wax shape is then translated (using additional molds) into fine quality acrylic (from methyl methacrylate resin), painted, cured, and polished. Modified impression technique
64. Prosthesis
65. CRITERIA FOR SUCCESS OF CRANIOFACIAL OSSEOINTEGRATED IMPLANTS (According to “Swedish council on Technology assessment in Health care”)  Implants are immobile as verified by clinical examination.  No prolonged symptoms, such as pain, infection, tactile disorders or nerve damage should be present in connection with the implants.  Penetrated soft tissue should be free from irritation in at least 85% of regular out patient postoperative checks.  At least 95% of the temporal bone implants and at least 75% of other extraoral implants should be functional after 5 years.
66. PROSTHETIC TECHNIQUES: I) Fabrication of the ocular prosthesis:  Ocular prosthesis is made in conjunction with the surgical positioner because its shape and position relate to the overall shape of the orbital prosthesis.  A stock eye piece can be used. However, custom fabrication yields the best aesthetic results.  A pyramidal index of acrylic resin is incorporated on to the back surface of the eyepiece to aid in registering its position in the wax prototype and for subsequent mold making
67. II) Impression making: Impression making for an orbital prosthesis varies depending on the anatomic the orbital defect, location of implants and type of retention system selected daily hygiene procedures should be performed by the patient to maintain the health of the soft stabilization of the soft tissue to ensure fit and marginal adaptation of the prosthesis. This allows time for adequate healing Impression is made 8 – 12 weeks after of the abutments.
68.  If individual magnets are used for retention, the MAGNACAPs are threaded into the abutments, and the transfer magnets are placed on them.  These can be connected with autopolymerising resin to stablize them in impression.  The impression can be made using irreversible hydrocolloid, a silicone rubber .  The impression should include the entire midface to provide adequate references and landmarks for accurate sculpting
69.  Orientation lines are marked on the patient indelible pencil and will be transferred to the cast to aid this process.  After removal of the impression and disinfection, LAB-ANALOGUE CAPS are placed the transfer magnets and the impression is poured in dental stone.
70. III Design and Fabrication of resin plate  The resin plate retains the retentive components in a rigid base and provides stability for the prosthesis.  In most cases, it should be as small as possible so as not to interfere with the placement of the ocular prosthesis  Magnets are placed on the lab-analogue caps on the cast.  Wax is used to block out the defect and the abutments
71.  The resin engages this area to help retain the magnets in the plate.  The area is bordered with boxing wax, and clear autopolymerising acrylic resin is poured over the area, covering the magnets and engaging the retentive rim.  The thickness should be minimal and uniform to control distortion  A sprinkle on method can be used to apply the resin to better control the thickness of the plate.  Alternatively, colourless urethane dimethacrylate visible light cure resin can be used to fabricate the plate.  It is cured initially on the cast with a handheld light and then placed in the curing unit to complete curing.  The processed plate is shaped not to interfere with the ideal contour of the prosthesis. It is adjusted on cast and then tried on the patient. Complete engagement of retentive elements should be verified
72. IV Sculpting the wax prototype:  To achieve a life like orbital prosthesis, attention to anatomy and surface detail is important.  Input from the patient and family members is encouraged during this process.  To begin the sculpting process, the ocular prosthesis is attached to resin plate with utility wax while both are on the mastercast, using the orientation lines as a guide. When the prosthesis is transferred to the patient, depth, position, and gaze are evaluated relative to natural eye.
73. One or more of the following are helpful in creating the wax prototype : the patient tissue conforme r computeri zed images Surgical positioner photograp hs measuring devices (boley and contour gauges, calipers)
74. V Mold making:  A three – piece mold of white improved dental stone is made : tissue side, eyepiece and outer surface.  Once the wax prototype is completed, its outline is marked on the cast with indelible pencil .  An impression of the defect extending beyond the margins of the prosthesis is made with duplicating silicone elastomer and resin forced with plaster backing.  The periphery of this impression is poured in stone so that the center of the defect is left open.  Registration keys are placed in the tissue side of the mold.  Lab-analogues of magnetic caps are placed on the magnets with in the resin plate
75.  The wax prototype is seated back on the cast by using the transferred pencil line as guide for orientation, and the margins are sealed.  Skin surface detail can be refined at this time  Stone is poured into the back of the wax prototype through the opening of the cast .  Once set, wax spacers to facilitate later mold seperation are placed in the first piece of the mold, a seperator is applied to the stone surface, paper tape or wax is used to box the mold, and the top portion or outer surface of the mold is poured .  Once the stone has set, the mold is separated and the eyepiece and resin plate are removed. The mold is cleaned with boiling water and detergent to remove all wax residue
76.  Before casting the prosthesis, silicone elastomer is used to make a mold of the outer surface of the resin plate while it is in place of on the tissue side of the mold.  The impression material should be applied with a syringe around the edges to capture the ledge on the tissue side of the plate.  Then a two piece silicone mold is of the eyepiece and this is poured in stone.  This stone reproduction is used in the mold in place of resin eyepiece during processing to protect it from damage.  These steps allow the resin plate and prosthesis to be remade without the patient and the prosthesis present, when a replacement prosthesis is necessary.
77. Maintenance of Prosthesis  To maintain the health of the implants and surrounding soft tissue and to preserve the prosthesis and retention mechanism.  Bone anchored facial prosthesis require more care on the patient’s part and closer professional follow-up than one retained with adhesive.
78. HOME CARE AFTER ABUTMENT CONNECTION  Follow up management actually begins once the abutments have been placed.  After the initial healing period and once a surgical dressing is no longer needed, the patient should be instructed to clean this area on a daily basis  to remove cellular material on the skin or abutment, which can come from the interface of the epithelium and abutment.
79.  This is performed with a soft, end tuft nylon bristle toothbrush, an interproximal dental brush or a cotton swab.  The area should be moistened first with an even mixture of H2O2 and H2O to soften any dried debris  When checking abutment tightness, an abutment clamp should be placed on the abutment body to provide countertorque so that undue force is not placed on the implant.  If the abutment loosens, complete seating should be verified before retightening. This is done with an abutment holder.
80. HOME CARE AFTER PROSTHESIS PLACEMENT  On the day that the prosthesis is given to the patient,adequate time should be allotted for instructions on placing and removing the prosthesis as well as proper maintenance of the prosthesis, abutments, and surrounding skin areas.  patient should be careful when removing the prosthesis so that the thin margins do not tear and the silicone rubber does not separate from the resin plate  At night, the prosthesis should be removed and cleaned.  The patients should wash their hands first to decrease chances of soiling the prosthesis during handling.  All surfaces of the prosthesis should be cleaned gently with a soft, nylon-bristle toothbrush and mild soap and water
81.  The prosthesis should be patted dry with a towel and placed in a covered container.  Should be stored away from extreme heat or direct sunlight, which can cause degradation and discolouration of the prosthetic material.  The prosthesis should not be worn during sleep so that air can circulate around the abutments to help maintain skin health
82. Complications
83. Exposure and Extrusion of Implant  Implant exposure may occur with any type of implant or at any time  may lead to implant extrusion or explantation
84. Porous orbital implants have a lower incidence of implant exposure than traditional nonporous implants Predisposing factors  1. closing the wound under tension 2. poor wound closure techniques 3. Infection 4. mechanical or inflammatory irritation from the speculated surface of the porous implant 5. Delayed ingrowth of fibrovascular tissue with subsequent tissue breakdown
85. Preventive measures for implant exposure  proper placement of the implant within the orbit  two-layered closure of anterior Tenon’s capsule and conjunctiva Treatment : If few weeks,  No infection simple reclosure or with a patch graft (eg, Sclera, temporalis fascia)  If infection is suspected vigorous treatment with topical and systemic antibiotics an extrusion and removal of the implant may be avoided.
86. beyond 4–6 months,  If non porous  The defect should not be closed secondary orbital implant surgery should be arranged  If porous, exposure <3mm >3mm Treat conservatively Wait 8 weeks for spontaneous closure no Close with scleral patch graft surgical repair is indicated Using sclera patch graft or temporalis fascia patch graft
87. TREATMENT OF VOLUME DEFECIT
88. Dermis fat graft
89. TREATMENT OF LID LAXITY
90. Lax socket and inferior fornix shelving :  results from shifting of tissues within the orbit  With time there is involutional relaxation of the supporting tissues of the inferior eyelid  the weight and pressure effect of the prosthesis  laxity of the lid  inability to retain the prosthesis Treatment  Use prosthesis of optimal weight and size  Lateral tarsal strip  fornix formation sutures to increase the depth of inferior fornix
91. FORNIX DEEPENING SUTURES
92. Anophthalmic ptosis  Inadequate implant size  Migration of the orbital implant  Poorly fit prosthesis  Laxity of the fibrous connective tissue  Orbit trauma from the original injury/surgery  Senile dehiscence of the levator aponeurosis  Frequent manipulation of the eyelids to insert and remove the artificial eye also stretches the upper eyelid tissues  drooping eyelid.
93. Pseudoptosis  Due to the loss of volume between the implant and the lids after removal of the eye.  Occurs with a small, poorly fitted prostheses  If the physiological function of the eyelids is intact, correction of pseudoptosis is achieved by increasing the volume of the prosthesis in the socket.  A simple technique of correcting pseudoptosis is to make a larger prosthesis that will thrust forward and separate the eyelids
94. Treatment  Small amounts of ptosis may be managed by modification of the prosthesis  correction of socket volume deficiency should be considered prior to levator surgery  Once the other factors contributing to ptosis in the anophthalmic socket have been addressed tightening of the levator aponeurosis can be done
95. Treatment of enophthalmos :  placement of a secondary orbital implant if no implant was placed at the time of primary surgery  Dermis fat graft (DFG) is an option in patients with associated surface contracture  Orbital floor implants. Autologous bone grafts Non autologous medpor Treatment of superior sulcal deformity  implantation of fascia lata / sclera / bone / fat/ alloplastic material in upper eyelid
96. Anophthalmic ectropion  Frequently associated with significant lower eyelid laxity  A large or heavy prosthesis or frequent prosthesis removal may contribute to a stretching of the medial and/or lateral canthal tendons  Rotation of the orbital contents inferiorly and anteriorly contribute to a shallow inferior fornix, tilt of the prosthesis, and lower eyelid ectropion
97. Treatment  If the prosthesis is >5 years old, a new one may be required  If the prosthesis is large then a thinner or lighter prosthesis may help correct the malposition  Tightening the lateral or medial canthal tendon may remedy the situation  Correction of eyelid retraction by recession of IR/ grafting of mucus membrane tissue inferior fornix
98. Contracted socket  extensive loss of conjunctiva surface area  deep scar formation  shrinkage of orbital fat  conjunctiva fornices contracture.  the shrinkage and shortening of orbital tissues  decrease in depth of fornices and orbital volume  leading to inability to retain prosthesis. Guibor has classified clinically contracted socket into 4 morphological types
99. Causes Etiology related ・Alkali burns ・Radiation therapy Surgery related  Fibrosis from the initial injury  Poor surgical techniques during previous surgeries -enucleation /evisceration with extensive dissection of orbital tissue  Excessive sacrifice of the conjunctiva and tenons capsule  Traumatic dissection within the socket leading to scar tissue  Multiple socket operations
100. Site related  Poor vascular supply  Severe ischemic ocular disease in the past  Cicatrizing conjunctival diseases  Chronic inflammation and infection Implant and prosthesis related  Implant migration  Implant exposure  Not wearing a conformer/prosthesis  Ill fitting prosthesis
101. Grades of contracted sockets.  The soft tissue sockets were divided into five grades for the sake of convenience in management of contracted sockets. Grade-0: Socket is lined with the healthy conjunctiva and has deep and well formed fornices.
102. Grade-I: Shallow lower fornix or shelving of lower fornix Here the lower fornix is converted into a downwards sloping shelf which pushes the lower lid down and out, preventing retention of a artificial eye. shallow lower fornix and deep upper fornix resulting in upward migration of the prosthesis
103. Grade-II: Socket is characterized by the loss of the upper and lower fornices
104. Grade- III: Socket is characterized by the loss of the upper, lower, medial and lateral fornices
105. Grade-IV: Socket is characterized by the loss of all the fornices, and reduction of palpebral aperture in horizontal and vertical dimensions
106. Grade-V: In some cases, there is recurrence of contracture of the socket after repeated trial of reconstruction
107. Aims of reconstruction  To establish stable fornices by increasing the surface area by (hard palate ,oral mucosal,skin graft) and if necessary by increasing size by orbital implant.  The ocular prostheses should be light and take its support from infraorbital rim not from the lids.
108. Surgical principle  First : obtain adequate palpepral aperture size (canthoplasty may be needed in grade3,4,5)  Second : create adequate fornixes (lower,upper,lateral) insicion central in grade 2 while it can be at inferior position in grade 1.  Third : perfect lining of the created fornix (hard palate ,oral mucosal,skin graft ,amniotic membrane)
109.  Fourth be sure that the fornix created supported by orbital bony rim to create a stable and deep lower fornix, the lower edge of the graft should be sutured to the inferior orbital bone rim using anchor sutures .  Fifth: the conformer used during healing for about 6 weeks then ocular shell prosthesis used there after.  Sixth : central temporary tarsorrhaphy may be used.
110.  Bone anchored implant  offers increased security especially with large defects or where the prosthesis rests on highly mobile tissues.  Perspiration and vigorous physical activity will not affect the retention  Independence from reliance on adhesives frees the patient from tedious task of applying and removing adhesive at each application and removal of prosthesis.  It prolongs the life of prosthesis, as the edges are not subjected to excessive handling  Follow-up for the clinical evaluation of implant tissues and the maintenance and periodic replacement of the facial prosthesis are a must
111. REFERENCES  Clinical Maxillofacial Prosthetics-Thomas d. Taylor  Maxillo Facial Rehabilitation – Prosthodontic and surgical consideration -JOHN BEUMER  Prosthetic rehabilitation-Keith.F.Thomas  Ophthalmic and Plastic and Reconstructive Surgery
112. THANK YOU!!!

EVISCERATION, ENUCLEATION, EXENTRATION, CYCLODESTRUCTIVE PROCEDURES

EVISCERATION, ENUCLEATION, EXENTRATION, CYCLODESTRUCTIVE PROCEDURES from Reshma Peter

1. EVISCERATION ,ENUCLEATION ,EXENTRATION AND CYCLODESTRUCTIVE PROCEDURES Dr. Reshma Peter
2. SURGICAL PROCEDURES IN THE REMOVAL OF AN EYE Classified into three categories EVISCERATION Removal of the contents of the globe leaves the sclera ,fat,EOM, and other adjacent structures of the eye intact and sometimes the cornea in place. ENUCLEATION Removal of the eye leaves EOM and remaining orbital contents intact. EXENTERATION Removal of the entire contents of the orbit including EOM
3. EVISCERATION • A surgical technique by which all intraocular contents are removed • Scleral shell, EOM attachments, surrounding orbital adnexa preserved • The surgery often includes placement of an implant into the cavity to maintain appropriate orbital volume.
4. Indications • Panophthalmitis, Endophthalmitis • Penetrating ocular trauma • Blind, painful eye • Expulsive Choroidal haemmorhage • Bleeding Anterior Staphyloma
5. Contraindications • Known or suspected intraocular malignancy Relative Contraindications • Phthisis bulbi • Microphthalmia
6. • Careful pre-operative evaluation to ensure there is no intraocular malignancy in the operative eye • Performed under GA or in some cases, IV monitored sedation. • Retrobulbar anesthesia with epinephrine is often given to reduce intraoperative bleeding and postoperative pain.
7. Surgical Technique • A 360-degree conjunctival peritomy is then made at the limbus utilizing Wescott scissors undermine the conjunctiva and Tenon’s capsule • A full-thickness incision is then made at the limbus so that scissors may be introduced to excise the cornea in a circumferential manner. • All intraocular contents, including uveal tract, crystalline lens, vitreous humor, and retina are then removed by using an evisceration spoon, spatula, suction. • These contents are sent for histopathologic examination. • Sclera is swabbed with Absolute Alcohol to denature adherent uveal remnants and irrigated properly to remove alcohol
8. • Hemostasis of the nerve and vortex veins may then be achieved with cautery and direct pressure. • In some cases, a posterior sclerotomy or radial scleral relaxing incisions to allow for a larger implant to be placed. • The best implant size to restore orbital volume is selected while ensuring appropriate position. • Implant material is made of different materials like acrylic, PMMA, silicone, and hydroxyapatite. • The implant may be placed directly into the scleral shell
9. • The anterior sclera, Tenon’s capsule, and conjunctiva is then carefully closed in a layered approach before placement of a conformer. • Sclera is sutured with interrupted 6-0 Vicryl • • Conjunctiva with running mattress 6-0 Vicryl • A temporary tarsorrhaphy may be performed to help the conformer remain in place to maintain the fornices till prosthesis can be placed
10. • Perioperative antibiotics are often administered and are especially important in the setting of endophthalmitis. • A pressure patch may be applied and kept in place for approximately 5 days following surgery. • Ice cold compresses help with post-operative edema and comfort • Once the conjunctiva closure has healed, generally about 4-8 weeks postoperatively, patients are referred to an ocularist for fitting of an ocular prosthetic fitting.
11. 4-petal technique of Evisceration It has several advantages over the traditional evisceration technique. • allows placement of a larger implant • enables double-breasting of scleral cover • eliminates the need for a myo-conjunctival technique. • The vertical closure of the conjunctiva retains the depth of the lower fornix, which is of importance to retain the ocular prosthesis.
12. Frill evisceration Technique only 3mm frill of sclera is left around Optic Nerve • If a scleral buckle or glaucoma drainage device is present in the eviscerated eye, it should be removed. • If silicone oil is present within the eye, the limbus can be incised and the silicone oil irrigated from the eye prior to peritomy. • Evisceration with removal of cornea done for those with corneal sensation /pain or in CT disorders/ RA –chances of corneal thinning
13. Complications • Retrobulbar hemorrhage • Orbital edema • Dissemination of unexpected intraocular neoplasm • Extrusion of implant
14. Advantages of Evisceration over Enucleation 1. Shorter operative time 2. More cost efficient 3. A technically simpler procedure 4. A less invasive procedure (important in cases when GA is contraindicated or in bleeding disorders) 5. Less disruption of orbital tissues – chance of injury to EOM ,nerves and fat atrophy is reduced – Relationships between the muscles, globe, eyelids, and fornices remain undisturbed – Less chance of spread of infection to nervous system
15. 6. Less painful 7. Better cosmesis 8. Good motility of the prosthesis- EOM remain attached to the sclera 9.Lower rate of migration, extrusion, reoperation and socket complications 10.Preferred by some surgeons in cases of endophthalmitis as drainage of the ocular contents can be done without invasion of the orbit. • The chance of contamination of the orbit with orbital cellulitis or intracranial extension is therefore theoretically reduced.
16. Disadvantages of Evisceration over Enucleation • Risk of sympathetic ophthalmia • Risk of dissemination of intraocular tumors • Offers a less complete specimen for pathologic examinations. • Not every patient is a candidate. C/I if intraocular tumours are suspected and in Severe Pthisis
17. ENUCLEATION • A surgical procedure that involves removal of the entire globe and its contents. • all other periorbital and orbital structures including parts of EOM and orbital fat preserved.
18. Indications • Eye donation • Intraocular malignancy or high suspicion for intraocular malignancy (most commonly uveal melanoma and retinoblastoma) • Trauma • Blind, painful eye • Sympathetic ophthalmia • Microphthalmia • Phthisis bulbi • Endophthalmitis • Cosmetic deformity
19. • Performed under GA or LA • A retrobulbar block of local anesthetic with epinephrine is administered to aid in hemostasis and postoperative pain management. • Lateral canthotomy to get adequate space (especially in paediatric RB)
20. Surgical Technique • A 360 degrees limbal conjunctival peritomy is performed with Wescott scissors • Blunt dissection in the sub-Tenon's plane is then carried out in each of the oblique quadrants. • Each rectus muscle is then identified, isolated with a muscle hook, secured with double arm 6-0 vicryl suture, and cut at the insertion to the globe leaving an adequate stump with traction suture • The superior and inferior oblique muscles are isolated and transected. • Once the globe is determined to rotate freely, the optic nerve is identified, strummed, and cut with enucleation scissors or an enucleation snare wire.
21. • A long segment of the optic nerve is cut , particularly in intraocular malignancy for histologic examination. Curved scissors inserted orbital apex palpated with tip, withdraw slightly, confirm Optic N. which is severed with a single cut • Additional hemostasis achieved with direct pressure in the intraconal space and cautery of the optic nerve if needed. • Needles of double armed recti sutures passed through respective fornices and tied on ant surface of conjunctiva thus securing recti to fornix. • An implant is then placed in the intraconal space to replace volume lost, achieve cosmetic symmetry with the fellow socket, and allow for motility of the prosthesis. • To determine appropriate diameter of the implant, the formula axial length-2 mm has been shown to provide for adequate replacement of lost volume and minimize superior sulcus deformity and enophthalmos.
22. • In severe infection,implant is placed in a second surgery. • A two-layered closure with 6-0 vicryl is then carried out with absorbable sutures, first of tenon’s capsule (interrupted suture)and then of the conjunctiva(running mattress suture). • Antibiotic ointment is applied, a clear plastic conformer is placed over the closed conjunctiva • A pressure patch is placed over the socket. • Once the conjunctiva closure has healed,about 4-8 weeks postoperatively, patients are referred to an ocularist for fitting of an ocular prosthetic fitting. • Patients will require regular follow up with both an oculoplastic surgeon and an ocularist to maintain the health of their socket.
23. Advantages • Enucleation allows for histologic examination of an intact globe and optic nerve. • This is important in biopsy of proven or suspected intraocular malignancy, where it is essential to determine the margins of the malignancy and invasion of the optic nerve, if any. • Enucleation classically has been thought to decrease the risk of sympathetic ophthalmia as it avoids exposure to uveal antigens that may occur during an evisceration.
24. Disadvantages A reduction in implant motility is often noted in enucleation.
25. Complications Intraoperative • Removal of the wrong eye • Damage to or loss of extraocular muscles • Hemorrhage Postoperative • Infection • Hemorrhage • Wound dehiscence • Extrusion of the conformer • Contraction of the fornices • Exposure of the implant • Extrusion of the implant • Migration of the implant • Ptosis • Ectropion • Entropion • Hollow or deep superior sulcus • Poorly fitting prosthesis • Enophthalmos • Socket contracture • Orbital cellulitis
26. EXENTRATION • A surgical procedure involving removal of the entire globe and its surrounding structures including muscles, fat, nerves, and eyelids (extent determined by disease being treated) • The goal is to remove all lesions along with appropriate margins of adjacent tissue while retaining as much healthy tissue as possible. • The technique selected depends on the pathologic process.
27. Varieties of orbital exenteration Subtotal : The eye and adjacent intraorbital tissues are removed such that the lesion is locally excised (leaving the periorbita and part or all of the eyelids). This technique is used for some locally invasive tumors, for debulking of disseminated tumors, or for partial treatment in selected patients. Total: All intraorbital soft tissues, including periorbita, are removed, with or without the skin of the eyelids. Extended: All intraorbital soft tissues are removed, together with adjacent structures(usually bony walls and sinuses).
28. Varieties of orbital exenteration • Anterior (part or full eyelids, conjunctiva, eyeball, anterior orbit) • Anterior and short of apex • Total/radical (all the above upto apex) • Extended (orbit and one of the paranasal sinuses) • Super (exenteration with orbitectomy) • Eyelid-sparing (can be used with any of the above). Following removal of the orbital contents, the bony socket may be  allowed to spontaneously granulate and epithelialize or  covered by a split-thickness skin graft, which may be placed onto bare bone or over a temporalis muscle or temporoparietalfascial flap.
29. Indications • Orbital malignancies  Cutaneous tumours with orbital adnexa invasion including squamous cell carcinoma, basal cell carcinoma, and sebaceous cell carcinoma.  Less common tumors include conjunctival malignant melanoma, adenoid cystic carcinoma of the lacrimal gland, and uveal melanoma with extrascleral extension  Intraocular melanomas or retinoblastomas • Painful or life-threatening orbital infections • Mucormycosis • Chronic orbital pain • Orbital deformities
30. Lid Sparing Exenteration Technique • GA should be used if possible. • If GA is C/I ,local retrobulbar, infraorbital, and periorbital nerve blocks may be used • A 4-0 black silk suture is passed through the skin, orbicularis muscle, and superficial tarsus of the upper and lower lids and tied together to close the eyelids and to provide traction during the procedure. • A skin incision is outlined 2 mm above and below the upper and lower lash line and extended to just beyond the medial and lateral canthi
31. • The incision is placed only through the eyelid skin and orbicularis oculi muscle, which is then undermined superiorly and inferiorly until the periosteum just outside the orbital rim is exposed for 360°. • An incision is then made through the periosteum for 360° about 2 mm outside of the orbital rim to expose the underlying bone. • A periosteal elevator is used to free the periosteum for 360° around the bony orbital margin and into the orbital cavity. • Small bleeding vessels posteriorly between the periosteum and the bone may be difficult to control.
32. • When the periosteum is free posteriorly, the enucleation scissors are inserted between the periosteum and bone on the inferonasal side and gently advanced to the orbital apex. • The tissues are then cut as near to the orbital apex as possible, and the orbital contents are removed by continued traction on the silk sutures in the eyelids while cutting the residual adhesions in the posterior orbit. • The socket is immediately packed with moist gauze, which is left in place for 5 to 10 minutes. • The gauze is then removed and the orbital apex inspected. •
33. • Residual soft tissue at the orbital apex is removed piecemeal, and Bovie cautery and repeat packing are used until there is no further bleeding. • A rubber drain is placed in the socket after complete hemostasis, and the skin of the upper and lower eyelids are sutured together with interrupted 5-0 silk sutures. • This leaves the residual orbital cavity filled with air. • One skin suture is tied to the drain.
34. • The drain suture is removed in 12 to 24 hours, and the drain is removed in 24 to 48 hours, depending on when drainage has ceased. • The skin sutures are removed in about 1 week, and dressings are not required. • The remaining eyelid skin gradually retracts into the socket and provides a more cosmetically acceptable lining of the socket after exenteration. • An orbital prosthesis can be fitted within 3 to 4 weeks.
35. Advantages to a lid-sparing technique • The wound heals faster • less postoperative follow-up is required. • The quicker healing allows radiotherapy where required. • A smooth healthy surface of the socket allows the use of a stick-on orbital prosthesis, rather than a spectacle mounted one.
36. Total Exenteration Technique • Two 4-0 silk tarsorrhaphy sutures are placed which will also act as traction sutures throughout the case. • A monopolar cautery is then used to make an incision through the skin and orbicularis muscle at the orbital rim 360 degrees. • Dissection is the carried out to the orbital rim laterally as well as inferiorly. • The superior orbital rim is identified and the periosteum is elevated. The lateral orbital rim is incised along the periosteum.
37. • Laterally the periosteum is elevated from the lateral orbital rim and lateral wall. • In this area one will usually encounter structures corresponding to the zygomatico facial and zygomatico maxillary neurovascular bundles. • The supraorbital neurovascular bundle is identified and transected with the monopolar cautery. • Medially, the anterior ethmoidal neurovascular bundle is identified and cauterized.
38. • Posteriorly, the posterior ethmoidal neurovascular bundle is identified and cauterized. • After transection of the infraorbital fissure as well as the nasolacrimal duct, the curved scissors are used to transect the posterior obit. • One can apply a snare prior to transection as the ophthalmic artery is transected and there will be significant bleeding. • Hemostasis is attained with the bipolar cautery. • A posterior orbital biopsy can be obtained if needed. • The area is then packed for hemostasis prior to harvesting of the split thickness skin graft.
39. Complications • Extensive bleeding, rarely necessitate a blood transfusion. • Fracture of thin ethmoid bones during the surgery, leading to an opening between the orbit and the nasal cavity. • Postoperative infection-appropriate antibiotics. • Sloughing of the skin graft. • Sino orbital fistula • Intracranial infections –CSF leak can be eliminated by obliterating the cavity in its entirety with soft- tissue free-flaps which provides  a safer and more therapeutic management of the socket leading to improved postoperative management and cosmetic outcome.  protective barrier that protects the cranium from a potential infection.
40. Ideal anophthalmic socket 1. A socket lined with healthy conjunctiva and fornices deep enough to retain a prosthesis and to permit horizontal and vertical movements of an artificial eye 2. Eyelids with normal position ,appearance and adequate tone to support a prosthesis 3. A supratarsal eyelid fold that is symmetric with that of the C/l eyelid
41. 4. Normal position of the eyelashes and eyelid margin 5.A centrally placed, well-covered, buried implant of adequate volume, fabricated from a bio-inert material 6. Good transmission of motility from the implant to the overlying prosthesis 7. A comfortable ocular prosthesis that looks similar to the sighted, contralateral globe and in the same horizontal plane
42. CYCLODESTRUCTIVE PROCEDURES • Destruction of the ciliary body has been used to treat glaucoma since the 1930s. • In cyclodestructive procedures, the secretory epithelium of the ciliary epithelium is damaged, which leads to reduced aqueous humor secretion and lower IOP. • Coagulation of proteins of epithelial cells ,closing nearby capillariesablation of ciliary epithelium without destroying ciliary body • Because the ciliary epithelium can regenerate, multiple treatments are necessary in some patients to achieve the desired long term IOP lowering effect.
43. The different modalities to achieve cyclodestruction are: diathermy, surgical excision, cryotherapy, ultrasound, and laser light Cyclophotocoagulation (CPC) is the most common procedure to perform cyclodestruction. It can be performed using different laser wavelengths • CPC was first performed by Beckman using a ruby laser (693 nm wavelength). • Nd:YAG laser (1064 nm wavelength has been used either with non-contact or contact methods to achieve cyclodestruction.
44. Contact Nd Yag- • Uses hand held probe placed on conjunctiva to to allow energy transmission directly to ocular surface • lesser power required as contact pressure increases scleral transparency • 32 to 40 spots over 360 degrees • 7 watts for 0.7 seconds for each spot Non Contact Nd Yag- • Transmits laser through air from slitlamp delivery system • 32 to 40 spots over 360 degrees • 8 Joules for 20 msec
45. • Presently, diode laser (810 nm wavelength) either transsceral or with an endoscopic probe is used to perform CPC. • The diode laser is preferred over other wavelengths since the melanin in the ciliary epithelium better absorbs this wavelength than others and therefore causes more targeted destruction with less inflammation. • It requires 50 %lesser power than with Nd Yag
46. There are 3 basic approaches to cyclodestruction (cycloablation): • Cyclocryotherapy • Trans-scleral laser cycloablation • Endoscopic laser cycloablation All 3 techniques share the common goal of decreased aqueous production, and all share the possible side effects of inflammation (including possible sympathetic ophthalmia), ineffective treatment, and over-treatment with resultant hypotony or even phthisis.
47. • cycloablation procedures mostly reserved for those cases refractory to, or not amenable to angle surgery, glaucoma drainage implant surgery, and trabeculectomy • For Refractory pediatric glaucoma , cyclodestruction represents a valid method of attempting control of glaucoma that threatens residual vision or causes ongoing damage to the structure of the child's eye. • Conventionally used only in eyes with poor visual potential, but can be employed in cases with reasonable vision to prevent severe glaucomatous damage occurring whilst neovascularization is brought under control. • Lowering IOP improves comfort, and clearing corneal oedema may facilitate an adequate retinal view for PRP • Recently TS-CPC has been performed in patients with good vision with good results.
48. CYCLOCRYOTHERAPY Indications • Other treatment modalities exhausted • Cases when TDC or ECP is anatomically challenging to perform
49. Technique • The oldest cyclodestructive method • involves freezing the ciliary processes from an external approach • reserved for those refractory pediatric glaucoma cases in which anatomy limits the likelihood of successful ciliary body treatment with either trans-scleral or endoscopic cyclophotocoagulation or access to these technologies is truly unavailable and incisional surgery is impossible
50. • cyclocryotherapy in pediatric eyes should be limited to a maximum of 6 clock hours (180 degrees of the eye's circumference) at any 1 session, using approximately 1 freeze-spot per clock-hour (45–60 seconds each at 280ºC) • Given with the anterior edge of a "large" 2.5-mm diameter cryoprobe attached to liquid Nitrogen supply placed at 1–1.5 mm posterior to the limbus in a nonbuphthalmic globe • avoid the 3 and 9 o'clock locations to minimize damage to the long posterior ciliary vessels.
51. • Extent of freeze ball -10 -12 mm , extending up to corneal limbus • Any especially thin area of the limbus should also be avoided • care should be taken to avoid contact with adjacent lid tissue and to shorten treatment if the "freeze zone" gets larger than approximately 1 cm, which can happen as the entire eye "cools down" with sequential freeze applications.
52. • Where limbal anatomy is distorted or difficult to evaluate, transillumination can help identify the proper treatment location. • During cyclocryotherapy repeat sessions, care should be taken to leave at least 1 quadrant untreated because with overtreatment, chronic hypotony or phthisis can be permanent.
53. Advantages • Short surgical time and rapid rehabilitation • Technically easy
54. Disadvantages • Often needs to be repeated due to ciliary body recovery • Most patients remain on medical therapy. • Risk of phthisis bulbi • Scleral thinning at cryo sites can affect future drainage device surgery. • Proinflammatory and can accelerate cataract formation • Post op IOP spike- due to volumetric change in intraocular contents caused by intravitreal iceball.
55. TRANS-SCLERAL DIODE-LASER CYCLOPHOTOCOAGULATION (DIODE TS-CPC) • Laser energy can be directed through the sclera to treat the ciliary processes using a probe in contact with the sclera over the intended treatment site. • Used in pediatric glaucoma, refractory to other measures using both the Nd:YAG laser and the diode laser. • Although reported to produce less inflammation than cyclocryotherapy in adults, risks of serious complications • Ultrasound biomicroscopy recently has been described as a guide to proper placement of the probe for TDC
56. TRANS-SCLERAL DIODE-LASER CYCLOPHOTOCOAGULATION (DIODE TS-CPC) • The only eligibility requirement-eye must have some degree of functioning aqueous outflow. • TSCPC decreases aqueous outflow , thereby decreasing IOP • C/I in Uveitis • Preop vasoconstriction with Alpha agonist (Alphagan P) decrease energy absorption by conjunctival vesselsless likelihood of SCH
57. Indications for Transcleral Cyclophotocoagulation • Elevated IOP with poor vision or poor visual potential • Pain relief due to elevated IOP in a blind painful eye • Uncontrolled glaucoma in the presence of conjunctival scarring from previous surgery • Patient's medical condition preclude going to operating room • Patient refuses surgery in OT • Failed angle surgery and minimal visual potential • Failed trabeculectomy and/or aqueous drainage with poor central vision • Inadequate IOP control after drainage device • Anatomy precluding trabeculectomy or glaucoma drainage device, e.g., disorganized anterior segment, thin limbus • Gravely ill children, poor follow-up, blind in fellow eye from complication of intraocular surgery • Uncontrolled IOP post surgery in Primary open-angle glaucoma,Angle-closure glaucoma,Neovascular glaucoma,Pseudophakic/aphakic glaucoma,Pediatric glaucoma,Glaucoma after penetrating keratoplasty,Uveitic glaucoma,Silicone oil induced glaucoma
58. Procedure • Diode TS-CPC can be performed in a minor procedure room or in an OT. • Retrobulbar or peribulbar anesthesia is needed, as the procedure is painful. • A lid speculum helps to provide better exposure to the peri-limbal area. • A semi-conductor solid state diode laser with a wavelength of 810 nm • A handpiece –G probe is used to deliver the laser energy.
59. • G probe- 600u diameter Quartz glass fibre , placed 1mm posterior to limbus, mild pressure to indent conj and sclera • Initial power of 1250 mW and duration of 4 seconds. • The power is increased in 150 mW increments until an audible “pop” is heard. • The audible “pop” signifies tissue explosion of the ciliary process, the iris root, or the retina
60. • When a “pop” is heard the power is decreased by 150 mW until there is no audible “pop”. • The maximum power used is 2250 mW. • Others will start at 2000 mW and 2 seconds and titrate the energy down. Generally 6 spots are used per quadrant for a total of 18 spots.
61. • Some surgeons recommend treating only 3 quadrants to avoid anterior segment necrosis and many recommend sparing the 3:00 and 9:00 positions. • After completion of the procedure a topical antibiotic, steroid, and cycloplegic agents are placed on the eye. • The eye should be patched after a block is used to protect the cornea. • The patient is seen the next day for follow-up.
62. Advantages • Short surgical time and rapid rehabilitation • Technically easy • Lesser power as compared with cryo as more efficiently absorbed by ciliary body In cryodiffusely absorbed by all structures • Contact method-less scatter , thus less energy required
63. Disadvantages • Often needs to be repeated due to ciliary body recovery • Most patients remain on medical therapy. • Risk of phthisis bulbi, but less than cryo • Beware risk of perforation at sites of scleral thinning. • Proinflammatory and can accelerate cataract formation
64. Complications • IOP spikes –Preop and post op oral CAI –Azetazolamide or Methazolamide • Pain is usually transient and controlled with analgesics • Hyphema more frequently in neovascular glaucoma patients. • Iridocyclitis occurs commonly after TS-CPC. Few patients can develop a chronic low-grade anterior chamber inflammation due to a breakdown in the blood-aqueous barrier. • Conjunctival burns rarely if conjunctival surface becomes dry during laser with high energy settings ,in darkly pigmented conjunctiva and due to the use of defective, damaged, or soiled laser probes. • Hypotony
65. • Vision loss can occur after TS-CPC • Phthisis bulbi is a rare complication • Malignant glaucoma • necrotizing scleritis • sympathetic ophthalmia • Scleral perforation has been reported with TDC so care should be taken to ensure that the probe surface is clean of debris and to avoid areas of obvious scleral thinning and the site of previous surgeries (do not laser where the tube passes and the previous trabeculectomy site).
66. Variation in clinical response • Variation in pressure exerted over sclera • Difference in scleral thickness • Variation in probe inclination
67. ENDOCYCLOPHOTOCOAGULATION (ECP) Employs fibreoptic cable to deliver pulsed continuous wave diode laser energy to ciliary processes under direct endoscopic visualization using video monitor • Used as a treatment for refractory pediatric glaucoma, allowing more precise localization of the target and treatment with much lower energy than required for trans- scleral laser. • The most commonly used system uses a diode laser equipped with a 20-gauge probe, within which is housed fiber optics for a video monitor, diode laser endophotocoagulation, and illumination • ECP can be combined with phacoemulsification to treat cataract and glaucoma at the same time In combined cases ECP can be performed before or after inserting the intraocular lens in the lens bag.
68. Indications for Endocyclophotocoagulation • Same indications as TDC but anatomy of eye allowing limbal or pars plana approach to ciliary processes but beware of cataract in phakic eyes • To Consider after TDC has failed. • Patients who are poor candidates for glaucoma filtration surgery or glaucoma drainage implant • Distorted anterior segments • In uncontrolled Primary open-angle glaucoma,Pseudoexfoliation glaucoma,Neovascular glaucoma,Pseudophakic glaucoma,Glaucoma after penetrating keratoplasty,Glaucoma associated with retinal surgery,Pediatric glaucoma,Angle-closure glaucoma
69. Technique • The ECP laser unit has 4 different components, the diode laser (pulsed continuous-wave energy at 810 nm), a xenon light source, a helium-neon laser aiming beam, and video monitor and recorder. • The probe is 20 gauge with a full view of 110 degrees and depth of focus of 1-30mm. • The equipment console consists of the video camera, light source, video monitor, and the video recorder.
70. • Initially the laser probe is placed into the anterior chamber by looking through the surgical microscope. • Then the surgeon looks through the video monitor to locate the ciliary processes and perform the laser photocoagulation • The goal of each laser application is to whiten and shrink the ciliary process. • The entire ciliary process should be treated. • Generally 270-360 degrees of the ciliary processes are treated.
71. • Gas bubble formation, pigmentary dispersion, audible “pops”, photocoagulation of non-ciliary process tissue should be avoided • The laser settings are as follows: Power 0.2 W, continuous-wave mode. • The power is titrated to achieve whitening and shrinkage of the ciliary process by positioning the probe either closer or further from the processes. • Ideally, 3 processes should be within view during treatment.
72. • ECP can be performed in phakic, pseudophakic, or aphakic eye with the endolaser probe through the limbus or pars plana. In the limbal approach, • a 1.5-2.0 mm incision is made in the clear cornea or sclera. • A cohesive viscoelastic is injected posterior to the iris and anterior to the lens capsule to deepen the ciliary sulcus space. • Next the probe is placed in the anterior chamber. • The ciliary processes are visualized and treated. • The viscoelastic is removed.
73. • In phakic patients great care should be taken not to nick the anterior lens capsule. • In pseudophakic/aphakic eyes, the pars plana approach is advantageous since the ciliary processes are better visualized. • The incision is made 3.5-4.0mm posterior to the limbus. • Infusion port through pars plana • 2 superior entries for vitrectomy and illumination • Anterior vitrectomy is performed for adequate and safe access to ciliary processes • Then cyclophotocoagulation with the endolaser probe is performed.
74. Post-operative Management • Cycloplegics (atropine 1% BD for 2 weeks) • Topical corticosteroids (prednisolone acetate 1% QID; In extensive anterior chamber inflammation increase frequency) • Topical antibiotics • Subtenon’s steroid injection and/or oral steroids • The pre-laser glaucoma medications continued post- operatively and tapered based on the IOP lowering effect of the laser.
75. • Miotics should be stopped because they can enhance the inflammatory response and cause posterior synechiae. • Consideration stopping PG analogs if IOP is well controlled since they can cause anterior chamber inflammation.
76. Advantages • Short surgical time and rapid rehabilitation • Allows precise treatment due to direct visualization and avoids risk of scleral perforation • Important in Severe Congenital Glaucoma where eyeball is enlarged and ciliary processes may be displaced • Can produce less inflammation and collateral tissue damage than TDC and cryo • less power needed
77. Disadvantages • Often needs to be repeated due to ciliary body recovery • Most patients remain on medical therapy • Risk of phthisis bulbi, but less than TDC and cryo • Proinflammatory, but less than TDC and cryotherapy • Intraocular approach with risk of endophthalmitis and cataract formation
78. Complications • IOP spikes • Fibrin exudates • Hyphema • Cystoid edema • Vision loss of 2 lines or more • Hypotony • Zonular damage • Rarely ,phthisis bulbi, endophthalmitis, or sympathetic ophthalmia • Retinal detachment • Serous and haemorrhagic choroidal detachment • Traumatic injury to the iris Mechanical trauma/ laser improperly applied to the iris
79. Transpupillary cyclophotocoagulation • In people with visible ciliary processes • In traumatic aniridia and in people with large iridectomies • in advanced neovascular glaucoma, when iris is pulled ant and peripherally • With a slit lamp delivery system through Goldmann 3 mirror lens • Using Argon green or Nd YAG • 3-4 applications to coagulate all visible portion • End point is blanching of ciliary body, blisters,/effusion of pigment
80. • Cyclodestruction has limited success and the risk of severe complications when used for treatment of refractory pediatric glaucoma. • Nonetheless, this modality retains an important role in the management of selected eyes with refractory glaucoma. • Cyclodestruction in the treatment algorithm depends on several factors  visual potential  anatomic features  prior surgical interventions  glaucoma severity  overall health
81. • Both TDC and ECP can represent adjunctive techniques after prior glaucoma drainage device surgery has incompletely controlled the IOP and can be reasonable primary surgery in selected eyes with challenging anatomy for other intraocular glaucoma procedures. • Cyclodestruction should be used with extreme caution in eyes with uveitis because all 3 techniques produce significant inflammation as well as the potential to produce retinal detachment, hypotony, phthisis, and even sympathetic ophthalmia.
82. References 1. Bosniak –Ophthalmic Plastic and reconstructive Surgery 2. AAO series –Orbit 3. Stellard’s Eye Surgery 4. Becker schaffer’s Diagnosis and therapy of Glaucomas 5. Kanski ‘s Clinical Ophthalmology 6. Post Graduate Ophthalmology by Zia CHaudhuri 6. AAO series- Glaucoma
83. THANK YOU !!