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.
11. • 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)
12. • 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
13. • 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”
14. 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.
15. 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 .
16.
17.
18.
19. ADVANTAGES OF EVISCERATION
OVER ENUCLEATION
• Less disruption of orbital anatomy.
• Good motility of prosthesis
• Lower rate of migration ,extrusion ,
reoperation.
20. 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)
22. 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
23. 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.
24. 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).
25.
26. 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
27. 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
28. 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).
29. • 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.
30. NON POROUS INERT SPHERICAL IMPLANTS
Advantages
• Provide comfort and low rates of extrusion.
• Cost-effective choice in patients.
Disadvantages
• decreased motility and implant migration.
31. 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.
•
34. 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
35. 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™.
36.
37. 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
39. 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)
40. 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
46. 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%)
47. 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),
48. 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).
49. 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
50. 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.
51. 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
52. 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….
