OCULAR PROSTHESISOCULAR PROSTHESIS

Presented by:Presented by:Ashima Goel JRIIAshima Goel JRII

IntroductionIntroduction

The fabrication of an extraoral The fabrication of an extraoral prosthesis is as much an art as it is a prosthesis is as much an art as it is a science.science.

The ideally constructed prosthesis The ideally constructed prosthesis must duplicate the missing facial must duplicate the missing facial feature so precisely that the casual feature so precisely that the casual observer notices nothing that would observer notices nothing that would draw attention to the prosthetic draw attention to the prosthetic reconstruction.reconstruction.

Ocular prosthesisOcular prosthesis

The goal of any ocular prosthetic procedure is The goal of any ocular prosthetic procedure is to return the patient to society with a normal to return the patient to society with a normal appearance and reasonable motility of the appearance and reasonable motility of the prosthetic eye.prosthetic eye.

The disfigurement resulting from loss of an The disfigurement resulting from loss of an eye can cause significant psychological, as eye can cause significant psychological, as well as social consequences.well as social consequences.

However, with the advancement in ophthalmic However, with the advancement in ophthalmic surgery and ocular prosthesis, the surgery and ocular prosthesis, the anophthalmic patient can be rehabilitated anophthalmic patient can be rehabilitated very effectively.very effectively.

Ambroise Pare, a french surgeon-dentist, is Ambroise Pare, a french surgeon-dentist, is considered to be the pioneer of modern considered to be the pioneer of modern artificial eyes.artificial eyes.

In 1575, Pare fabricated artificial eyes made In 1575, Pare fabricated artificial eyes made of glass as well as porcelain. Acrylic resins of glass as well as porcelain. Acrylic resins has replaced this material by the early 1940.has replaced this material by the early 1940.

Unlike a glass eye, an acrylic resin eye was Unlike a glass eye, an acrylic resin eye was easy to fit and adjust, unbreakable, inert to easy to fit and adjust, unbreakable, inert to ocular fluids, esthetically good, longer ocular fluids, esthetically good, longer lasting, and easier to fabricate.lasting, and easier to fabricate.

Surgical considerations in Surgical considerations in ocular implantsocular implants

The surgical procedures in the The surgical procedures in the removal of an eye are classified into removal of an eye are classified into 3 category : 3 category :

EviscerationEvisceration EnucleationEnucleation Exenteration Exenteration

EviscerationEvisceration

It involves removing the contents of the It involves removing the contents of the globe but leaving the sclera and globe but leaving the sclera and sometimes the cornea in place.sometimes the cornea in place.

Motility of the implanted eviscerated Motility of the implanted eviscerated globe is excellent, since the extraocular globe is excellent, since the extraocular muscles are intact.muscles are intact.

Disadvantages –Disadvantages –• Careful selection of the size of Careful selection of the size of

spherical implant-to prevent extrusion spherical implant-to prevent extrusion and exopthalmic appearanceand exopthalmic appearance

• Fitting of the prosthesis may be Fitting of the prosthesis may be difficult –sensitivity of the socketdifficult –sensitivity of the socket

• Prosthesis difficult to fabricate-Prosthesis difficult to fabricate-limited space within the forniceslimited space within the fornices

AdvantageAdvantage Light scleral shell will not depress the Light scleral shell will not depress the

lower eyelid with its weight and the lower eyelid with its weight and the bulk of the material is not required to bulk of the material is not required to fill the sunken superior sulcus.fill the sunken superior sulcus.

EnucleationEnucleation It is the surgical removal of the eyeball after the eye It is the surgical removal of the eyeball after the eye

muscles and optic nerve have been severed.muscles and optic nerve have been severed. The placement of orbital implant into the enucleated The placement of orbital implant into the enucleated

socket was first described by Frost in 1886.socket was first described by Frost in 1886. Soll described the improved surgical method of Soll described the improved surgical method of

placing the orbital implant deep within the muscle placing the orbital implant deep within the muscle cone,and buried beneath the posterior layer of tenons cone,and buried beneath the posterior layer of tenons capsule.capsule.

The optic nerve and its associated vessels are The optic nerve and its associated vessels are severed and tied close to the posterior wall of the severed and tied close to the posterior wall of the capsule.capsule.

The implant is placed, and the posterior portion of The implant is placed, and the posterior portion of Tenons capsule is closed over the implant providing Tenons capsule is closed over the implant providing the first layer of closure.the first layer of closure.

Then, the anterior portion of Tenons Then, the anterior portion of Tenons capsule and conjuctiva are then closed to capsule and conjuctiva are then closed to form the second and third layers over the form the second and third layers over the implant.implant.

Advantages Advantages • Entire globe is available for Entire globe is available for

histopathological examination histopathological examination • Risk of spreading an ocular tumor is Risk of spreading an ocular tumor is

negatednegated• Prevention of sympathetic opthalmia Prevention of sympathetic opthalmia • Adequate space for fabricating prosthesisAdequate space for fabricating prosthesis

It the movement of the fornix in the It the movement of the fornix in the enucleated socket that provides the enucleated socket that provides the motility to the artificial eye.motility to the artificial eye.

Utilizing the posterior wall of tenons Utilizing the posterior wall of tenons capsule,a larger implant can be placed capsule,a larger implant can be placed decreasing the incidence of implant decreasing the incidence of implant migration,and reducing the tension on migration,and reducing the tension on the anterior tenons capsule sutures.the anterior tenons capsule sutures.

Reduces volume deficit in superior and Reduces volume deficit in superior and inferior sulcus,preventing enopthalmos.inferior sulcus,preventing enopthalmos.

ExenterationExenteration

It is the removal of the entire It is the removal of the entire content of the orbit including the content of the orbit including the extraocular muscles.extraocular muscles.

Materials and types of Materials and types of ocular implantsocular implants

The first material used for orbital The first material used for orbital implants was glass.implants was glass.

Mules introduced the hollow spherical Mules introduced the hollow spherical glass implant in 1884,which is still used glass implant in 1884,which is still used today and prefered by many today and prefered by many opthalmologists.opthalmologists.

Since that time, many materials have Since that time, many materials have been tried, including cartilage, fat, bone, been tried, including cartilage, fat, bone, silk, wool aluminium, cork, silk, wool aluminium, cork, ivory ,vaseline, and paraffin. ivory ,vaseline, and paraffin.

Ocular implants are Ocular implants are classified :classified :

IntegratedIntegrated Semi-integratedSemi-integrated Non-integrated Non-integrated

Buried Buried Non buried Non buried

Integrated and non-buried Integrated and non-buried implantimplant

Rudermann Rudermann introduced the first introduced the first partially exposed,non partially exposed,non buried, integrated buried, integrated implant. But these implant. But these implants had limited implants had limited success due to success due to extrusion,migration extrusion,migration and excessive and excessive infection rate. They infection rate. They were abandoned by were abandoned by the 1950.the 1950.

Semi-integrated and buried Semi-integrated and buried implantsimplants

These implants consist These implants consist of an acrylic resin of an acrylic resin implants with four implants with four protruding mounds on protruding mounds on the anterior surface., the anterior surface., these acrylic resin these acrylic resin mounds on the implant mounds on the implant protrude against the protrude against the encapsulating tissue.encapsulating tissue.

Since this implant is Since this implant is buried, there is always buried, there is always tissue between the tissue between the implant and the ocular implant and the ocular prosthesis.prosthesis.

The “keying” effect of the protruding The “keying” effect of the protruding tissue mounds against the ocular tissue mounds against the ocular prosthesis provide excellent support and prosthesis provide excellent support and motility.motility.

Common complication of implant was the Common complication of implant was the exposure of the resins mounds with time, exposure of the resins mounds with time, resulting in implant extrusion.resulting in implant extrusion.

Non-integrated and buried Non-integrated and buried implantimplant

The buried, non The buried, non integrated implant integrated implant is the most is the most common method of common method of replacing volume replacing volume loss in the socket loss in the socket following following enucleation or enucleation or evisceration. evisceration.

The implant consist of hollow or a The implant consist of hollow or a solid acrylic resin sphere (Mules solid acrylic resin sphere (Mules sphere)10 to 22 mm in diameter.sphere)10 to 22 mm in diameter.

The spherical surface is easy to fit The spherical surface is easy to fit with the prosthesis and it tend to with the prosthesis and it tend to minimise pressure and friction.minimise pressure and friction.

However, prosthesis motility was However, prosthesis motility was limited due to the lack of coupling of limited due to the lack of coupling of the implant to the prosthesis. the implant to the prosthesis.

Hydroxyapatite integrated Hydroxyapatite integrated ocular implant ocular implant

The first orbital implant made of The first orbital implant made of hydroxyapatite was implanted in 1985, by Dr. hydroxyapatite was implanted in 1985, by Dr. Arthur Perry, after several years of Arthur Perry, after several years of preliminary research. preliminary research.

The movement is automatically transferred The movement is automatically transferred to the artificial eye. If greater movement is to the artificial eye. If greater movement is desired, a titanium peg is used to connect the desired, a titanium peg is used to connect the artificial eye to the implant. In this way, even artificial eye to the implant. In this way, even the small, darting movements of the natural the small, darting movements of the natural eye can be transformed directly to the eye can be transformed directly to the artificial eye. artificial eye.

Allows vascular ingrowth of tissue which limits Allows vascular ingrowth of tissue which limits migration of implantmigration of implant

A bone scan (Tc 99) or MRI test with contrast A bone scan (Tc 99) or MRI test with contrast should be performed to confirm whether the should be performed to confirm whether the implant had adequate vascular ingrowth implant had adequate vascular ingrowth

After satisfactory vascular ingrowth into HA After satisfactory vascular ingrowth into HA implant (~6 months) , a hole can be drilled implant (~6 months) , a hole can be drilled into the implantinto the implant

A surgical guide stent aids in drilling the guide A surgical guide stent aids in drilling the guide hole in the proper position hole in the proper position

healing peg is then inserted to maintain healing peg is then inserted to maintain integrity of the hole while the growth integrity of the hole while the growth develops into and around the holedevelops into and around the hole

Conjunctiva migrates into hole and vascular Conjunctiva migrates into hole and vascular ingrowth will support a conjuntival ingrowth will support a conjuntival epithelium which lines the drill holeepithelium which lines the drill hole

A sterile motility peg then replaces healing A sterile motility peg then replaces healing

peg that fits into hole in the implantpeg that fits into hole in the implant

Once the peg is Once the peg is placed in the implant, placed in the implant, a month of healing is a month of healing is suggested before the suggested before the back of the artificial back of the artificial eye is modified to eye is modified to accept the head of the accept the head of the pegpeg

AdvantagesAdvantages• The peg in the implant can

help hold the weight of the artificial eye, reducing the downward push on the lower eyelid.

Less likely to become infected Less likely to become infected ,since it is incorporated with ,since it is incorporated with host blood vessel and immune host blood vessel and immune defences are improved .defences are improved .

Unlikely to extrude because it Unlikely to extrude because it is biologically fixed .is biologically fixed .

Disadvantages Disadvantages

Cost of the implant Cost of the implant The requirement and expense of the The requirement and expense of the

2nd stage drilling procedure2nd stage drilling procedure The required modifications to the The required modifications to the

artificial eye.artificial eye. Scans used to determine whether Scans used to determine whether

or not the implant is vascularised or not the implant is vascularised and safe to drilland safe to drill

Ocular impressionOcular impression A thorough A thorough

examination of the examination of the enucleated socket enucleated socket must be made to must be made to ensure proper healing ensure proper healing and the absence of and the absence of infection.infection.

.5% Tetracaine .5% Tetracaine hydrochloride is used hydrochloride is used as a surface anesthetic as a surface anesthetic to reduce the to reduce the irritability of mucosa irritability of mucosa while taking while taking impression.impression.

An impression of the socket An impression of the socket

is made with an ophthalmic is made with an ophthalmic irreversible hydrocolloid in irreversible hydrocolloid in

stock acrylic resin stock acrylic resin impression tray having a impression tray having a hollow handle which hollow handle which accommodate an impression accommodate an impression syringe for the material to syringe for the material to be injected directly into the be injected directly into the socket during impression socket during impression making.making.

The patient is seated in an The patient is seated in an erect position with the head erect position with the head tilted backward at approx. tilted backward at approx. 45 degree, while the socket 45 degree, while the socket is being filled with the is being filled with the impression material. impression material.

Once filled the head is moved back to the Once filled the head is moved back to the vertical position and the patient is directed vertical position and the patient is directed to move their eyes both up and down. to move their eyes both up and down.

This will facilitate the flow of the impression This will facilitate the flow of the impression material into all the aspects of the socket.material into all the aspects of the socket.

After the material sets, the cheek, nose and After the material sets, the cheek, nose and eyebrow regions are massage to break the eyebrow regions are massage to break the seal.seal.

While the patients gazes upward, the cheek While the patients gazes upward, the cheek is pulled down and the inferior portion of the is pulled down and the inferior portion of the impression is rotated out of the socket.impression is rotated out of the socket.

Then the impression is checked for accuracy Then the impression is checked for accuracy and voids. and voids.

Preparation of the castPreparation of the cast The impression is poured in The impression is poured in

2 section with dental stone.2 section with dental stone. The first poured stone is The first poured stone is

coated with a separating coated with a separating medium, such as a tin foil medium, such as a tin foil substitute and allowed to substitute and allowed to dry.dry.

The second half of the mold The second half of the mold is poured with dental stone, is poured with dental stone, leaving funnel shaped hole leaving funnel shaped hole around the stem of the tray.around the stem of the tray.

This hole will be used as a This hole will be used as a funnel to fill the mold with funnel to fill the mold with molten wax. After the dental molten wax. After the dental stone has set, the 2 halves stone has set, the 2 halves of the mold are separated of the mold are separated and the impression material and the impression material is removed.is removed.

Wax patternWax pattern Ivory inlay wax is used Ivory inlay wax is used

for wax pattern. After for wax pattern. After the wax has melted, it the wax has melted, it is poured through the is poured through the funnel shaped hole into funnel shaped hole into the assembled mold.the assembled mold.

After the wax has After the wax has cooled, the mold is cooled, the mold is opened and the wax opened and the wax pattern trimmed, pattern trimmed, smoothed and smoothed and polished.polished.

Then it is ready to be Then it is ready to be tried in the eye socket.tried in the eye socket.

The wax pattern will feel The wax pattern will feel comfortable to most comfortable to most patient, but in some patient, but in some instance, it may cause instance, it may cause mild irritation.mild irritation.

The wax will not move as The wax will not move as freely as the finished freely as the finished acrylic resin prosthesis, acrylic resin prosthesis, but the application of an but the application of an ophthalmic lubricant will ophthalmic lubricant will aid movement.aid movement.

Pressure points or areas Pressure points or areas of discomfort should be of discomfort should be noted and relieved as noted and relieved as necessary. necessary.

Iris PositionIris Position The wax pattern is The wax pattern is

inserted in the socket inserted in the socket and the patient and the patient instructed to look instructed to look straight ahead at a straight ahead at a distant point distant point

Using the companion Using the companion eye for comparison ,the eye for comparison ,the iris position is located iris position is located on wax pattern with on wax pattern with indelible marking indelible marking pen,using the inner pen,using the inner canthus and inner edge canthus and inner edge of the limbus as the of the limbus as the points of reference and points of reference and also in relationship to also in relationship to the opening of the lids.the opening of the lids.

Fabrication of the scleraFabrication of the sclera The wax sclera is now ready to be invested. The wax sclera is now ready to be invested.

After filling the lower portion of the flask After filling the lower portion of the flask with dental stone ,Stone is carefully vibrated with dental stone ,Stone is carefully vibrated onto the posterior surface of the wax onto the posterior surface of the wax pattern.pattern.

The wax pattern is laid on top of the stone in The wax pattern is laid on top of the stone in the flask, taking care not to entrap air.the flask, taking care not to entrap air.

After the stone has set, it is coated with a After the stone has set, it is coated with a separating medium, such a tinfoil substitute.separating medium, such a tinfoil substitute.

Then the flask is reassembled, the upper half Then the flask is reassembled, the upper half of the flask is filled with dental stone, and of the flask is filled with dental stone, and the flask lid is placed on top to close the the flask lid is placed on top to close the mold.mold.

After the stone has set, After the stone has set, the flask is separated the flask is separated by gently pyring it by gently pyring it apart .apart .

The wax pattern is The wax pattern is lifted out and the mold lifted out and the mold is checked for voids.is checked for voids.

After the mold is After the mold is cleaned, a coat of cleaned, a coat of tinfoil substitute is tinfoil substitute is applied to both sides.applied to both sides.

Then white scleral Then white scleral acrylic resin is packed acrylic resin is packed into the mold and into the mold and processed at 150° f for processed at 150° f for 9 hrs, followed by 212 9 hrs, followed by 212 °f for 2 hrs.°f for 2 hrs.

Selection of iris Selection of iris componentcomponent

Ocular discs which Ocular discs which are used in the iris are used in the iris painting, are available painting, are available in half mm sized in half mm sized increments, ranging increments, ranging from 11mm to13mm.from 11mm to13mm.

They come in black or They come in black or clear, and either with clear, and either with or without pupil or without pupil apertures. apertures.

Clear corneal buttons Clear corneal buttons are available in the are available in the same size as the disc. same size as the disc.

Painting the iris and Painting the iris and sclerasclera

There are 5 basic component There are 5 basic component to painting an iris, namely, to painting an iris, namely, the pupil, base color, the the pupil, base color, the detail, collarette and the detail, collarette and the limbus.limbus.

Iris painting is usually Iris painting is usually completed in 2 stages:completed in 2 stages:

First the basic color of the First the basic color of the body of the iris is selected , body of the iris is selected , the base color is usually the base color is usually blue, gray, green, brown or blue, gray, green, brown or a combination of these a combination of these colors.colors.

Then, one or 2 coats of the Then, one or 2 coats of the mono-poly syrup is applied mono-poly syrup is applied to the painted surface of the to the painted surface of the iris disc and allowed to dry. iris disc and allowed to dry.

Adhering the painted disc Adhering the painted disc to the corneal button and to the corneal button and

processingprocessing To adhere the painted disc To adhere the painted disc

to the corneal button the to the corneal button the disc is placed on a flat disc is placed on a flat surface, with painted side surface, with painted side up.up.

1 or 2 drops of monopoly is 1 or 2 drops of monopoly is applied to the painted applied to the painted surface immediately.surface immediately.

The corneal button is The corneal button is position on top of the position on top of the painted disc and press down painted disc and press down lightly until excess lightly until excess monopoly is forced out &the monopoly is forced out &the corneal button is seated corneal button is seated firmly on the disc, the firmly on the disc, the assembly is allowed to dry assembly is allowed to dry for about 30 mins.for about 30 mins.

Now the corneal Now the corneal button is ready to be button is ready to be inserted into the inserted into the mold.mold.

The scleral polymer is The scleral polymer is mixed with monomer. mixed with monomer.

Once the acrylic resin Once the acrylic resin is in the dough stage is in the dough stage it is added to the top it is added to the top of the button and two of the button and two half of the flask press half of the flask press together under together under pressure.pressure.

Then processing is Then processing is done.done.

Scleral and second iris Scleral and second iris paintingpainting

After processing and removal, reduction After processing and removal, reduction of anterior curvature of the prosthesis is of anterior curvature of the prosthesis is done to allow room for scleral and second done to allow room for scleral and second iris painting.iris painting.

Reduction is approx. 1mm and is done by Reduction is approx. 1mm and is done by pear shaped bur.pear shaped bur.

After smoothening of reduced surface a After smoothening of reduced surface a layer of monopoly is applied and allow to layer of monopoly is applied and allow to dry. Now prosthesis is ready for painting.dry. Now prosthesis is ready for painting.

Spokes of the iris are painted by using Spokes of the iris are painted by using either a small ‘ooo’ brush or by flaring the either a small ‘ooo’ brush or by flaring the hair of larger brushhair of larger brush

The collarette which is a circular area or star The collarette which is a circular area or star burst found around the outside border of burst found around the outside border of pupil is painted with lighter or brighter color pupil is painted with lighter or brighter color to that of the body of iris.to that of the body of iris.

Finally the limbus is added this is the area at Finally the limbus is added this is the area at the junction of the iris and sclera, it is the junction of the iris and sclera, it is usually a combination of grays and iris body usually a combination of grays and iris body color.color.

Then the next step is Then the next step is scleral painting, the scleral painting, the natural sclera has veins natural sclera has veins present that are usually present that are usually apparent in both the nasal apparent in both the nasal and temporal corners of and temporal corners of the eye.the eye.

Red cotton fibers are used Red cotton fibers are used to replicate the veins ,then to replicate the veins ,then the fibres are separated the fibres are separated and cut from commercially and cut from commercially available thread.available thread.

The pattern of the natural The pattern of the natural eye are copied by tacking eye are copied by tacking the fibres to the sclera the fibres to the sclera with a brush and with a brush and monomer.monomer.

The colors found in the The colors found in the sclera are usually yellow sclera are usually yellow and blue or combination .and blue or combination .

Once completed a coat of Once completed a coat of monopoly is applied to the monopoly is applied to the sclera. sclera.

Final processingFinal processing It is done by clear heat cured It is done by clear heat cured

resin.resin. The eye is placed into the The eye is placed into the

tissue side of the molds tissue side of the molds anterior curvature facing up.anterior curvature facing up.

The acrylic resin dough is The acrylic resin dough is placed on the painted surface placed on the painted surface ..

After processing and removal After processing and removal the surface is smoothed with the surface is smoothed with a fine white stone and a fine white stone and polished with flour of pumice.polished with flour of pumice.

Delivery of prosthesisDelivery of prosthesis The prosthetic eye is washed with soap The prosthetic eye is washed with soap

&water, a drop or two of an ophthalmic &water, a drop or two of an ophthalmic lubricant on the surface of the prosthesis lubricant on the surface of the prosthesis will facilitate insertion.will facilitate insertion.

After insertion eye are examined for After insertion eye are examined for aesthetic appearance and the degree of aesthetic appearance and the degree of movement by instructing the patient to movement by instructing the patient to perform the movement in various direction.perform the movement in various direction.

Necessary adjustment were carried and Necessary adjustment were carried and the prosthesis was finished , polished and the prosthesis was finished , polished and inserted. inserted.

Thank you Thank you