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Iris reconstruction with a multipiece endocapsular prosthesis in iridocorneal endothelial syndrome
J CATARACT REFRACT SURG - VOL 31, NOVEMBER 2005
TECHNIQUES
Iris reconstruction with a multipiece endocapsular prosthesis in iridocorneal endothelial syndrome Christopher Khng, MD, Michael E. Snyder, MD
Iris reconstruction in cases of iridocorneal endothelial (ICE) syndrome is extremely challenging because of the nature of the iris tissue, which is typically friable and poorly suited to suture repair. Reconstruction in such cases often requires artificial iris implantation. This report illustrates cataract extraction and iris reconstruction with a multipiece endocapsular iris prosthesis that can be inserted through a small incision. Maintenance of a small incision size is a distinct advantage when glaucoma is coexistent in patients with ICE syndrome. It also demonstrates the presence of an ICE membrane over the anterior capsule and the importance of recognizing this membrane rather than confusing it with the anterior capsule when performing the capsulorhexis. J Cataract Refract Surg 2005; 31:2051–2054 Q 2005 ASCRS and ESCRS
Iridocorneal endothelial (ICE) syndrome is a spectrum of conditions affecting the eye. Iris nevus (Cogan-Reese) syndrome, Chandler’s syndrome, and essential iris atrophy are all manifestations of the disease spectrum. Associated ocular pathology includes glaucoma as well as corneal and iris changes. Iris changes may manifest as stromal atrophy, corectopia, pseudopolycoria, and the induced nodular irregularity of iris nevus syndrome, created by evaginations of iris stroma through holes in the multilaminar membrane that covers the iris in this condition. In any case in which the pupil is displaced or enlarged or if the stroma is insufficient to block light, glare and other unwanted optical phenomena may occur. Attempts to address iris deficiencies in ICE syndrome and other iris dysfunctions have included placement of artificial iris prostheses. The use of large, single-piece iris implants was first reported in cases of congenital and Accepted for publication April 5, 2005. From the Cincinnati Eye Institute (Khng, Snyder), Cincinnati, Ohio, USA, and the Eye Institute (Khng), Tan Tock Seng Hospital, Singapore, Singapore. Neither author has a financial or proprietary interest in any material or method mentioned. Reprint requests to Michael E. Snyder, MD, Cincinnati Eye Institute, 10494 Montgomery Road, Cincinnati, Ohio 45242, USA. E-mail: [email protected]. Q 2005 ASCRS and ESCRS Published by Elsevier Inc.
traumatic aniridia. Rosenthal1 reported the use of interdigitating black poly(methyl methacrylate) (PMMA) iris prostheses inserted through small incisions in an eye with anterior segment dysgenesis. The Iris Prosthetic System (IPS) from Ophtec is a modular system meant for capsular bag placement for iris reconstruction and includes singleelement and dual-element iris pieces, a capsular tension ring, and a locking device to hold the pieces in place. The Ophtec multipiece device, available in colored PMMA material, has been available in Europe for several years but is not approved by the Food and Drug Administration in the United States. Its use was described in 1999 (H. Hermeking, MD, ‘‘Absence or Deficiencies of the Iris: What Procedure?’’ film presented at the ASCRS Symposium on Cataract, IOL and Refractive Surgery, Seattle, Washington, USA, April 1999) as well as in the Video Journal of Ophthalmology.2 We believe that our case is the first in the peer-reviewed literature to describe iris prosthesis implantation using the Ophtec multipiece device. SURGICAL TECHNIQUE
A 37-year-old white woman was referred for an evaluation for cataract extraction and iris reconstruction at the Cincinnati Eye Institute for disabling glare outdoors and gradual deterioration in vision in the right eye over the previous few years. She had a longstanding history of ICE 0886-3350/05/$-see front matter doi:10.1016/j.jcrs.2005.04.030
2051
TECHNIQUES: KHNG
syndrome in the right eye with a significant amount of peripheral anterior synechiaes (PAS) and iris melting holes. She previously had mitomycin-augmented trabeculectomy followed by placement of a Baerveldt tube shunt superotemporally. This achieved adequate, sustained intraocular pressure control in the right eye. Examination of a white right eye with a clear cornea and a beaten-metal appearance of the corneal endothelium. No afferent pupil defect was present. The anterior chamber was quiet, but the iris was abnormal with features of the essential iris atrophy variant of ICE syndrome. The pupil was nasally decentered with ectropion uveae and 2 large atrophic iris melting holes temporally and inferiorly. Extensive areas of PAS were present, and the Baerveldt tube was in good position. The crystalline lens was about 1.5 mm superiorly decentered and had grade P4 posterior subcapsular changes on the Lens Opacities Classification System. The lens equator, zonular attachments, and ciliary processes could be seen through the melting holes (Figure 1). No phacodonesis was present, and no vitreous was observed in the anterior chamber. The anterior segment in the left eye was entirely normal with a dark blue iris. Visual acuity in the right eye was 20/50, which decreased to 20/400 on provocation by glare. Intraocular pressure in the right eye was 17 mm Hg without ocular antihypertensives. Dilated fundus examination revealed a cup-to-disc ratio of 0.75 in the right eye and 0.50 in the left eye, with normal macula, retinal vessels, and periphery. The patient could no longer tolerate the photophobia and glare disability and requested cataract surgery and prosthetic iris implantation. Limbal relaxing incisions
were placed on the steep axis of 100 degrees and 290 degrees at the beginning of the procedure to correct 2 diopters of keratometric cylinder. The iris remnants over the central lens were trimmed with Vannas scissors and retracted with a self-retaining iris hook to allow access to the anterior capsule and cataractous lens material. An evanescent, fibrotic ICE membrane was peeled from the surface of the anterior capsule. Capsulorhexis was performed with the assistance of indocyanine green (ICG). Phacoemulsification through a temporal corneal approach proceeded uneventfully. Following cortical cleanup and posterior capsule polishing, a capsular tension ring (Ophtec) placement achieved adequate bag stabilization and recentration a single-piece hydrophobic acrylic intraocular lens (IOL) (Alcon SA60AT) was implanted in the capsular bag. The wound was enlarged to approximately 4.0 mm. Two brown Ophtec type DE1 double-element iris prosthesis devices were then serially implanted in the capsular bag in front of the IOL (Figure 2), and the elements were then dialed orthogonally, establishing a complete iris diaphragm. A brown Ophtec fixation element was then placed to lock the DE1 pieces together (Figure 3). No manipulation or stretching of the atrophic remnant iris was attempted.
Figure 1. Preoperative photograph of the right eye showing the superonasally decentered pupil and 2 atrophic ICE melting holes. The crystalline lens is cataractous with posterior subcapsular changes and is decentered superiorly.
Figure 2. Correct insertion of iris device into the capsular bag is facilitated by identification of the capsulorhexis edge (arrow). Portions of the device already in the capsular bag are easily identified (asterisk) because of stained anterior capsule. An iris hook retracts the iris remnant to facilitate visibility.
2052
RESULTS
Postoperatively, the patient felt that the quality of her vision in that eye had improved considerably and that she was no longer troubled by photophobia or glare outdoors. The uncorrected visual acuity improved to 20/30 at 6 weeks of
J CATARACT REFRACT SURG - VOL 31, NOVEMBER 2005
TECHNIQUES: KHNG
Figure 3. Postoperative appearance showing the iris elements dialed orthogonally and secured with a locking ring.
follow-up, and the patient was pleased with both the functional and the cosmetic result. The iris prosthesis complex was well centered, and the IOL was in excellent position. Intraocular pressure remained in the midteens without medication, and the Baerveldt tube was in good position. DISCUSSION
Iris reconstruction in ICE syndrome is exceedingly difficult owing to the typically stiff and friable nature of the iris stroma. Accordingly, repair using sutures in these cases generally yields poor results. Although iris prostheses have been reported in ICE patients (K.J. Rosenthal, MD, presented at the AAO Annual Meeting, Anaheim, California, USA, 2003), the single-piece designs (Morcher, Ophtec) require a large incision (9.0 to 10.0 mm). In glaucoma patients, a small incision is a distinct advantage. Paired Morcher type 50-C devices can be inserted through a 3.5 mm incision but are only available in black PMMA, which is brittle3,4 and cosmetically less desirable in patients with all but the darkest irides. The iris prosthetic devices from Ophtec are available in 4 colors: light blue, light green, brown, and black. Unless the patient’s natural iris color is a very light blue, we have usually opted to implant the midbrown device because we believe it provides the best cosmetic result. The color intensities (saturation and brightness) of the light blue and light green implants may be too disparate from a darker fellow iris to prevent a distracting contrast. In contradistinction, the brown implants are often of a similar degree of intensity to a green or dark blue iris; they often look like congenital heterochromia and provide with satisfactory cosmesis. The dual elements of the IPS system do not completely fill the peripheral capsular bag in the quadrants oblique to
the elements’ long axes; however, the area of peripheral bag exposure creates 4 shallow triangular spaces, less than 1.0 mm at greatest radial dimension. Although the Morcher 50 series elements extend to the bag periphery for 360 degrees, the pupillary aperture varies with the element chosen (50-C, D, or E) and those with smaller apertures require progressively larger incisions. As in our patient, an ICE membrane of proliferating cells may exist over some or all of the anterior chamber structures, including the trabecular meshwork, iris, and lens capsule. It is important in these cases not to confuse this ICE membrane for the anterior capsule.5 Often the membrane can be peeled starting at an area of posterior synechias. It is vital not to mistake the ICE membrane for the capsule and inadvertently believe that a capsulorhexis has been created when it has not. In this case, ICG dye was used even though the cataract was not dense and a good red reflex was present. Our preference is to use capsule staining in cases in which zonular compromise exists or an opaque implant is to be placed in the capsular bag. Capsule staining facilitates identification and orientation of the capsular bag periphery and capsulorhexis margin in later steps of the procedure, when they may deviate from their native positions as lens material is removed. Capsule dye also aids in proper endocapsular placement of iris prosthetic devices because the capsule edge cannot be seen well with an opaque device preventing a red reflex. The stained capsule creates a green tinge over the surface of the device when the implant is placed below the anterior capsule leaflet. We believe that the routine use of capsule stain may lead to enhanced safety when multiple devices are to be placed in the bag and the success of the surgical outcome depends on the integrity of the anterior capsule rim and bag. Insertion of multipiece devices in the bag requires several gentle but dexterous manipulations in combination with a keen awareness of the location of the anterior capsulorhexis. The long-term stability of intracapsularly placed devices in eyes with questionably weakened zonules has yet to be established. The weight of additional hardware placed in the capsular bag may create stress on the zonules over time from normal saccade movements or, in particular, in patients with nystagmus. For cases in which iris repair is not a suitable option and a small incision is desirable, a multipiece iris device can provide a good cosmetic result and relief from the symptoms associated with loss of an intact iris diaphragm.
REFERENCES 1. Rosenthal KJ. Sutureless phacotrabeculectomy and insertion of an iris diaphragm ring in a patient with the Axenfeld-Reiger syndrome: first reported case. Video Cataract Refract Surg 1997; 13(2)
J CATARACT REFRACT SURG - VOL 31, NOVEMBER 2005
2053
TECHNIQUES: KHNG
2. Hermeking H. Iris prosthetic system. Video Cataract Refract Surg 1999; 15(4) 3. Burk SE, Da Mata AP, Snyder ME, et al. Prosthetic iris implantation for congenital, traumatic, or functional iris deficiencies. J Cataract Refract Surg 2001; 27:1732–1740
2054
4. Osher RH, Burk SE. Cataract surgery combined with implantation of an artificial iris. J Cataract Refract Surg 1999; 25:1540–1547 5. Azuara-Blanco A, Wilson RP, Eagle RC Jr, Rafferty PA. Pseudocapsulorrhexis in a patient with iridocorneal endothelial syndrome. Arch Ophthalmol 1999; 117:397–398
J CATARACT REFRACT SURG - VOL 31, NOVEMBER 2005
TECHNIQUES
Iris reconstruction with a multipiece endocapsular prosthesis in iridocorneal endothelial syndrome Christopher Khng, MD, Michael E. Snyder, MD
Iris reconstruction in cases of iridocorneal endothelial (ICE) syndrome is extremely challenging because of the nature of the iris tissue, which is typically friable and poorly suited to suture repair. Reconstruction in such cases often requires artificial iris implantation. This report illustrates cataract extraction and iris reconstruction with a multipiece endocapsular iris prosthesis that can be inserted through a small incision. Maintenance of a small incision size is a distinct advantage when glaucoma is coexistent in patients with ICE syndrome. It also demonstrates the presence of an ICE membrane over the anterior capsule and the importance of recognizing this membrane rather than confusing it with the anterior capsule when performing the capsulorhexis. J Cataract Refract Surg 2005; 31:2051–2054 Q 2005 ASCRS and ESCRS
Iridocorneal endothelial (ICE) syndrome is a spectrum of conditions affecting the eye. Iris nevus (Cogan-Reese) syndrome, Chandler’s syndrome, and essential iris atrophy are all manifestations of the disease spectrum. Associated ocular pathology includes glaucoma as well as corneal and iris changes. Iris changes may manifest as stromal atrophy, corectopia, pseudopolycoria, and the induced nodular irregularity of iris nevus syndrome, created by evaginations of iris stroma through holes in the multilaminar membrane that covers the iris in this condition. In any case in which the pupil is displaced or enlarged or if the stroma is insufficient to block light, glare and other unwanted optical phenomena may occur. Attempts to address iris deficiencies in ICE syndrome and other iris dysfunctions have included placement of artificial iris prostheses. The use of large, single-piece iris implants was first reported in cases of congenital and Accepted for publication April 5, 2005. From the Cincinnati Eye Institute (Khng, Snyder), Cincinnati, Ohio, USA, and the Eye Institute (Khng), Tan Tock Seng Hospital, Singapore, Singapore. Neither author has a financial or proprietary interest in any material or method mentioned. Reprint requests to Michael E. Snyder, MD, Cincinnati Eye Institute, 10494 Montgomery Road, Cincinnati, Ohio 45242, USA. E-mail: [email protected]. Q 2005 ASCRS and ESCRS Published by Elsevier Inc.
traumatic aniridia. Rosenthal1 reported the use of interdigitating black poly(methyl methacrylate) (PMMA) iris prostheses inserted through small incisions in an eye with anterior segment dysgenesis. The Iris Prosthetic System (IPS) from Ophtec is a modular system meant for capsular bag placement for iris reconstruction and includes singleelement and dual-element iris pieces, a capsular tension ring, and a locking device to hold the pieces in place. The Ophtec multipiece device, available in colored PMMA material, has been available in Europe for several years but is not approved by the Food and Drug Administration in the United States. Its use was described in 1999 (H. Hermeking, MD, ‘‘Absence or Deficiencies of the Iris: What Procedure?’’ film presented at the ASCRS Symposium on Cataract, IOL and Refractive Surgery, Seattle, Washington, USA, April 1999) as well as in the Video Journal of Ophthalmology.2 We believe that our case is the first in the peer-reviewed literature to describe iris prosthesis implantation using the Ophtec multipiece device. SURGICAL TECHNIQUE
A 37-year-old white woman was referred for an evaluation for cataract extraction and iris reconstruction at the Cincinnati Eye Institute for disabling glare outdoors and gradual deterioration in vision in the right eye over the previous few years. She had a longstanding history of ICE 0886-3350/05/$-see front matter doi:10.1016/j.jcrs.2005.04.030
2051
TECHNIQUES: KHNG
syndrome in the right eye with a significant amount of peripheral anterior synechiaes (PAS) and iris melting holes. She previously had mitomycin-augmented trabeculectomy followed by placement of a Baerveldt tube shunt superotemporally. This achieved adequate, sustained intraocular pressure control in the right eye. Examination of a white right eye with a clear cornea and a beaten-metal appearance of the corneal endothelium. No afferent pupil defect was present. The anterior chamber was quiet, but the iris was abnormal with features of the essential iris atrophy variant of ICE syndrome. The pupil was nasally decentered with ectropion uveae and 2 large atrophic iris melting holes temporally and inferiorly. Extensive areas of PAS were present, and the Baerveldt tube was in good position. The crystalline lens was about 1.5 mm superiorly decentered and had grade P4 posterior subcapsular changes on the Lens Opacities Classification System. The lens equator, zonular attachments, and ciliary processes could be seen through the melting holes (Figure 1). No phacodonesis was present, and no vitreous was observed in the anterior chamber. The anterior segment in the left eye was entirely normal with a dark blue iris. Visual acuity in the right eye was 20/50, which decreased to 20/400 on provocation by glare. Intraocular pressure in the right eye was 17 mm Hg without ocular antihypertensives. Dilated fundus examination revealed a cup-to-disc ratio of 0.75 in the right eye and 0.50 in the left eye, with normal macula, retinal vessels, and periphery. The patient could no longer tolerate the photophobia and glare disability and requested cataract surgery and prosthetic iris implantation. Limbal relaxing incisions
were placed on the steep axis of 100 degrees and 290 degrees at the beginning of the procedure to correct 2 diopters of keratometric cylinder. The iris remnants over the central lens were trimmed with Vannas scissors and retracted with a self-retaining iris hook to allow access to the anterior capsule and cataractous lens material. An evanescent, fibrotic ICE membrane was peeled from the surface of the anterior capsule. Capsulorhexis was performed with the assistance of indocyanine green (ICG). Phacoemulsification through a temporal corneal approach proceeded uneventfully. Following cortical cleanup and posterior capsule polishing, a capsular tension ring (Ophtec) placement achieved adequate bag stabilization and recentration a single-piece hydrophobic acrylic intraocular lens (IOL) (Alcon SA60AT) was implanted in the capsular bag. The wound was enlarged to approximately 4.0 mm. Two brown Ophtec type DE1 double-element iris prosthesis devices were then serially implanted in the capsular bag in front of the IOL (Figure 2), and the elements were then dialed orthogonally, establishing a complete iris diaphragm. A brown Ophtec fixation element was then placed to lock the DE1 pieces together (Figure 3). No manipulation or stretching of the atrophic remnant iris was attempted.
Figure 1. Preoperative photograph of the right eye showing the superonasally decentered pupil and 2 atrophic ICE melting holes. The crystalline lens is cataractous with posterior subcapsular changes and is decentered superiorly.
Figure 2. Correct insertion of iris device into the capsular bag is facilitated by identification of the capsulorhexis edge (arrow). Portions of the device already in the capsular bag are easily identified (asterisk) because of stained anterior capsule. An iris hook retracts the iris remnant to facilitate visibility.
2052
RESULTS
Postoperatively, the patient felt that the quality of her vision in that eye had improved considerably and that she was no longer troubled by photophobia or glare outdoors. The uncorrected visual acuity improved to 20/30 at 6 weeks of
J CATARACT REFRACT SURG - VOL 31, NOVEMBER 2005
TECHNIQUES: KHNG
Figure 3. Postoperative appearance showing the iris elements dialed orthogonally and secured with a locking ring.
follow-up, and the patient was pleased with both the functional and the cosmetic result. The iris prosthesis complex was well centered, and the IOL was in excellent position. Intraocular pressure remained in the midteens without medication, and the Baerveldt tube was in good position. DISCUSSION
Iris reconstruction in ICE syndrome is exceedingly difficult owing to the typically stiff and friable nature of the iris stroma. Accordingly, repair using sutures in these cases generally yields poor results. Although iris prostheses have been reported in ICE patients (K.J. Rosenthal, MD, presented at the AAO Annual Meeting, Anaheim, California, USA, 2003), the single-piece designs (Morcher, Ophtec) require a large incision (9.0 to 10.0 mm). In glaucoma patients, a small incision is a distinct advantage. Paired Morcher type 50-C devices can be inserted through a 3.5 mm incision but are only available in black PMMA, which is brittle3,4 and cosmetically less desirable in patients with all but the darkest irides. The iris prosthetic devices from Ophtec are available in 4 colors: light blue, light green, brown, and black. Unless the patient’s natural iris color is a very light blue, we have usually opted to implant the midbrown device because we believe it provides the best cosmetic result. The color intensities (saturation and brightness) of the light blue and light green implants may be too disparate from a darker fellow iris to prevent a distracting contrast. In contradistinction, the brown implants are often of a similar degree of intensity to a green or dark blue iris; they often look like congenital heterochromia and provide with satisfactory cosmesis. The dual elements of the IPS system do not completely fill the peripheral capsular bag in the quadrants oblique to
the elements’ long axes; however, the area of peripheral bag exposure creates 4 shallow triangular spaces, less than 1.0 mm at greatest radial dimension. Although the Morcher 50 series elements extend to the bag periphery for 360 degrees, the pupillary aperture varies with the element chosen (50-C, D, or E) and those with smaller apertures require progressively larger incisions. As in our patient, an ICE membrane of proliferating cells may exist over some or all of the anterior chamber structures, including the trabecular meshwork, iris, and lens capsule. It is important in these cases not to confuse this ICE membrane for the anterior capsule.5 Often the membrane can be peeled starting at an area of posterior synechias. It is vital not to mistake the ICE membrane for the capsule and inadvertently believe that a capsulorhexis has been created when it has not. In this case, ICG dye was used even though the cataract was not dense and a good red reflex was present. Our preference is to use capsule staining in cases in which zonular compromise exists or an opaque implant is to be placed in the capsular bag. Capsule staining facilitates identification and orientation of the capsular bag periphery and capsulorhexis margin in later steps of the procedure, when they may deviate from their native positions as lens material is removed. Capsule dye also aids in proper endocapsular placement of iris prosthetic devices because the capsule edge cannot be seen well with an opaque device preventing a red reflex. The stained capsule creates a green tinge over the surface of the device when the implant is placed below the anterior capsule leaflet. We believe that the routine use of capsule stain may lead to enhanced safety when multiple devices are to be placed in the bag and the success of the surgical outcome depends on the integrity of the anterior capsule rim and bag. Insertion of multipiece devices in the bag requires several gentle but dexterous manipulations in combination with a keen awareness of the location of the anterior capsulorhexis. The long-term stability of intracapsularly placed devices in eyes with questionably weakened zonules has yet to be established. The weight of additional hardware placed in the capsular bag may create stress on the zonules over time from normal saccade movements or, in particular, in patients with nystagmus. For cases in which iris repair is not a suitable option and a small incision is desirable, a multipiece iris device can provide a good cosmetic result and relief from the symptoms associated with loss of an intact iris diaphragm.
REFERENCES 1. Rosenthal KJ. Sutureless phacotrabeculectomy and insertion of an iris diaphragm ring in a patient with the Axenfeld-Reiger syndrome: first reported case. Video Cataract Refract Surg 1997; 13(2)
J CATARACT REFRACT SURG - VOL 31, NOVEMBER 2005
2053
TECHNIQUES: KHNG
2. Hermeking H. Iris prosthetic system. Video Cataract Refract Surg 1999; 15(4) 3. Burk SE, Da Mata AP, Snyder ME, et al. Prosthetic iris implantation for congenital, traumatic, or functional iris deficiencies. J Cataract Refract Surg 2001; 27:1732–1740
2054
4. Osher RH, Burk SE. Cataract surgery combined with implantation of an artificial iris. J Cataract Refract Surg 1999; 25:1540–1547 5. Azuara-Blanco A, Wilson RP, Eagle RC Jr, Rafferty PA. Pseudocapsulorrhexis in a patient with iridocorneal endothelial syndrome. Arch Ophthalmol 1999; 117:397–398
J CATARACT REFRACT SURG - VOL 31, NOVEMBER 2005