Ординатура / Офтальмология / Английские материалы / The Pediatric Glaucomas_Mandal, Netland_2006

Studies of trabeculectomy with adjunctive mitomycin-C in pediatric patients are summarized in Table 12.1.11–20 The success rate reported in these studies ranged from 48% to 95%, depending on the patient’s age, the definition of success, length of follow-up, and other factors. It is clear that trabeculectomy with mitomycin-C has a higher success rate than trabeculectomy alone in pediatric patients. However, complications were reported in these studies, including hypotony with shallow anterior chamber, choroidal detachment, retinal detachment, cataract, bleb leak, and bleb-related infection (blebitis and endophthalmitis). Sidoti and coworkers20 showed a high (17%) long-term incidence of bleb-related infection in children after trabeculectomy with mitomycin-C.

Late bleb-related ocular infection and vision loss may occur in children after trabeculectomy with mitomycin-C.21,22 These infections are characterized by abrupt onset, bleb

infiltration, and rapid progression (Fig. 12.2). In one report, Staphylococcus grew in three of three eyes that developed

bleb-related ocular infection.21 In another report, surgical technique in young patients using a limbus-based conjunctival flap was more likely to result in cystic bleb appearance

Figure 12.2 Late bleb-related infection after trabeculectomy with mitomycin-C. The patient developed blebitis and endophthalmitis associated with a bleb leak several years after trabeculectomy with mitomycin-C.

and bleb-related ocular infection compared with a fornix-based conjunctival flap.22 After trabeculectomy with mitomycin-C, patients develop thin-walled, avascular blebs, which may predispose patients to an increased incidence of late complications (Fig. 12.3). Life-long follow-up is required to periodically examine these eyes. The parents of children treated with mitomycin-C-augmented trabeculectomy should be instructed to report to the ophthalmologist on an emergency basis if the operated eye develops redness, discharge, decreased vision, or any other symptoms.

The optimal dosing and administration of mitomycin-C in children is yet unknown (Fig. 12.4). Since children are known to have more fibroblastic activity compared to young adults and elderly patients, most clinicians use a standard dose of mitomycin-C, similar to the concentration and exposure time used in elderly patients or young adults. The usual range of concentration used is from 0.2 to 0.4 mg/ml, with an exposure time of 2 to 4 minutes. In adults, no definite differences in efficacy or success rate have been identified in this dose range.23,24 Further information would be helpful about the effects of dosing and administration of mitomycin-C on efficacy and adverse effects in pediatric patients.

Despite achieving good results with the use of mitomycin- C with trabeculectomy, we do not recommend its use during primary surgery in children afflicted with congenital glaucomas. Adjunctive use of mitomycin-C is associated with potentially serious ocular complications and the long-term effects of mitomycin-C are not yet known. Additionally, conventional primary surgery such as goniotomy, trabeculotomy, or combined trabeculotomy–trabeculectomy has been very effective in this patient population. However, intraoperative application of mitomycin-C is a useful option in children with refractory congenital glaucoma with previously failed primary surgery. After trabeculectomy with mitomycin-C, children require periodic examination and the parents should be educated about the possible late complications.

C D

0.4 mg/ml, 4–5 min

0.4 mg/ml, 2–3 min

0.2 mg/ml, 4–5 min

0.2 mg/ml, 2–3 min

Figure 12.4 Surgical success with varying applications of mitomycin-C. In this series of 254 eyes with developmental glaucoma, surgical success was defined as postoperative intraocular pressure greater than 3 mmHg and less than 21 mmHg without additional medications or surgery, at least one year after surgery. Comparisons between these groups showed no statistically significant differences. From data in Al-Hazmi A, Zwaan J, Awad A, et al. Effectiveness and complications of mitomycin-C use during pediatric glaucoma surgery. Ophthalmology 1998; 105:1915–1920.

Glaucoma drainage implants

Glaucoma drainage implants are useful when other surgical treatments have a poor prognosis for success, prior conventional surgery fails, or when significant conjunctival scarring precludes filtration surgery (Fig. 12.5). Smaller sized drainage implants have been marketed for use in pediatric patients, but adult sized devices are commonly implanted. Available types of drainage implants may be characterized as open tube (non-restrictive) devices or valved (flow-restrictive) devices. Examples of open tube implants include the Molteno and Baerveldt implants, whereas the Krupin implant and the Ahmed Glaucoma Valve are flow-restrictive devices. The flowrestrictive devices are intended to reduce the incidence of

Figure 12.5 Glaucoma drainage implant tube in the anterior chamber of an 11-year-old with a history of congenital glaucoma. This child had failed primary surgery and had significant conjunctival scarring. There are Haab’s striae in the cornea.

complications associated with hypotony during the immediate postoperative period. Glaucoma drainage implants are most commonly placed in the superotemporal quadrant, but may be surgically positioned in any quadrant.

Studies of glaucoma drainage implants in pediatric patients are summarized in Table 12.2.25–42 The success rate reported in these studies ranged from 56% to 95%, depending on the patient age, the definition of success, length of follow-up, and other factors (Figs 12.6 and 12.7). Glaucoma drainage implants may be effective in controlling the intraocular pressure, even in pediatric patients who have failed previous glaucoma surgery. However, complications have been associated with glaucoma drainage implants in pediatric patients. Reported complications include hypotony with shallow anterior chamber and choroidal detachments, tube–cornea touch and corneal edema, obstructed tube, exposed tube or plate, endophthalmitis, and retinal detachment. Most of these complications did not affect outcomes, but a small proportion were associated with vision loss.

% Success

100

80

60

40

20

0

% Success

100

80

60

40

20

0

Figure 12.6 Percent success after Molteno and Baerveldt implants in pediatric patients. Success was defined as intraocular pressure of

21 mmHg or less without further surgical therapy. The overall success was 80%. Modified with permission from Netland PA, Walton DS. Glaucoma drainage implants in pediatric patients. Ophthalmic Surg 1993; 24:723–729 (reference 31).

Figure 12.7 Percent success after Ahmed Glaucoma Valve in pediatric patients. Success was defined as an average intraocular pressure less than 22 mmHg (or lowered by at least 20% from preoperative values in eyes with preoperative intraocular pressure less than 22 mmHg) and no additional glaucoma surgeries or visually devastating complications. The cumulative probability of success was 78% at 12 months. Data from Coleman AL, Smyth RJ, Wilson MR, Tam M. Initial clinical experience with the Ahmed Glaucoma Valve implant in pediatric patients. Arch Ophthalmol 1997; 115:186–191 (reference 34).

Figure 12.8 Mean intraocular pressure (mmHg) and number of medications after implantation of Ahmed Glaucoma Valve in pediatric patients with refractory glaucoma. By 3 months postoperatively, the intraocular pressure and number of medications had become stable. From data in Englert J, Freedman SF, Cox TA. The Ahmed Valve in refractory pediatric glaucoma. Am J Ophthalmol 1999; 127:34–42.

Postoperatively, patients often require adjunctive glaucoma medications and close monitoring for complications (Fig. 12.8). Iris creep around the tube insertion site may cause corectopia with drainage implants in children.43 Extraocular muscle imbalance has been reported after Baerveldt implant,44 but this may occur after any type of drainage implant. Conjunctival and even transcorneal45 tube erosions have been reported in children, which may lead to delayed endophthalmitis.46,47 Episodes of postoperative hypotony are commonly reported with open-tube implants, whereas the flow-resistive implants have reduced rate of hypotony in the immediate postoperative period.

Two-stage implantation of a glaucoma drainage device may be considered for eyes at high risk for complications due to hypotony.25,26 In the first stage, the plate is implanted and the tube is left under the conjunctiva near the limbus. A period of 4 to 6 weeks prior to the second stage allows a pseudocapsule to form, which provides some resistance to aqueous flow in the immediate postoperative period after tube insertion. In the second stage, the tube is inserted into the anterior chamber. This approach is most commonly used for open tube implants, such as the Molteno25,26 and Baerveldt48 implants, but may also be used for flow-resistive valves.

Glaucoma associated with Sturge–Weber syndrome may be due to isolated trabeculodysgenesis or to elevated episcleral venous pressure, which predisposes these patients to flat anterior chamber and choroidal detachment after glaucoma surgery. Goniotomy or trabeculotomy often fail, but these procedures are preferred as primary surgery, because of a lower complication rate compared with trabeculectomy.49 Glaucoma drainage implants have been helpful in patients with Sturge–Weber syndrome requiring additional surgical treatment. Satisfactory results have been reported using a two-stage Baerveldt implant48 or a single stage Ahmed Glaucoma Valve.50

If the intraocular pressure increases after glaucoma drainage implant, most clinicians will recommend adjunctive medical therapy. If adjunctive medical therapy fails to control the intraocular pressure, supplemental laser cyclophotocoagulation may be very useful.51 Another alternative is revision of the drainage implant, excising a portion of the pseudocapsule around the implant plate.52 This approach is similar in concept to needling of encapsulated blebs, and has a similar success rate. Additional glaucoma drainage devices may be implanted in an unused quadrant, which may control the intraocular pressure.53,54

In the 10–20% of patients who fail initial surgery for developmental glaucoma, the clinician often chooses trabeculectomy with mitomycin-C or a drainage implant as a subsequent surgical treatment. In one study comparing outcomes of trabeculectomy with mitomycin-C and glaucoma drainage implant, the success rate was higher after drainage implant,55 whereas another study found similar success rates after these two procedures.56 Both procedures are useful in patients with developmental glaucoma that is refractory to initial surgical treatment. We often proceed to trabeculectomy with mitomycin-C after failed primary surgery and, if this procedure is unsuccessful, drainage implant is indicated. However, the exact order of treatment is dependent on individual surgeon preference at this time.

Cyclodestructive procedures

After initial and secondary surgical treatments fail to control the intraocular pressure, a cyclodestructive procedure may be considered. In some instances, these treatments may be performed as adjunctive therapy or as primary therapy. Cyclodestructive procedures cause damage to the ciliary epithelium, reduce aqueous production, and thereby lower the intraocular pressure. The most commonly performed procedures include cyclocryotherapy and cyclophotocoagulation. When available, cyclophotocoagulation is usually the preferred procedure because it is associated with less postoperative inflammation and less discomfort for the patient compared with cyclocryotherapy.

In cyclodestructive procedures, the amount of treatment required to achieve the desired degree of intraocular pressure reduction may be difficult to titrate.57 Retreatments are often necessary after cyclodestructive procedures. Perhaps most importantly, these procedures may be associated with visionthreatening complications. The risk of hypotony, vision loss, and even phthisis is substantial. Parents should be informed about these possibilities and patients should be monitored for these problems.

In cyclocryotherapy, a probe is applied just posterior to the limbus to freeze the ciliary body and ciliary epithelium. Al Faran and coworkers58 reported a 30% success rate, with no difference between the success rates in eyes that been treated with other glaucoma procedures prior to cyclocryotherapy compared with eyes with no previous glaucoma surgery. Wagle and coworkers59 reported 44% success after cyclocryotherapy in refractory pediatric glaucoma, requiring an

The life-table analysis showed cumulative probability of success declining to 36% with extended follow-up. Modified with permission from Wagle NS, Freedman SF, Buckley EG, Davis JS, Biglan AW. Long-term outcome of cyclocryotherapy for refractory pediatric glaucoma. Ophthalmology 1998; 105:1921–1927.

Figure 12.10 Cyclophotocoagulation. The diode laser handpiece attachment from one manufacturer is shown. The ciliary body is treated with the laser, which reduces aqueous production. Modified from figure provided courtesy of Iris Medical.

average of 4.1 treatments for successful eyes (Fig. 12.9). Devastating complications occurred even more frequently among eyes with aniridia compared with other eyes (50% and 11%, respectively). Vision-threatening complications include retinal detachment, hypotony, and phthisis.

Cyclophotocoagulation can be performed with a variety of lasers, including the neodymium:yttrium–aluminum–garnet (Nd:YAG), 810 nm diode, and krypton laser (Fig. 12.10). Although non-contact procedures have been described, the procedure is usually performed with a specially designed contact probe, which is applied near the limbus over the ciliary body. In children, the procedure is usually performed under general anesthesia in the supine position. Table 12.3 summarizes the results of studies of cyclophotocoagulation in pediatric patients.60–66 In general, success rates with a single treatment are low, retreatment is often required, and complications are perhaps less frequent but are similar to those found after cyclocryotherapy.

Cyclophotocoagulation may be performed with an endolaser and an endoscope, although this approach is not widely available. The procedure requires intraocular surgery, but the laser energy is delivered more precisely to the target tissue.67–70 In a study of 36 eyes, Neely and Plager69 reported a success rate of the initial procedure of 34% (intraocular pressure ) 21 mmHg, with or without adjunctive glaucoma medications), which increased to 43% after retreatments. At this time, there is no clear benefit of this procedure compared with contact transscleral cyclophotocoagulation.

Cyclodestructive procedures are usually reserved for children who have not responded to other surgical treatments for intractable elevation of intraocular pressure. These procedures have limited success rates, often require retreatment, and may be associated with vision-threatening complications. Some clinicians advocate cyclodestructive procedures

early in the surgical treatment regimen, while most reserve cycloablation until after other primary and secondary treatments have failed. Supplemental sub-maximal or full treatment with cyclophotocoagulation may be useful if the intraocular pressure is uncontrolled despite glaucoma drainage implants or other glaucoma surgical treatments.51

Laser therapy

With the exception of laser cyclophotocoagulation, there is a limited role for laser therapy in the treatment of pediatric glaucomas. Although angle-closure may occur in children,71–74 surgical iridectomy is usually performed. Children require general anesthesia for both laser and surgical iridectomy, and the logistics of laser treatment may be difficult. Laser trabeculoplasty is the most commonly performed laser procedure for open-angle glaucoma in adults, but this procedure is not useful in children. Nd:YAG goniopuncture has been tried in young patients;75,76 however, the long-term success is poor.

Conclusions

Patients with congenital glaucoma may fail the initial surgical procedure, and some pediatric patients have glaucomas with a poor prognosis for the success of initial goniotomy or trabeculotomy. Trabeculectomy alone has a poor long-term success rate, but trabeculectomy with adjunctive antifibrosis drug (e.g., mitomycin-C) has a satisfactory success rate. Patients, however, may develop late complications and require continued monitoring for problems such as bleb leak and bleb-related infections. Glaucoma drainage device implantation is another useful option in these patients. Patients often require adjunctive glaucoma medications and may develop complications, most of which are not visionthreatening. Cyclodestructive procedures may be useful, especially in children with elevated intraocular pressure despite previous trabeculectomy or glaucoma drainage implant.

References

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44.Smith SL, Starita RJ, Fellman RL, Lynn JR. Early clinical experience with the Baerveldt 350-mm2 glaucoma implant and associated extraocular muscle imbalance. Ophthalmology 1993; 100:914–918.

45.Al-Torbak A, Edward DP. Transcorneal tube erosion of an Ahmed valve implant in a child. Arch Ophthalmol 2001; 119:1558–1559.

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Introduction

Penetrating keratoplasty in children with congenital glaucoma

Timing of glaucoma surgery

Conclusion

Introduction

Before the 1970s, there was considerable reluctance to perform penetrating keratoplasty in children. Since that time, reports of successful penetrating keratoplasty in the pediatric age group have appeared. These reports demonstrate that, with modern surgical techniques, corneal opacities can be removed and clear grafts can be maintained in many children. During the last four decades, the age at which a reasonable degree of success can be achieved has decreased from adolescence to young childhood to infancy. However, corneal edema or scarring from developmental glaucoma is a rare indication for penetrating keratoplasty in children. The efficacy of corneal transplantation in infants with corneal opacity secondary to developmental glaucoma has not been established.

The aim of this chapter is to provide an overview of penetrating keratoplasty in children with developmental glaucoma. We summarize here the analysis of results, identify the variables that influence the surgical outcome, and offer recommendations for the management of children with corneal opacities secondary to the developmental glaucomas.

Penetrating keratoplasty in children with congenital glaucoma

The graft survival and the development of useful vision after penetrating keratoplasty for pediatric congenital glaucoma has varied significantly in the literature. In an early case report, Waring and Laibson1 reported one infant with congenital glaucoma associated with hypertrophic vascularized corneal opacity who had ‘travel vision’ in one eye after undergoing three grafts in two eyes. The authors recommended early keratoplasty in patients with bilateral congenital opacities, but did not recommend keratoplasty in children with unilateral corneal opacities.

Schanzlin and coworkers2 reported a child with congenital glaucoma, bilateral sclerocornea, and multiple congenital anomalies. During the first week of life, the patient had undergone bilateral trabeculotomy. This procedure initially

controlled the intraocular pressure, but eventually the tension was elevated in both eyes. Subsequently, the patient underwent bilateral full-thickness filtering surgery at the second and third months, respectively. When the patient was 6 months old, a 6.5-mm penetrating keratoplasty was performed on the right eye. Intraoperatively, the patient was found to have aniridia, and the lens was adherent to the posterior surface of the cornea, necessitating extracapsular removal of the lens. The graft remained transparent for eight months and the patient, fitted with an aphakic soft contact lens, was able to follow objects. At 8 months postoperatively, an epithelial defect developed that healed after one month, leaving a 2-mm diameter superficial central opacity within an otherwise transparent graft.

Stulting and colleagues3 retrospectively studied 91 patients, 14 years of age or less, who had 152 penetrating keratoplasties in 107 eyes, with an average follow-up of 30 months. In this series, there were six eyes with congenital glaucoma and corneal edema. Overall, the graft survival rate at 12 months ranged from 60% among congenitally opacified eyes to 73% among those with acquired non-traumatic disease. The survival of the grafts in the congenital glaucoma group was not separately analyzed.

Frucht-Pery and coworkers4 reported corneal transplantation of congenitally opaque corneas in three children with buphthalmos. The eyes were treated initially with cyclocryotherapy, one application in one eye and two applications in two eyes. The size of the eyes decreased during the first two weeks postoperatively. Subsequent corneal transplantation improved vision in each eye, with a visual acuity of 20/400 in one child and formed images in two infants.

Huang and colleagues5 reported their experience with eight consecutive penetrating keratoplasties performed in adults with a history of congenital glaucoma. Six grafts remained clear and visual acuity was improved in five eyes (63%) after penetrating keratoplasty. Postoperative visual acuity was 20/40 (two patients), 20/100 to 20/400 (four patients), counting fingers (one patient) and hand motions (one patient). The most common surgical complication was postoperative elevation of intraocular pressure, which occurred in all the cases (8/8 eyes). The elevated intraocular pressure required treatment with permanent augmentation of glaucoma medications in seven eyes (88%) and glaucoma surgery in four eyes (50%). Two eyes (25%) developed corneal graft failure, one from immune rejection and the other from severe postoperative glaucoma treated with cyclocryotherapy. In view of these complications and the multiple impediments to

good postoperative vision, the authors concluded that penetrating keratoplasty be reserved for patients with severe visual disability whose preoperative glaucoma is wellcontrolled.

Cowden6 analyzed the results of keratoplasty performed in 50 children, with age ranging from 2 months to 14 years, who underwent 66 penetrating keratoplasties. He found that congenital glaucoma patients had the highest percentage of clear grafts (100% in seven cases) compared with any other group of pediatric patients after corneal transplantation.

Erlich and coworkers7 reported their experience with corneal transplantation in infants, children, and young adults performed at the Toronto Hospital for Sick Children between 1979 and 1988. Eighty-five penetrating keratoplasty procedures were performed in 54 patients with age ranging from 1 month to 18 years. Thirteen penetrating keratoplasty procedures were performed in eight patients with congenital glaucoma. Of these eight patients, five patients (62%) required two procedures. The average age at the time of the first procedure was 22.8 months (range from 10 months to 11.7 years). In patients with a history of congenital glaucoma, none of the grafts were clear after the average follow-up period of 16.6 months (range from 3 months to 4 years). The outcome was poor in patients with congenital glaucoma; however, the authors recommended that penetrating keratoplasty may be performed in children with Peters anomaly, herpes simplex keratitis, corneal dystrophy, or traumatic corneal scarring (Fig. 13.1).

Ariyasu and coworkers8 retrospectively reviewed the results of nine penetrating keratoplasties performed in eight eyes of six children who had multiple risk factors for poor prognosis. The risk factors included age less than 2 years at the time of grafting, uncontrolled glaucoma, concurrent lensectomy, retinal or glaucoma surgery, aphakia, and acute perforation. Six of the nine grafts (67%) remained clear during a mean follow-up of 24 months (30 months follow-up in eyes with clear grafts). Development of ambulatory vision or better occurred in six of eight (75%) eyes after corneal transplantation and treatment of refractive errors and amblyopia. Graft failure occurred in three eyes: two from graft failure, and one

Figure 13.1 Herpetic keratouveitis associated with elevated intraocular pressure in an adolescent patient. This patient maintained a clear graft, although filtration surgery failed to control the intraocular pressure. A glaucoma drainage implant was successful in controlling the intraocular pressure.

from graft rejection. Complications included one case of total retinal detachment, one case of keratitis due to Streptococcus pneumoniae, and three cases of elevated intraocular pressure

requiring further glaucoma surgery. The authors concluded that useful vision can be achieved after penetrating keratoplasty even in some high-risk infants with congenital glaucoma.

Dana and coworkers9 reported the results of a multicenter study to delineate the indications for and outcome of pediatric keratoplasty. The authors retrospectively studied 164 grafts in 131 eyes of 108 children younger than 12 years of age, with an average follow-up of 45 months. This series includes 12 penetrating keratoplasties in eight eyes of six children with congenital glaucoma. The graft survival of the congenital glaucoma group was not separately analyzed, but the 12 months survival rate was 80% for eyes with congenital opacification compared with 76% for those with acquired non-traumatic disease.

Frueh and Brown10 studied 58 eyes of infants and children with congenital corneal opacities who were treated with penetrating keratoplasty. Only two eyes in this series had congenital glaucoma. The probability of maintaining a clear graft was 75% at one year and 58% at two years for the entire group, and 23 eyes had to be regrafted between 2 weeks and 110 months postoperatively. A case report by Zacharia et al11 described a clear graft at 15 months of age after simultaneous treatment with penetrating keratoplasty and valved glaucoma drainage implant to treat congenital glaucoma with severe corneal scarring. The authors suggested that combined glaucoma and corneal treatment may improve long-term graft survival.

The success of penetrating keratoplasty in children with various corneal abnormalities was reported by Aasuri and coworkers.12 Clear grafts were achieved in 30 (64%) of 47 eyes with congenital opacities, with average follow-up of 1.3 years. Most of the graft failures occurred during the first 26 weeks after surgery. Poor graft survival was correlated with age younger than 5 years. Most grafts failed due to allograft rejection (42%), infectious keratitis (27%), or secondary glaucoma (13%). Although satisfactory anatomic outcomes were achieved, the visual outcomes were poor, suggesting the importance of the timing of surgery, amblyopia therapy, and other factors.

Endothelial decompensation due to congenital glaucoma is a rare indication for penetrating keratoplasty in adults (Fig. 13.2). Toker and co-workers13 identified 13 adult and three pediatric patients who underwent penetrating keratoplasty with a previous diagnosis of congenital glaucoma from a total of 3663 records of corneal transplantations. At the end of follow-up, 75% of patients with a history of congenital glaucoma had clear grafts, although 45% required regrafting. The final postoperative visual acuity was improved in 70% of eyes. Similarly, Ramchandani and co-workers14 identified nine eyes in adults with a history of congenital glaucoma, treated with glaucoma surgery earlier in life. The age range of the patients was from 27 to 71 years at the time of surgery, with average follow-up of 28 months. Two patients (22%)

developed graft failure at 15 and 41 months postoperatively due to elevated intraocular pressure after penetrating keratoplasty. Final visual acuity was improved in five patients, the same in three patients, and worse in one patient.

In aniridia patients, corneal opacification may be progressive, with an onset later in life. Pannus formation and aniridic keratopathy responds poorly to penetrating keratoplasty alone. Keratolimbal allograft (limbal stem cell transplantation) may stabilize the ocular surface and increase corneal transplant graft survival.15 Surgical treatment of elevated intraocular pressure may be required before or after keratoplasty (Fig. 13.3).

Timing of glaucoma surgery

In general, the intraocular pressure is stabilized in the normal range prior to penetrating keratoplasty. Because of the corneal opacity, initial surgical treatment is most commonly trabeculotomy rather than goniotomy. When primary surgery fails, other glaucoma treatments usually are performed prior to penetrating keratoplasty. However, combined penetrating keratoplasty and trabeculectomy with mitomycin C have been performed at the same setting.16 Penetrating keratoplasty has also been performed with the Ahmed Glaucoma Valve as a combined procedure.17

Conclusion

It has not been clearly established whether corneal transplantation is indicated in the pediatric patient with a corneal opacity due to congenital glaucoma, especially in patients with unilateral corneal opacities. The results from clinical case series reported in the literature have varied widely, although anatomic success may be improving. It does appear, however, that the prognosis is guarded for penetrating keratoplasty in this group of patients while there is a possibility of improvement of the vision in some patients. The optimal timing for surgery is not known. Although the prognosis is variable and uncertain, patients with bilateral corneal opacities are candidates for penetrating keratoplasty.

B

Figure 13.3 An adult aniridia patient with aniridic keratopathy and pannus formation (A). The appearance after keratolimbal allograft (limbal stem cell transplant) and penetrating keratoplasty (B) with a clear graft. The eye is aphakic and has been treated with glaucoma drainage implant for elevated intraocular pressure.

References

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