Ophthalmic Pearls

GLAUCOMA

Aphakic and Pseudophakic After Congenital Surgery

namratha turlapati, md, and sarwat salim, md, facs edited by sharon fekrat, md, and ingrid u. scott, md, mph

laucoma associated with Risk Factors 1 aphakia and pseudophakia Glaucoma may occur even after an un- is one of the most common complicated lensectomy for congenital complications of surgery cataract. However, several risk factors for .1 have been identified, including surgery GAlthough the underlying mechanism in the first year of life, microcornea remains unclear, it is thought to be (corneal diameter less than 10 mm), multifactorial in origin. Diagnosis re- other ocular abnormalities, certain lies on clinical signs, such as elevated types of cataract (nuclear sclerotic and intraocular pressure (IOP) and optic persistent hyperplastic primary vitre- nerve head cupping, as children are ous), retained proteins, and a his- often unable to perform a visual field tory of secondary membrane surgery.2,4 DRAINAGE IMPLANT. Baerveldt device examination. However, because it is Although some investigators have in aphakic eye of young patient with difficult to obtain a good reported a lower rate of glaucoma in glaucoma secondary to lensectomy. examination on a child in the office, eyes implanted with an intraocular (See Fig. 2 for more details.) the diagnosis can often be missed or lens (IOL), there may be a selection confused with . bias in terms of the children chosen (For tips on measuring IOP in chil- for IOL implantation that confounds visual development.6 dren, see the Clinical Update on page aphakia as a risk factor.3 The recent Although anatomic abnormalities 43 of this issue.) 5-year follow-up from the randomized can complicate congenital cataract Furthermore, glaucoma may pre- controlled Infant Aphakia Treatment surgery, modern instrumentation and sent years after the ; Study (IATS) did not find any signifi- techniques have decreased rates of pre- thus, long-term surveillance is essen- cant differences in glaucoma-related viously common unfavorable surgical tial for accurate diagnosis and timely adverse events between patients im- outcomes, such as retained lens frag- intervention. This article reviews epi- planted with an IOL and those left ments and cortex opacification, as well demiology, risk factors, mechanisms, aphakic.5 as the need for secondary surgery for and treatment for glaucoma secondary Younger age at the time of cataract posterior capsule opacification.3 to pediatric cataract surgery. surgery is one of the few glaucoma risk factors under a surgeon’s control. Mechanisms Epidemiology However, the current literature is Angle-closure glaucoma. When earlier The prevalence of glaucoma after pedi- conflicting with regard to the opti- needling techniques were used to re- atric cataract surgery is reported to be mal timing for lensectomy. Although move congenital , angle- as high as 41%,1 depending on length delaying surgery might reduce sub- closure glaucoma was the most com- of follow-up.2 The reported time to sequent glaucoma risk, the physi- mon type seen in this setting. Mecha- diagnosis after surgery averages 6 to 7 cian must also take into account the nisms included swelling of lens mate- years.1,3 For children who have under- deleterious effect of delays on visual rial, fibrinous material blocking the gone lensectomy, both the diagnosis of deprivation and .3 In unilat- , and vitreous prolapse into the secondary glaucoma and delayed glau- eral cases, many experts recommend anterior chamber with pupillary block. coma presentation are associated with performing congenital cataract surgery Advances in surgical techniques for 2 sharon freedman, f. md a worse visual prognosis. at 4 to 6 weeks of age to avoid impaired aspiration, posterior capsulotomy, and

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A COMPLEX CASE. Right eye of a teen- 2 cataract surgery is better than that aged boy who was born with microcornea observed with primary congenital and cataracts and lost his left eye to glaucoma. A review by Asrani and complications of after Wilensky reported that medications glaucoma surgery in infancy. He devel- alone controlled IOP in 21 of 33 eyes 8 oped glaucoma in his remaining eye in (63.3%). early childhood. Choice of medication. Commonly Initially managed with glaucoma medi- used drugs include topical beta block- cations, he later required a drainage im- ers, carbonic anhydrase inhibitors, 3 plant. A 250-mm Baerveldt device was and pilocarpine. Because of the risk of implanted in the pars plana (in the su- retinal detachment with pilocarpine, perotemporal area at about 10 o’clock), especially in the setting of aphakia, and a pars plana vitrectomy was per- retinal evaluation should be routinely formed to help keep the tube away from the and to avoid vitreous block- performed. age of the tube or traction on the . (This procedure was performed jointly Prostaglandin analogues generally with a vitreoretinal surgeon familiar with pediatric cases.) The irregular pupil was do not work well in children. Alpha- present before surgery but worsened afterward, and he required a small second adrenergic agonists, such as brimo- surgery to remove a portion of the that was blocking the tip of the tube, nidine, are associated with extreme which was placed underneath the iris. fatigue and somnolence in children 3 This patient’s IOP is now controlled with 1 daily glaucoma drop, and he has and should be avoided. Although ac- maintained 20/20 vision for more than 5 years after surgery. etazolamide can be used in children, Some patients with congenital cataracts or other ocular abnormalities may it is not an ideal long-term medication have a short axial length. In such cases, alterations in technique may be needed due to renal and hepatic side effects 3 to ensure that the back edge of the drainage reservoir is far enough away from and growth suppression. the optic nerve. —Photographs and case study courtesy of Sharon F. Freedman, MD For cases presenting with concomi- tant inflammation, anti-inflammatory anterior vitrectomy have now largely cility and lead to elevated IOP. agents may be combined with anti- reduced the occurrence of these glau- The mechanical etiology points to glaucoma treatment. comas.3 barotrauma from the surgery and re- Vajpayee and colleagues have also duced traction on the trabecular mesh- Surgical Treatment reported pupillary-block glaucoma af- work from loose zonular fibers after When medical management fails, sur- ter IOL implantation in children.7 Al- lens extraction. gical intervention is necessary. Surgical though the exact pathogenesis remains The chemical-based theory suggests options include angle surgery, trabecu- unclear, potential mechanisms include that contact between the trabecular lectomy with or without antifibrotics, formation of synechiae between the meshwork and the vitreous, lens par- glaucoma drainage devices (valved or IOL and iris or anterior capsule, vitre- ticles, or inflammatory cells is likely nonvalved), and cyclodestructive pro- ous prolapse into the anterior chamber toxic to the drainage angle. cedures. Laser trabeculoplasty has not from zonular or posterior capsule com­ In addition, steroid medications been found to be effective for manag- promise, and alterations in the ana- used in connection with cataract ing OAG in children. tomic structures of the drainage angle. surgery are another cause of IOP in- Angle surgery. These procedures, Tactics to reduce the risk of angle- crease. Children are more susceptible which include trabeculotomy or goni- closure glaucoma include postoperative to steroid-induced ocular hyperten- otomy, have a variable success rate in use of steroids and mydriatics and sion, which often has a rapid onset glaucoma associated with aphakia or . and is more aggressive than in adults. pseudophakia when compared with Open-angle glaucoma. Open-angle Because inflammation is increased and primary congenital glaucoma; success glaucoma (OAG) is now the most com- of longer duration after pediatric cata- rates have been reported between 16% mon type of glaucoma occurring after ract surgery, patients receiving steroids and 57%.3 congenital cataract surgery. The recent must be monitored closely in the post- Trabeculectomy. Historically, tra- IATS reported that 19 of 20 eyes that operative period.4 beculectomy has been the most com- developed glaucoma had OAG.5 As monly performed procedure, with re- noted above, it often has delayed onset Medical Treatment ported success rates ranging from 50% years after lensectomy.4 Although the The first-line treatment for glaucoma to 85%.9 A thick Tenon’s capsule and a exact etiology remains uncertain, me- associated with pediatric aphakia or more exuberant healing response limit chanical and chemical theories have pseudophakia is usually medication. this surgery’s success in children. been postulated.1 Both mechanisms The response to medical treatment Use of mitomycin C increases the eventually reduce aqueous outflow fa- for glaucoma secondary to pediatric success rates but is associated with a

64 november 2015 Ophthalmic Pearls higher risk of bleb-related infection. Key Points The infection rate is particularly high Glaucoma associated with aphakia or in children due to limitations in hy- pseudophakia is a common complica- Write for Us! giene control.3 As an alternative, the tion following lensectomy for congeni- antifibrotic agent 5-fluorouracil used tal cataract. Diagnosis relies on clinical postoperatively has potentially fewer examination and ongoing follow-up, side effects. However, it often requires as the majority of cases are diagnosed frequent subconjunctival injections many years after surgery. Although Got Pearls? under general anesthesia and, thus, is open-angle glaucoma accounts for the Share your knowledge with your not a practical approach in this popu- large majority of cases, angle-closure colleagues! Ophthalmic Pearls 3,9 lation. glaucoma may occur infrequently. articles provide a literature re- Drainage devices. Another option, Medical management is the first- view and offer helpful tips on glaucoma drainage devices, can avoid line treatment and has a high success disease management or proce- the complications related to the use of rate. If glaucoma drugs fail, filtering dures in widespread use. antifibrotic agents in filtering surgery. surgery with antifibrotic agents and Success rates for valved (e.g., Ahmed) drainage implants have both proved Are you a resident? and nonvalved (e.g., Baerveldt) de- effective in lowering IOP; however, Authorship of an Ophthalmic vices have been reported between 44% each has specific complications that re- Pearls will satisfy the RRC and 87%. It is difficult to make com- quire close follow-up. Amblyopia is the requirements for resident parisons among these studies, in part major cause of vision loss in children scholarly activity. because some were conducted with ad- with unilateral cataract or glaucoma. ditional topical medications and some With early recognition and successful without, and different definitions of management of glaucoma, children 1 success were used.3 can achieve good visual potential.4 ■ 2 Complications associated with drainage devices include hypotony, 1 Asrani S et al. J AAPOS. 2000;4(1):33-39. 3 choroidal effusion, tube exposure, mo- 2 Chen TC et al. Arch Ophthalmol. 2004;122 tility disturbances, and endophthalmi- (12):1819-1825. tis.3 Prevention of vitreous incarcera- 3 Baily C et al. J Clin Exper Ophthalmol. 2012; 4 tion in the tube is important. 3(1):203. doi:10.4172/2155-9570.1000203. Although higher success rates and 4 Whitman MC et al. Semin Ophthalmol. better side effect profiles have been re- 2014;29(5-6):414-420. 5 ported for glaucoma drainage devices 5 Freedman SF et al. JAMA Ophthalmol. than for trabeculectomy, a head-to- 2015;133(8):907-914. head analysis of the long-term out- 6 Chen TC et al. Trans Am Ophthalmol Soc. HOW TO WRITE AN OPHTHALMIC comes of these surgical interventions 2006;104:241-251. PEARLS ARTICLE will be necessary for definitive com- 7 Vajpayee RB et al. Am J Ophthalmol. 1991; 1. Come up with a topic, and e- parison. In aphakic patients who use 111(6):715-718. mail Peggy Denny (pdenny@aao. contact lenses for correction, glaucoma 8 Asrani S et al. Ophthalmology. 1995;102(6): org) to clear it before writing. drainage devices may be preferable to 863-867. 2. Medical students, residents, filtering surgery to reduce the risk of 9 in aphakia and pseudophakic and fellows: Team up with a infection. after congenital cataract surgery. In: Mandal faculty member who can provide Other surgical therapies. Cycloab- AK, Netland PA. The Pediatric Glaucomas. pearls from experience. lative procedures, such as cyclocryo- Oxford, U.K.: Butterworth-Heinemann; 2006. 3. Send at least one photo or therapy and cyclophotocoagulation, illustration. are useful in refractory cases, but Dr. Turlapati is a fellow in pediatric ophthal- 4. Use subheadings to help success rates are low over the long mology at Children’s National Medical Center readers easily navigate your term. Often, these procedures require in Washington, DC. Dr. Salim is professor 1,500-word article. multiple treatments and carry the risk of ophthalmology and chief of the glaucoma 5. Keep references to five or of serious vision-threatening compli- service at Medical College of Wisconsin in fewer, if possible. cations. Endocyclophotocoagulation, Milwaukee. Dr. Freedman is professor of oph- a more targeted treatment, may reduce thalmology and chief of the pediatric ophthal- the risk of hypotony.3 mology and division at Duke Eye SUBMISSIONS In cases of pseudophakic pupillary Center in Durham, N.C. Relevant financial Email your manuscript and art to block glaucoma, Nd:YAG iridotomy disclosures: None. For full disclosures, view [email protected]. has been reported to be successful.7 this article at www.eyenet.org.

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