Ophthalmic Pearls EXTRA

GLAUCOMA CONTENT AVAILABLE

Ectropion Uveae and Secondary

by john prenshaw, MD, and sarwat salim, md, facs edited by ingrid u. scott, md, mph, and sharon fekrat, md

1 ctropion uveae (EU) is de- tion. The hyperplasia is thought to be 1 fined by the presence of induced by a primordial endothelium, pigment epithelium on the an embryological remnant that fails to anterior surface of the iris. fully regress in the anterior chamber.2 Although EU typically is an This anomaly may be caused by a late acquiredE condition, it may occur as an developmental arrest of neural crest isolated congenital anomaly or in as- tissue in utero.1 sociation with systemic such Typical clinical findings include a as neurofibromatosis. glassy, smooth, cryptless iris surface, This review focuses on various iris stromal atrophy, proliferation of types of EU, with an emphasis on sec- iris pigment epithelium onto the ante- ondary glaucoma and its management. rior surface of the iris, and glaucoma. The is typically round and reac- Overview tive to light but may grossly appear Acquired. Acquired EU is often ob- irregular because of the abnormal iris CONGENITAL ECTROPION UVEAE. A view served with neovascularization of the pigment epithelium. The affected eye of CEU in the patient’s eye. iris and neovascular glaucoma; it also may exhibit mild to moderate may be associated with any inflamma- with good levator function. This find- the time of diagnosis ranged from 7 tory, ischemic, or neoplastic process ing is most likely related to the neural months to 42 years. The variation in involving the iris. crest cell origin of Mueller’s muscle. onset and severity of glaucoma may be This type of ectropion is commonly Systemic diseases. Although EU explained by the degree of arrest in iris progressive. A contracting fibrovascu- has been associated with several migration and subsequent trabecular lar membrane with atrophy of the iris systemic diseases, including neurofi- meshwork malformation. The amount stroma causes a tractional curling of bromatosis, facial hemiatrophy, and of endothelial remnant has also been the posterior pigment epithelium, iris Prader-Willi syndrome, the condition shown to vary but does not seem to be sphincter muscle, and stroma around is most often associated with neurofi- associated with glaucoma severity.2 the pupillary margin. bromatosis-1, or NF1 (see below). Findings. In eyes with CEU, goni- Congenital. Congenital EU (CEU) oscopy typically reveals an anterior is a rare disorder, and epidemiological Secondary Glaucoma and CEU iris insertion, which in some cases ex- data on incidence are scarce. Although Glaucoma is a frequent complication tends almost to Schwalbe’s line.1,3 The bilateral cases have been reported, the of CEU. In one report, glaucoma oc- failed posterior migration of the iris is is usually unilateral. In addi- curred in seven of eight cases of CEU.3 thought to cause drainage angle dys- tion, it tends to be nonprogressive. In another, glaucoma was found in genesis and incomplete formation of CEU is characterized by iris pig- nine of 10 patients with CEU, and the trabecular meshwork and Schlemm’s ment hyperplasia onto the anterior 10th patient was expected to ultimately canal.2 This dysgenesis is the primary surface of the iris around the pupillary develop glaucoma.1 mechanism of glaucoma in CEU. margin (Fig. 1). In contrast to acquired Age of onset. In the studies cited Differential diagnosis. The differ- EU, the iris sphincter muscle and stro- above, glaucoma was most commonly ential diagnosis of a patient with CEU ma are not affected in CEU and are not diagnosed in childhood or early and glaucoma includes Axenfeld-Rieg-

sarwat salim, md, facs everted on histopathologic examina- adolescence, but the patients’ ages at er syndrome (ARS) and iridocorneal

eyenet 47 Ophthalmic Pearls endothelial (ICE) syndrome. cations.1 In another study, six of seven diagnosed with EU. Of the 43 patients • ARS, like CEU, is associated with patients required trabeculectomy.3 who had NF1 and orbital involvement an arrest in neural crest tissue devel- Follow-up data on treatment suc- but no glaucoma, only four had EU, opment. Findings include a high iris cess rates over an extended period in and these eyes had partial angle clo- insertion, angle dysgenesis, EU, and patients with CEU-associated glauco- sure.8 In another study, all five patients glaucoma. However, the ectropion may ma are not available. However, data are with orbitofacial NF1 and glaucoma manifest later in ARS and tends to be available for other types of secondary demonstrated histopathological EU.7 progressive. Furthermore, the syn- pediatric . Trabeculectomy The pathogenesis of glaucoma in drome is associated with other clinical alone has a 30 to 35 percent success NF1 is likely multifactorial, involving findings such as posterior embryo- rate over extended follow-up. With the infiltration of the anterior chamber toxon, iris atrophy, and corectopia or use of the antimetabolite mitomycin C angle by neurofibromas, neurofibro- polycoria. Facial abnormalities—such (MMC), the procedure is 52 to 95 per- matous thickening of the as maxillary hypoplasia and dental cent successful at lowering IOP, with a and leading to angle closure, defects—may be noted. ARS is autoso- 60 percent success rate at two years. A secondary angle closure by anterior mal dominant, frequently hereditary, 7 to 14 percent risk of late postopera- synechiae, and developmental angle and bilateral. Glaucoma is noted in 50 tive , however, is as- anomalies.8 percent of patients with ARS.4 sociated with this procedure. Visual prognosis is poor in these • ICE syndrome is typically unilat- Glaucoma drainage devices have patients. In the study by Morales et al., eral and is an acquired condition (se- a 44 to 95 percent success rate, with all of the patients with NF1 and glau- rologic studies indicate an association 60 to 65 percent success at two years.4 coma who were able to give a reliable with herpes simplex virus or Epstein- The risk of endophthalmitis is lower visual acuity level were either legally or Barr virus infection). Although ICE with drainage implants, but adjunctive totally blind, and one-third required syndrome predominantly affects medical therapy is often necessary to either enucleation or evisceration of middle-aged women, an occurrence in maintain IOP control as opposed to the affected eye.8 a child has been reported. In ICE syn- trabeculectomy with MMC. In addi- Treatment strategies for glaucoma drome, the altered corneal endothelial tion, complications that require surgi- in patients with NF1 and EU are simi- cells grow over the iris and trabecular cal intervention may occur, including lar to those discussed above for sec- meshwork and result in formation of a tube- touch, implant exposure, ondary pediatric glaucomas. n cellular membrane. The contraction of tube blockage, or dislocation. this membrane leads to formation of In refractory cases, cyclodestruc- 1 Dowling JL Jr et al. . 1985; peripheral anterior synechiae and sec- tive procedures may become necessary, 92(7):912-921. ondary angle-closure glaucoma.5 but these procedures may have limited 2 Wilson ME. J Pediatr Ophthalmol Strabis- Treatment. Treatment of glaucoma success and a high complication rate.4 mus. 1990;27(1):48-55. in patients with CEU usually requires 3 Ritch R et al. Ophthalmology. 1984;91(4): surgery, although medical manage- Ectropion Uveae and NF1 326-331. ment may be attempted initially. Vi- Glaucoma and NF1. Glaucoma in pa- 4 Beck AD. Ophthalmol Clin North Am. sual outcomes depend on prompt diag- tients with NF1 is typically diagnosed 2001;14(3):501-512. nosis and treatment of the glaucoma. early in childhood.3,7-8 In CEU associ- 5 Salim S, Shields MB. EyeNet Magazine. Effective surgical interventions ated with NF1, endothelialization of 2011;15(9):47-49. for CEU-associated glaucoma differ the iris surface may provide the forces 6 Salim S, Walton DS. Goniotomy and from the techniques used in primary needed to develop CEU and also cause Trabeculotomy. In: Yanoff M, Duker JS. congenital glaucoma. Although the iridocorneal adhesions that result in Ophthalmology. 3rd ed. New York: Else- success rate with early goniotomy in glaucoma. vier;2008:1241-1245. primary congenital glaucoma is greater The finding of EU on exam seems 7 Edward DP et al. Ophthalmology. 2012; than 80 percent, this procedure’s suc- to be closely correlated with an in- 119(7):1485-1194. cess appears to be much lower in eyes creased glaucoma risk in patients with 8 Morales J et al. Ophthalmology. 2009; with CEU, presumably due to severe NF1, specifically in those with orbital 116(9):1725-1730. angle dysgenesis in this disorder. Glau- involvement. Although glaucoma is coma filtration surgery or drainage considered a rare complication of NF1, Dr. Prenshaw is a recent graduate of the Uni- device placement may be necessary.4,6 it has been noted in 23 to 50 percent of versity of Tennessee at Memphis, where Dr. In one study, seven of nine patients patients with orbitofacial involvement Salim is associate professor of ophthalmology with glaucoma associated with CEU and an ipsilateral lid plexiform neuro- and director of the glaucoma service. The au- required trabeculectomy, and a total of fibroma.8 thors report no related financial interests. six goniotomies in three patients did Morales et al. found glaucoma in EXTRA not control intraocular pressure (IOP), 13 of 56 patients with NF1 with orbital MORE ONLINE. For more photos even with the adjunctive use of medi- involvement, and eight of these 13 were and a summary of Pearls, visit www.eyenet.org.

48 november 2013