Extensive Persistent Pupillary Membranes: Conservative Management

Extensive Persistent Pupillary Membranes: Conservative Management

Extensive Persistent Pupillary Membranes: Conservative Management Neepa M. Thacker, MD,a Michelle T. Brit, MD,a and Joseph L. Demer, MD, PhDa,b Extens...

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Extensive Persistent Pupillary Membranes: Conservative Management Neepa M. Thacker, MD,a Michelle T. Brit, MD,a and Joseph L. Demer, MD, PhDa,b Extensive persistent pupillary membranes (PPMs) may appear to occlude the pupil so completely as to preclude useful vision. They often motivate aggressive interventions. We present a 6-year-old girl with bilateral extensive densely pigmented pupillary membranes in whom good vision was obtained without pharmacologic, laser, or surgical intervention. There was associated ametropic amblyopia and exotropia in the patient, which were effectively treated with spectacles and occlusion therapy, with the patient responding conventionally. In view of our findings, we recommend a trial of conservative management before surgical intervention even in cases of dense PPMs. Persistent pupillary membrane (PPM) is a common congenital abnormality of the iris, found as at least a remnant in 30% to 95% of healthy normally sighted adults.1 Although diaphanous PPMs typically regress in the first year of life, remnants often persist in adults. These PPMs range from fine strands to dense pigmented membranes that completely span the pupil, altering the red reflex and impairing vision.1-3 However, extensive bilateral PPMs are rare. The management of extensive PPMs is controversial, as it may be medical, surgical, or laser, as well as appropriate timing of the intervention. We report a case of bilateral extensive pupillary membranes achieving a visual acuity of 20/40 OD and 20/50 OS with conservative management only.

CASE REPORT An otherwise-healthy 6-year-old girl was found to have decreased vision on her first school screening examination. The child’s mother had noticed that the child’s pupils looked unusual since birth and that her eyes occasionally turned out. Past medical and family histories were non-

From the aDepartment of Ophthalmology, Jules Stein Eye Institute, University of California, Los Angeles, and bDepartment of Neurology, University of California, Los Angeles, California. Supported by grants from the National Eye Institute: consortium grant EY-08313; core grant EY- 00331 to the Department of Ophthalmology at the University of California Los Angeles. Also supported by an unrestricted grant from Research to Prevent Blindness. Joseph L. Demer is Grace and Walter Lantz Professor of Ophthalmology. Submitted October 7, 2002. Revision accepted May 6, 2005. Reprint requests: Joseph L. Demer, MD, PhD, Jules Stein Eye Institute, 100 Stein Plaza UCLA, Los Angeles, CA 90095-7002 (e-mail: [email protected]). J AAPOS 2005;9:495-496. Copyright © 2005 by the American Association for Pediatric Ophthalmology and Strabismus. 1091-8531/2005/$35.00 ⫹ 0 doi:10.1016/j.jaapos.2005.05.008

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contributory. Unaided vision was 20/100 OD and 20/200 OS. Vision with pinhole improved to 20/70 OD and 20/ 100 OS. Testing of alignment revealed a 45-prism diopter (PD) of poorly controlled intermittent exotropia at distance. Ocular versions were full. Slit-lamp biomicroscopy showed thick, dark-brown PPMs occluding both pupils with scattered fenestrations producing polycoria (Figures 1 and 2). The right eye was more severely affected than the left eye. No red reflex was visible without dilation. On dilation, there was a good red reflex and, despite a difficult view, normal retina and optic discs were observed in both eyes. Cycloplegic radioscopy revealed a refractive error of ⫹ 5.75 ⫹ 3.00 axis 100° OD and ⫹ 6.50 ⫹ 4.25 axis 90° OS. Full spectacle correction of these ametropias was prescribed. After 6 months of spectacles and part-time occlusion of the OD, visual acuity improved to 20/40 OD and 20/50 OS. The intermittent exotropia angle was reduced to 25 PD. With reduction of plus spectacle power, the intermittent exodeviation was converted to a wellcontrolled exophoria of 14 prism diopters. Best-corrected visual acuity remains 20/40 OD and 20/50 OS both in light and dark, with and without dilation. Stereopsis was 200 seconds/arc by the Titmus test.

DISCUSSION During embryogenesis the iris vasculature and the pupillary membrane derive from the anterior tunica vasculosa lentis, which normally atrophies in the third trimester to form the pupillary aperture. Incomplete degeneration leaves a PPM attached to the iris collarette and occasionally adhering to the surface of the lens or associated with cataract or other ocular anomalies.2,4 PPMs usually regress; however, if the membrane is extensive and persists after a year of age, it may not regress. Although this case of PPM is sporadic, there are reported cases of autosomaldominant inheritance.5 The histopathology of surgically removed membranes has revealed spindle shaped cells with pigment and blood vessels. Thickening of the iris stroma with increased number of fibrocytes and collagen has been reported.3,6 An extensive PPM such as this one creates, for the physician, fear of occlusion amblyopia, leading many authors to advocate prompt surgical intervention.3,5,6 Different modes of treatment have been suggested depending on the PPM extent. Miller et al4 have studied the effect of the pupil size on visual acuity. They report that a pupillary size of at least 1.5 mm is required for optimal acuity. They advocated the use of mydriatics to increase pupil size to 1.5 October 2005

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FIG 1. Slit-lamp photograph of the pupillary membrane OD.

Journal of AAPOS Volume 9 Number 5 October 2005

Good vision has been reported without intervention in 2 previous cases in which the PPMs were incidental findings in asymptomatic patients without associated ocular abnormalities.2,10 The current case was complicated by significant ametropia and strabismus. We attributed the reduced visual acuity to anisometropic amblyopia because the visual acuity did not immediately improve on dilation. Later improvement in vision during spectacle correction of ametropia is evidence in favor of anisometropic rather than occlusion amblyiopia. Refractive therapy controlled the intermittent exotropia. Despite the dense PPMs, the present case responded to conventional treatment of ametropia, amblyopia, and strabismus. On the basis of our experience in this extreme case and the absence of conclusive evidence of dense amblyopia secondary to PPMs alone in adults, we suggest that management could be conservative even in cases of dense bilateral PPMs. Factors favoring conservative management could include visualization of the red reflex and fundus with dilation. A trial of refractive correction and amblyopia therapy is recommended before deciding on surgery for this condition. This recommendation is not applicable if there is no red reflex with dilation, because in that case retinoscopy cannot be performed to determine refractive error, and occlusion amblyopia will likely result. Unilateral PPMs might be more likely than bilateral ones to produce amblyopia, but a trial of conservative therapy may nevertheless be appropriate before surgical intervention. References

FIG 2. Slit-lamp photograph of the pupillary membrane OS.

mm or larger in these cases.4 Different reported surgical treatments include iridectomy and pupilloplasty and were mostly performed in very young children. Complications included infection, bleeding, cataracts, and adverse reactions to anesthesia.1,5 Other authors report successful treatment with Nd: YAG laser membraneotomy.7-9 These patients were older, ie, teenagers to adults, and were treated for either cosmetic reasons or to improve visual function in bright light. They all achieved 20/20-20/40 vision but even the authors themselves could not explain why these patients did not have amblyopia despite ominous appearing PPMs.7-9 Risks of laser treatment include hyphema, cataracts, glaucoma, and requirement of general anesthesia in infants.

1. Jacobs M, Jaouni Z, Crompton J, Kriss A, Taylor D. Persistent papillary membranes. J Pediatr Ophthalmol Strabismus 1991;28: 215-8. 2. Mader T, Wergeland F, Chismire K, Stephan M. Enlarged pupillary membranes. J Pediatr Ophthalmol Strabismus 1988;25:73-5. 3. Reynolds J, Hiles D, Johnson B, Biglan A. Hyperplastic persistent papillary membrane—surgical management. J Pediatr Ophthalmol Strabismus 1983;20:149-52. 4. Miller S, Judisch F. Persistent papillary membrane successful medical management. Arch Ophthalmol 1979;97:1911-3. 5. Merin S, Crawford J, Cardarelli J. Hyperplastic persistent papillary membrane. Am J Ophthalmol 1971;72:717-9. 6. Burton B, Adams G. Persistent pupillary membrane. Br J Ophthalmol 1998;82:711-2. 7. Ramakrishnan R, Natchiar G, Michon J, Robin A. Bilateral extensive persistent pupillary membranes treated with the neodymium-YAG laser. Arch Ophthalmol 1993;111:28. 8. Kumar H, Sakhuja N, Sachdev M. Hyperplastic persistent pupillary membrane and laser therapy. Ophthalmic Surg 1994;25:189-90. 9. Vega L, Sabates R. Neodymium: YAG laser treatment of persistent pupilllary membrane. Ophthalmic Surg 1987;18:452-3. 10. Kolin T, Murphee A. Hyperplastic persistent papillary membrane. Am J Ophthalmol 1997;123:839-41.