Conservative management of bilateral persistent pupillary membranes with 18 years of follow-up

Abstract

Dear Editor, Remnants of pupillary membranes are a common clinical finding in about 95% of healthy neonates [1] and 20% of adults. They represent an incomplete involution of the tunica vasculosa lentis, and do not affect the vision in the vast majoritiy of cases. However, bilateral dense persistent pupillary membranes (PPM) are a rare congenital abnormality. They can be associated with other ocular pathologies [2]. If they seem to be dense and to cover the visual axis, the management of these patients remains controversial, and a case-dependent decision of balancing the risks of surgery against amblyopia needs to be made. A 6-month-old female was referred by her pediatrician because of uncommon-looking pupils. She was an otherwise healthy infant, born full-term without a history of pregnancy complication or a family history of ocular disease. On ocular examination under general anesthesia, we found dense PPM covering the visual axis of both eyes (Fig. 1a–d). Anterior segments, including chamber angles, were otherwise unremarkable, and fundus examination did not reveal any pathological findings. The intraocular pressure was not elevated. As fixation was normal for her age group and no squinting detectable, an observant management was adopted. The patient was seen regularly within the following years. She did not develop strabism. Retinoscopy led to a prescription of spectacles with a refraction of +9.0−2.0 axis 15° OD and +9.0−2.0 axis 175° OS at the age of 4.5 years. With this correction, the visual acuity was 20/32 on both eyes. About a year later, amblyopia therapy was performed with optical penalization of her right eye for 6 months, leading to a VA of 20/40 on both eyes. Up to today, her vision has continually improved to 20/20 in both eyes with small variations, and a stable refraction of +8.25−3.5 axis 2° OD and +8.25−3.25 axis 174° OS, respectively (Fig. 2). The PPMs remain unchanged. PPMs are a rare finding. The probability of regression may depend on the composition of membranes. Histopathology of excised membranes has revealed large amounts of collagen bundles with fibroblasts and some macrophages [4]. Steuhl et al. speculate that an increased amount of collagen and blood vessels within the membranes could inhibit regression. Although description of autosomal dominant inheritance does exist [3], sporadic cases of PPM seem to prevail [4]. Conventional surgical treatments [4, 5] and laser treatments with a Neodym–YAG laser [6, 7] have been described as leading to good visual results. Nevertheless, potential complications including infection, bleeding and mainly induction of cataract play an important role when planning treatment for an individual patient. The case described herein, and others, demonstrate that even dense PPM can lead to satisfying visual results with a Authors agree to allow Graefes Archive for Clinical and Experimental Ophthalmology to review their data upon request. Authors have no financial interests to disclose. B. Meyer-Rusenberg (*) :M. Thill Department of Ophthalmology, University Medical Center Hamburg–Eppendorf, Martinistrasse 52, 20246 Hamburg, Germany e-mail: b.meyer-ruesenberg@uke.de