Congenital Fibrovascular Pupillary Membranes: Clinical and Histopathologic Findings

Abstract

Purpose To report the clinical and histopathological findings associated with congenital fibrovascular pupillary membranes. Design Case series. Participants Seven infants; six with a unilateral congenital pupillary membrane and one with classic persistent fetal vasculature (PFV). Methods Patients underwent a membranectomy, pupilloplasty and/or a lensectomy. Histopathological examination was performed on the excised membranes. Main Outcome Measures Visual acuity and pupil size. Results Four of the 6 patients with a unilateral congenital pupillary membrane had one or more recurrences after a membranectomy and pupilloplasty. The most recent pupil size ranged from 2 to 5 mm in the affected eye. When last tested, the vision in the affected eye was excellent in 4 of the 6 patients. The two patients without recurrences of the pupillary membranes underwent multiple iris spincterotomies at the time of the initial surgery. Histopathological examination of two primary pupillary membranes showed fibrovascular tissue that did not stain for neuron specific enolase. Smooth muscle actin was only present in vascular walls. In contrast, histopathology of a recurrent pupillary membrane revealed collagenized fibrovascular tissue that was immunoreactive for smooth muscle actin. Finally, histopathology of the retrolenticular membrane excised from an infant with classic PFV was similar to the latter aside from hypercellularity. Conclusions Congenital fibrovascular pupillary membranes in infants are likely a variant of PFV that may recur if incompletely excised. The risk of these membranes recurring may be reduced by excising as much as the membrane as possible and enlarging the pupil with iris spincterotomies. A lensectomy should be avoided if possible.

Congenital cataract associated with persistent fetal vasculature: findings from IoLunder2

“…1 Congenital pupillary fibrovascular membranes, rather than being a separate entity, are histopathologically similar to the retrolenticular manifestations of PFV. 2 Cataract is a frequent secondary event in PFV due to invasion of the vascular remnants, lenticular swelling, intralenticular haemorrhage, or calcification. 1,3 PFV features have been found in a fifth of cases of unilateral congenital or infantile cataract, but are much less commonly noted in bilateral cataract.…”

Predictive value of pupillary response to mydriatic agents for diagnosis of retinopathy of prematurity

“…Congenital pupillary membranes may cause poor pupillary response independent of ROP, thus patients with this entity excluded from our study. [ 9 10 ]…”

Congenital fibrovascular pupillary membrane

“…Instillation of mydriatic agents, normally results in poor pupillary dilation, because of adherences between pupillary membrane and the iris, or posterior synechiae. ( 7 )…”

“…Congenital fibrovascular pupillary membrane is often characterized in its histology, ( 7 ) for presenting fibrovascular tissue, containing venules and arterioles, fibrocytes and extracellular collagen and immunoreactive elongated cells for smooth muscle.…”

“…A instilação de agentes midriáticos resulta, normalmente, em dilatação pupilar pobre, devido a aderências entre a membrana pupilar e a íris, ou por sinéquias posteriores. ( 7 )…”