Idiopathic subfoveal choroidal neovascular membrane in a 21-month-old child: Ultrastructural features and implication for membranogenesis

PurposeTo report the clinical and pathologic features of an idiopathic choroidal neovascular membrane (CNVM) in a 21-month-old child and to discuss the unique findings of infantile CNVM in the context of understanding the mechanism of membrane formation.MethodsThe CNVM was removed by submacular surgery. Light and electron microscopic tissue analyses were used to elucidate the structure and constituents of the CNVM.ResultsPostoperative vision was 20/60 at 10 months without evidence of recurrence. Endothelium-lined vascular channels were observed within a membrane composed entirely of retinal pigment epithelial (RPE) cells with an associated fibrocollagenous and amorphous matrix. No inflammatory cells were identified. The RPE cells toward the inner (photoreceptor) side of the membrane exhibited a less-differentiated appearance, having lost their polarity and most of their cytoplasmic melanin granules. They secreted more prominent fibrils and mucopolysaccharides. Fenestrated endothelial cells surrounded by pericytes were present between the proliferating RPE cells.ConclusionsSubmacular surgery can be beneficial for idiopathic CNVM in pediatric patients, even at this early age. Proliferating RPE cells in the current membrane appear to be capable of performing all of the necessary functions associated with membranogenesis, even in the absence of inflammatory cells.