Bubbles in the bleb--troubles in the bleb? Molteno implant and intraocular tamponade with silicone oil in an aphakic patient.

A 14-year-old aphakic girl who had had previous bilateral glaucoma surgery with a Molteno implant underwent pars plana vitrectomy and silicone-oil tamponade for proliferative-vitreoretinopathy retinal detachment in both eyes. The filtering bleb of the left eye was functional for 5 months before becoming available for histologic examination. We found numerous foreign-body granulomas coating the inner surface of the bleb, as well as intracellular and extracellular deposits of emulsified silicone oil in the wall of the bleb. In the fellow eye, the filtering bleb remained functional despite repeated vitreous surgery with silicone oil. Filtration in aphakic eyes with previous Molteno surgery and silicone-oil tamponade after vitrectomy may continue normally for a prolonged period of time, although emulsified oil droplets likely will have accumulated in the bleb and become incorporated in its fibrous capsule.