Unusual sequelae of staphyloma following Ahmed glaucoma valve explantation and its management

We report a case of a 7-year-old boy, who presented with plate exposure after Ahmed glaucoma valve (AGV) implantation in the eye with secondary glaucoma following penetrating trauma. He underwent AGV explantation with scleral patch graft and conjunctival limbal autograft and started on topical and oral antiglaucoma medication (AGM) for intraocular pressure (IOP) control. Two months later, he presented to us with high intraocular pressure and uveal tissue prolapse at the site of previous tube entry displacing the scleral and conjunctival grafts posteriorly. The defect was closed with corneal patch graft. Patient underwent limited transscleral cyclophotocoagulation and was maintained on topical AGM for IOP control. Our case highlights that explantation is a definitive management in such cases of plate exposure. Tube entry site is a potential weak area and there is risk of uveal prolapse through this area with high IOP. Corneal patch graft helps in successfully managing such defects involving the sclero-limbal region.

Ultrastructure of Trout Cornea

The ultrastructure of the brook, brown, and rainbow trout cornea as observed using the light and electron microscopes is described. The transition between the central and limbal areas of the cornea is included. The limbal region, unlike the central cornea, contained epithelial microvilli, unorganized Bowman's membrane with various size collagen fibrils, and a stroma containing melanocytes and capillaries. These corneas also possess prominent keratocytes and an endothelium.