Keratoglobus and posterior subcapsular cataract: surgical considerations and in vivo microstructural analysis

We report sporadic, bilateral keratoglobus associated with posterior subcapsular cataract in a 43-year-old man. Slitlamp biomicroscopy showed symmetric arcus senilis-like deposits, a polygonal appearance resembling crocodile shagreen, an unusual endothelial appearance, and posterior subcapsular cataract. Orbscan II pachymetry maps (Bausch & Lomb) demonstrated bilateral diffuse corneal thinning (359.53 microm +/- 21.15 [SD] in the right eye and 379.61 +/- 11.49 microm in the left eye). These thickness values were confirmed by ultrasound pachymetry. In vivo confocal microscopy showed multiple criss-crossing dark lines and no identifiable cellular elements within the stroma. There were mild to moderate, guttata-like endothelial changes surrounded by pleomorphic cells. Phacoemulsification was performed in the left eye after careful consideration of the presenting features and modification of the surgical technique. Minimal structural alteration was observed during microstructural analysis 7 months after surgery. The endothelial morphology postoperatively was similar to that at baseline.