Topographic changes in contralateral eye of a case of Terrien's marginal degeneration

A woman in her late twenties presented with blurring of vision in the right eye for 6 years. Retinoscopy showed a scissoring reflex in the right eye with best spectacle-corrected visual acuity of 20/40 in the right eye and 20/20 in the left eye. Slit-lamp examination of the right eye showed superior crescentic thinning with conjunctivalisation and lipid deposition while the left eye was normal. Corneal topography of the right eye showed inverse crab-claw pattern suggestive of Terrien's marginal degeneration (TMD) and the left eye showed inferior steepening with posterior elevation and thinning suggestive of keratoconus-like topography. This case shows that evaluation of the other apparently normal eye with 20/20 vision might show changes on topography in cases of unilateral TMD and needs follow-up to assess any further progression.