Pellucid marginal degeneration coexistent with cornea plana in one member of a family exhibiting a novel KERA mutation

Characterised by flattening of the normally convex corneal surface, small corneas, high hyperopia, and arcus senilis, autosomal recessive cornea plana is secondary to KERA mutation.1–3 KERA encodes keratocan, an evolutionary conserved small leucine rich proteoglycan. Keratocan, highly and uniquely expressed in the cornea, is composed of core proteins consisting mostly of leucine rich repeats (LRRs).1–3 All patients documented to be homozygous for one of the four previously reported KERA mutations have disruption of LRR architecture and demonstrate similar cornea plana phenotypes.1–3 In contrast, corneal pellucid marginal degeneration (PMD) is an idiopathic progressive ectatic corneal disorder that is clinically diagnosed by characteristic thinning, resultant “against the rule” astigmatism, and absence of opacity.4 We report a case of superior …