ECTASIA CORNEÆ. KERATOCONUS. CONICAL CORNEA.

This consists in a thinning and protrusion of the cornea in the form of a blunt cone, without loss of transparency. It has accordingly been called staphyloma pellucida. There is a gradual attenuation and distension of the corneal tissue from some unknown cause. It has been seen mainly in the young and is manifestly due to a trophic defect. Stockfleth records a case in a foal and Bayer in a cow. No satisfactory treatment has been proposed, but as the trouble usually comes to a standstill without perforation, it can be left to take its course. With rapid increase and manifest tension antiseptic puncture of the cornea or even iridectomy might be tried.