A 20 year old boy complaints of sudden pain in the left eye with loss of vision. On examination, was hazy and there was a bulging of left lower eyelid on looking down . Retinoscopy shows scissoring reflex; oil drop sign was positive. diagnosis?

These sign and symptoms are classic for keratoconus. Signs Direct ophthalmoscopy from a distance of half a metre shows a fairly well delineated 'oil droplet' reflex . Retinoscopy shows an irregular 'scissoring' reflex. Slit lamp biomicroscopy shows very fine, veical, deep stromal stress lines called as Vogt striae Epithelial iron deposits, best seen with a cobalt blue filter, may surround the base of the cone known as Fleischer ring Progressive corneal protrusion in a cone configuration with thinning maximal at the apex. Bulging of the lower lid in downgaze (Munson sign).