Scissor reflex is seen in -

Ans. is 'c' i.e., Keratoconus Kerotoconuso Keratoconus is a progressive, noninflammatory, bilateral ectatic corneal disease, characterized paraxial stromal thinning and weakening that leads to corneal surface distortion,o Essential pathological changes are thinning and ectasia which occur as a result of defective synthesis of mucopolysaccharide and collagen tissue,o It usually starts at puberty and progresses slowly.o Symptoms usually begins as blurred vision with shadowing around images.o Vision becomes progressively more blurred and distorted with associated glare, halos around lights, light sensitivity and ocular irritation.o Visual loss occurs primarily from irregular astigmatism and myopia, and secondarily from corneal scarring.o The hallmark of keratoconus is central or paracentral stromal thinning, apical protrusion of anterior corneaand irregular astigmatism.o The cornea thins near the centre and progressively bulges forwards, with the apex of cone always being slightly below the centre of the cornea,o Important findings an examination are -Distorted window reflex (Corneal reflex)Q.Fleisher's ringQ.Yawning reflex (Scissor reflex).Oil drop reflex.Munson's signso Treatment includesSpectacles for regular or mild irregular astigmatism.Rigid gas permeable contact lens for higher astigmatism.Epikeratoplasty in patients intolerant to lens and without significant corneal scarring.Keratoplasty penetrating or deep lamellar if there is significant corneal scarring.