Placido disc is used for: (A) Uveitis, (B) Keratoconus, (C) Retinoblastoma, (D) Retinal detachment
Answer is B. It is a disc painted with alternating black and white circles. Used to assess the smoothness and curvature of corneal surface. It shows irregularity of circles in keratoconus. Ref khurana page no.126