Amsler sign is seen in

HETEROCHROMIC IRIDOCYCLITIS OF FUCHS It is a low grade chronic cyclitis, the only apparent features of which are a lightening of the colour of the affected iris and presence of few keratic precipitates on cornea. Iris become atrophic, loses its markings and readily transilluminates in circumscribed areas, and a cataract develops. Loss of sympathetic nerve supply leading to dilatation of blood vessels, white cells escape and get deposited on the cornea as precipitates. The cataract has good operative prognosis, but secondary glaucoma develops. During cataract surgery, fine filiform hemorrhage from the opposite angle has been noted to occur as soon as the anterior chamber is opened- reffered to as AMSLER SIGN. Ref:- Parsons diseases of eye; pg num:-251