4. Clinical features
• Benign:- unilateral, relative slow progress,in elderly white race
• Virulent type:- progressive, bilateral,,in young African, high risk of scleral
involvement
1. Symptoms:- severe pain, photophobia,lacrimation, defective vision
2. Signs:-
• Superficial ulcer :- start at corneal margin , patches of grey infiltrate to
shallow furrow over the whole cornea
• Peripheral ulcer:- forms whitish overhanging edge vascularized base,
• In end stage cornea become thin and conjuctivised
• Ulcer rarely perforates and sclera remain involved
