Not a difficult question this if you’ve seen one of these before – a corneal sequestrum in a Persian cat. But what would you do with it?
These can be very difficult to deal with – remove them with a superficial keratectomy and they may extend throughout the cornea. Leave them be and they may eventually erode through the cornea and perforate the globe. A conjunctival flap after a keratectomy might work but the best treatment is a corneoconjunctival transposition graft as described by Stacey Andrew in her excellent 2001 paper ‘Corneoconjunctival transposition for the treatment of feline corneal sequestra’ in Veterinary Ophthalmology 4:107-11. The only trouble with this particular case was that the black deposit was actually in the epithelium of a graft I had placed after removing a deep sequestrum in this little cat, under a year old. Thankfully the new sequestrum lifted off with just topical anaesthetic leaving this cornea underneath. I just have to cross my fingers that the same thing doesn’t happen again! Is that all I can do?