Corneal ulcers in cats
Corneal ulcers in cats can be caused by trauma, detergent burns, infections, and other eye diseases. One common cause not seen in dogs is infection with feline herpesvirus 1 (FHV-1). FHV-1 causes ulceration by direct infection of the epithelial cells. Lesions appear as round or dendritic (branching) ulcers. FHV-1 also suppresses healing of the cornea. Symptoms include conjunctivitis, squinting, eye discharge, and blood vessels on the cornea. It can cause severe scarring. Treatment is with topical antiviral drugs and antibiotics, and oral L-lysine, which competes with arginine and inhibits viral replication. Corneal ulcers in horses
Corneal ulceration is a very common disease of the equine eye and can have sight-threatening consequences. Aggressive treatment is always indicated, as even apparently mild ulcers can progress quickly, causing serious complications. Causes
A distinct cause for initial ulceration is not commonly found, although in many cases it can be assumed to be traumatic in origin. The horses eye is especially vulnerable to trauma due to its prominent position, compared with other species. Exposure keratitis (inflamed cornea) can occur in the horse, most commonly secondary to facial nerve paralysis. Hospitalised animals have been shown to have a decreased corneal reflex, and this corresponds to an increased incidence of ulcers in the hospitalised population. Foreign bodies embedded in the palpebral conjunctiva or the nictitating membrane can cause persistent irritation and ulceration. Often the shape and distribution of the lesion is suggestive of this aetiology, but even in the absence of a characteristic lesion their presence should be considered and sought out.
A cat named Frankenlouie was a famous example noted by the Guinness Book of World Records in 2012 for being the longest surviving Janus cat. Treatment
Few individuals survive until birth. For those who do, the only treatment available is to surgically remove the parasitic twin. Of the two documented attempts, however, one child died within hours and neither reached their second birthday. The problem with surgical intervention is that the arterial supplies of the head are so intertwined that it is very hard to control the bleeding, but it has been suggested that cutting off the parasitic twins arterial supply might improve the odds of the developed twins survival. Prevalence
Only ten cases of craniopagus parasiticus have been documented, out of a total of at least eighty known cases of craniopagus in general.Only four cases have been documented by modern medicine to have survived birth:

An earlier case was the so-called "Two-Headed Boy of Bengal", who was born in 1783 and died of a cobra bite in 1787. His skull remains in the collection of the Hunterian Museum of the Royal College of Surgeons of London. On December 10, 2003, Rebeca Martínez was born in the Dominican Republic with this rare condition. She was the first baby born with the condition to undergo an operation to remove the second head. She died on February 7, 2004, after an 11-hour operation. On March 30, 2004, Manar Maged was born with the rare condition. On February 19, 2005, 10-month-old Manar underwent a successful 13-hour surgery in Egypt.