What is an indolent ulcer in a dog? Indolent ulcers are typically non-healing superficial corneal ulcers of dogs otherwise known as superficial chronic corneal epithelial defects (SCCEDs). These are also known as canine recurrent erosions, Boxer ulcers, nonhealing erosions, and recurrent epithelial erosions, amongst others. These ulcers are commonly seen in the Boxer breed. These ulcers are slow to heal (weeks to months) and are painful.