Skin sloughing is the process of shedding dead surface cells from the skin. These free radicals damage the skin, leading to ulceration, necrosis, and sloughing. Facial pigmentation changes underneath the old skin which begins sloughing off like a mask. Putrefaction leads to the skin sloughing off around the worm. Ultimately, necrosis of the papillae results in sloughing into the lumen, causing hematuria. Preservative-free eye ointment is preferred, as preservative can cause corneal epithelial sloughing and conjunctival hyperemia. This is made possible because of the virus sloughing off into the mucus. The shedding of scales is called "ecdysis", or, in normal usage "moulting" or "sloughing". The shedding of scales is called "ecdysis" (or in normal usage, "molting" or "sloughing"). Problems with this technique include loss of sensation, sexual function, and sloughing of the glans. Unabated soil sloughing can end in massive bank or slope failure. There is considerable sloughing of broken rock from these vertical surfaces of Goat Rock. Sloughing well is a key to winning at Sheepshead, especially as the picker. Not all sloughing serves an antifouling function.