Marine stickleback populations live and breed strictly in the ocean. Sea-run stickleback fish are. anadromous, meaning that they are born in fresh water, spend most of their lives in the ocean, and. return to fresh water to breed. Freshwater stickleback fish live entirely in fresh water.
Among patients with Crohn's disease, 4% will have an anal fissure as the first manifestation of their Crohn's disease, and half of all patients with Crohn's disease eventually will develop an anal ulceration that may look like a fissure.
An anal fissure is a cut or a tear in the thin, delicate lining of your anus. The tear often exposes the muscle around the anus, called the anal sphincter. The damage can cause that muscle to spasm, which can pull apart the edges of the fissure even more. The spasms can cause pain and slow down the healing.