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.
A small number of chronic fissures heal without intervention but the vast majority do not. The treatment of chronic anal fissure is directed at reducing the spasm of the internal anal sphincter and hence, anal canal pressure. Traditionally this has been achieved surgically by sphincterotomy, where part of the internal anal sphincter is divided, but more recently various pharmacological agents have been shown to lower resting anal pressure and promote healing.