[Perianal fistula and anal fissure].

CRYPTOGLANDULAR ANAL FISTULA: Perianal abscesses are caused by cryptoglandular infections. Not every abscess will end in a fistula. The formation of a fistula is determined by the anatomy of the anal sphincter and perianal fistulas will not heal on their own. The therapy of a fistula is oriented between a more aggressive approach (operation) and a conservative treatment with fibrin glue or a plug. Definitive healing and the development of incontinence are the most important key points. ANAL FISSURES: Acute anal fissures should be treated conservatively by topical ointments, consisting of nitrates, calcium channel blockers and if all else fails by botulinum toxin. Treatment of chronic fissures will start conservatively but operative options are necessary in many cases. Operation of first choice is fissurectomy, including excision of fibrotic margins, curettage of the base and excision of the sentinel pile and anal polyps. Lateral internal sphincterotomy is associated with a certain degree of incontinence and needs critical long-term observation.