Lateral to the anal canal is the ischioanal fossa that contains ischioanal fat. Before attempting to remove the fat, insert your index finger into the ischioanal fat pad lateral to the anal canal to identify the nerves and vessels traversing those spaces [lower finger inserted to the fossa, upper finger showing the extent of the superficial perineal pouch]. Locate the vessels and nerves in the ischioanal fossa and carefully remove the fat from it . Next, identify and clean the inferior rectal vessels and nerves.
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