small sebaceous gland abnormal perianal sebaceous gland morphology small perianal sebaceous gland MP:0013382 MPheno.ontology decreased anal gland size decreased circumanal gland size decreased perianal gland size decreased perianal sebaceous gland size decreased size of the modified holocrine gland that is part of the pilosebaceous unit of a hair located in the area around the anus; each of the specialized large hair follicles that surround and form a network around the anus has a pair of large sebaceous glands that empty into the follicle; perianal glands may function as scent glands reduced anal gland size reduced circumanal gland size reduced perianal gland size reduced perianal sebaceous gland size small anal gland small circumanal gland small perianal gland