title: Large epidermal cyst involving the ischiorectal fossa: MR demonstration.
abstract: A large subcutaneous mass was noted in the buttock of a 79-year-old man. Computed tomography (CT) and magnetic resonance imaging (MRI) showed a thin-walled cystic mass that involved the ischiorectal fossa. The content appeared hyperintense on T1-weighted images. T2-weighted images demonstrated a considerable amount of debris. At surgery an epidermal cyst with markedly keratinized squamous epithelium was found. It contained much keratin and cholesterin.
authors.affiliation: Department of Radiology, Numazu City Hospital, Japan.
authors.forename: H
authors.initials: H
authors.lastname: Fujimoto
authors.forename: K
authors.initials: K
authors.lastname: Murakami
authors.forename: A
authors.initials: A
authors.lastname: Kashimada
authors.forename: M
authors.initials: M
authors.lastname: Terauchi
authors.forename: K
authors.initials: K
authors.lastname: Ozawa
authors.forename: K
authors.initials: K
authors.lastname: Nosaka
authors.forename: N
authors.initials: N
authors.lastname: Arimizu
mesh_terms: D000368:Aged; D002081:Buttocks; D004814:Epidermal Cyst / Q000175:diagnosis* / Q000473:pathology / Q000601:surgery; D006801:Humans; D007512:Ischium; D008279:Magnetic Resonance Imaging; D008297:Male; D012002:Rectal Diseases / Q000175:diagnosis / Q000473:pathology / Q000601:surgery; D014057:Tomography, X-Ray Computed