• To discuss the normal anatomy of the ischiorectal fossa (IRF) by computed tomography (CT) and magnetic resonance (MR). • To illustrate the most common pathologic entities that affect the ischiorectal fossa and to describe the CT and MR imaging findings of the pathology affecting the ischiorectal fossa. • To review the literature about the ischiorectal fossa.

A wide spectrum of disease processes involves the ischiorectal fossa, including congenital and developmental lesions; inflammatory and traumatic conditions; primary tumors; and other processes. We reviewed all of abdominal CT and MR reports in the last three years in our institutions. We selected the cases with ischiorectal fossa pathology and they were reviewed by two radiologists who were unaware of CT and MR findings. Since July 2002 from to July 2005 we encountered twenty five cases involving the ischiorectal fossa. Classification • Congenital and development...

NORMAL ANATOMY The anatomy of the ischiorectal fossa (Fig 1) and their relationship to other pelvic organs are well demonstrated with high-resolution computed tomography (Fig 2) scans as well as by magnetic resonance imaging (Fig 3). Several anatomic spaces can be distinguished in and about the anorectal region in the perineum, including the perianal, ischiorectal fossa (Fig 4) or ischional, intersphincteric, and supralevator spaces (Fig 5). The ischiorectal fossa is the largest of these anorectal spaces filled with fat. Both spaces communicate posteriorly through the...

• Familiarity with the imaging features and differential diagnoses of various ischiorectal pathological processes will facilitate prompt accurate diagnosis and treatment. • The anatomy of the ischiorectal fossa and its relationship to other pelvic organs is well demonstrated with high-resolution computed tomography scans as well as by magnetic resonance imaging. • Both CT and MR imaging are useful in the definitive diagnosis of these pathological conditions, with MR imaging being the modality of choice because of its superior contrast resolution and multiplanar capability. • MR...

Presenting author's Juan Carlos Quintero Rivera Hospital Germans Trias i Pujol Carretera de Canyet, s/n 08916 Badalona Spain E-mail adress of the first autor: [email protected] [email protected]