Pelvis and perineum
David Heylings, Stephen Carmichael, Samuel Leinster, Janak Saada, Bari M. Logan, Ralph T. Hutchings in McMinn’s Concise Human Anatomy, 2017
Ischioanal fossa - the fat-filled space (formerly called the ischiorectal fossa) below the pelvic diaphragm on either side of the anal canal (Figs. 7.3, 7.6-7.8), together forming the anal triangle of the perineum. In the lateral wall of the fossa, against the ischial tuberosity and obturator internus, is the pudendal (Alcock’s) canal, a fascial channel through which runs vessels and nerves that supply the perineum. Crossing the fossa from lateral to medial are the inferior rectal nerve and accompanying vessels passing to innervate the external anal sphincters. The fossa allows distension of the anal canal during defaecation. In the female the fossa also facilitates the great expansion of the vagina during childbirth.
Perianal and Anal Canal Neoplasms
Philip H. Gordon, Santhat Nivatvongs, Lee E. Smith, Scott Thorn Barrows, Carla Gunn, Gregory Blew, David Ehlert, Craig Kiefer, Kim Martens in Neoplasms of the Colon, Rectum, and Anus, 2007
The area above the dentate line up to the anorectal ring (the first 6–10 mm referred to as the transitional zone) has primarily cephalad lymphatic drainage via the superior rectal lymphatics to the inferior mesenteric nodes. It also has lesser drainage laterally along both the middle rectal vessels and inferior rectal vessels through the ischioanal fossa to the internal iliac nodes. Lymphatic drainage from the anal canal below the dentate line drains to the inguinal nodes. However, secondary drainage can follow the inferior rectal lymphatics to the ischioanal nodes and internal iliac nodes, and along the superior rectal nodes (see Fig. 20B in Chapter 1). Lymphatic drainage of the perianal skin is entirely to the inguinal nodes.
Anorectal Abscess and Fistula
Peter Sagar, Andrew G. Hill, Charles H. Knowles, Stefan Post, Willem A. Bemelman, Patricia L. Roberts, Susan Galandiuk, John R.T. Monson, Michael R.B. Keighley, Norman S. Williams in Keighley & Williams’ Surgery of the Anus, Rectum and Colon, 2019
Ischioanal abscess: Lateral extension along the fibroelastic septa passing through the external anal sphincter results in an ischioanal abscess. The ischioanal fossa (formerly called ischiorectal fossa) is the fat-filled space located lateral to the anal canal and inferior to the pelvic diaphragm. It is somewhat prismatic in shape, with its base directed to the surface of the perineum. High ischioanal abscesses, located just below the pelvic floor, are often difficult to diagnose by inspection and physical examination alone, as they present with constitutional symptoms and only a vague fullness in the buttock(s). Spread to the opposite side (horseshoe) is not uncommon in advanced sepsis.
Is extralevator abdominoperineal resection necessary for low rectal carcinoma in the neoadjuvant chemoradiotherapy era?
Published in Acta Chirurgica Belgica, 2020
Hikmet Erhan Güven, Bülent Aksel
Laparoscopic mesorectal mobilization was achieved dissecting the surgical field bordered by the upper edge of the coccyx, autonomous nerves, and inferior border of seminal vesicles or cervix of the uterus. Patients were given a modified lithotomy position for APR and a conventional APR was performed without removing the coccyx. During ELAPR, patients were given a prone jackknife position. The perineal incision was extended towards the lateral portion of the external anal sphincter. Dissection was extended through the ischioanal fossa until the insertion of the levator muscle is reached. Levator muscles were divided from their origin above the arcuate line and included in the specimen. Coccyx was routinely resected during ELAPR.
Related Knowledge Centers
- Internal Pudendal Artery
- Pudendal Nerve
- Pelvic Floor
- Perineum
- Obturator Canal
- Anal Fascia
- Pudendal Canal
- Internal Pudendal Veins
- Inferior Rectal Artery
- Inferior Rectal Veins