Parietal group of the internal iliac nodes is the gluteal lymph node group. Gluteal lymph node group is localized at the fascial plane between gluteus maximus muscle and obturator internus muscle. Gluteal lymph nodes are subdivided into two groups: inferior gluteal lymph nodes located along the inferior gluteal vein (figure 1); superior gluteal lymph nodes located along the superior gluteal vein. Lymph from the deep tissues of the gluteal region drains into superior and inferior gluteal lymph nodes. Ischioanal lymph nodes are localized at the...

Images of patients who underwent pelvic MRI between October 2011 and July 2013 were retrospectively analysed. Presence of enlarged ischioanal fossa and inferior gluteal region lymph nodes were detected in 12 patients, 3 of whom were females. The age range was 35-68 years.

Enlarged lymph nodes were observed at the inferior gluteal region in 8 patients and at the ischioanal fossa in 4. Short axis lengths of the lymph nodes at inferior gluteal region were between 3 mm’s and 20 mm’s, the lymph nodes at ischioanal fossa were between 4 mm’s and 11’s mm. In patients with enlarged inferior gluteal lymph nodes the primary pathologies were prostate cancer that invades urethra and rectum (n=1) (figure 3), squamous cell cancer of anus (n=1),perianal fistula related to Crohn’s disease (n=1),...

Enlarged inferior gluteal and ischioanal lymph nodes can be seen at anal, distal rectal, perineal, gluteal, prostatic and urethral pathologies. High contrast resolution and image capabilities of MRI makes it an important assessment tool for evaluation of lymph nodes in these regions.

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