Description: The pelvic lymph vessels and nodes accompany the blood vessels.  The small, thin, lymph vessels are not usually visible to the naked eye. The round or bean-shaped nodes, usually 0.5-1.5cm in length, are clustered in regions along the aorta, the iliac, the obturator, and the femoral vessels, and in the inguinal canal. In general, the pelvic organs drain through the external and the internal iliac lymph nodes, and the sacral nodes. The external nodes lie on the corresponding iliac vessels, and drain the lower limbs, bladder, vagina, cervix, uterus, and anterior abd. wall . The internal iliac nodes drain all of the pelvic viscera, deep parts of the perineum, and the gluteal and thigh regions. The sacral nodes receive lymph from the posterior pelvic wall, the rectum, the cervix, and the bladder neck. Over the common iliac v., two groups can be identified: a lateral group lying along the vessels, and a medial group lying in the angle between the joining vessels. A couple of nodes can usually be identified between the leaves of the broad ligament adjacent to the cervix (cervical nodes).