vascular prominences formed by clusters of normally sacculated veins of the superior rectal venous plexus, fed by arteriovenous anastomoses that cause their engorgement; are usually found to lie laterally on the left and antero- and posterolaterally on the right side of the anal canal. SYN: cavernous bodies of anal canal, corpora cavernosa recti, hemorrhoidal cushions, threshold pads of anal canal.