Summary and ConclusionsHistologic examination was carried out on 32 surgical specimens removed by radical hemorrhoidectomy. Material for comparative study was also obtained from the adjacent rectal mucosa and from the subcutaneous portion of the external sphincter.Inflammatory exudates were minimal in those cases in which the overlying mucosa was intact, whether the hemorrhoids were thrombosed or not. It appeared that thrombosisper sedid not cause inflammatory changes in the hemorrhoidal area or in the surrounding tissues.When superficial ulceration was present there were marked inflammatory changes in the immediate vicinity but they disappeared rapidly in the deep tissues. Ulceration was found more frequently in cases of prolapsed and trombosed hemorrhoids.Even in the presence of ulceration there were no significant inflammatory changes in the deep tissues, the adjacent rectal mucosa or the subcutaneous portion of the external sphincter muscle.Ulceration of the overlying mucous membrane and not the presence of thrombosis seemed to be the determining factor in the degree of inflammatory change.The presence of recent thrombosis did not increase the difficulty of the operative procedure, the length of convalescence, the postoperative pain, the occurrence of postoperative infection, nor did it in any way impair the final result. We feel that early surgery in prolapsed and thrombosed hemorrhoids should be reserved for the experienced anorectal surgeon.