Structure and functional significance of the transverse vesical fold.

The plica vesicalis transversa or transverse vesical fold (TVF) is a peritoneal fold extending from the lateral side of the bladder to the side of the lesser pelvis near the deep inguinal ring. It is an important landmark in laparoscopic surgery of the pelvis but is variably observed in the embalmed cadaver. We investigated the gross anatomy of this structure in the cadaver and confirmed that its medial portion corresponds to the location of the superior vesical artery(ies), thus supporting the idea that the TVF is "mesovesical." However, no large vessels were observed grossly in the lateral portion of the TVF. The hypothesis that the lateral TVF has a suspensory function was tested histologically by comparison with the suspensory ligament of the duodenum and the phrenicocolic ligament, both of which have smooth muscle contributing to their inferred suspensory function. Microscopic examination of prepared samples from 20 cadavers shows that the TVF evinces no smooth muscle in either its lateral or medial segments. The TVF is demonstrated to be a mesentery-like reflection of peritoneum raised by branches of the superior vesical artery which provides no demonstrable structural support for the bladder. Implications of these findings include avoidance of sectioning of medial TVF during laparoscopic surgery because of its vascular nature, and inadvisability of utilizing any portion of theTVF for an anchor in reconstruction of the anterior pelvic floor within the paravesical fossae.

Variations of the arterial pattern in the upper limb revisited: a morphological and statistical study, with a review of the literature.

A total of 192 embalmed cadavers were examined in order to present a detailed study of arterial variations in the upper limb and a meta-analysis of them. The variable terminology previously used was unified into a homogenous and complete classification, with 12 categories covering all the previously reported variant patterns of the arm and forearm.

Median artery revisited.

This study confirms that the median artery may persist in adult life in 2 different patterns, palmar and antebrachial, based on their vascular territory. The palmar type, which represents the embryonic pattern, is large, long and reaches the palm. The antebrachial type,which represents a partial regression of the embryonic artery is slender, short, and terminates before reaching the wrist. These 2 arterial patterns appear with a different incidence. The palmar pattern was studied in the whole sample (120 cadavers) and had an incidence of 20%, being more frequent in females than in males (1.3:1), occurring unilaterally more often than bilaterally (4:1) and slightly more frequently on the right than on the left (1.1:1). The antebrachial pattern was studied in only 79 cadavers and had an incidence of 76%, being more frequent in females than in males (1.6:1); it was commoner unilaterally than bilaterally (1.5:1) and was again slightly more prevalent on the right than on the left (1.2:1). The origin of the median artery was variable in both patterns. The palmar type most frequently arose from the caudal angle between the ulnar artery and its common interosseous trunk (59%). The antebrachial pattern most frequently originated from the anterior interosseous artery (55%). Other origins, for both patterns, were from the ulnar artery or from the common interosseous trunk. The median artery in the antebrachial pattern terminated in the upper third (74%) or in the distal third of the forearm (26%). However, the palmar pattern ended as the 1st, 2nd or 1st and 2nd common digital arteries (65%) or joined the superficial palmar arch (35%). The median artery passed either anterior (67%) or posterior (25%) to the anterior interosseous nerve. It pierced the median nerve in the upper third of the forearm in 41% of cases with the palmar pattern and in none of the antebrachial cases. In 1 case the artery pierced both the anterior interosseous and median nerves.