Laparoscopic candidates with abdominal scars may have adhesions that result in visceral injury during trocar insertion. The purpose of this study was to evaluate the use of preoperative ultrasound mapping of abdominal wall adhesions, to provide safe initial laparoscopic access, and to guide the placement of subsequent trocars, facilitating adhesolysis when necessary. Thirty consecutive patients with previous abdominal surgery who were scheduled for laparoscopy underwent a preoperative ultrasonic examination of the abdominal wall using a 7-MHz linear ultrasound probe. Spontaneous viscera slide was measured during longitudinal scanning (normal = 2-5 cm) and induced viscera slide was evaluated during longitudinal and transverse scanning (normal = 1 cm or more) over the existing abdominal scar, the peri-umbilical region, and the remaining abdominal quadrants. Sixteen (53%) of 30 patients had adhesions under their scar and only four patients (25%) had umbilical adhesions. The 12 patients without umbilical adhesions all had successful closed cannulation while open cannulation at alternate sites was successful in the four individuals with umbilical adhesions. Blind umbilical needle cannulation was successfully done in all of the remaining 14 patients (47%) without visceral injury, including three patients (21%) with upper abdominal scars who were adhesion-free elsewhere. No adhesions were encountered that had not been preoperatively predicted by ultrasound. We conclude that examination of the abdominal wall with spontaneous and induced viscera slide, using ultrasound scanning, can reliably detect intraabdominal adhesions. The examination is best done on a highly selective basis by the operating surgeon to guide the location for initial trocar insertion

No abstract

The crystal structure of tetracyanoethylene oxide has been determined at room temperature from threedimensional X-ray and neutron diffraction data measured by counter methods. The comEound crystallizes in the space group C2,S-P2,jc with cell dimensions a = 9.718 (5), b = 6.141 (3), c = 12.162 ( 5 ) A and 6 = 110.28 (2)".The data were corrected for absorption and anisotropic extinction and refined by full-matrix least-squares techniques to weighted R factors of 0.033 for X-ray and 0.043 for neution data. The molecule packs in such a way that each cyano nitrogen closely approaches the triangle formed by the ring carbon and its two exocyclic carbon substituents. Similar packing in a number of closely related tetracyano compounds is discussed in relation to the observed nonlinearity of the C-C-N fragment. The data are shown to be consistent with an explanation for this bending based on delocalization of electron density into the antibonding T orbital of the cyano group. The thermal motion is analyzed in terms of a rigid body approximation.