The ultrasonic dissector facilitates laparoscopic cholecystectomy.

The ultrasonic dissector disrupts tissues in proportion to their fluid content by ultrasonically induced cavitational forces. Since sturdy tissues are spared, the instrument tends to follow tissue planes and to dissect fat and other soft tissues selectively. We performed a prospective, randomized, controlled trial in 73 patients comparing the safety and efficacy of a prototype ultrasonic dissector with that of electrosurgery and laser during laparoscopic cholecystectomy. Randomization was as follows: ultrasonic dissector, 37 patients; electrosurgery, 21 patients; and laser, 15 patients. The results were not different with respect to patient characteristics, amount of blood loss, technical difficulties, length of hospital stay, or return to work. Subjectively, the ultrasonic dissector was thought to be of special value in isolating the hilar structures, particularly when they were edematous or embedded in fat. The ultrasonic dissector disintegrated the fat, which was rapidly cleared up the suction channel, allowing the cystic duct and artery to be bared with less risk of injury. We concluded that the ultrasonic dissector has unique attributes that contribute to the ease and safety of laparoscopic cholecystectomy.