After the omentum has been lengthened to an appropriate extent to reach the head, several small (3- to 4-inch) transverse incisions are made on the chest wall slightly lateral to the midline, with the side of the midline to make the transverse incisions depending on which cerebral hemisphere the omentum is to be placed. These transverse incisions are connected subcutaneously, thus creating a tunnel that begins at the upper pole of the midline abdominal incision and travels subcutaneously, up the chest wall and neck to behind the ear.