[Ultrasonic aspirator with controllable suction system--variable action suction adapter and clinical experience with it].

While the ultrasonic aspirator (UA) has been widely used as one of the indispensable tools in the field of neurosurgery, a potential risk when using the present UA is injury to the neurovascular structures due to ultrasonic pulverization and constant forceful suction power. We have devised a small variable action suction adapter that can be used in a similar manner to conventional surgical suction tubes. The UA control unit and the handpiece used in this study were the Sonopet UST-2000 and HA-01, respectively (M & M Corporation Tokyo, Japan). The handpiece is slim, with the mid-portion diameter of 13 mm, and it weighs 100 grams. A variable action suction adapter was made from polycarbonate of 15 x 12 x 13 mm in size. The adapter was connected to the suction tube using a Y-shaped connector (Fig. 2 A), which was integrated into the handpiece. The suction power is regulated by variably closing the oval-shaped hole. The adapter can be variously placed on and rotated around the handpiece (Fig. 2 B and C) so that either the right or left hand handles it in a similar fashion to conventional suction tubes. We used this UA in surgery for 8 patients with large brain tumors (meningioma in 5 cases, metastatic brain tumor in 2 cases and glioma in one case). It reduced the risk of suction-related injury to the neurovascular structures and was handled in a similar manner to conventional suction tubes. This adapter ensures the complete control of suction power, which will reduce the risk of suction injury.