Clinical application of an ultrasonically activated scalpel in neurosurgery

Ultrasonically activated scalpel (UAS) is a surgical device utilizing ultra sonic energy to cut and coagulate tissues simultaneously. The actions and f eatures of UAS are considerably different from those of conventional ultras onic cavitational aspirators (UCA) that have been used frequently in the ne urosurgical field The UAS has been used routinely in a number of general su rgeries, including laparoscopic surgeries and open surgeries of the lung an d liver. However, neurosurgical application of UAS has not been reported. W e used UAS in surgical resection of intracranial tumors consisting of five meningiomas, two gliomas, and one metastatic brain tumor, and monitored the rmal changes in tissues using thermoencephaloscopy to possibility of heat i njury by UAS. It was used to achieve both dissection of the attachment of i nvestigate the possibilities meningiomas and internal decompression of the tumors and allowed efficient resection of various tumors with minimal bleed ing by adjustment of the combination of coagulation and cutting powers at f ive different positions. The attachment of meningiomas was coagulated and c ut easily and safely by UAS. Moreover, infrared thermographic study showed that the degree of temperature increase and the area of elevated temperatur e were extremely limited in UAS. The current study suggests that it is a pr omising device in neurosurgery.