[Use of real-time ultrasonography in neurosurgical operations]

The authors' experience with the application of real-time ultrasonography during 29 and after 3 neurosurgical operations is reported. Intraoperative sonography was performed in 29 cases. The neurosurgical operations include aneurysm surgery in 13 cases, removal of intracerebral hematoma in 11 cases, neoplasm surgery in 2 cases, and so on. Moreover, sonographic examination through bone defect was performed in 3 cases after decompression craniectomy. The instrument used was an ATL (Advanced Technology Laboratories, Bellevue, WA, USA) mechanical sector scanner of which scanhead contained transducers of three frequencies: 3, 5 and 7.5 MHz. The scanhead was wrapped with a sterile rubber bag after acoustic coupling gel had been applied to the head's tip. Then the scanhead was placed on the dura and ultrasonic examination was performed. The result was that the lesion was clearly identified and localized in all cases except for three cases of mild subarachnoid hemorrhage. In addition, in the two cases of needle aspiration of cyst or hematoma, the needle was easily identified and needle aspiration was performed safely and accurately. Moreover, during aneurysm surgery, aneurysm itself was detected in two cases by the real-time ultrasonic imaging. Especially, in the case with large aneurysm of the left middle cerebral artery, the findings about the aneurysmal wall, that is to say, which part is thick and which part is thin, could be obtained. Prior to the operation of aneurysm, cerebral angiogram and computerized tomographic scan are always examined thoroughly, but information about aneurysmal wall can be rarely obtained by them.(ABSTRACT TRUNCATED AT 250 WORDS)