Ultrasound-guided brain biopsy: a personal experience with emphasis on its indication.

Between January 1989 and June 1991, 40 ultrasound-guided biopsies of supratentorial brain lesions exceeding 15 mm in diameter were performed. The apparatus used was Berger's neurobiopsy set, intraoperative 5 = MHz transducer, and a B-mode scanner. In 38 cases (95%) the procedure provided a histological diagnosis at the first attempt; in two patients, early in the present series, biopsy was repeated by computed tomography-guided technique due to insufficient samples. Operative mortality was zero and there were no septic complications. Clinical symptoms were stationary after the procedure in 34 cases; two cases temporarily worsened due to postbiopsy edema and subcortical hemorrhage, respectively; and four other cases showed an improvement as a result of evacuation of neoplastic cysts. Histologically, there were 24 primary malignant tumors, eight low-grade glial tumors, five metastatic tumors, two abscesses, and one lymphoma. The ultrasound method for brain lesion biopsy was found to be a simple, quick, and low-cost method that gave reliable results. It is indicated for supratentorial lesions over 15 mm in diameter that do not demand absolute anatomical accuracy.