[Ultrasound tomography in postoperative monitoring of infratentorial space-occupying lesions].

After osteoclastic trepanations of the posterior fossa for cystic or solid processes of the cerebellum and the cerebellopontine angle, ultrasonic tomography is a suitable imaging procedure. A mechanical sector probe with a frequency of 3.5 MHz is recommended as transducer. The postoperative ultrasonic findings are the basis for the sonographic observation of the further evolution. Cystic and solid processes can be localized and their dimensions metrically determined by means of multiple plane cross-sectional imaging. Ultrasonic tomography is recommended as a primary diagnostic method owing to its lack of invasivity and radiation exposure, simple handling and repeatability. As a consequence, CT examinations can be better aimed.