[Intraoperative use of sonography in cerebral lesions].

The advantages of intraoperative ultrasound are the localisation and biopsy of low grade subcortical gliomas of small deep seated lesions, e.g. metastasis, puncture of brain abscess and cysts. Also the endoscopic approach for intracranial haemorrhage, the placement of catheters in narrow ventricles, the detection of foreign bodies or bony fragments in head injury. Therefore ultrasound helps in planning precise microsurgical approaches.