ULTRASOUND-GUIDED CRANIOTOMY FOR MINIMALLY INVASIVE EXPOSURE OF CEREBRAL CONVEXITY LESIONS

The authors describe a method of real-time ultrasound-guided craniotom y for an approach to cerebral convexity lesions. During surgery, a spe cially designed high frequency (7.5 MHz) sector probe with a thin (11 mm), extended tip is used to image the cerebral lesion through a singl e burr-hole. The distance between burr-hole and lesion and the directi on of the target are then determined from the ultrasound images, and c raniotomy is completed with the aid of these parameters. Errors in the preoperative planning of the approach, which might result in incorrec t placement of the craniotomy, can easily be recognized and corrected at an early stage of the operation, before the craniotomy has been com pleted. This technique greatly improves the accuracy in placing cranio tomy flaps. Since the risk of misplacing the craniotomy is virtually e liminated in lesions which are identifiable on ultrasound images, the technique allows the surgeon to keep the skull opening as limited as p ossible.