Ultrasound-guided burr-hole biopsies in deep and diffuse brain lesions

Objectives: In contrast to stereotaxy, ultrasound-guided brain biopsies through a single burr hole provide a real-time imaging and do not require contrast media. However, it has been reported that this technique may be inadequate for deep lesions, especially lymphomas.

Methods: We analysed 43 ultrasound guided brain tissue biopsies performed in our department within the last two years. Through a single burr-hole with a diameter of 11mm, a 6×9mm ultrasound probe was used to perform needle biopsies of different brain regions. The needle was attched to the probe by a guiding device, which was fixed at the neurosurgical head-holder, thus allowing a safe, stereotaxy-like procedure.

Results: Among the 43 procedures, there were 8 lesions deeper than 5cm from the probe. 6/43 lesions were lymphomas. There were no false negative results. Three biopsies revealed unspecific tissue. However, these lesions did not enlarge within the next year. Two intraoperative haemorrhages could be identified during the operation.

Conclusion: This technique proved to have a high sensitivity and specifity, allowing a safe brain biopsy even in deeper and diffuse lesions.