Ultrasound-guided aspiration of brain abscesses through a single burr hole

Surgical aspiration and/or drainage of brain abscesses is considered to be the first-line treatment for abscesses larger than 25 mm. This is ususally performed with the aid of CT-guided stereotaxy. A method of ultrasound guidance is presented that allows a single burr hole approach with real-time imaging of the whole procedure. A bayonet-like shaped ultrasound probe with tip dimension of 8 x 8 mm only (EUP-NS 32, Hitachi/Ecoscan) with frequencies of 3.5 and 5 MHz is used. After placement of a burr hole the target is identified by transdural insonation, a guideline is adjusted and a mounted puncture-adapter guides the cannula towards the lesion under real-time imaging control. Up to now 12 abscesses in 10 patients were treated. Visualization was always excellent. A second aspiration had to be performed twice. One abscess did not contain enough pus to be cured by aspiration and was removed by open surgery, another could not be tapped by the blunt cannula and was aspirated under stereotactic control using a sharp trocar. Outcome was excellent in 6 patients and fair in 2 patients but this was due to the pre-existing disease. Two patients admitted in deep coma died despite an emergency operation. The presented method has proven to be a very powerful guiding tool in the surgical treatment of brain abscesses through a single burr hole approach.