A multifunctional stereotactic probe for laser-based tumour ablation in neurosurgery

The present treatment of deep seated brain tumours is mainly performed by radiotherapy and by stereotactic procedures which offer a high precision to hit the lesion, but the success of the operation may be limited as these methods do not facilitate the resection of tumour or necrotic tissue. A new minimal invasive approach promises to overcome this restriction. It is based on a new picosecond laser system which performs tissue ablation without unwanted thermal or mechanical side effects. In order to apply the laser pulses exactly to the target region a new mechatronic probe has been designed. Apart from transmitting the laser beam a safe operation of the system demands the performance of further functions. The design of the probe and its major components is described in this paper. A prototype has been constructed, which has a diameter of 5.5 mm and may be inserted into the skull up to a depth of 100 mm.