Initial clinical experience with a combined pulsed holmium-neodymium-YAG laser in minimally invasive neurosurgery

Various biophysical features of the laser beam have already been utilized i n clinical neurosurgery. However, the application of this therapeutic modal ity has by no means been overexploited. The history of laser application in neurosurgery has shown that there is no universal laser system capable of performing all surgical tasks in a suitable manner. The best results in tra ditional neurosurgery were achieved with instruments combining various wave lengths, such as the CO, and neodymium-YAG lasers. A pulsed holmium-YAC and neodymium-YAG (Ho:YAG and Nd:YAC) combined laser have been recently develo ped to meet the special requirements of minimally invasive neurosurgery. Th e system consists of a compact double-crystal single-head solid-state laser system generating 2 different wavelengths (Ho:YAG 2.08 mu m and Nd:YAC 1.0 5 mu m), selected for their capabilities of efficient coagulation and ablat ion. The two wavelengths are coupled into a common flexible optical fiber, which allows endoscopic application. The wavelengths can act simultaneously or separately without any interchange of the instruments. The system was e mployed first for experimental and subsequently for clinical purposes, prim arily for endoscopic operations. In this work the initial clinical experien ce is reported. The excellent haemostatic properties of the Nd:YAG laser an d the ablative properties of the Ho:YAC laser were confirmed. It was conclu ded that simultaneous application of the two laser modalities within one fl exible fiber offers new perspectives in tissue handling in endoscopic neuro surgery and as in open microsurgery.