Photoablation of meningiomas and neurinomas by Holmium Yag laser radiation

Cranial rat bone was irradiated by 2.1 mu m Holmium Yag laser radiation. Qu antitative edge rates were calculated. Histologic sections were investigate d by light and electron microscopy. Eighteen cases of hard fibrous or calci fied spinal and cranial meningiomas and neurinomas were operated upon using pulsed laser beam, in rat cranial bone ablation rate ranged between 0.3-0. 5 mm per pulse. Perifocal thermal damage was observed in a zone of 20-90 mu m around the lesion. In all human cases tumors could be removed totally wi thout additional neurological deficit. In vivo heat development was measure d by an i.r.-camera.