<qa>  What is the procedure that is identical to the well-developed and practiced technique of brain biopsyEach patient will undergo ILT. The procedure will be performed under anesthesia as per standard procedures. The surgical placement of the laser fiber is a procedure identical to the well-developed and practiced technique of brain biopsy. A hole approximately 1 cm in diameter will be drilled in the skull through which the laser fiber will be placed under image guidance to confirm the actual progress during the advance of the fiber. We will deliver energy at a rate and distribution of 1-12 wattscm for exposures less than 20 minutes. After the laser has been turned off, and the tissue cooled, MRI will show the region of ablation. As needed, the laser fiber will be movedre-located to assure that the total target has been ablated. After the treatment is complete, the fiber is withdrawn, final images are acquired and the surgical site is closed and dressed. On the day after the procedure, the patient will undergo a 24 hour follow-up MRI exam. There will be post-operative care as with any neurosurgical patient. 