 Patients with either an aneurysm, compressive syndromes or pituitary and intracranial tumor will be enrolled in the study. By taking advantage of the natural fluorescence of indocyanine green ICG within the red spectrum and applying a light filter to the endoscope eyepiece and camera it will show as to whether this technique provides adequate visual information to differentiate perfusion in tumor and surrounding structures and to evaluate normal vessels for aneurysm and compressive syndromes procedures. 