 It is possible to detect tumor cells by making them glow with a specific color of light a process called fluorescence. This can be done by having you take the drug, ALA, before your surgery. ALA is a molecule that already exists in the cells of your body. Once enough of it is in your body, it gets converted into another molecule named PpIX. If blue light is shined on a tumor that has enough PpIX, it will glow with red light fluorescence that can be detected with a special camera. In this study, we want to determine how the fluorescence red light is related to the tumor which appears in the images that are normally taken of your brain which the surgeon uses to guide the removal of your tumor and the tumor tissue that will be removed during your surgery. Removing the entire tumor is very important because leaving tumor behind may allow it to grow back which could decrease your chances of survival. 