Removing a tumor from a patients brain is hard to do because, very often, brain tumors do not have boundaries that are easy for the patients surgeon to find. In many cases, the surgeon can't tell exactly where the tumor begins or ends. The surgeon usually can remove most of the patient's tumor by looking at the MRI images that were taken of the patient's brain before surgery. However, the surgeon does not have any good way to tell if the entire tumor has been removed or not. Removing the entire tumor is very important because leaving tumor behind may allow it to grow back which could decrease the chances of survival.

Inclusion Criteria:

• Preoperative diagnosis of either presumed first-time low or high grade glioma, or recurrent glioma, or metastasis, or meningioma
• Tumor judged to be suitable for open cranial resection based on preoperative imaging studies.
• Patient or LAR able to provide written informed consent.
• No serious associated psychiatric illnesses.
• Age > 21 years old.

Exclusion Criteria:

• Pregnant women or women who are breast feeding
• History of cutaneous photosensitivity, porphyria, hypersensitivity to porphyrins, photodermatosis, exfoliative dermatitis.
• History of liver disease within the last 12 months.
• Elevated liver function levels greater than 2.5 times the normal limit from laboratory tests conducted within 30 days prior to surgery.
• Inability to comply with the photosensitivity precautions associated with the study.
• Plasma creatinine in excess of 180umol/L within 30 days prior to surgery