Patients with a presumed high grade glioma (HGG) identified by clinical evaluation and radiological investigation have two initial surgical options; biopsy or resection. In certain situations, such as severe raised intra-cranial pressure, surgical resection is clinically indicated. Where surgical resection is not feasible, biopsy is the only reasonable option. Most patients fall somewhere between these extremes and in such circumstances it is uncertain which procedure offers the best surgical option for the patient. Opinion is divided regarding the relative risks and benefits of each procedure.