In most cases, surgeons perform a craniotomy, opening the skull to reach the tumor site. Surgery, by providing a debulking of the tumor, carries the ability to prolong the lives of some patients and improve the quality of remaining life. Surgery provides the ability to reduce the amount of solid tumor tissue within the brain, remove those cells in the center of the tumor that may be resistant to radiation and/or chemotherapy and reduce intracranial pressure. However, GBMs are surrounded by a zone of migrating, infiltrating tumor cells that invade surrounding tissues, making it impossible to ever remove the tumor entirely. The primary objective of surgery is to remove as much of the tumor as possible without injuring the surrounding normal brain tissue needed for normal neurological function. The mainstay of treatment for GBMs is surgery, followed by radiation and chemotherapy. The yellow/red signal displays significant activation in the left temporo-parietal region, in the expected anatomical area for language production and in close proximity to the location of a glioblastoma. For tumors that are localized in the proximity of critical areas (speech centers, motor cortex or visual cortex), fMRIs provide an important adjunct, particularly in regards to surgical planning. Activated brain is shown as a yellow/red signal (Figure 3) superimposed to an otherwise standard MRI. This is fundamental to define the regions of the brain which, if damaged, would cause problems to the patient. fMRI with BOLD imaging during object naming.įunctional MRI (fMRI): fMRI is a useful technique to find which parts of the brain become activated when the patient is asked to perform a certain task (for example, talking or moving one arm or leg). This technique can be considered as a non-invasive tissue sampling, although it is not as accurate or definitive as a standard biopsy.įigure 3. The opposite raises suspicion of a tumor. The output of this imaging modality is a diagram where it is possible to see the amount of each chemical in an area of the brain under analysis: If the amount of NAA is more than choline, that would suggest a normal brain (Figure 2). MRI spectroscopy (MRS): This is an imaging tool, based on MRI, that provides information on the chemical composition of the tumor and works based on the fact that certain chemicals are abundant in the normal brain, while others are abundant in tumors (for example, choline). MRI spectroscopy of normal brain (sampled voxels are represented on the right side of the panel).The NAA peak is the most prominent. Low-grade tumors usually do not show much contrast enhancement, while GBMs display strong contrast enhancement and frequent central necrosis (Figure 1).įigure 2. Other imaging sequences provide clues as to tumor cellularity, brain swelling and brain infiltration. becomes bright on images) is an indication of a higher-grade astrocytoma. As a rule of thumb, if the tumor picks up the contrast (i.e.

Usually, images are acquired both before and after the administration of IV contrast. Axial T1-weighted MRIs after IV gadolinium administration.Ĭonventional MRI: Magnetic resonance imaging (MRI) is the most important imaging study for astrocytoma. Magnetic resonance spectroscopy (MRS) is used to examine the tumor's chemical profile.įigure 1. Intraoperative MRI may also be useful during surgery to guide tissue biopsies and tumor removal. Diagnostic tools include computed tomography (CT or CAT scan) and magnetic resonance imaging (MRI). Sophisticated imaging techniques can accurately pinpoint the location of brain tumors.

Dead cells mutations