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- Imaging
- • Radiological evaluation plays an important role in both the diagnosis and management of brain tumors. The
- images are used by the neurosurgeon to decide whether a biopsy or a surgical resection of the tumor should be
- performed. The scans are repeated during the course of treatment to assess how the tumor is responding. The
- exact study chosen will depend upon the preferences of the treating physicians and may be influenced by the
- results of an initial scan.
- • MRI and CT scans are the most often used. MRI images provide better definition between normal brain and
- tumors and can better depict the swelling associated with these tumors. MRI scans produce a
- three-dimensional image of the brain but can take over an hour to complete. The patient must hold very still in
- a tight space, which some find uncomfortable and confining.
- A CT scan takes only minutes to complete but does not provide images with as much detail as MRI. CT
- scans provide superior images of calcified tumors and the skull. Contrast substances injected into a vein just
- before an MRI or CT scan is performed will cause some tumors to be enhanced so that they can be better
- defined. When a tumor is suspected, scans are usually performed both before and after contrast has been given.
- • A tumor may be found near important blood vessels or have characteristics that suggest that it could be
- derived from a blood vessel. In these circumstances, a blood vessel study (angiogram) is performed. Dye is
- injected into the major feeding arteries of the brain and x-rays are taken.
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