Steps in Making a Diagnosis
If your physician suspects your child may have a possible brain or spinal tumor, several things will start to happen. First, your child’s doctor will take an accurate and thorough medical history of your child. It is important that symptoms are described including length of time, when they occur, what may bring them on, what relieves symptoms or makes them worse, if symptoms are getting worse or if additional symptoms are developing. The doctor will then do a full exam including an assessment of your child’s neurological system. This will include testing the cranial nerves and various functions of the brain and spine.
Computed Tomography (CT)
Typically a computerized tomography (CT) scan is done first because it is quick and doesn’t require sedation. Although a CT scan gives less detail, it can identify a mass or lesion that could be causing the symptoms. A CT scan generates hundreds of images as the head moves through the doughnut shaped CT machine, resulting in a detailed image. Sometimes a liquid dye is administered intravenously to make abnormal tissue more obvious.
Magnetic Resonance Imaging (MRI)
If an abnormality is detected, an MRI (magnetic resonance imaging) scan is ordered that may provide more detail about the lesion/tumor identified on the CT. A liquid dye similar to that used during the CT may again be used to further enhance and give more specific data about the lesion/tumor. Unlike a CT scan, an MRI does not use X-rays. Instead, the magnetic field affects the atoms of the brain that the MRI picks up and sends signals back to a computer, which assembles a picture. Because different atoms have their own characteristic radio signals, the computer can distinguish between healthy and diseased tissue. The brain and entire spine may be scanned to look for tumor.
Laboratory tests such as a lumbar puncture (LP or spinal tap) may be performed to obtain and test cerebral spinal fluid (CSF) for the presence of tumor markers (substances found in patients with cancer). Tests may also be run on the blood in order to detect tumor markers. Tumor markers help diagnose cancer, predict a patient’s response to certain cancer therapies, check a patient’s response to treatment, or determine whether cancer has returned.
Although scans, spinal fluid and blood work may give the medical providers a clue as to what type of tumor your child may have, typically no final diagnosis can be made until the tissue obtained through biopsy or resection is sent to a pathologist who can then identify the type of tumor.
For more information on tests and procedures, see Diagnostic Care.