Diagnostic Tests

Computed tomography scan (also called a CT or CAT scan)
A diagnostic imaging procedure that uses a combination of x-rays and computer technology to produce cross-sectional images (often called slices), both horizontally and vertically, of the body. A CT scan shows detailed images of any part of the body, including the bones, muscles, fat and organs. CT scans are more detailed than general x-rays.

Brainstem Auditory Evoked Response (BAER)
The brainstem auditory evoked response (BAER) test measures responses in brain waves that are stimulated by a clicking sound to check the central auditory (hearing) pathways of the brainstem. The child will be asked to lie on a reclining chair or bed and remain still. Electrodes are placed on the scalp and on each earlobe. Clicking noises or tone bursts will be heard through earphones, and the electrodes pick up the brain's response and record it on a graph.

Magnetic resonance imaging (MRI)
A magnetic resonance imaging scan is usually called an MRI. It may also be called a nuclear magnetic resonance (NMR) or a magnetic field scan. It is a medical test that takes pictures of the inside of the body. Each picture or “slice” shows only a few layers of body tissue at a time. The MRI machine uses a large magnet and a computer to make pictures of your body. Pictures taken this way may help caregivers find and see problems in the body more easily. This test usually takes between 15 and 90 minutes.

Ultrasound (also called sonography)
A diagnostic imaging technique which uses high-frequency sound waves and a computer to create images of blood vessels, tissues and organs. Ultrasounds are used to view internal organs as they function, and to assess blood flow through various vessels.

Electroencephalography (EEG)
A non-invasive test that graphically records the electrical impulses of the brain cells. 

Brain SPECT
A SPECT scan integrates two technologies to view your body: computed tomography (CT) and a radioactive material (tracer). The tracer is what allows doctors to see how blood flows to tissues and organs. The computer collects the information emitted by the gamma rays and translates them into two-dimensional cross-sections. These cross-sections can be added back together to form a 3D image of your brain.

24-Hour ambulatory EEG
This test is used to distinguish non-epileptic from epileptic turns in situations where the child cannot be confined to a bed for inpatient or outpatient video EEG monitoring. It may be used to capture events that are situational.

Stereotactic surgery
Stereotactic surgery is brain surgery guided by CT scanning. The surgeon, viewing three-dimensional images, is able to deliver a single, high dose of radiation to the exact diseased location in the brain or spinal cord. This precise dose does not injure the areas of the brain closest to the tumor.

Stereotactic radiosurgery
Stereotactic radiosurgery uses sophisticated 3-D computerized imaging to precisely target a narrow x-ray beam and deliver a high concentrated dose of radiation to the affected area. Stereotactic radiosurgery is not surgery in the conventional sense because there is no incision involved and general anesthesia is not required for adults.

Polysomnogram
A polysomnograph is a test of sleep cycles and stages through the use of continuous recordings of brain waves (EEG), electrical activity of muscles, eye movement (electrooculogram), breathing rate, blood pressure, blood oxygen saturation, and heart rhythm and direct observation of the person during sleep.

Pneumocardiogram with PH probe
This “sleep test” uses six channels to monitor an infant’s sleep pattern to check for reflux, periodic breathing, apnea, and heart rate abnormalities. The six channels include: ECG to monitor heart rate, a thermistor in the nose and above the lip to observe airflow from the nose and mouth, and actimeter in the hand to check for activity of the infant, pH probe inserted into the esophagus to measure the acidity of gastric contents which may indicate reflux, and an oxygen saturation monitor to watch for desaturation during sleep.