Neurologic Tests & Diagnosis

An electroencephalogram (EEG) measures the electrical activity of your brain. Our board-certified EEG providers offer 24/7 coverage for these types of EEG tests:

• Ambulatory (take-home) EEG monitoring with video
• Critical care continuous video-EEG (intensive care unit, or ICU, monitoring)
• Evoked potential studies (visual, auditory or somatosensory)
• High-density scalp EEG
• Inpatient continuous video-EEG (epilepsy monitoring unit)
• Intracranial subdural and depth EEG electrode monitoring
• Intraoperative electrocorticography
• Routine, extended and sleep-deprived EEG

BIDMC’s Center for Autonomic and Peripheral Nerve Disorders is an international center for these types of disorders. This portion of the nervous system controls automatic bodily functions, such as heart rate, blood pressure and sweating. It also affects bowel, bladder and sexual function.

If you need autonomic testing, you’ll participate in a series of painless, non-invasive assessments to help get an accurate diagnosis. We’ll measure your heart rate and blood pressure in response to a variety of stimuli, such as deep breathing and active/passive standing. We’ll also measure your sweat response to deep breathing and mild electrical stimuli.

Preparing for Your Autonomic Test

Here are tips on preparing for your autonomic test:

• Avoid alcohol and over-the-counter medications, like nasal decongestants, in the days before the test.
• Avoid cardiovascular medications for one to three days before the test.
• Avoid caffeine and any other artificial stimulants for at least six hours before the study.
• Eat a good meal about three hours prior to the study (but not within two hours) unless your doctor tells you otherwise. This is particularly important if you have diabetes.
• Wear a short-sleeved, loose-fitting top.

Please bring your insurance information and a list of your current medications (including dosages). When you arrive, you’ll fill out a short questionnaire about your symptoms and medical history.

Also called an arteriogram or catheter angiogram, this invasive test requires numbing anesthesia and a small incision (cut) in your groin. The doctor inserts a catheter (thin, flexible tube) through arteries from the groin to the neck then injects contrast dye into the bloodstream. The contrast highlights these or other abnormalities:

• Aneurysm
• Obstruction or narrowing in a blood vessel in the neck, head or brain
• Vascular malformation

This test can help diagnose stroke, unruptured and ruptured aneurysms, and other brain and spine vascular abnormalities. Angiography is the first step in endovascular treatment of these abnormalities. Doctors often perform angiogram before radiation or surgical therapy to treat cancer.

A head CT is an imaging procedure that examines the brain and its surrounding anatomy.

A head CT angiography is a specialized neuro CT scan that involves fast CT imaging while simultaneously injecting IV contrast into a vein in your arm. This allows us to visualize specific vascular anatomy of the organs in your body. Compared to a standard CT scan, this test produces clear and detailed images of the brain’s arteries.

The images help doctors detect and analyze aneurysms and other abnormalities of the blood vessels. Your doctor may use it to evaluate vessels or to plan surgery.

Preparing for Your CT Test

Don’t eat solid foods for at least three hours before your test. During this time, you may drink clear liquids and take your usual medications.

For your exam, you may receive IV contrast (dye). IV contrast is an iodine-based solution that a member of the testing team injects into your veins. The contrast appears bright white on a CT image. This contrast allows the radiologist to better see the blood vessels in your body. Your kidneys will filter IV contrast from your blood. You will then pass it — unnoticed — in your urine after the test.

It is important that you inform the technologist before your exam if you have any of these conditions:

• Had IV contrast before.
• Have asthma.
• Are allergic to any foods or medications.
• May be pregnant or are breastfeeding.
• Are diabetic and taking Glucophage (metformin).

During the CT Exam

You will enter the CT room and lie on a table. Depending on the area of your body that we are scanning, you may need to lie on your back or stomach. Like all CT exams, it is important that you hold very still during the study. This table will move in and out of the CT scanner (a large donut-shaped machine that is open on both ends) while capturing images.

Most CT scans take between 10 and 20 minutes to complete.

After the CT Exam

You can resume your normal daily routine after your exam. If you received IV contrast for your exam, be sure to drink extra fluids to help clear the material from your system.

Getting Your CT Test Results

One of our radiologists will review the images from your CT exam. They will send a report to your doctor. Your doctor should have access to your exam results within 24 hours.

Your doctor may order this test if they suspect a ruptured aneurysm (burst blood vessel). Using a needle, the doctor removes a small amount of fluid from the space between the spinal cord and its protective covering. If there is blood in the fluid, it indicates bleeding or brain hemorrhage. This likely would be a ruptured aneurysm.

This type of imaging uses MRI to visualize the brain’s arteries and veins. Depending on the information your doctor needs, you may or may not receive an IV injection. MRA can display 2D, 3D and 4D images of blood vessels.

We also have sophisticated CT-MRI image fusion technology. This process allows doctors to collect and combine your data from two different studies: CT and MRI. The resulting 3D image allows them to better see inside your body and diagnose your condition or plan for your treatment.

The study of neurogenetics includes everything related to the nervous system. Neurogeneticists help you and your family determine the cause of various rare neurological conditions. Your neurogenetic team can refer you or your loved one to counselors who can help you better understand and manage your condition.