Recently we had a patient arrive at Spectrum Diagnostic Imaging of Ohio. She was brought to our center for an MRA of the brain.
MRA stands for Magnetic Resonance Angiography. It is an MRI technique that specifically evaluates vessels such as arteries. Brain MRAs evaluate the vessels of the brain to look for aneurysms, vascular malformations such as AVMs, narrowing and blockage of the vessels of the brain, among others.
Brain MRAs are typically ordered for many different symptoms to exclude an aneurysm or vascular malformation, or search for a source of bleed. They are also used during the evaluation of stroke to detect blockages and narrowing of the arteries that feed the brain. Below are a few common diagnoses that Brain MRAs can pick up.
Aneurysm - Aneurysms are ballooning of vessels that risk rupturing. If blood leaks from the aneurysm patients describe the headache as a thunderclap and sharp/shooting pains. Patients can also have stroke-like symptoms with weakness, slurred speech and confusion. MRAs can detect most aneurysms though if the aneurysm is small or has collapsed, it may not be identified by this study.
Stroke - Also known as a "brain attack", stroke refers to a blocked artery that deprives a part of the brain of blood (and therefore oxygen). This part of the brain loses it function and patients present with weakness, slurred speech, difficulty walking and on occasion, headaches. MRAs evaluate the extent of atherosclerosis and can detect any significant blockages.
AVM - AVM stands for arteriovenous malformation. This is essentially a nest of abnormal vessels which grows in the brain. The vessels of AVMs are like "varicose veins" with thin walls but are subjected to high pressure blood flow, so risk rupture, much like an aneurysm. They can also act like tumors in that if large enough they compress nearby brain tissue. AVMs can also form aneurysms in or near them. Patients will experience headaches, stroke-like symptoms or seizures.
This particular patient had stroke like symptoms but had been stabilized at the hospital and released. Her Neurologist ordered an MRA to be done as soon as possible. She was fit in the same evening and results of her study were called in to her neurologist that evening.
An MRA of the brain can evaluate:
Internal Carotid Arteries
The carotid vessels arise from the aorta in the chest and travel up the neck along both sides. The vessel splits in the neck with the "internal" segments feeding roughly the front 2/3 of brain tissue.
Basilar Artery
The basilar artery is made up by two vertebral arteries which arise from vessels in the chest and travel up along both sides of the neck near the spine. This vessel feeds the brain stem and approximately the back 1/3 of the brain.
Circle of Willis
This refers to the group of vessels that are at the base of the skull that feed the brain. These vessels are formed by branches of the internal carotids and the basilar artery. Brain MRA scans can also be called MRA COW (Circle of Willis).
Brain matter
The white and gray matter of the brain are partially seen. Parts of the pituitary gland, optic nerves and upper brain stem are also evaluated.
If your doctor orders a Brain MRA Scan: Here is what to expect.
A Brain MRA generally takes about 20 minutes or so to complete. If you are going for one, wear loose comfortable clothing and remember to remove all metal (jewelry, phones, rings, etc) before going into the MRI scan room. This test is occasionally done with IV Contrast.
If you are using your insurance, you may need to have the exam pre-authorized (approved) by your insurance company first. If you're uninsured we offer discounted rates. You may call our scheduling department at 1-800-644-SCAN to request a rate and to schedule an appointment.
Recently we had a patient arrive at Spectrum Diagnostic Imaging of Ohio who was referred to us for an MRI of the Cervical Spine.
MRI Scans are frequently used to evaluate the structures of the cervical spine, also known as the upper neck. A variety of trends have increased the use of MRI in evaluating the spine - more sports activity, computer use, and we've remained much more active into our later years than previous generations.
If you've injured your neck or have chronic neck pain, your doctor will probably first order an X-Ray, this will rule out any fractures. After an X-Ray, an MRI may be needed to evaluate the internal structures of the cervical spine. The doctor's order for the MRI will ask us to rule out or comment on:
"r/o disc disease" - this refers to the discs that act as shock absorbers between the vertebral bodies of the spine. They can be injured or "flatten" over time and bulge and press on nerve roots. These are the dark flat structures between the tall, somewhat square gray bones (the vertebral bodies) in the picture to the right.
"r/o herniation"- this refers to a disc herniation. If the outer part of the disc tears, a jelly like substance can escape out (aka herniate) and cause radiating pain or weakness in the neck, shouder, arm or hand.
"r/o stenosis" - this refers to narrowing of the spinal canal and openings for the nerve roots. Bulging discs and other degenerative changes of the spine can narrow the spinal canal, causing neck pain or weakness. In the picture you can see the spinal cord as the long light grey structure, just behind the vertebral bodies, surrounded by white fluid.
An MRI of the cervical spine will evaluate:
Bones
A cervical spine MRI will include the cervical vertebral bodies, lamina, facets, spinous process and parts of the upper thoracic spine and lower brain. The cervical spine MRI can detect bone fractures, tumors, infection and evaluate post-surgical changes. An MRI also determines the extent of degenerative changes (arthritis) and be used for pre-operative planning for spinal fusion.
Discs
Cervcial spine MRIs are very good at looking at the discs between your vertebral bodies. A cervical spine MRI can detect disc flattening, bulges, herniations, and infection (aka discitis).
Spinal Canal and Neural Foramina
Spinal nerves arise from spinal cord and leave the spinal canal through holes called the neural foramina. The canal and these exit points can be blocked and cause neck, shoulder, arm, hand pain or weakness.
Cerebellum and Brain Stem
Parts of the lower brain including the cerebellum are seen. Some cerebellar conditions such as Chiari malformations can present with neck pain. The brain stem is continuous with the upper cervical spinal cord though usually not a cause of issues with the cervical spine. In the picture the cerebellum is the cauliflower shaped structure and the brainstem is the tissue just in front of it.
Soft Tissues
This refers to the muscles and tissues around your cervical spine. The cervical spine MRI can detect infections, fluid collections and tumors of these structures.
If your doctor orders a Cervical MRI Scan: Here is what to expect.
A cervical spine MRI generally takes about 20-30 minutes or so to complete If you are coming in for an MRI, wear loose comfortable clothing and remember to remove all metal (jewelry, phones, rings, etc) before going into the MRI scan room. If you've had surgery or have a history of cancer, you'll probably have the test done with contrast.
If you are using your insurance, you may need to have the exam pre-authorized (approved) by your insurance company first. If you're uninsured we offer discounted rates. You may call our scheduling department at 1-800-644-SCAN to request a rate and to schedule an appointment.