About a brachial plexus MRI scan
The brachial plexus is a network of nerves that starts from the spinal cord in the lower neck (the C5 to T1 nerve roots), passes behind the collarbone and through the armpit, and goes on to form the nerves of the arm. It controls movement and feeling in the shoulder, arm and hand.
When these nerves are injured, squeezed or inflamed, they can cause pain, numbness, tingling, weakness or wasting of the muscles in the shoulder, arm or hand. An MRI scan uses a strong magnetic field and radio waves, not X-rays, to show the nerves and the tissues around them in detail. It is the main imaging test for the brachial plexus and is usually requested by a neurologist, orthopaedic surgeon or other specialist, often alongside nerve conduction studies.
The scan usually covers the area from the lower neck to the armpit, and often both sides are imaged so they can be compared.
What happens during the scan
You lie on your back on the scanner bed, with a coil placed around your neck and shoulders. The scanner is loud, so you will wear ear plugs or headphones, and the radiographer can talk to you throughout. You need to keep still, and you may be asked not to swallow during some parts of the scan. Some scans include an injection of contrast dye (gadolinium) into a vein in your arm; where contrast is needed, it is charged separately.
What the scan can show
A brachial plexus MRI can help to look at:
- nerve injuries after trauma, such as a fall, sports injury or road traffic accident, including stretched or torn nerve roots
- compression of the nerves, for example in thoracic outlet syndrome, where nerves are squeezed between the neck, collarbone and first rib
- inflammation of the nerves, such as Parsonage-Turner syndrome (sudden severe shoulder pain followed by weakness)
- nerve damage after radiotherapy for cancers such as breast or lung cancer, and whether a cancer has come back
- lumps affecting the nerves, such as neurofibromas and schwannomas, or tumours spreading from nearby
- infection spreading to the nerves from nearby structures
Some nerve conditions, particularly inflammatory ones, may show only subtle changes on MRI, so your specialist will look at the scan together with your symptoms and nerve tests.
Preparing for your scan
No special preparation is usually needed, and you can eat and drink normally. If you have had nerve conduction studies or previous neck or shoulder scans, upload the reports when you book.
You can usually eat, drink and take your normal medicines unless the scanning centre tells you otherwise. Wear loose, comfortable clothing without metal zips or buttons, and leave jewellery at home. You will be asked to remove metal items such as hair clips, hearing aids, coins and keys, and you may be asked to change into a gown.
Before the scan you will complete a safety questionnaire. Tell the team if you have a pacemaker, any metal implant, surgical clips or other device, if you have kidney problems or allergies, or if you are, or might be, pregnant or breastfeeding. If you feel anxious in enclosed spaces, let us know when you book. Some centres can offer a relaxant, and if you take one you will need someone to take you home and must not drive for 24 hours.
Frequently asked questions
What symptoms can a brachial plexus problem cause?
Problems with the brachial plexus can cause pain, numbness, pins and needles, weakness or muscle wasting in the shoulder, arm or hand. Symptoms depend on which nerves are affected.
Is a brachial plexus MRI the same as a neck MRI?
No. A neck (cervical spine) MRI focuses on the spine, discs and spinal cord. A brachial plexus MRI follows the nerves after they leave the spine, from the side of the neck through to the armpit, using a different set of pictures.
Will I need a contrast injection?
Sometimes. It depends on what your doctor is looking for, for example if a tumour or inflammation is suspected. If contrast is needed, it is given through a small cannula in your arm and is charged separately.
Do I need a referral?
You can tell us if you have a referral from your GP, physiotherapist or consultant and upload it when you book. If you do not have one, select “no referral” when you book and the scanning centre will confirm the next steps with you.
Sources
- Magnetic resonance imaging of the brachial plexus. Part 1 (European Journal of Radiology Open, 2021)
- European Society of Radiology – Brachial plexus imaging (educational poster)
- NHS – MRI scan
The information on this page has been gathered from various sources and is provided for general information only. It is not medical advice. TOP MRI is not liable for the accuracy or completeness of this information. Please speak to your doctor or the scanning centre about your own situation.