The brachial plexus is a group of nerves that starts near the neck and goes through the shoulder. These nerves control feeling and movement in the arms and hands. When the brachial plexus is injured or affected by illness, it can cause pain, weakness, numbness, and muscle loss in the arm.
Doctors often use an MRI scan to look closely at the brachial plexus. MRI is the best way to see these nerves because it uses magnets and radio waves to create detailed pictures without radiation. The scan is painless and has no known side effects.
You might need a brachial plexus MRI if you have pain or injury in the shoulder or arm. Other reasons include numbness, weakness, or muscle shrinking in the upper limb.
In an MRI, the brachial plexus is seen around the anterior scalene muscle, which is in the neck. Different MRI views help doctors see the roots and branches of these nerves. On the images, a normal brachial plexus looks like nerve bundles surrounded by fat. If there is damage, doctors may see swelling, changes in nerve shape, or loss of normal fat around the nerves. Sometimes, tumors or infections can be detected as larger or unusual areas.
During the MRI scan, you will lie still while the machine takes pictures. The process is quiet but can be noisy. Some people feel anxious inside the scanner, and doctors can give medicine to help relax if needed. The scan usually takes 20 to 40 minutes. The technician can talk to you through a speaker during the whole process. You may feel warm in the area being scanned, which is normal.
Doctors ask for a brachial plexus MRI to check unexplained symptoms like pain, weakness, or feeling problems in the arm. It is also useful after cancer radiation or before surgery when there might be nerve injury or growths near the neck, collarbone, or armpit.
This simple test helps doctors find the cause of your arm problems and plan the right treatment.
