Radiology tests for multiple sclerosis

 Multiple sclerosis is a chronic health condition in which there is damage to myelin, the covering that protects the nerve cells in a person’s brain and spinal cord. The damage is visible on an MRI scan.

These changes disrupt the communications between the brain and the rest of the body, leading to a range of symptoms.

The symptoms vary between individuals but can include pain and tingling in the limbs, vision problems, bowel and bladder function disorders, difficulty walking, fatigue, and weakness or numbness in the body.

There is currently no cure for multiple sclerosis (MS), but medication may improve the long-term outlook in some cases. Current guidelines recommend starting treatment as early as possible for maximum effectiveness.

To do this, however, it is crucial to have an accurate diagnosis. No single test can diagnose MS definitively, but imaging tests and spinal fluid analysis can help doctors identify the condition.

Doctors often use an MRI scan to examine the brain and spinal cord and identify any damage that may indicate MS. They also use imaging tests to track the progression of the disease over time.

Radiology in MS diagnosis

Doctors do not know exactly why MS happens, but it appears to occur when the immune system mistakenly attacks the myelin sheath that protects the nerve cells.

The resulting lesions, or areas of scarring, are visible on MRI scans of the brain and spinal cord.

MS can be difficult to diagnose because it shares symptoms with other conditions and does not affect everyone in the same way.

It is important that a person gets a correct diagnosis as soon as possible so that they can start appropriate treatment.

Criteria

Doctors use specific guidelines called the McDonald criteria to decide whether a person has MS.

Before confirming a diagnosis of MS, a doctor must identify indicators of lesions or damage in at least two areas of the brain, spinal cord, or optic nerves.

There must also be evidence that the damage to each of these lesions took place at a different time. A lesion that has existed for some time will usually look different than a recently formed one.

In addition, a person must have experienced an attack of symptoms that lasted 24 hours or more without recovery and did not occur alongside signs of fever or infection.

Ruling out other conditions

Further tests can help rule out other conditions that may have similar symptoms, such as:

• severe vitamin B-12 deficiency
• collagen vascular disease
• Guillain-Barré syndrome

In one particular type of MS, known as clinically isolated syndrome (CIS), a person can experience one episode of MS-like damage but then never notice any further symptoms.

What to expect

Before having an MRI, a person will need to sign a consent form to say they agree to the test, and the radiologist will ask a number of questions.

The person may need to wear a gown, and they will have to remove any metallic jewelry, hearing aids, or metal items they may be wearing, because the procedure involves a strong magnet.

A person who wears a pacemaker or who has any type of metal in their body should know the details of these devices, to be able to explain to the healthcare professional. Some devices are acceptable during an MRI, but others are not.

An MRI scan is painless, but generating the magnetic field can be very loud. The noises sound like tapping and thumping. Earplugs can help make the noise more manageable.

People with claustrophobia may feel uncomfortable or anxious inside the tube-like MRI machine. Some MRI machines are open and do not have a tunnel, but these do not always produce such high-quality images.

Therefore, most doctors recommend the tunnel-like MRI for MS detection. They will sometimes give a person medication before the test to help reduce anxiety.

The MRI test can last from 15 minutes to an hour or more.

After the test, a person can usually return to their everyday activities. If they received sedation medications, they might need help from another person to get home.

Source: Medical News Today