Multiple sclerosis, or MS, can be difficult to diagnose. Your healthcare providers must first rule out neurological diseases that manifest with similar symptoms. If you’re struggling with uncomfortable, unexplained symptoms, an accurate diagnosis made as quickly as possible is important for your physical and psychological well-being. Here are some of the tools neurologists use to evaluate those who present with symptoms of MS.
Because there’s no one definitive test used to diagnose MS, doctors must use a combination of strategies. Neurologists adhere to the McDonald Criteria, which indicate that to make an MS diagnosis, physicians must do all of the following:
- Find evidence of damage in at least two separate areas of the central nervous system (CNS), which includes the brain, spinal cord and optic nerves.
- Find evidence that the damage occurred at two different points in time.
- Rule out all other possible diagnoses.
If MS is suspected, the patient will undergo a range of tests to evaluate mental, emotional and language functions, movement and coordination, balance, and vision. The physician will also review his or her medical and neurological history, which can also provide evidence to meet the McDonald criteria. Blood tests can be used to rule out other conditions that have similar symptoms, such as Lyme disease.
The McDonald Criteria also provides specific guidelines for using magnetic resonance imaging (MRI), cerebrospinal fluid (CSF) analysis, and visual evoked potentials (EP). These modalities are used to look for evidence of brain damage in a patient who has only had one episode of MS-like symptoms, a phenomenon known as a clinically-isolated syndrome (CIS). In some cases, CIS is an early indicator of MS.
The MRI is used to view the brain and spinal cord to identify any inflammation or lesions that could be caused by the progression of MS. However, these areas don’t show up in about 5 percent of those with MS, and can also be caused by conditions like high blood pressure or diabetes.
The CSF, or spinal tap, samples cerebrospinal fluid to test for proteins and substances that could indicate the presence of MS. The EP is a test in which painless electrical pulses are used to measure the brain’s responsiveness to certain stimuli.