Diagnosing MS can be complex because there are no symptoms, physical findings or laboratory tests that can, by themselves, determine if a person has MS. Your health care provider will perform a variety of tests to evaluate mental, emotional, physical and cognitive function. A medical history, a neurologic exam and various tests, including magnetic resonance imaging (MRI), evoked potentials (EP) and spinal fluid analysis, may be used. Blood tests may also be used to rule out other diagnoses.
MS symptoms can come and go, which can make it challenging to make an accurate diagnosis.
In order to make a diagnosis of MS, the physician may go through these steps.
- Show two or more separate damaged areas of the central nervous system — brain, spinal cord and optic nerves.
- Show damage in two or more places that happened one or more months apart.
- Rule out all other possible diagnoses.
If a person has a single episode of MS-like symptom(s) lasting at least 24 hours, that person is said to have clinically-isolated syndrome (CIS). A person with CIS may or may not develop MS.