MS diagnosis according to the McDonald criteria
A definitive diagnosis of multiple sclerosis is based on the so-called McDonald criteria, named after the chairman of the international expert group which was the first to include magnetic resonance imaging as an procedure in combination with clinical, electrophysiological and laboratory chemical tests in the diagnostics of MS.
The main criterion for the diagnosis of MS is still a spatial and temporal dissemination of inflammatory lesions. Physicians speak of spatial dissemination when inflammatory lesions occur in more than one location in the central nervous system. Temporal dissemination means that new lesions develop in the course of the disease.
A suspected diagnosis of MS is made on the basis of the patient’s descriptions as well as a physical examination in which typical deficits are identified.
Diagnostic tool in the early phase of the disease: magnetic resonance tomography
In the early phase of diagnostics, the use of magnetic resonance imaging (MRI), a method in which layered pictures of the brain and spinal cord are made, is essential. With MRI it is possible to visualize and identify both temporal as well as spatial dissemination. Other diagnoses that can cause similar symptoms can also be ruled out.
For a diagnosis of MS laboratory chemical examination of cerebrospinal fluid (CSF) is also necessary. Electrophysiological tests, so-called evoked potentials, may also be helpful for detecting damage to the brain or spinal cord. To definitively rule out or clearly differentiate multiple sclerosis from other disorders, further blood tests are performed.
Generally, a diagnosis of multiple sclerosis always requires several diagnostic components – magnetic resonance imaging alone is not sufficient.