Magnetic resonance imaging (MRI) plays an important role in the regular monitoring of disease activity for those affected by MS. In addition to a stable clinical course without relapses, no new inflammatory lesions should appear during the MRI check-ups. Multiple sclerosis, as an inflammatory disease of the central nervous system, affects both the brain and the spinal cord. Therefore, regular checks of both regions (brain and spinal cord) would naturally be desirable. Nevertheless, in clinical routine, usually only the findings of the brain are checked and regular imaging of the spinal cord is mostly dispensed with (unless there is initially a spinal focus). This approach sometimes meets with incomprehension among patients who wonder if monitoring of the brain is really sufficient for assessing their disease progression.
What is the significance of a brain MRI?
This is indeed a completely justified question. When diagnosing, both the MRI examination of the brain and that of the spinal cord are important for diagnostic and differential diagnostic aspects. And from a purely medical point of view, it would also make sense to regularly monitor activity in the brain and spinal cord. However, this would mean a considerable additional effort, as the brain and spinal cord are usually not imaged in the same session. Furthermore, imaging of the spinal cord is anything but trivial and the quality of spinal MRI examinations is sometimes poor – this can be related to swallowing artifacts, but also if large layer thicknesses are used for time reasons and the (important) transverse layer guidance is either limited to a few sections or is completely missing. Moreover, from my point of view, real spinal monitoring is only possible if a transverse layering of the entire spinal cord is always carried out.
In addition, activity in the spinal cord is usually noticed through clinical symptoms, as symptomatic regions in the spinal cord are much closer together than in the brain. Thus, one can often conclude from a stable clinical course that there is no inflammatory activity in the spinal cord.
Because of these circumstances, regular control imaging of the spinal cord is rather dispensed with and regular control imaging of the brain is preferred. Not only because brain imaging often shows changes without the person affected being symptomatic, but also because the images of the brain are technically easier to compare – provided a corresponding repositioning was carried out and thus comparable layers as in the previous examination were generated. The cranial MRI is thus used “pars pro toto” (the part for the whole) for the follow-up control of MS patients – and this has proven itself in clinical practice.
Since magnetic resonance imaging remains the most important tool for assessing the dynamics of the disease and evaluating the success of therapy, it is sometimes depressing how little energy is expended in performing and evaluating the recordings. It would be nice if radiologists were aware of their great responsibility in co-managing MS patients and adhered to the scientific consensus regarding layer guidance, sequences, and use of contrast agents when performing the recordings.
