The advent of magnetic resonance imaging (MRI) has been one of the most important advances in the understanding of multiple sclerosis (MS) over the past 25 years. Arguably, current MS therapies would not exist without MRI confirmation of their efficacy. The capabilities of MRI have captured the imaginations of clinicians and researchers and have helped spark increasing interest in the field of neuroimmunology.
Nonetheless, an uneasiness regarding the relationship of MRI findings to MS was present from the beginning. Although modest correlations could be made between MRI results and MS symptoms and disability in a population-based approach, it was difficult to translate these to an individual patient. The “MRI paradox,” that lesions identified on routine MRI do not correlate well with patient symptoms and neurologic signs, is evident not just to researchers, but also to individual practicing clinicians. Thus, new and refined imaging techniques for MS have been under continual evaluation. These include measurements of central nervous system atrophy, T1 hypointensities, MR spectroscopy, magnetization transfer ratio, and diffusion-weighted imaging. In particular, T1 hypointensities or “black holes” gained attention in the mid 1990s as a useful measurement that possibly correlated with disability. A large volume of literature has accumulated regarding black holes in MS, some of which appears to be factual, others of which are supported by insufficient evidence to accept as fact. Here we review some key points.
Naismith RT, Cross AH. Multiple Sclerosis and Black HolesConnecting the Pixels. Arch Neurol. 2005;62(11):1666-1668. doi:10.1001/archneur.62.11.1666