MRI of cortical lesions (gray matter on the surface of the brain*)due to MS has been hampered by the lesions’ small size and low contrast to adjacent, normal-appearing tissue.
Epub ahead of print: Bluestein et al. T1 and proton density at 7 T in patients with multiple sclerosis: an initial study. Magn Reson Imaging. 2011 Sep 19.
* the cortex of the brain is where specialised cognitive tasks occurs; MS lesions in the cortex are responsible for cognitive dysfunction (memory impairment, etc.) that occurs in the majority of MS’ers.
In this study 8 MS’ers and 7 healthy control subjects were scanned at 7 Tesla (most conventional MRI scanners are 1.5 or 3 Tesla; Tesla refers to power of the magnet).
Regions of interest were drawn in white matter, gray matter, cortical lesions, white matter lesions and cerebrospinal fluid.
White matter and gray matter lesions were significantly higher in MS’ers than in controls. Large numbers of cortical and white matter lesions were noted in MS for the first time.
Ultrahigh field MR imaging will be important for future investigations in MS research, particularly the detection of cortical lesions.
“The introduction of ultra high-field MRI will allow us to monitor the effects of MS in the cortex of the brain. Todate the lesions in this area have been invisible on MRI. We know from pathological studies that about 50% of the disease burden occurs in the gray matter. This study and other like it enlarges the iceberg that is MS; now we will be able to see more of the iceberg that is subclinical.”