ACCUMULATION OF HYPOINTENSE LESIONS (BLACK-HOLES) ON T-1 SPIN-ECHO MRI CORRELATES WITH DISEASE PROGRESSION IN MULTIPLE-SCLEROSIS

MRI findings are increasingly used as outcome measures in therapeutic trials in MS. The discrepancy between the extent of the lesions on con ventional T-2 images and the clinical condition of the patient is one of the problems encountered in such studies. This clinical-radiologica l paradox prevents the use of MRI data as surrogate markers of disabil ity in MS. A recent pilot study suggested a relationship between hypoi ntense lesions on T-1 MRI and disability. To assess in more detail the correlation of changes in hypointense lesion load on T-1-weighted spi n-echo MR images (''black holes'') with changes in disability in MS, w e studied 46 patients with clinically definite MS at baseline and afte r a median follow-up of 40 months. There was a significant correlation between baseline disability and hypointense lesion load (Spearman ran k correlation coefficient [SRCC] = 0.46, p = 0.001). in secondary prog ressive patients, the rate of accumulation of these ''black holes'' wa s significantly related to progression rate (SRCC = 0.81, p < 0.0001). We speculate that the appearance of hypointense lesions is the MRI eq uivalent of a failure of remission. Overall, T-1 lesion load measureme nts correlated better with clinical assessments than T-2 lesion load m easurements. Quantification of hypointense lesion load on T-1-weighted spin-echo MRI helps to resolve the clinical-radiological paradox betw een disability and MRI and has the potential to be a surrogate marker of disability in MS.