Predictive value of lesions for relapses in relapsing-remitting multiple sclerosis.

BACKGROUND AND PURPOSE Recent studies have suggested that enhancing lesions on contrast-enhanced T1-weighted MR images are predictive of impending exacerbations in cases of relapsing-remitting multiple sclerosis. We examined whether enhancing lesions, new enhancing lesions, and new hypointense lesions ("black holes") could accurately predict exacerbations in a cohort of 50 patients with relapsing-remitting multiple sclerosis within a time frame of up to 6 months. METHODS Data were obtained from 50 patients with relapsing-remitting disease. All patients underwent monthly MR imaging and clinical examinations for a period of 12 months. Putative predictors of clinical relapse were defined from enhancing lesions, new enhancing lesions, and new black hole outcomes, and their operating characteristics were studied. RESULTS Overall, the positive predictive values (PV+) of enhancing lesions, new enhancing lesions, or new black holes for an exacerbation did not exceed 0.25 and the negative predictive values (PV-) were all near 0.9. The best predictor for new enhancing lesions was the occurrence of new enhancing lesions in each of the previous 3 months (PV+: 0.79 [95% confidence interval, 0.651-0.900]; PV-: 0.83 [95% confidence interval, 0.751-0.887]). Similarly, new black holes were predicted best by the occurrence of new black holes in each of the previous 2 months (PV+: 0.54 [95% confidence interval: 0.372-0.697]; PV-: 0.85 [95% confidence interval, 0.790-0.896]). CONCLUSION None of the MR markers could predict an impending relapse with any reasonable degree of precision. Rather, the absence of MR markers is associated with a more favorable clinical course (ie, fewer relapses).