Chronic, hypointense black holes (BHs) are recognized as a sign of permanent damage in patients with multiple sclerosis. Although the effects of interferon beta-1b in reducing the formation of new BHs are established, it is not clear whether the drug may reduce BH duration after these lesions are formed.
To analyze the effects of interferon beta-1b in reducing the duration of T1 BHs in patients with multiple sclerosis.
Patients were clinically assessed and imaged monthly over a 36-month natural history phase and 36-month therapy phase. Numbers of contrast-enhanced lesions and newly formed BHs were counted on each scan. Each BH was counted until it was no longer seen.
Outpatient service of the Neuroimmunology Branch at the National Institutes of Health, Bethesda, Md.
Six patients with relapsing-remitting multiple sclerosis were included. One patient did not form any BHs during the therapy phase. Analyses were performed on the remaining 5 individuals.
Interferon beta-1b at the dosage of 8 million international units every other day.
Main Outcome Measures
Number and duration (in months) of newly formed BHs.
Rate of BH accumulation decreased with treatment (P = .01), but Kaplan-Meier models revealed that the duration of BHs did not shorten (χ21 = 2.47, P = .12).
Interferon beta-1b reduces the frequency of new BH formation but does not appear to decrease their duration in time. Analyses with larger patient cohorts are needed to confirm these preliminary findings.Published online September 12, 2005 (doi:10.1001/archneur.62.11.noc40499).