|
Risk of MS low after optic neuritis if MRI is normal
Last Updated: 2008-06-20 12:37:58 -0400 (Reuters Health)
NEW YORK (Reuters Health) - If initial brain magnetic resonance imaging (MRI) findings are normal, the odds of developing multiple sclerosis (MS) after an acute episode of optic neuritis are only 25%, results of a 15-year, prospective follow-up study indicate. The risk is lowest if features of optic neuritis are atypical, the investigators report in the June Archives of Neurology, suggesting that prophylactic treatment can safely be withheld in the absence of other neurologic symptoms.
Robin L. Gal, at the Jaeb Center for Health Research in Tampa, Florida, and members of the Optic Neuritis Study Group enrolled 389 patients with acute unilateral optic neuritis between 1988 and 1991. The number of white matter lesions at least 3 mm in diameter was determined on unenhanced MRI of the brain at baseline.
The overall cumulative probability of developing MS after onset of optic neuritis during the ensuing 15 years was 50%. The presence of brain MRI lesions was the strongest predictor of risk -- 72% of patients with at least one lesion developed MS compared with 25% of those with no brain lesions at baseline.
Among patients without MS at the 10-year examination, the likelihood of developing MS within the next 5 years was 32% among those with brain lesions at baseline, the authors report. Only one patient without lesions developed new-onset MS after 10 years.
"Patients with abnormal brain MRI findings already have morphologic evidence of disseminated disease and could be considered to have MS at the time of the optic neuritis episode," Gal and associates advise. They recommend additional ancillary testing to determine if prophylactic treatment for these patients is appropriate.
Risk factors for progression to MS among those without brain lesions were female sex and retrobulbar neuritis.
By contrast, the investigators note, "both sexes had a low risk when atypical features of the optic neuritis were present, namely, no light perception in the affected eye, absence of periocular pain, and ophthalmoscopic findings of severe optic disc swelling, peripapillary hemorrhages, or retinal exudates."
For such patients, "the results certainly justify withholding treatment (specifically for MS) because many may never develop MS."
Arch Neurol 2008;65:727-732.
Archive
MS News is brought to you by the Consortium of MS Centers as part of the eMS-Health Project funded by an unrestricted grant from Teva Neuroscience.
Copyright © 2006 Reuters Limited. All rights reserved. Republication or redistribution of Reuters content, including by framing or similar means, is expressly prohibited without the prior written consent of Reuters. Reuters shall not be liable for any errors or delays in the content, or for any actions taken in reliance thereon. Reuters and the Reuters sphere logo are registered trademarks and trademarks of the Reuters group of companies around the world.
|
CMSC Online 
