This is a very interesting study that questions the accuracy of MRIs in diagnosing MS. Isn't one of the measures in the clinical trials of all these MS drugs the number of lesions that appear on an MRI??!! Hmmm...
Study Questions The Accuracy Of MRI In Diagnosis Of MS After First Neurologic Event
The accuracy of magnetic resonance imaging might not be great enough to confirm a diagnosis of MS, based on a single event of neurologic dysfunction, according to a study published online March 24 ahead of print in the British Medical Journal.
To evaluate the accuracy of MS diagnoses derived from MRI data, researchers examined data from a total of 29 studies that compared MRI with a reference standard for the diagnosis of MS. Two of these studies followed patients for more than 10 years.
The researchers found that many of the studies had methodological flaws that led their authors to overestimate the diagnostic accuracy of MRI.
Overall, patients with a first attack suggestive of MS experience an approximately 60 percent chance of developing MS. During a period of 10 to 14 years, the probability of developing clinically definite MS is increased to between 75 and 84 percent in patients with a positive MRI scan and is decreased to between 43 and 57 percent in patients with a negative scan, according to data from the two-long term studies.
The authors noted that the use of MRI to confirm MS based on a single attack of neurological dysfunction may lead to over-diagnosis and over-treatment of MS.
"Even in the presence of many lesions, MRI could not accurately rule multiple sclerosis in," the authors wrote. "Similarly, the absence of lesions was of limited utility in ruling out a diagnosis of multiple sclerosis."
"Neurologists should discuss with their patients the potential diagnosis, treatment and ultimate effect of potential errors of false positive and false negative MRI results," the authors concluded