Role of magnetic resonance imaging within diagnostic criteria for multiple sclerosis.

The diagnosis of multiple sclerosis (MS) has been improved in recent decades with the incorporation of paraclinical investigations in diagnostic workup. In the last 15 years, magnetic resonance imaging (MRI) has become an especially valuable tool for supporting MS diagnosis, and specific imaging criteria became fundamental to the guidelines for the diagnosis of MS published in 2001 by an international panel (IP). The new IP criteria include MRI evidence of dissemination in space and time, making it possible to diagnose MS after a single clinical episode. This review considers current evidence concerning the reliability of the new IP criteria for the diagnosis of relapsing-onset MS, discusses strengths and weaknesses of the criteria, and outlines areas which may need modification or should be the focus of future research directed toward improving diagnostic accuracy. It also makes practical recommendations when using MRI and the IP criteria in MS diagnosis, especially in patients with clinically isolated syndromes or atypical presentations. The IP criteria are timely and concrete and introduce an important concept to MS diagnosis. Future modifications, based on emerging evidence, should further facilitate their implementation and improve their accuracy. Copyright 2004 American Neurological Association