Optic Neuritis as the First Attack of Multiple Sclerosis

To determine the clinical and paraclinical features of multiple sclerosis (MS) in patients presenting for the first time with optic neuritis. In this descriptive study, 35 patients with clinical evidence of optic neuritis were enrolled. Our evaluation included a neurological examination, visual evoked potentials (VEP), brainstem-auditory evoked potentials (BAEP), and brain MRI. Mean patient's age was 27.498.43 years (range 14-51) including 30 female (85.8%) and 5 male (14.2%) subjects. Of 35 cases, 19 (54%) had other clinical signs of MS on neurological examination including loss of abdominal reflexes and presence of Babinski sign, 27 (77%) had abnormal brain MRI, 12 (34%) had abnormal VEP in the unaffected fellow eyes, and 4 (11%) had abnormal BAEP. The frequency of optic neuritis as the first manifestation of MS in our study was more than twice that in other countries. So it is recommended that all optic neuritis patients be referred to a neurologist for evaluation for MS.