Objectives: To assess brain lesion load and anatomical distribution in patients with juvenile clinically isolated syndrome (JCIS) and define MRI variables associated with rapid conversion to multiple sclerosis (MS).
Methods: JCIS was defined as the onset of neurological symptomatology suggestive of (MS) between 12 to 18 years of age. Patients were followed for one year after disease onset and those that experienced a second relapse were defined as rapid convertors to MS. Brain MRI data were analyzed at onset for lesion load, lesion volume and lesion localization, and compared between sustained JCIS patients and rapid convertors to MS.
Results: We studied 46 JCIS patients, 17 males and 29 females, mean+SE age at onset 15.8±0.4 years. JCIS patients that rapidly converted to MS (N=23) had higher disease burden as manifested by the total lesion volume and number at disease onset, and specifically higher number of brain lesions in the parietal lobe as compared to sustained JCIS patients (N=23). This was evident in the number of parietal T2 lesions (3.52±0.70 vs 1.3±0.49; p=0.003), FF (3.74±0.74 vs 1.30±0.49, p=0.003) and Gadolinium(Gd), (1.0±0.34 vs 0.09±0.06, p=0.004), respectively.
Conclusions: The presence of either two T2 lesions, three FF lesions or one Gd lesion in the parietal lobe at disease onset is associated with rapid JCIS conversion to MS.
