PT - JOURNAL ARTICLE AU - Calabrese, M. AU - Seppi, D. AU - Romualdi, C. AU - Rinaldi, F. AU - Alessio, S. AU - Perini, P. AU - Gallo, P. TI - Gray Matter Pathology in MS: A 3-Year Longitudinal Study in a Pediatric Population AID - 10.3174/ajnr.A3011 DP - 2012 Sep 01 TA - American Journal of Neuroradiology PG - 1507--1511 VI - 33 IP - 8 4099 - http://www.ajnr.org/content/33/8/1507.short 4100 - http://www.ajnr.org/content/33/8/1507.full SO - Am. J. Neuroradiol.2012 Sep 01; 33 AB - BACKGROUND AND PURPOSE: GM pathology is considered a major determinant of disability in MS, but the comprehension of its origin and progression rate is limited by the uncertainty of dating the biologic disease onset. Thus, we planned a longitudinal study aimed at analyzing and comparing cortical pathology in pediatric and adult MS patients at clinical onset. MATERIALS AND METHODS: Within 12 months from clinical onset, 35 patients with cMS and 57 with aMS were included in a longitudinal study. At T0, GMf and CL number and volume were analyzed. Percentages of Δ-GMf and number of new CLs were assessed every year for 3 years (T1-T3). Twenty-eight age- and sex-matched NCs constituted the reference population. RESULTS: At T0, GMf did not differ between cMS and NC (P = .18), while it was lower in patients with aMS compared with both NCs (P < .001) and patients with cMS (P < .001). The number of patients with CLs, as well as CL number and volume, were higher in patients with aMS than in those with cMS (P < .001). At T3, Δ-GMf was higher in both patients with cMS (1.6% ± 0.5%; range 0.7%–3.4%; P < .001) and aMS (1.6% ± 0.6%; range 0.6%–3.4%; P < .001) compared with NCs (0.7% ± 0.2%; range 0.4%–1.1%), whereas no difference was observed between patients with cMS and aMS (P = .93). Δ-GMf significantly correlated with increased CL volume (cMS: r = 0.46; aMS: r = 0.48) and with the appearance of new CLs (cMS: r = 0.51; aMS: r = 0.49). CONCLUSIONS: Our findings suggest that focal (CLs) and diffuse (atrophy) GM damage are strictly associated with the biologic onset of MS, and proceed linearly and partly independently of WM pathology. aMSadult-onset multiple sclerosisCLcortical lesioncMSchildhood-onset multiple sclerosisEDSSExpanded Disability Status ScaleGMgray matterGMfgray matter fractionΔ-GMfdelta gray matter fractionΔ-GMf_1delta gray matter fraction at T1Δ-GMf_2delta gray matter fraction at T2Δ-GMf_3delta gray matter fraction at T3NChealthy controlT0baselineT2WMLVT2 white matter lesion volume