Figure 2. Ventricle enlargement coincides with gadolinium-enhancing lesions and precedes EAE clinical signs.

(A) T₁ map MRIs of a representative mouse brain show altered tissue relaxation due to blood-brain barrier disruption following administration of gadolinium-based contrast agent. Reduced tissue T₁ (purple) is apparent in the meninges, cerebellum, and periventricular regions already by day 5 p.i. Note that the brain images have been registered to the baseline image for quantification; therefore, changes in ventricle volume are not apparent in these images. (B) Quantification of global changes in tissue T₁ following gadolinium contrast administration were especially prominent in the cerebellum (n = 16). The ΔT₁ (precontrast – postcontrast values) was significantly increased from baseline at days 8–11 p.i. (P = 0.0030, ANOVA). (C) The ΔT₁ of the whole-brain was also significantly increased at days 8–11 p.i. (P = 0.0023, ANOVA). (D) Kaplan-Meier plots show that the time of onset of ventricle expansion and the time of maximal gadolinium enhancement significantly preceded the onset of EAE clinical signs (P = 0.0068 and P = 0.0005, respectively; log-rank test) and the time of maximal body weight loss (P = 0.008, P < 0.0001, respectively).