Figure 2.

MRI set up for Phase 1 preliminary studies (a) Illustration of rat positioned supine with the 1-cm radio-frequency (RF) surface coil posited at the left side of the rat’s head. (b) Illustration of position of the rat after CSF administration of gadoteric acid. The catheter is left in place after infusion. (c) Illustration of the left-hemispheric field-of-view captured with the RF coil positioning. Scale bar 3 mm. (d) Representative T2-weighted MRI at the level of the ventral hippocampus from a SHRSP rat. The white arrows point to PVS-like hyperintensity lesions in the hippocampus. The red box highlights the area shown in f. (e) Corresponding T1-weighted MRI from the same rat shown in d, after CSF administration of gadoteric acid. The white arrows highlight spot-like hyperintensity areas in the hippocampus. The red box highlights the same hyperintensity area as shown in d and g. Scale bars for d, e = 1 mm and (f) PVS-like hyperintensity lesion from the T2-weighted image magnified, showing the dark vessel (red arrow) and the moon-shaped PVS around it with high signal due to fluid accumulation. (g) the same PVS-like hyperintensity area is shown on the contrast enhanced T1-weighted MRIs acquired at an in-plane resolution of 0.15 mm². The lesion measures ∼200–300 µm across. Scale bars for f, g = 300 µm.