Figure 8

Quantitative MRI analysis of brainstem volume of Wfs1-ex5-KO232 rats. The medulla was manually traced by an observer blinded to the genotypes of the rats from T2 images using ITK-SNAP software. The volumes of the segmented structures were calculated as volume per slice from bregma level −9.48 to −15.48 mm. (a) The total volume of the medulla and (b) volume of the extraparenchymal space (EPS). Volumes of individual MRI slices from (c) 8-month- and (d) 15–month-old animals. The volume of the extraparenchymal space is increased at the level of the inferior olive (IO) in Wfs1-ex5-KO232 rats at 15 months. Line shows localization of IO (bregma −12.00 until −14.76 mm). Representative T2-weighted MR images of the medulla of wild-type (WT) and Wfs1-ex5-KO232 rats are taken at the level of the IO (bregma approx. −12.63 mm). (e,f) There are no significant changes in medullary volume at 8 months of age. At 15 months of age, the ventral surface of the medulla appear more concave (arrowhead) in (h) Wfs1-ex5-KO232 rats than in (g) WT littermates. (h) The area of the extraparenchymal space surrounding the medulla is also increased in Wfs1-ex5-KO232 rats. The data were compared using two-way ANOVAs followed by Fisher’s LSD tests; *p < 0.05, **p < 0.01 between genotypes. The data are presented as the mean ± SEM, n = 6–7.