Long-term consumption of caffeine can induce ventriculomegaly. Caffeine (0.6 g/L) was added to the drinking water for 3 weeks (n = 72). A. Magnetic resonance images (T2-weighted) of rat brains in the coronal plane are presented anteroposteriorly from the striatum to the hippocampus. CSF in the ventricles appears white on the images. B. Measurement of relative cross section areas of the lateral ventricles by an image analysis program (MetaMorph). The relative area of the lateral ventricles was calculated as follows: area of lateral ventricles/total brain area*100.