Relationship between CSF outflow resistance and ventricular volumes measured in the same rats (n = 16). These animals include kaolin and saline injected rats used in Figures 2A and 3. No volume measurements were made in intact animals. Please note that we measured CSF outflow resistance in 17 animals. However, the ventricular volume for one of these animals was not available. There was a significant positive correlation between CSF outflow resistance and ventricular volume (p = 0.001, Pearson correlation; r2 = 0.583).