FIG. 3. A and B, Sagittal FLAIR image (A) (10,007/189, TI = 2200; 5-mm-thick sections) in dog 2 immediately after injection of contrast agent (0.1 mmol/kg) reveals the expected low signal intensity of CSF in the fourth ventricle (arrow). Sagittal FLAIR image 30 minutes after contrast administration (B) shows that the CSF in the fourth ventricle is now isointense with surrounding brain (arrow)