ABSTRACT
Using Omnipaque CT cisternogram, author prospectively studied on the level of physiologic CSF reflux into ventricles in 42 cases, who had not history of brain pathology or abnormal findings in neurologic examination. Results were as follows: 1) Age of all cases ranged from 26 to 78 years and male to female ratio was 2.8:1. 2) Of 7 cases used control, 6 cases showed maximum reflux at 2 hours scan and remaining 1 showed at 5 hours. 3) CSF reflux to 4th ventricle were detected in all cases, but reflux to Aqueductus of sylvius, posterior 3rd ventricle, anterior 3rd ventricle, foramen Monro and lateral ventricle were in 17 out of all 42 cases(40.5%), 12/42(28.6%), 3/42(7.2%), 3/42(7.2%), 2/42(4.8%) respectively. 4) Cases with reflux to 4th ventricle could be considered as normal, but authors with reflux above 4th ventricle need follow-up scan after 3 to 6 hours to decide as normal.