Cranial computed tomography (CT) was performed in three different samples of young women with anorexia nervosa before and after treatment. The biggest changes in cerebrospinal fluid volume were observed in the supratentorial and extracerebral-subarachnoid area, with smaller changes in the ventricles. These changes, as assessed by different methods of volumetric and planimetric measurement, were statistically significant and were correlated with the changes in body weight. Two patient groups could be distinguished on the basis of the presence or absence of cerebellar pseudoatrophy in the initial CT, and these groups also showed differences in preclinical and clinical course.