Frontal and occipital horn width ratio for the evaluation of small and asymmetrical ventricles.

The aim of this study was the introduction of a new linear ventricular measurement which has a better correlation with ventricular volume than the commonly used linear measurements, especially in chronically shunted patients with small and/or asymmetrical ventricles. Ventricular volume, brain volume, Evans ratio, Schierman index, cella media index and frontal and occipital horn ratio were measured from CT scans of 57 shunted hydrocephalic patients and 20 normal control children. Four groups of patients were identified with regards to the ventricular size and symmetry (small, large, symmetrical and asymmetrical). A new linear measurement was defined as half of the ratio of the frontal and occipital ventricular width to that of the skull (frontal and occipital horn width ratio; FOHWR) and compared to other linear measurements in different patient groups. FOHWR showed better correlation with ventricular size and ventricular brain ratio than the ventricular linear measurements currently in use, especially in chronically shunted patients with small and/or asymmetrical ventricles.