ABSTRACT
In planimetric analysis of pneumoencephalograms the state of the brain ventricles can be assessed on the basis of planimetric coefficients--ratio of the sizes of individual parts of the ventricles and the width of the cerebral skull. Each of the calculated coefficients reflects the state of an individual portion of the ventricles. A summated coefficient Q is introduced which calculation permits to compose a digital characteristics of the state of the lateral ventricles as a whole. The ratio of the transverse size of the skull to the width of the III ventricle was also calculated, which reflects more objectively the state of the ventricle than the measurement of its absolute width value. The normal values of the coefficients were calculated on pneumoencephalograms with unchanged brain ventricles. In various degrees of ventricular dilatation the coefficients were determined on the pneumoencephalograms with a pathologically altered ventricular system.