Model studies on cast specimens of human right ventricles

50 cast specimens of right human ventricles were subjected to X-ray cinematography in biplane RAO/LAO projection. From the silhouettes in the two projection planes the volumes were calculated using various methods. The calculated volume values were compared with the true values determined by Archimedes' principle. The methods were then arranged in the order of their accuracy; as criteria the mean squared deviations, correlation coefficients and residual variance were used. The most accurate calculation of the right ventricular volume was obtained by using Ferlinz's method: V = 2/3 [(ARAO X ALAO)/LRAO] and by authors' own approach: V = ARAO X ALAO X LRAO X K, where K = 0.5 (A = area, L = length).