Effect of body position on ultrasonographic estimations of bladder volume

A study was undertaken to determine the effect of body position on ultrason ographic bladder measurements and volume estimations. Of the 42 dogs studie d, 15 were fresh canine cadavers without urological disease and the remaini ng 27 were undergoing investigations for disorders of the lower urinary tra ct. Bladder volume was estimated using a formula described previously. Irre spective of whether all dogs were considered together or only live animals were included, measurements made in dorsal recumbency tended to underestima te bladder volume while those made in right lateral recumbency resulted in overestimation. This was due to significant differences in all linear measu rements, apart from width, between body positions. Measurements in right la teral recumbency were higher than those in dorsal recumbency, In all animal s and in living dogs alone, bladder measurements in dorsal recumbency appea red to give a more accurate estimation of actual bladder volume.