evaluation of the effect of patient position on sonographic renal length measurement in children under 18 years old.

introduction: renal length as measured on sonography is fundamental in diagnosis & follow up of renal diseases, and there’s increasing use of this kind of examination nowadays. some radiologists believe in the effect of position on renal measurements. regarding the above mentioned facts and in order to compare effect of patient position on sonographic measurement of renal length, this study was performed on children (under 18 years old) referred to taleghani and shohadaie tajrish hospitals from october 2001 through october 2002. methods and materials: in this clinical trial ,one hundred children were sequentially selected. all of them (or their parents) announced their agreement for sonographic examination. the observer measured the largest longitudinal renal diameter in three positions supine, coronal and prone. two measurements were obtained in each position and the larger one was recorded. if it wasn’t possible to get the desirable measurement in one position, it was also taken into consideration. the results were judged with anova tests. results: of the 100 patients investigated, 52 were boys & 48 were girls. in sagittal view, the left kidney was not measurable in 33.3 % of girls & 38.5% of boys. the maximum difference in renal measurements in the three procedures and accordingly, right and lsft kidneys as well as boys and girls was 3.7%, which was not statistically significant. conclusion: patient’s position has no effect on renal length. it may not be possible to measure the renal diameter in the supine position of all patients. it seems that coronal position is more suitable than the others.