Size and volume charts of fetal kidney, renal pelvis and adrenal gland.

OBJECTIVE To establish reference curves for size and volume of the fetal kidney, renal pelvis and adrenal gland, as measured using ultrasound from the 15(th) week of gestation. METHODS This was a prospective, longitudinal study of 96 fetuses in low-risk singleton pregnancies, in which we performed serial ultrasound examinations at 4-week intervals. The length and anteroposterior and transverse diameters of both kidneys, the anteroposterior and transverse diameters of the renal pelvises and the length of the adrenal glands were measured three times at each examination, with the average being used for further analysis. Reference charts were constructed using multilevel statistical analysis and comparisons were made with previously published charts derived from cross-sectional data. RESULTS We present nomograms for fetal kidney dimensions and volume, renal pelvis dimensions and adrenal gland length. The new charts show differences in shape and have narrower percentile bands in comparison to previously published reference ranges. CONCLUSIONS These new charts of measurements of the fetal kidney, renal pelvis and adrenal gland, from a prospective, longitudinal study, may be useful in the diagnosis and assessment of pathology of the kidney and adrenal gland.