Sonographic standards for normal infant kidney length.

Standards for kidney length in relation to size were derived from measures of 34 normal, full-term, healthy infants aged 2-56 weeks. Of six general size variables (age, weight, length, head circumference, abdominal circumference, and C7 to coccyx length), net kidney length correlated best with a combination of infant length and weight. A nomogram has been generated from these data for use by the radiologist.