Ultrasonic measurement of renal inclination; its importance in measurement of renal length

Abstract

In a group of 100 patients with no evidence of hepatic or renal disease, there is a wide angle variation which the right kidney makes with the horizontal plane when the patient is supine. This is probably of no significance in most patients. If renal angles vary similarly in patients having i.v. urograms [IVU], significant errors in measurement of renal length may result. These errors probably contribute to the wide range of normal renal lengths which are used for reference when making measurements from a IVU film. Since all errors represent underestimates of the correct length, the mean values for radiographic renal lengths are probably too small. In a significant minority of patients the influence of the renal angle on its length measurement will be sufficient to cause an incorrect diagnosis of an abnormally small kidney.