Extrarenal pelvis

Last revised by Ammar Ashraf on 21 Dec 2022

Extrarenal pelvis refers to the presence of the renal pelvis outside the confines of the renal hilum; it is a normal anatomic variant.

It is found in ~10% of the population 2

An extrarenal pelvis usually appears dilated, erroneously suggesting obstructive pathology. Subsequent investigation with CT usually clarifies a false interpretation on ultrasound.

  • a normal extrarenal pelvis will demonstrate normal renal cortical thickness, bilateral symmetrical contrast excretion, and normal-appearing calyces 3

After evaluation with ultrasound and/or CT/MRI, if there is still confusion about whether a dilated renal pelvis is obstructed or not, renal scintigraphy can clarify

ADVERTISEMENT: Supporters see fewer/no ads

Updating… Please wait.

 Unable to process the form. Check for errors and try again.

 Thank you for updating your details.