Hi. Thanks for your query. Noted your history of getting ultrasonography as advised by Gastroenterologist and getting the report of extra-renal pelvis with mild fullness on the right kidney. Wants to know the meaning of this and the care that you have t take: The meaning is as follows: The pelvis of the kidney is the part of the urine collecting system of the kidney wherein this is the last of the which gets narrowed to form the ureter. In a normal person this part called pelvis is situated in the kidney which in your case is outside the confines of the kidney hence said to be extra-renal, outside the confines of kidney. This can be normal in many a persons but as seen in your case has mild fullness, which is not normal. Mild fullness of the renal pelvis is also called as calactesis or hydronephrosis. This can be due to blockage to the outflow of urine, usually at the junction of pelvis to the ureter called as pelvi-ureteric junction or in the ureter or at the junction of the ureter with urinary bladder called as uretero-vesical junction. Ultrasonography can show the obstructing lesion or a stone and so on. IF required you will need further investigations like intravenous pyelography and CT scan if required. Once a definite cause is found, it is necessary to to get this corrected as per the instructions of an Urologist.