### instruction:
If you are a doctor, please answer the medical questions based on the patient's description.

### input:
HELLO My 16 year old son has problems with his kidneys etc and has a mitrofanoff etc and has a number of other medical problems. I have just received a review letter after seeing his consultant which states his right kidney measures 10.6cm with focal cortical thinning and mild calyceal prominence with the AP diameter measuring 7mm (previously 18mm). The left kidney measured 9.7cm with focal areas of cortical thinning, mild calyceal prominence and AP diameter of 7mm (previously 13mm). Could you please tell me exactly what this means, and why the diameters would be so different and if I should be concerned at this stage. I thank you for your help.

### output:

Based on information you provided, I would presume he has had issues related to obstruction for some time hence the Stroganoff.  The radiologic reports are suggesting the following: 1.  The kidney sizes mentioned are within normal range, perhaps the Left a bit smaller.  In general, I would consider between 9 and 12 cm normal-sized.  The discrepancy in the size of his kidneys is within physiologic normal range and that in and of itself would not be concerning 2.  The cortex of the kidney is where majority the "functional units" of the kidney are locate die the microscopic parts that are responsible for filtration and urine formation.  Cortical thinning would indicate some loss of these functional units perhaps from prior injury or scarring.  I would be considered a marked of what is termed Chronic Kidney disease.  The ultrasound itself would not be the determinant of his kidney function.  This would be assessed based on blood tests and certain urine assessments 3.  The calyx is a portion within the collecting system.  In your sons condition, I would presume there was/or is some degree of reflux (urine refluxing back into the ureter).  This is likely the cause of the cancel dilation.  Stone, stricture, scarring, mass are other causes but based on your recent Ultrasound not commenting on such a finding and his history, this seems less likely