An year back I was detected with a calculi in my right kidney. They installed a stint and did lythotripsy to remove it. In the final sonography report they said that the calculi was completely removed but I had a mild hydronephrosis which will go away in around 6 months. Now, after an year I had another sonography and found that there was a moderate hydronephrosis still there. They suggested I get my blood creatinine test done. This test suggested normal level of blood creatinine. Please suggest what should I do now? What could be the reason for Hydronephrosis?