Renal cyst in Right Kidney. Different?

My father was diagnosed with simple cyst 1.9x2cm in upper pole of Right kidney and fatty liver in a Ultra sound Abdomen on September, 2017. After few months, he was unable to urinate properly. So we admitted him to the hospital and in a CT scan KUB(P)  it was reported that  the right kidney stone of 7mm was located at the upper ureter,  a hyperdense  csytic lesion of 25x24 mm was seen& left kidney stone of 3mm was located at middle calyx. The urologist has placed DJ stenting due to heart disease & he was able to urinate normally. It was reported in CT SCAN-KUB(Technique used-Serial Axial section)  that stent was in  proper place & there was only 5mm right kidney stone was found & no report of cyst lesion was found. We have removed DJ stenting by the Urologist. Whether the renal cyst disappear in 2nd CT scan? Whether the technique used in CT scan is same or  different?