Figure 1

The surgical procedure. (A) The ureteral catheter was connected to a mixed solution of 0.2% methylene blue saline (white arrow). (B) The cyst (white arrow) was positioned near the collecting system (black arrow). The perfused methylene blue stained the collection system, differentiating it from the cyst wall. (C) The renal parapelvic cyst was resected with no secondary damage. (D) The cyst was connected to the collection system and leakage of a blue liquid was seen from the cyst wall (white arrow).