[Ureteral Access Sheath Assisted Percutaneous Antegrade Ureteroscopic Lithotripsy for Impacted Ureteral Calculus]

We retrospectively evaluated the safety and effectiveness of ureteral access sheath-assisted percutaneous antegrade ureteroscopic lithotripsy in treating ureteral calculus. Between January 2016 and April 2022, 28 patients with ureteral calculus received ureteral access sheath-assisted percutaneous antegrade ureteroscopic lithotripsy. At postoperative 1 month, a plain computed tomography (CT) and kidney ureter bladder X-ray (KUB) were performed to assess stone fragmentation and hydronephrosis. According to postoperative imaging, stone-free was defined as residual fragments 4 mm or less on KUB and 2 mm or less on CT. The mean stone size was 16.3 mm (3-43 mm). The mean stone volume was 1.91 ml (0.13-6.1 ml). The mean operative time was 140 min (60-222 min). Stone-free rate (SFR) was 89.3% on KUB, and 82.1% on CT. Three patients (10.7%) had postoperative fever greater than 38.5°C. There were no complications of grade III or higher according to the modified Clavien-Dindo classification. In the Ellenbogen classification, improvement was observed in hydronephrosis of Grade II or lower. Improvement was also observed in cases with Grade III hydronephrosis. However, due to the presence of residual renal atrophy, there was no change in the classification. The preoperative eGFR was 63 ml/min/1.73 m² (36-101 ml/min/1.73 m²) and the postoperative eGFR was not improved. We conclude that ureteral access sheath-assisted percutaneous antegrade ureteroscopic lithotripsy is effective for treating impacted ureteral calculus.