Data collection and Follow up
All the patients’ data were obtained from the hospital’s electronic
medical record system. The characteristics of the patients which include
the age, gender, body mass index(BMI), stone burden, history of previous
surgery on the ipsilateral side, urine cultures, whether or not using
antibiotics and comorbidities. The operation time, postoperative
hospital stay, one-time success rate of lithotripsy, renal function and
hemoglobin changes before and after operation were recorded. In
addition, the postoperative complications were also recorded according
to the modified Clavien-Dindo classification as recommended. KUB
examination was performed in all cases on the first day after operation.
All patients were follow up routinely in the outpatient clinic at 1 to 3
month postoperatively. At 1 month postoperatively, non-contrast CT and
urinary ultrasound were performed to confirm the stone clearance status,
in which stone-free rate (SFR) was defined as radiological residual
fragments less than 4mm, and the double J stent was removed in the
outpatient clinic. If the residual stone fragments were more than 4mm,
the removal of double J stent would be delayed until 3 months.