童綜合醫院 外科部 泌尿科
Ureteral Access Sheath Insertion Failure and Correlation with Prediction Factors in Retrograde Intrarenal Surgery
Retrograde Intrarenal Surgery (RIRS) is becoming a more important role in management of renal stone and upper ureteral stone. Ureteral access sheath (UAS) insertion was commonly performed before the procedure for easy access of flexible ureteroscopes. However, failure in UAS insertion is a frustrating setback, which may postpone or impede the operation. This study is meant to explore possible predictors for UAS insertion failure.
Materials and Methods :
We retrospectively collected urolithiasis patients who underwent RIRS between 2020 and 2021 in a single medical center. 11/13 French (Navigator, Boston Scientific) UAS was used in this study. We measured ureter diameter at L5 vertebral bone level on abdomen contrast computed tomography or intravenous pyelography to evaluate ureter width. Pre-operative parameters (ureter diameter, hydronephrosis, pre-operative WBC) and clinical characteristics (Age, BMI, gender, DM, HTN) were collected and analyzed by independent T test and chi square test under SPSS software.
Data of 212 patients who underwent RIRS were reviewed and analyzed in this study. The failure rate of UAS insertion was 8.4% (18 patients). 42 patients (19.8%) were pre-stented or pre-dilated by balloon ureteral dilator without UAS insertion failure. Statistic tests revealed pre-operative conditions such as age, gender; DM, HTN, ureter diameter and presence of hydronephrosis were not associated with UAS insertion failure.
Our study demonstrated the benefit of pre-stenting before RIRS. None of the pre-stented patients had failure of UAS insertion in our study. Ureter diameter and pre-operative parameters cannot be used to predict the failure of UAS.