Login to Access Video or Poster Abstract: MP50-06
Sources of Funding: None

Introduction

Ureteral access sheaths (UAS) are commonly used at the time of ureteroscopic lithotripsy (URSL) for the treatment of nephrolithiasis to facilitate multiple scope passages, stone extraction, and improve irrigation flow. There is a potential risk of ureteral injury and stricture formation with UAS use. We sought to review our UAS experience to better define both the risk of and predictors of post-operative hydronephrosis and ureteral strictures. _x000D_ _x000D_

Methods

531 consecutive URSL with UAS (12/14 Fr) at a tertiary care center by a single surgeon were retrospectively reviewed between September 2010 to March 2016. We evaluated patient factors, operative details, and post-operative imaging in patients undergoing URSL with UAS.

Results

Ureteral access sheaths were successfully placed in 506 (95.3%) of patients. Table 1 lists the demographics and stone characteristics of the cohort. The mean aggregate stone size was 15.4 mm. 272 (51.4%) patients had a pre-operative stent. 74 (14%) patients needed additional procedures to clear residual stone burden. 53 (10%) patients had hydronephrosis on post-operative imaging. The hydronephrosis was mild in 39 (73.6%), moderate in 12 (22.6%), and severe in 2 (3.8%) patients. Follow-up demonstrated that hydronephrosis resolved without intervention in 39 (73.6%) of patients. The mean time to resolution of hydronephrosis on imaging was 222 days. An additional 10 (18.9%) of patients had persistent hydronephrosis without evidence of obstruction on functional imaging. Four patients (7.5%) had persistent hydronephrosis and some degree of obstruction on functional imaging. Univariate analysis found that an unsuccessful UAS placement was the only predictor for the development of post-operative hydronephrosis (28% vs 9.1%, p=0.002)

Conclusions

UAS use at the time of URSL was successful in most patients and the risk of long-term obstruction is low. Post-operative hydronephrosis was observed in 10% of patients, however the majority of this hydronephrosis was mild and resolved without intervention.

Funding

None