Introduction and Objectives: AUA Best Practice Guidelines for uretero-scopic stone treatment recommend antibiotics coverage for less than 24 hours after the procedure. The purpose of this study was to evaluate if the rate of post-operative urinary tract infection (UTI) differed in patients receiving a single dose of antibiotics pre-operatively compared to those patients who also received post-operative antibiotics. Methods: A retrospective review was performed of consecutive patients at two institutions, University of British Columbia and Massachusetts General Hospital, Harvard. All patients were given a single dose of antibiotics prior to ureteroscopic stone treatment. A subset of patients were also given post-operative antibiotics ranging in time and selection of antibiotic. Patients who displayed symptoms of infection had a urine culture performed for speciation and antibiotic sensitivity. Results: Eighty one patients underwent ureteroscopy for renal calculi. Patients with pre and post operative antibiotics were compared to those receiving only pre-operative antibiotics. Eight (9.9%) patients in total (2 from pre-operative antibiotic and 6 from the pre and post-operative antibiotic group, P=0.219) developed UTI's in the post-operative period. Surgical factors such as ureteral access sheath, bilateral procedures, use of basket or laser was not associated with rates of infection or whether the surgeon prescribed post-operative antibiotics. Risk factors such as pre-operative stenting, nephrostomy tubes, and foley catheters did not differ between groups or predispose patients to post operative infections. Conclusions: Our data suggests that post-operative antibiotics do not decrease infection rates following ureteroscopic stone treatment, even among patients with risk factors for infection. A single pre operative dose is sufficient. Objectives: To determine predictors of Fluoroscopy Time (FT) during Percutaneous Nephrolithotomy (PCNL) and assess the impact of urology PostGraduate Trainees (PGTs) and S.T.O.N.E. Nephrolithometry Score. Methods: A prospective review of patients undergoing PCNL between 2010 and 2013 at a tertiary health care centre was performed. Patients' demographics, stone characteristics, including S.T.O.N.E. Nephrolithometry Score, and operative data were compared among PGTs. Predictors of FT were determined using univariate and multivariate models. Results: A total of 103 PCNLs were assisted by 10 PGTs from PostGraduate Years (PGY) 4 and 5 [37 (35.9%) and 66 (64.1%) cases, respectively)]. Sixty percent of patients were males with a mean age of 55.2±1.5 years and a mean BMI of 26.4±0.5 kg/m2. The mean S.T.O.N.E score was 7.7±0.1, with tubeless PCNL in 53 (51.5%) cases. The mean FT was 120±5 seconds, mean operative time was 102±3.5 minutes and mean length of hospital stay was 4.2±0.34 days. The overall stone-free rate was 72.8%. PGY-5 trainees used significantly less FT than PGY-4 trainees (115±6 vs. 130±7 sec; p=0.04). FT significantly correlated with the number of involved calyces (r= 0.24, p= ...