Back End Answers To Cofactor
001). In addition, it showed significant positive correlation with operative time (p = 0.001), estimated blood loss (EBL) (p = 0.005), and length of hospital stay (LOS) (p = 0.001).5 However, there was no impact of this scoring system on the incidence of post-PCNL complications (p = 0.09). 5,6 The Guy��s scoring system has been externally validated.7,8 However, the S.T.O.N.E. nephrolithometry scoring system has not been externally validated. Therefore, the objective of this study was to perform Cofactor external validation of S.T.O.N.E. nephrolithometry scoring system for the preoperative assessment of PCNL outcomes. We hypothesize that the S.T.O.N.E. nephrolithometry scoring system will predict operative time, EBL, LOS, and postoperative stone-free status and complications. Methods Study design After obtaining approvals from the Institutional Review Board (No. 14-050-GEN) and the Director Everolimus datasheet of Professional Services of McGill University Health Centre, electronic charts and PCNL datasheets of all patients undergoing PCNL between 2009 and 2013 were retrospectively reviewed. All PCNLs, except one, were performed in the prone position under general anesthesia as described previously.9 At the end of the procedure, antegrade indwelling double-pigtail 6F ureteral stents together with 20F council-tip nephrostomy tubes were inserted. For tubeless cases, the skin was closed with 4-0 absorbable suture. All PCNLs were performed by a single fellowship-trained endourologist (SA), who filled out the PCNL datasheets immediately postoperatively. These PCNL data-sheets contained intra-operative procedural details regarding the number of punctures, number of tracts, operative and fluoroscopy times, in addition to EBL and intra-operative stone-free status. Moreover, the assistance and level of postgraduate trainees were recorded. A puncture was defined as a needle pass to the kidney to obtain percutaneous renal access (PCA). A tract was defined as a successful puncture over which dilatation was performed. Palbociclib order To be congruent with the original study by Okhunov and colleagues, second-look PCNL procedures were excluded, while including the first PCNL procedures for patients who underwent second-look PCNL later on.5 Therefore, the exclusion criteria were second-look PCNLs, and PCNLs where the percutaneous renal access was obtained by interventional radiology. S.T.O.N.E. nephrolithometry scores were calculated using preoperative NCCT scans, according to what has been previously described by Okhunov and colleagues.5,6 The tract length recorded in millimeters represented the distance from the centre of the stone to the skin at an angle of 45�� on preoperative NCCT scans. The S.T.O.N.E. nephrolithometry score was then correlated with stone-free status (stone-free vs. non-stone-free), EBL (
