1. SURGEON-PERFORMED ULTRASOUND FOR STENT POSITION IN LAPAROSCOPIC PYELOPLASTY Stephen D Adams, Costa Healy, Sengamalai Manoharan, Stephen Griffin, Henrik Steinbrecher Department of Paediatric Surgery and Urology, Southampton Children’s Hospital, Faculty of Medicine, University of Southampton Introduction It is our current practice to place a JJ ureteric stent antegradely when performing laparoscopic pyeloplasty. Several methods are described for confirming that the distal end of the stent reaches the bladder, including fluoroscopy or methylene blue in the bladder. Both have limitations. We aimed to determine whether surgeon-performed ultrasound scan can reliably confirm that a JJ-stent has reached the bladder. Ultrasound Technique Clear images of the stents could be obtained using the portable trans-abdominal ultrasound vascular probe already in common use in our theatre. The practitioners were given no specific training, however all are familiar with the interpretation of ultrasound images and have a working familiarity with the Sonosite machine. The depth settings were increased as required to a maximum of 6cm, often the probe needed to be rotated 90º to obtain a satisfactory image of the stent within the bladder. Future directions for this type of assessment include the potential to utilise a 5mm laparosopic ultrasound probe, this would have the advantage of incorporating the assessment into the main part of the pyeloplasty. Results Thirteen patients, median age 10 (Range 5-15 years) were included. Eight scans were performed at insertion and 5 at retrieval. In 11 patients (85%) the end of the JJ stent was correctly identified in the bladder (confirmed at cystoscopic retrieval). In the other 2 patients the stents were not identified in the bladder and this was initially attributed to obesity or technical difficulties. However in neither case was the stent to be found in the bladder and both required ureteroscopic removal. Methods Prospective data collection from Dec 2013-Jan 2015. Portable ultrasound (Sonosite TM M-Turbo) was used to evaluate whether the stent was visible in the bladder peri- operatively either at primary operation or prior to stent removal. The sonographic position of the stent was compared to the cystoscopically confirmed position at extraction. Discussion We have found surgeon-performed peri-operative ultrasound to be both sensitive and specific in confirming that the stent has reached the bladder when performing laparoscopic pyeloplasty in children. When the ultrasound did not clearly demonstrate the stent lying within the bladder this proved to be a true negative finding in both cases. This pilot study is clearly limited by small numbers, yet provides encouraging results. We note the current limitation of our scanning device to a depth of 6cm and accept that there may be difficulty obtaining reliable images in the obese patient. Conclusions We recommend surgeon-performed ultrasound as a reliable non-ionising modality to confirm good stent position at laparoscopic pyeloplasty. It appears to be both sensitive and specific for correct positioning. When there is uncertainty about stent position on portable ultrasound, then further investigation such as fluoroscopy is indicated. Sonosite TM was used to evaluate for stent present in the bladder Correct stent positioning was confirmed at cystoscopic removal 2015 Bladder Stent Clinical images are used with consent