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Substantial international cooperation will be required to meet the challenges of the 2015 Paris Agreement on Climate change and UN 2030 Sustainability Goals. International standards can be an important tool for providing structure and guidance in rapidly evolving energy efficiency (EE) and renewable energy (RE) markets, thus improving their positive effect on global climate and energy access goals. This paper presents the key findings and detailed analysis from a 2014 survey of 378 standards developers and policy makers in 37 countries conducted by the International Organization for Standardization's (ISO) Strategic Advisory Group on Energy Efficiency and Renewable Energy Sources. This survey represents the first large effort by ISO to systematically seek external input in mapping policy and standardization needs in EE and RE markets. The survey identified eight key findings, most notably a disconnect between policy makers and standards developers as a potential barrier to developing effective and relevant standards. Specific steps are described to support greater engagement of policy makers during the early stages of standards development and improve standard making outcomes. Greater dialogue and better coordination is needed among standards, as well as between standards and related policies in order to achieve this potential and to make positive contributions to the broader goals of policy cohesion.

Introduction. Sonoelastography is an emerging ultrasound-based technique that allows characterization of tissue stiffness. Aim. The aim of this report is to present a case of significant penile curvature with a non-palpable, non- sonographically visualized plaque that was demonstrable with sonoelastography. Methods. A 60-year-old male presented with significant left penile curvature during erections. The penis was evaluated with physical exam followed by B-mode and color Doppler ultrasound. No evidence of plaque was identified with these modalities. Shear wave sonoelastography was pursued to further characterize the patient's Peyronie's disease. Results. An area of increased tissue stiffness that correlated with the site of maximum curvature was identified with shear wave sonoelastography and used to target intralesional injection therapy. Conclusion. Sonoelastography provides an additional way to characterize, localize, and deliver therapy to a lesion in patients with Peyronie's disease and is particularly useful when palpation and B-mode ultrasonography have failed to demonstrate a plaque. Richards G, Goldenberg E, Pek H, and Gilbert BR. Penile sonoelastography for the localization of a non-palpable, non-sonographically visualized lesion in a patient with penile curvature from Peyronie's disease. J Sex Med 2014;11:516-520.

The transrectal ultrasound (TRUS) study of the prostate enhances patient care by providing a minimally invasive procedure that gives real-time information for a rapid and accurate diagnosis. This chapter includes discussions of the prostate anatomy and embryologic development, the indications for the TRUS, the performance of the study, and TRUS-guided biopsy and disease processes for which the study is used. The intent of the chapter is to assist the urologist in maintaining a high degree of proficiency in performing, interpreting, and documenting the transrectal ultrasound study and biopsy of the prostate.

Low dose computerized tomography protocols have demonstrated a reduction in radiation exposure while maintaining excellent sensitivity and specificity in the detection of stones in patients of average size. Low dose computerized tomography protocols have not yet been evaluated in subjects in the extremes of weight. We evaluated the effect of body weight when using low dose protocols to detect ureteral calculi.Three cadavers of increasing weight (55, 85 and 115 kg) were prepared by inserting 721 calcium oxalate stones (range 3 to 7 mm) in 33 random configurations into urinary tracts. Cadavers were then scanned using a GE LightSpeed® at 7 radiation settings. An independent, blinded review by a radiologist was conducted to generate ROC curves, with areas under the curve compared using a 1-way ANOVA (α = 0.05).Sensitivity and specificity were significantly lower in the low and high weight cadavers compared to the medium weight cadaver at 5 mAs (p0.001) and 7.5 mAs (p = 0.048). Differences in sensitivity and specificity at radiation settings of 15 mAs or greater were not significant.The sensitivity and specificity for the detection of ureteral calculi on computerized tomography were decreased for underweight and overweight subjects when using extremely low dose radiation settings (less than 1 mSv). Low dose protocols of 15 mAs (2 mSv) can still be used for these subjects without jeopardizing the ability to identify ureteral stones.

The male external genitalia include features (both normal and abnormal) that are direct consequences of the development of their embryologic precursors and demonstrable with ultrasound imaging. The testis and adnexa develop in close association with the kidney and ureter in the urogenital ridge. Portions of the early embryonic excretory system develop into the male reproductive ducts. Remnants of the Mullerian ducts may be encountered on the ultrasound examination of the male reproductive structures. The testes descend from the retroperitoneum to their final location in the scrotum. The scrotum develops in close association with the developing phallus. The bladder, prostate, and majority of the urethra are derived from an endodermal structure know as the urogenital sinus, which itself develops from the cloaca. The external phallus and testes have a blood supply that is well demonstrated and evaluated with ultrasound examination. An understanding of the development of the male reproductive structures aides in the interpretation of ultrasound findings during examination of these structures.

The purpose of this study was to evaluate the amount of radiation exposure patients with small renal masses undergoing percutaneous cyroablation (PCA) or percutaneous radiofrequency ablation (PRFA) received during treatment and follow up.A retrospective review was conducted on all patients with small renal masses4 cm treated with PCA or PRFA over a 7-year period in a single academic center. Preoperative, operative, and post-operative variables were collected and compared. Radiation exposure received during treatment and 1 year of follow up were also determined for each modality. Statistical analysis was conducted using SPSS V.17 (SPSS, Chicago, IL). The groups were compared using the Mann-Whitney U and Pearson Chi-Square tests. Statistical significance was considered at p0.05.There was no significant difference in pretreatment parameters or oncologic outcomes. The average PCA treatment radiation exposure was 39.7 mSv (15.5-133.4 mSv) compared with 22.2 mSv (8.1-67.7 mSv) for PRFA (p=0.001). During the initial year after treatment, the estimated mean treatment and follow-up radiation exposure for PCA was 134.5 mSv, compared with 117 mSv for RFA when routine computerized tomography imaging was employed.To our knowledge, this is the first published study that quantifies radiation exposure in PCA and PRFA treatment for small renal masses. These relatively high radiation exposures should be included in the informed consent for these procedures. In addition, caution should be employed when applying these technologies in young patients who are most susceptible to long-term radiation damage.

Background and Purpose: Previous studies using pulsed fluoroscopy have shown variable effects on radiation exposure because of the ramp and trail effect in older C-arm systems. This study compares radiation delivered in pulsed and continuous modalities using a modern C-arm system.Thermoluminescent dosimeters (TLDs) positioned in three body locations directly measured radiation dose during simulated ureteroscopy. Thirty pedal activations were administered using a pulsed or continuous mode to visualize an implanted guidewire and a radiopaque stone. TLD absorbed radiation and image quality were compared between imaging modes.Pulsed fluoroscopy delivered less radiation compared with continuous fluoroscopy at each site: Anterior skin (0.10 vs 0.26 mGy, P0.001), kidney (0.15 vs 0.40 mGy, P0.001), and posterior skin (0.92 vs 2.62 mGy, P0.001). Mean fluoroscopy time differed between continuous and pulsed modes (12.5 vs 3.0 seconds; P0.001). Fluoroscopy time positively correlated with radiation exposure at all sites: Anterior skin (0.017 mGy/s, R(2)=0.90), left kidney (0.026 mGy/s, R(2)=0.96), and posterior skin (0.18 mGy/sec, R(2)=0.98). When evaluated by blinded urologists, 100% of reviewers felt pulsed images were adequate to identify guidewire position and 90.5% felt pulsed images were adequate for stone localization.Pulsed fluoroscopy reduced fluoroscopy time by 76% and radiation dose by 64% compared with continuous fluoroscopy. Pulsed fluoroscopy images were adequate for most tasks of ureteroscopy and should be considered for reduction of radiation during ureteroscopy.

Patients with end stage renal disease plus prostate cancer are ineligible to receive a renal transplant at most centers until an acceptable cancer-free period is demonstrated. To our knowledge previously established prostate specific antigen reference ranges have not been validated in patients with end stage renal disease. We determined age stratified 95th percentile prostate specific antigen reference ranges and the prostate cancer detection rate at specific prostate specific antigen intervals for patients with end stage renal disease.We retrospectively reviewed the records of 775 male patients with end stage renal disease on the waiting list for a renal transplant who had undergone a serum prostate specific antigen test. Prostate specific antigen was stratified by age at the time of the blood test and 95th percentile reference ranges were calculated for each decade. A total of 80 patients underwent prostate biopsy for increased prostate specific antigen and/or abnormal digital rectal examination. The cancer detection rate was calculated for specific prostate specific antigen reference ranges.The age specific 95th percentile prostate specific antigen references ranges were 0 to 4.0 ng/ml for ages 40 to 49 in 137 patients, 0 to 5.3 ng/ml for ages 50 to 59 in 257, 0 to 10.5 ng/ml for ages 60 to 69 in 265 and 0 to 16.6 ng/ml for ages 70 to 79 years in 69. The cancer detection rate was 44%, 38% and 67% for prostate specific antigen 2.5 to 4.0, 4 to 10 and greater than 10 ng/ml, respectively.In our study population of patients with end stage renal disease age stratified prostate specific antigen was higher than in the general population. The cancer detection rate was increased in our patients with end stage renal disease compared to that in patients with normal renal function at specific prostate specific antigen intervals. Lower prostate specific antigen cutoffs may be appropriate to recommend prostate biopsy in patients with end stage renal disease.

Aim: Natural orifice approaches for nephrectomy have included access via the stomach, vagina, bladder, and rectum. The use of the ureter as a natural orifice for natural orifice translumenal endoscopic surgery (NOTES) nephrectomy has not previously been reported. The aim of this study was to test the feasibility of transureteral laparoscopic NOTES nephrectomy. Materials and Methods: Three female farm pigs (29.2–30.8 kg) were placed into the lithotomy position. A cystoscopically placed extra-stiff guide wire was used to place a prototype dilating sheath into the left ureter. After dilation of the ureter and urethra, the sheath was exchanged for a 12-mm bariatric laparoscopic trocar. A 10.5-inch-long, 10-mm offset operating laparoscope with an internal 5-mm working port was utilized for the nephrectomy. One 2-mm and one 2/3-mm port were placed transabdominally to facilitate in situ morcellation. The kidney was cut into slices using the bipolar device and extracted via the ureteral port using the ho...

INTRODUCTION AND OBJECTIVES: There are multiple modalities to produce and capture fluoroscopic images, including continuous and pulsed modes. Continuous fluoroscopy allows for real-time imaging but could deliver larger radiation doses to the patient. Pulsed fluoroscopy delivers bursts of radiation at set intervals, reducing fluoroscopy times. Despite this reduction in times, studies have shown no difference in effective dose when comparing pulsed fluoroscopy to continuous fluoroscopy due to the “ramp and trail effect”. Newer X-ray tubes can now deliver a more uniform current in a pulsed fashion while reducing unwanted radiation by minimizing this effect. The purpose of this study is to directly compare the amount of radiation delivered under pulsed fluoroscopy against continuous fluoroscopy in a modern C-arm system. METHODS: Thermoluminescent dosimeters (TLDs) were implanted at 3 sites in a female human cadaver to directly measure radiation dose, including the left kidney, posterior skin, and anterior skin. While in the supine position, the cadaver received 30 pedal activations either in the continuous or pulsed mode (1 pulse/sec) using a modern C-arm at 69 kVp and 1.51 mAs to visualize an implanted guide wire and a radio-opaque stone. The amount of radiation absorbed by the TLDs was recorded. Data was analyzed using a paired two-tailed Student’s t-test ( 0.05), Wilcoxon Signed Ranks procedure, and least-squares analysis. RESULTS: Pulsed fluoroscopy delivered lower doses of radiation compared to continuous fluoroscopy at each site examined: anterior skin (0.10 vs 0.26 mGy, p 0.001), kidney (0.15 vs 0.40 mGy, p 0.001), and posterior skin (0.92 vs 2.62 mGy, p 0.001). Mean fluoroscopy time differed significantly between continuous (12.5 s, range 12.2–13.7 s) and pulsed (3.0 s, range 2.9–3.0 s; p 0.001). Fluoroscopy time positively correlated with radiation exposure at all sites: anterior skin (0.017 mGy/sec, R 0.90), left kidney (0.026 mGy/ sec, R 0.96), and posterior skin (0.18 mGy/sec, R 0.98). However, pulsed mode delivered more radiation per second of fluoroscopy time compared to continuous mode overall and at all sites (p 0.001). CONCLUSIONS: When using fluoroscopy, pulsed images significantly reduce radiation exposure compared to continuous fluoroscopy. Using the same pedal activation time, continuous mode resulted in significantly longer fluoroscopy times compared to pulsed mode. These longer fluoroscopy times outweighed the higher dose per second delivered by the pulsed fluoroscopy mode. Thus, pulsed fluoroscopy could be used to minimize radiation exposure to patients whenever appropriate.

Introduction: The altruistic act of kidney donation places the donor at risk for complications with no potential direct benefit. Any significant morbidity in a healthy donor is unacceptabl...

Background and Objectives: Natural-orifice approaches for nephrectomy have included access via the stomach, vagina, bladder, and rectum. Recently, the feasibility of using the ureter as a natural orifice for natural-orifice transluminal endoscopic surgery nephrectomy has been demonstrated in a nonsurvival porcine model. The purpose of this study was to assess the outcomes of transureteral laparoscopic natural-orifice transluminal endoscopic surgery nephrectomy in a survival porcine model. Methods: Three pigs underwent hybrid transureteral natural-orifice transluminal endoscopic surgery nephrectomy. An experimental balloon/dilating sheath was inserted over a wire to dilate the urethra, ureteral orifice, and ureter. Through a bariatric 12-mm laparoscopic port, the ureter was opened medially and the hilar dissection was performed. Next, 2 needlescopic ports were placed transabdominally to facilitate hilar transection. The kidney was morcellated using a bipolar sealing device and extracted via the ureter using the housing of a bariatric stapling device. The ureteral orifice was closed with a laparoscopic suturing device. The bladder was drained by a catheter for 10 to 14 days postoperatively. Pigs were euthanized on postoperative day 21. Results: All surgical procedures were successfully completed, with no intraoperative complications. One pig had an episode of postoperative clot retention that resolved with catheter irrigation. Each pig was healthy and eating a normal diet prior to euthanasia. Conclusions: This study demonstrates the feasibility of a hybrid transureteral approach to nephrectomy in a survival porcine model. This technique avoids the intentional violation of a second organ system and the risk for peritoneal contamination. Improved instrumentation is needed prior to implementation in the human population.