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Abstract: Introduction and Objective: Recent advances in magnetic resonance (MR) technology have allowed for high-resolution ex vivo spectroscopy on small, intact tissue samples. We examined the capability of 1H magnetic resonance magic angle spinning (MR-MAS) to correctly characterize post–radiofrequency ablation (RFA) renal biopsies from human samples, compared with standard histology and cross-sectional imaging. Methods: A minimum of two, 18G, percutaneous renal biopsies were obtained from ten biopsy-confirmed renal tumors at a mean 26.6 mo (range, 15–48) post-RFA. All patients were considered free of disease by computed tomography criteria. A portion of each sample was immediately frozen at −80°C for spectroscopy and the remainder used for pathological analysis. 1H MR-MAS was performed blinded with a 14.1-tesla field strength. Prior renal biopsies from nonablated tissue were used as positive controls for the spectral analysis. Concordance between, computed tomography, histology, and MR-MAS was analyzed. All spectroscopy was processed with VNMR software. Results: Histological analysis of all ten post-RFA biopsies demonstrated no cancer or viable tissue. All MR-MAS spectral peaks for each biopsy were consistent with necrosis and, more importantly, indicated an absence of small molecule metabolites characteristic of both normal and malignant renal tissue. Both MR-MAS and histology confirmed, in each case, the conventional computed tomography determination of complete ablation. Conclusions: MR spectroscopy can correctly diagnose the molecular absence of disease in post-RFA tissue biopsies. This proof of principle study warrants in vivo evaluation to confirm the clinical correlates of this modality. [Copyright &y& Elsevier]

Abstract: Metal nanoshells are a new class of nanoparticle with highly tunable optical properties. Gold nanoshells (GNS) are particularly suitable for use in the surgical arena as their outer shell is composed of a commonly used reduced inert gold. When activated by near infrared light, GNS can raise surrounding temperatures to levels sufficient for cellular ablation. As such, investigators have established both in vitro and in vivo models to examine the role of GNS as a therapeutic modality for the thermal ablation of solid organ tumors. [Copyright &y& Elsevier]

Objectives: To determine whether testosterone would increase angiogenesis in human foreskin, because of the known effects of testosterone on endothelial cells and vascular endothelial growth factor expression. Surgical management of complex hypospadias in a patient who has undergone multiple procedures is technically very challenging. It is possible that therapy to increase the blood supply to this tissue could be beneficial.Methods: We used a newly developed model of human skin transplantation, in which full-thickness human foreskin is transplanted subcutaneously onto the dorsum of a nude rat. At 10 days after transplantation, tissue was treated with either testosterone gel or vehicle control. After an additional 7 days, the tissue was harvested, embedded in paraffin, stained for factor VIII to assess vascularity, and examined histologically.Results: The testosterone-treated tissue demonstrated increased factor VIII staining (31.14 ± 1.53 vessels per high-power field) compared with the control group (18.25 ± 2.3 vessels per high-power field; P <0.0005). Histologic analysis revealed less collagen in the testosterone-treated group compared with the control group.Conclusions: Treatment of human foreskin with testosterone, in a transplant model, increased vascularity and decreased early fibrosis. Testosterone treatment may improve the surgical management of complex hypospadias repair. [Copyright &y& Elsevier]

Objectives: The contribution of crossing vessels to ureteropelvic junction (UPJ) obstruction is controversial. We performed a pilot study on patients undergoing laparoscopic pyeloplasty in whom an intraoperative Whitaker test was performed before and after repositioning a crossing vessel to determine its effect on collecting system drainage. Methods: From August 2004 to July 2005, 10 patients with UPJ obstruction scheduled to undergo laparoscopic pyeloplasty were prospectively enrolled in this study. Routine laparoscopic access to the renal pelvis was obtained, and a crossing vessel, if present, was identified. Before mobilization of the UPJ or the crossing vessel, an intraoperative Whitaker test was performed using a laparoscopic 22-gauge needle to puncture the renal pelvis and infuse saline at a rate of 10 mL/min. Bladder and renal pelvic pressures were measured simultaneously. After complete mobilization of the UPJ and crossing vessel, if present, the Whitaker test was repeated. Dismembered pyeloplasty was then performed. Results: Of the 10 patients, 6 had crossing vessels and 4 did not. The Whitaker test was successfully performed in all patients. Among those with a crossing vessel, all had a crossing artery, and 67% also had a crossing vein. No significant change was found in the renal pelvic pressure after mobilization of the renal pelvis in patients without crossing vessels. In those with crossing vessels, the mean renal pelvic pressure significantly declined after vessel repositioning (25.6 ± 4.5 cm H2O to 9.5 ± 6.6 cm H2O, P = 0.006). Conclusions: In this pilot study, lower pole crossing vessels directly contributed to UPJ obstruction by causing extrinsic compression. [Copyright &y& Elsevier]

Objective: To characterize the changes in urine composition associated with increasing severity of diabetes, we analyzed urine composition relative to glycated hemoglobin (HbA1c) and treatment strategy in a largely minority population.Methods: Patients treated for kidney stones between 2001 and 2013 at a single tertiary institution and had 24-hour urine collections were included in the study. Patients with type 1 diabetes or taking either thiazide diuretics or alkalinizing agents were excluded. Analysis was performed in IBM SPSS Statistics version 20 using multivariate regression, and Kruskal-Wallis testing was used.Results: Nine hundred fifty-five patients were included in this study-268 (28%) with type 2 diabetes mellitus, of whom 53 (19.8%) used insulin. Patients with diabetes had lower urine pH, calcium, and phosphate when compared with the control group, but no significant differences were found between the diabetes groups. Multivariate analysis found that HbA1c had a positive correlation with citrate (P = .008), creatinine (P = .037), urine volume (P = .044), and a trend toward a positive association with urinary calcium calcium (P = .064). Insulin use did not have a significant relationship with urinary parameters but trended toward an inverse relationship with calcium (P = .051). pH was not a significant predictor of any urine constituent.Conclusion: In an ethnically diverse inner city patient population, patients with diabetes mellitus type 2 who use insulin have no significant differences in urine parameters when compared with those on oral hypoglycemics. Worsening glucose control as measured by HbA1c levels predicts increased urine citrate and volume. [ABSTRACT FROM AUTHOR]

Objectives: Patients can search the Internet for prostate cancer information, and YouTube is a popular Web site that they may consult. We analyzed the prostate cancer videos on YouTube for information content and the presence of bias. Methods: YouTube was searched for videos about prostate-specific antigen (PSA) testing, radiotherapy, and surgery for prostate cancer. The included videos were in English and <10 minutes long. Two physician viewers watched each video and assigned a score for information content (excellent, fair, poor) and bias (for, against, neutral, or balanced). A third viewer arbitrated any discrepancies. The kappa statistic was used to measure interobserver variability, and Pearson''s test was used to assess correlation. Results: A total of 14 PSA videos, 5 radiotherapy videos, and 32 surgery videos were analyzed. The PSA testing videos averaged 1480 ± 2196 views and 146 ± 174 s long and had an average viewer rating of 3.1 ± 2.1 (viewer rating scale 0-5). The surgery videos averaged 2044 ± 3740 views and 172 ± 122 s long and had an average viewer rating of scored 3 ± 2.2. The radiotherapy videos averaged 287 ± 255 views and 97 ± 45 s long and had a score of 1.8 ± 2.5. The information content was fair or poor for 73% of all videos. The bias for surgery, radiotherapy, or PSA testing was present in 69% of videos; 0% of videos were biased against treatment or PSA testing. The interobserver variability was well above than expected by chance alone. Conclusions: The results of our study have shown that although some videos are robust sources of information, given the preponderance of modest and unbalanced information among reviewed videos, YouTube is an inadequate source of prostate cancer information for patients. [Copyright &y& Elsevier]

Objective: To describe our initial experience with single keyhole nephrectomy in a porcine model and in human subjects. Methods: Eight nonsurvival laparoscopic nephrectomies were performed in 4 female farm pigs. In 3 renal units, the laparoscopic nephrectomy was performed via a novel single 25-mm trocar, while the remaining 5 nephrectomies were performed using one 10-mm and two 5-mm adjacent trocars. Articulating laparoscopic graspers, conventional endoshears, clips, and a stapler were used for dissection. Three human subjects underwent a single keyhole umbilical laparoscopic nephrectomy with similar instrumentation. Indications for nephrectomy included chronic infection in a nonfunctioning kidney in 2 patients, and a 4.5-cm enhancing renal mass in the other patient. Results: Single keyhole nephrectomy was successfully completed in all 8 porcine renal units and in all 3 human subjects. The mean operative time for the porcine nephrectomies was 49 minutes (range, 20 to 85), with a mean blood loss of 20 mL (range, 5 to 100). Incision size ranged from 3 to 5 cm. The mean operative time for the human nephrectomy cases was 133 minutes (range, 90 to 160). Estimated blood loss was 30 mL, and the kidneys were extracted through a solitary 2 to 4.5 cm periumbilical incision. There were no perioperative complications, and all 3 patients were discharged on hospital day 2. Conclusions: Keyhole umbilical nephrectomy utilizing articulating laparoscopic instrumentation to facilitate triangulation is feasible. We demonstrate safe and successful completion both in a porcine model and in the 3 human patients. Future studies will need to assess the benefits of single-access surgery in comparison to conventional laparoscopy. [Copyright &y& Elsevier]

Introduction: Recent studies have proposed that nearby fat deposits may have metabolic influence on kidney cancer pathobiology. Both fat quantity and quality may play unique roles in this complex relationship. As such, we investigated whether perinephric fat surface area (PFA), a quantitative measure of fat, or Mayo Adhesive Probability (MAP) score, a qualitative measure, were predictive of malignant pathology or Fuhrman grade in small renal masses.Methods: A total of 317 patients undergoing minimally invasive partial nephrectomy between 2010 and 2016 for renal masses were retrospectively reviewed. Preoperative abdominal CT and MRI scans were measured for PFA and MAP scores. Multiple binary logistic regression models were created to identify predictive factors of malignant disease and Fuhrman grade.Results: A total of 253 patients had malignant masses, while 64 had benign masses. A total of 189 of the malignant masses were T1a, while 64 were designated T1b. A total of 221 patients with malignant masses had reported Fuhrman grades. Of these 211 patients, 143 (64.7%) had low-grade and 78 (35.3%) had high-grade disease. Mean PFA was 18.0 ± 13.3 cm2, while mean MAP score was 2.6 ± 1.2. Binary logistic regression analysis yielded three variables in the best-fit model for predictors of malignant pathology: MAP score (OR = 1.374, 95% CI: 1.007-1.873, P = 0.045), male sex (OR = 2.058, 95% CI: 1.004-4.218, P = 0.049), and BMI (OR = 1.064, 95% CI: 0.998-1.135, P = 0.059). Neither MAP nor PFA was predictive of Fuhrman grade.Conclusions: MAP score, a measure of perinephric fat quality, but not PFA, a qualitative measure of fat quantity, was predictive of malignant pathology, raising the question whether fat quality rather than quantity may be involved in the pathophysiology of RCC in a large and diverse patient population. Understanding the increasing burden of obesity, further studies are needed to elaborate on these findings and to discern the exact relationship between perinephric fat deposits and renal tumorigenesis. [ABSTRACT FROM AUTHOR]