Motion of the kidney between preoperative and intraoperative positioning.

For many laparoscopic surgical procedures, the preoperative images are taken with the patient in a different position than that in which the surgery is performed. The organ shift between positions can affect surgical image guidance, as the organ shifts can complicate image registration. In particular, for partial nephrectomy, the standard clinical approach requires supine preoperative computed tomography, while the surgery is performed in the flank position. We studied ten subjects in both supine and flank positions. Rigid registration was used to determine the relative motion of the kidneys, using the spine as a pose-independent landmark. Our results showed that the kidney can move as much as 46.5 mm as a result of a supine-to-flank change in patient position, and rotate as much as 25°. From the results, significant kidney motion occurs due to the change of patient position from supine to flank. These changes warrant further study to understand and model the patient specific motion.

Penile carcinoma: lessons learned from vulvar carcinoma.

PURPOSE: Penile carcinoma is rare in the developed world and treatment guidelines are often based on marginal clinical data. Prospective controlled studies are virtually absent and meta-analyses are rare. Vulvar carcinoma, on the other hand, has many parallels to penile carcinoma, and the level of evidence for diagnosis and treatment is more robust. Therefore, we assessed the body of literature on vulvar carcinoma to identify potential improvements in the care of patients with penile carcinoma. MATERIALS AND METHODS: A literature review was performed on vulvar carcinoma and direct comparisons were made to a similar review of the literature on penile carcinoma. RESULTS: Several aspects of vulvar carcinoma management are clearly established and deserve closer evaluation in penile carcinoma. For example, human papillomavirus is identified in a high percentage of patients with vulvar carcinoma but is understudied in penile carcinoma. Further study is of potential clinical value, especially with the development of human papillomavirus vaccines for prevention. Penile carcinoma TNM staging does not adequately stratify survival or risk of advanced disease. Staging of vulvar carcinoma is dependent on tumor size and depth of invasion measured in millimeters, as opposed to the invasion of underlying structures in penile carcinoma. Management of the inguinal nodes is more refined for vulvar carcinoma, where lymphatic mapping has been conducted and sentinel node biopsy has proven to be highly effective in multicenter trials. Finally, the efficacy of adjuvant radiation and chemotherapy has been tested in controlled trials or reported in meta-analyses for vulvar carcinoma, which are both lacking for penile carcinoma. Radiation after inguinal node dissection, for example, has been shown to enhance survival in patients with defined risk factors. Neoadjuvant chemoradiation is recommended before surgery for advanced vulvar carcinoma. CONCLUSIONS: Evidence derived from studies on vulvar carcinoma can be extrapolated to penile carcinoma to help guide clinical trials and future research directions to enhance the treatment of these patients.

Prediction of the outcome of antenatally diagnosed hydronephrosis: a multivariable analysis.

PURPOSE: The majority of cases of antenatal hydronephrosis (ANH) resolve postnatally. The purpose of this study was to determine independent predictors for resolution of ANH using a multivariable analysis model. METHODS: A retrospective study was performed on 100 children (80 males and 20 females, 118 renal units) referred to a single pediatric urology clinic with the diagnosis of ANH. Patients with ultimately resolved ANH were compared to unresolved cases in a univariate analysis in terms of sex, laterality, severity of ANH using Society for Fetal Urology (SFU) grading, antero-posterior pelvic diameter (APD), parenchymal thickness, renographic differential function and development of clinical complications, followed by a Cox proportional hazard model for multivariable analysis. RESULTS: Median follow up was 34 months (range 3-204). Hydronephrosis in 62 units resolved spontaneously and pyeloplasty was done in 29. The remaining 27 units had persistent uncomplicated hydronephrosis at last follow up. Multivariate analysis showed larger APD (hazard ratio 0.54; 95%CI 0.36-0.80) and SFU grade 4 (HR 0.34; 95%CI 0.13-0.90) to be associated with a significantly lower likelihood of resolution. The mean initial APD in resolved cases was 9.4mm as opposed to 29.0mm in cases requiring surgery. CONCLUSION: Large initial APD has predictive value for surgical intervention. This model is helpful in counseling families about the potential outcomes of ANH.

Exercise improves bladder function in diabetic mice.

AIMS: We determined the effect of exercise on bladder dysfunction and voiding frequency in db/db mice. MATERIALS AND METHODS: Diabetic db/db female mice (BKS.Cg-Dock7m +/+ Leprdb/J strain) and their age-matched wild-type controls (WT) were equally divided into sedentary and exercise groups. Mice were exercised for 1 hr everyday for 8 weeks (speed of 5.2 m/min). We performed a voiding pattern test, cystometric analysis and reactivity of isolated bladder strips in WT and db/db mice, both sedentary and exercised. RESULTS: Diabetes increased the frequency of voiding, bladder capacity, and residual volume. Exercise decreased voiding frequency in db/db mice; voiding frequency was 5.8 ± 0.5 (db/db exercise) versus 10.8 ± 1.1 (db/db control, P < 0.001). In cystometric analysis, the bladder capacity of db/db sedentary mice was 0.27 ± 0.05 ml and was 0.14 ± 0.02 ml in the db/db exercise group (P < 0.05), whereas the residual volume was 0.2 ± 0.03 ml in db/db sedentary mice and 0.06 ± 0.02 ml in db/db Ex mice. Isolated strips of bladder muscle from sedentary db/db mice were more responsive to carbachol than strips from db/db exercise mice. Exercise did not improve the urodynamic properties of WT mice, both sedentary and exercised. CONCLUSIONS: Exercise improves bladder function in diabetic mice by reducing voiding frequency and improving urodynamic parameters.

Atrophic upper pole of a duplex collecting system masquerading as suprarenal mass: a case study and literature review.

The growing use of maternal fetal ultrasound is leading to the discovery of an increasing number of suprarenal masses. Our experience with a cystic suprarenal mass detected on antenatal ultrasound is described. Location and radiographic features could not rule out the possibility of a cystic neuroblastoma; therefore, surgical resection of the mass was performed. Despite the absence of common radiologic characteristics, the pathology of the specimen revealed a non-functioning upper pole of a duplex kidney with complete duplication of the collecting system. Neonatal evaluation and management and the differential diagnosis are discussed.