A porcine bladder model of pre-clinical urodynamics demonstrates increased afferent nerve activity during filling.

INTRODUCTION AND OBJECTIVES: Urodynamics are the accepted gold standard for the evaluation of multiple forms of voiding dysfunction. However, the tests are expensive, invasive, poorly reproducible, and often prone to artifacts. Therefore, there is a pressing need to develop next-generation urodynamics. The purpose of this study was to develop a novel ex vivo porcine bladder urodynamics model with afferent pelvic nerve signaling that can be used as a preclinical surrogate for bladder sensation. METHODS: Porcine bladders including the ureters and vascular supply were harvested from local abattoirs using an established protocol in both male and female animals. Ex vivo bladder perfusion was performed using physiologic MOPS (3-(N-morpholino) propanesulfonic acid) buffer solution. The pelvic nerve adjacent to the bladder was grasped with micro-hook electrodes and electroneurogram (ENG) signals recorded at 20 kHz. Bladders were filled with saline at a nonphysiologic rate (100 mL/min) to a volume of 1 L using standard urodynamics equipment to simultaneously record intravesical pressure. ENG amplitude was calculated as the area under the curve for each minute, and ENG firing rate was calculated as number of spikes (above baseline threshold) per minute. At the conclusion of the experiment, representative nerve samples were removed and processed for nerve histology by a pathologist (hematoxylin and eosin and S100 stains). RESULTS: A total of 10 pig bladders were used, and nerve histology confirmed the presence of nerve in all adequately processed samples. Vesical pressure, ENG firing rate, and ENG amplitude all increased as a function of filling. During filling tertiles (low fill: min 1-3, med fill: min 4-6, and high fill: min 7-10), normalized pressures were 0.22 ± 0.04, 0.38 ± 0.05, and 0.72 ± 0.07 (cmH2O). Similarly, normalized ENG firing rates were 0.08 ± 0.03, 0.31 ± 0.06, and 0.43 ± 0.04 spikes/minute, respectively, and normalized nerve amplitudes were 0.11 ± 0.06, 0.39 ± 0.06, and 0.56 ± 0.14) µV, respectively. Strong relationships between average normalized pressure values and averaged normalized ENG firing rate (r2 = 0.66) and average normalized ENG amplitude (r2 = 0.8) were identified. CONCLUSIONS: The ex vivo perfused porcine bladder can be used as a preclinical model for the development of next-generation urodynamics technologies. Importantly, the model includes a reproducible method to measure afferent nerve activity that directly correlates with intravesical pressure during filling and could potentially be used as a surrogate measure of bladder sensation.

Myoepithelial carcinoma of the bladder: Case report and review of the literature.

Myoepithelial carcinoma is a neoplasm that classically arises in the parotid glands, nasopharynx, paranasal sinus, and nasal cavity of the head and neck. It rarely arises in other organs or soft tissues and involvement of genitourinary organs is distinctly rare. We describe a case of a 21-year-old male, presenting with nausea, weight loss, and worsening suprapubic pain over 3 months, found to have a large mass at the dome of the bladder. Partial cystectomy was ultimately performed revealing myoepithelial carcinoma of the bladder. The patient is free of disease at four years without the need for systemic therapy.

The Surgical Learning Curve for Biochemical Recurrence After Robot-assisted Radical Prostatectomy.

BACKGROUND: Improved cancer control with increasing surgical experience-the learning curve-was demonstrated for open and laparoscopic prostatectomy. In a prior single-center study, we found that this might not be the case for robot-assisted radical prostatectomy (RARP). OBJECTIVE: To investigate the relationship between prior experience of a surgeon and biochemical recurrence (BCR) after RARP. DESIGN, SETTING, AND PARTICIPANTS: We retrospectively analyzed the data of 8101 patients with prostate cancer treated with RARP by 46 surgeons at nine institutions between 2003 and 2021. Surgical experience was coded as the total number of robotic prostatectomies performed by the surgeon before the patient operation. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: We evaluated the relationship of prior surgeon experience with the probability of BCR adjusting for preoperative prostate-specific antigen, pathologic stage, grade, lymph-node involvement, and year of surgery. RESULTS AND LIMITATIONS: Overall, 1047 patients had BCR. The median follow-up for patients without BCR was 33 mo (interquartile range: 14, 61). After adjusting for case mix, the relationship between surgical experience and the risk of BCR after surgery was not statistically significant (p = 0.2). The 5-yr BCR-free survival rates for a patient treated by a surgeon with prior 10, 250, and 1000 procedures performed were, respectively, 82.0%, 82.7%, and 84.8% (absolute difference between 10 and 1000 prior procedures: 1.6% [95% confidence interval: 0.4%, 3.3%). Results were robust to a number of sensitivity analyses. CONCLUSIONS: These findings suggest that, as opposed to open and laparoscopic radical prostatectomy, surgeons performing RARP achieve adequate cancer control in the early phase of their career. Further research should explore why the learning curve for robotic surgery differs from prior findings for open and laparoscopic radical prostatectomy. We hypothesize that surgical education, including simulation training and the adoption of objective performance metrics, is an important mechanism for flattening the learning curve. PATIENT SUMMARY: We investigated the relationship between biochemical recurrence after robot-assisted radical prostatectomy and surgeon's experience. Surgeons at an early stage of their career had similar outcomes to those of more experienced surgeons, and we hypothesized that surgical education in robotics might be an important determinant of such a finding.

Association of rapidly destructive osteoarthritis of the hip with intra-articular steroid injections.

BACKGROUND: To assess the relationship between rapidly destructive osteoarthritis (RDOA) of the hip and intra-articular steroid injections. METHODS: Coding records from 2000 to 2013 were used to identify all subjects who had a fluoroscopy-guided intra-articular hip injection to treat pain associated with primary osteoarthritis. Radiographic measurements from preinjection and postinjection imaging were evaluated with Luquesne's classification of RDOA to determine diagnosis (greater than 50% joint space narrowing or greater than 2 mm of cartilage loss in 1 year with no other forms of destructive arthropathy). Demographic information, health characteristics, and number of injections were collected and analyzed as other potential explanatory variables. Patient outcome assessed by need for total hip arthroplasty (THA) after injection was also recorded. RESULTS: One hundred twenty-nine injection events met the inclusion criteria in a total of 109 patients. From this sample, 23 cases of RDOA were confirmed representing a 21% incidence of RDOA. Twenty-one of the patients (91%) with RDOA had a THA at a median time of 10.2 months (interquartile range: 6.5-11.2) compared with 27 (31%) of those without RDOA at a median time of 24.9 months (interquartile range: 15.3-65.3). Older patients, patients with more severe osteoarthritis, and patients who identified themselves as white were more likely to have a diagnosis of RDOA (P = .008; P = .040; P = .009, respectively). CONCLUSIONS: The potential for RDOA and faster progression to THA raises questions about the use of intra-articular steroid injections for hip osteoarthritis and should be discussed with patients. Additional studies are needed to define a true relationship.