Proof of concept: Exposing the myth of urethral atrophy after artificial urinary sphincter via assessment of circumferential recovery after capsulotomy and intraoperative pressure profiling of the pressure regulating balloon

Amy Marcia Pearlman,Alison Marie Rasper,Ryan Patrick Terlecki 대한비뇨의학회 2018 Investigative and Clinical Urology Vol.59 No.4

Purpose: Rate of continence after artificial urinary sphincter (AUS) placement appears to decline with time. After appropriate workup to exclude inadvertent device deactivation, development of urge or overflow incontinence, and fluid loss, many assume recurrent stress urinary incontinence (rSUI) to be secondary to nonmechanical failure, asserting urethral atrophy as the etiology. We aimed to characterize the extent of circumferential urethral recovery following capsulotomy and that of pressure regulating balloon (PRB) material fatigue in men undergoing AUS revision for rSUI. Materials and Methods: Retrospective review of a single surgeon database was performed. Cases of AUS removal/replacement for rSUI involving ventral subcuff capsulotomy and intraoperative PRB pressure profile assessments were identified. Results: The described operative approach involving capsulotomy was applied in 7 patients from November 2015 to September 2017. Mean patient age was 75 years. Mean time between AUS placement and revision was 103 months. Urethral circumference increased in all patients after capsulotomy (mean increase 1.1 cm; range 0.5–2.5 cm). Cuff size increased, remained the same, and decreased in 2, 3, and 2 patients, respectively. Six of 7 patients underwent PRB interrogation. Four of these 6 PRBs (66.7%) demonstrated pressures in a category below the reported range of the original manufacturer rating. Conclusions: Despite visual appearance to suggest urethral atrophy, subcuff capsulotomy results in increased urethral circumference in all patients. Furthermore, intraoperative PRB profiling demonstrates material fatigue. Future multicenter efforts are warranted to determine if capsulotomy, with or without PRB replacement, may simplify surgical management of rSUI with reductions in cost and/or morbidity.

Safety and feasibility of platelet rich fibrin matrix injections for treatment of common urologic conditions

Ethan L Matz,Amy M Pearlman,Ryan P Terlecki 대한비뇨의학회 2018 Investigative and Clinical Urology Vol.59 No.1

Purpose: Autologous platelet rich plasma (PRP) is used increasingly in a variety of settings. PRP injections have been used for decades to improve angiogenesis and wound healing. They have also been offered commercially in urology with little to no data on safety or efficacy. PRP could theoretically improve multiple urologic conditions, such as erectile dysfunction (ED), Peyronie's disease (PD), and stress urinary incontinence (SUI). A concern with PRP, however, is early washout, a situation potentially avoided by conversion to platelet rich fibrin matrix (PRFM). Before clinical trials can be performed, safety analysis is desirable. We reviewed an initial series of patients receiving PRFM for urologic pathology to assess safety and feasibility. Materials and Methods: Data were reviewed for patients treated with PRFM at our center from November 2012 to July 2017. Patients were observed immediately post-injection and at follow-up for complications and tolerability. Where applicable, International Index of Erectile Function (IIEF-5) scores were reviewed before and after injections for ED and/or PD. Pad use data was collected pre/post injection for SUI. Results: Seventeen patients were identified, with a mean receipt of 2.1 injections per patient. Post-procedural minor adverse events were seen in 3 men, consisting of mild pain at injection site and mild penile bruising. No patients experienced complications at follow-up. No decline was observed in men completing pre/post IIEF-5 evaluations. Conclusions: PRFM appears to be a safe and feasible treatment modality in patients with urologic disease. Further placebo-controlled trials are warranted.

The authors reply: Safety and feasibility of platelet rich fibrin matrix injections for treatment of common urologic conditions

Ethan L Matz,Amy M Pearlman,Ryan P Terlecki 대한비뇨의학회 2018 Investigative and Clinical Urology Vol.59 No.4

Infection following penile prosthesis placement at an academic training center remains low despite involvement of surgeons-in-training

Kara E. McAbee,Amy M Pearlman,Ryan P Terlecki 대한비뇨의학회 2018 Investigative and Clinical Urology Vol.59 No.5

Purpose: Primary care providers harbor misconceptions regarding penile prosthetic surgery, largely overestimating the rate of infection. Rates of infection following surgery for primary placement and revision are estimated as 1% to 3% and 10% to 18%, respectively. Our objective was to determine the contemporary incidence of infection following inflatable penile prostheses surgery at an academic training center where surgeons-in-training are routinely involved. Materials and Methods: Review of a prospectively collected single-surgeon database was performed. All cases of inflatable penile prostheses placement from January 2011 through June 2017 were reviewed. Information regarding training level of assistant surgeon(s) was collected, and follow-up data was compiled regarding postoperative infections and need for revision surgery. Results: Three hundred nine cases meeting inclusion criteria were identified. Mean patient age was 64.2 years, and mean follow-up was 28.7 months. Distribution involved 257 (83.2%) for primary placement, 45 (14.6%) for removal/replacement, and 7 (2.3%) in setting of prior device removal. Diabetes was noted in 31.1% of men. Surgeon-in-training involvement was noted in 100% of cases. Infection was confirmed in a patient who had skin breakdown over an area of corporal reconstruction with polytetrafluoroethylene. The overall postoperative infection rate was 0.3%. Conclusions: In this series from an academic training center, infection following penile prosthetic surgery is low, similar to other centers of excellence, even with 100% involvement of surgeons-in-training. This data should be used to better inform primary care providers and members of the general public potentially interested in restoration of sexual function.

An evaluation of the Manufacturer And User Facility Device Experience database that inspired the United States Food and Drug Administration's Reclassification of transvaginal mesh

Jason M. Sandberg,Ian Gray,Amy Pearlman,Ryan P. Terlecki 대한비뇨의학회 2018 Investigative and Clinical Urology Vol.59 No.3

Purpose: To assess the utility of the Manufacturer And User Facility Device Experience (MAUDE) database in objectively capturing adverse events for transvaginal mesh in the United States. Materials and Methods: We reviewed 1,103 individual medical device reports submitted to the MAUDE database that inspired the United States (US) Food and Drug Administration's 2008 Public Health Notification. Entries were compiled into a categorical database that reported manufacturer, brand, reporter type, report source, and type of adverse event. Results: There were numerous examples of missing, duplicated, and non-standardized entries. Analysis revealed 64 reports with duplicated information, and six reports representing multiple patients. Forty-seven percent of medical device reports did not identify a reporter source. At least 28% of reported devices are no longer on the US market. There was wide variability in the quality and completeness of submitted reports and true adverse event rates could not be accurately calculated because the number of total cases was unknown. Conclusions: The MAUDE database was limited in its ability to collect, quantify, and standardize real-life adverse events related to transvaginal mesh. While it functions to collect information related to isolated adverse events, systematic limitations of the MAUDE database, that no doubt extend to other medical devices, necessitate the development of new reporting systems. Alternatives are under development, which may allow regulators to more accurately scrutinize the safety profiles of specific medical devices.

A Training Algorithm for the Transform Trellis Code with Applications to Stationary Gaussian Sources and Speech

김동윤,박용서,황금찬,Kim, Dong-Youn,Park, Yong-Seo,Whang, Keum-Chan,Pearlman, William A. The Acoustical Society of Korea 1992 韓國音響學會誌 Vol.11 No.1

변환 격차 코드는 모든 레이트에서 정상 가우시안 소오스와 자승 오차 왜곡에 대해 최적코드이다. 본 논문은 실제 데이타의 통계적 특성에 잘 맞는 코드를 얻기 위해 점근적으로 최적인 변환 격자 코드를 훈련시켰다. 훈련 알고리즘은 격자 코드북을 탐색하기위한 M알고리즘과 코드북을 새롭게하기 위한 LBG 알고리즘을 사용했다. 훈련된 변환 격자 코드의 성능을 조사하기 위해서 상관 계수가 0.9인 1차 AR 가우시안 소오스와 실제 음성 데이타를 사용하였다. 1차 AR 소오스에서, 훈련에 사용되지 않은 데이타에 대한 SNR은 레이트에 따라 샤논의 정보량 왜곡 함수에 의한 SNR보다 0.6에서 1.4dB 낮았으나, 이것은 같은 계산량을 사용한 다른 코딩 결과들보다 우수 했다. 실제 음성 데이타는 레이트 1.0 bits/sample에서 코딩을 했으며, 보다 좋은 성능을 얻기 위해 윈도우 함수와 이득 적용을 사용했다. There exists a transform trellis code that is optimal for stationary Gaussian sources and the squared-error distortion measure at all rates. In this paper, we train an asymptotically optimal version of such a code to obtain one which is matched better to the statistics of real world data. The training algorithm uses the M algorithm to search the trellis codebook and the LBG algorithm to update the trellis codebook. We investigate the trained transform trellis coding scheme for the first-order AR(autoregressive) Gaussian source whose correlation coefficient is 0.9 and actual speech sentences. For the first-order AR source, the achieved SNR for the test sequence is from 0.6 to 1.4 dB less than the maximum achievable SNR as given by Shannon's rate-distortion function for this source, depending on the rate and surpasses all previous known results for this source. For actual speech data, to achieve improved performance, we use window functions and gain adaptation at rate 1.0 bits/sample.