The hydrophilic-coated inflatable penile prosthesis: 1-year experience

Current devices, outcomes, and pain management considerations in penile implant surgery: an updated review of the literature

ABSTRACT

Penile prosthesis surgery is a definitive treatment for erectile dysfunction (ED). The two categories of penile prosthesis are endorsed by professional guidelines, inflatable penile prosthesis (IPP) and malleable penile prosthesis (MPP). Each modality of penile prosthesis offers distinct advantages and incorporates specific design features, allowing for personalized device selection that aligns with individual needs and preferences. While the overall complication rate of penile implant surgery remains low, surgeons should maintain a high index of suspicion for complications in the perioperative time period. Multimodal analgesic regimens including nerve blocks and narcotic-free pathways should be administered to manage perioperative pain. Finally, the high patient satisfaction after penile prosthesis surgery underscores the success of this ED treatment option.

Technological advances in penile implants: past, present, future

Attempts to "cure" erectile dysfunction (ED) are as old as recorded history. The history of penile prosthetic devices dates back over 500 years, when a French military surgeon designed the first known wooden prosthesis to support micturition. There have since been a great many technological advancements in penile prosthetics. Penile implants for the improvement of sexual function date to the twentieth century. Like all human endeavors, penile prosthesis innovations have progressed via trial and error. This review aims to provide an overview of penile prostheses for the treatment of ED since their introduction in 1936. More specifically, we aim to highlight important advances in penile prosthesis development and discuss dead ends that were abandoned. Highlights include two-piece inflatables, three-piece inflatables, and malleable/semirigid, along with modifications and updates to each basic design that improved both insertion and usability. Dead ends include innovative ideas that were lost to history due to a variety of factors. We also look to the future and discuss expected advances, including remotely activated devices and prostheses designed for special populations, including transgender men.

Penile implant infection part 3: the changing spectrum of treatment

Penile prosthesis infection remains a rare but devastating complication of implantation. Historically, management of device infection was always extirpation. While certainly effective, device removal leaves an unhappy patient with a shortened penis. In this last part of a three-part series on the topic of penile prosthesis infection, we seek to highlight new and emerging ideas of infection management which have allowed surgeons the option of preserving the implanted status in select patients.

Penile Implants: A Lesson from the First 50 Years

This year marks the fiftieth anniversary of the first implant of an inflatable penile prosthesis (IPP). The authors of this paper want to celebrate the event with a narrative review of the current literature. The main scopes are antibiotic prophylaxis, patient satisfaction, and future developments. The implant of the first IPP in 1973, performed by Branteley Scott was a turning point in the history of penile prosthesis, revolutionizing the treatment of erectile dysfunction (ED). Since then, the idea of an inflatable device has not changed much. However, the innovations in design, materials, surgical techniques, and perioperative management led to a more natural, durable, and reliable device featuring fewer complications and greater patient satisfaction. Currently, IPP is associated with high patient satisfaction and excellent long-term outcomes, remaining the gold standard for men with refractory ED. Several strategies are under investigation to improve the technology of penile prosthesis, and we expect in the next future the introduction of new devices that are easier to activate, discreet, comfortable when deflated, and durable in time, mimicking a more physiological erection.

Formulation of water-soluble Buddleja globosa Hope extracts and characterization of their antimicrobial properties against Pseudomonas aeruginosa

Buddleja globosa Hope (BG) extracts are traditionally used to treat skin and gastric ulcers due to their healing properties. Non-aqueous solvents such as ethanol and DMSO are usually used to extract naturally occurring compounds. However, the cytotoxicity of these solvents and the low water solubility of the extracted compounds can hinder their biomedical applications. To overcome the limited solubility of the BG extracts, we aimed to enhance the solubility by processing a standardized hydroalcoholic extract (BG-126) through spray drying (SD), with and without two solubility enhancers. Spray-dried BG (BG-SD) extracts and spray-dried BG extracts plus polyvinylpyrrolidone (BG-SD PVP) and Soluplus® (BG-SD SP) were developed starting from BG-126 (containing 53% ethanol). These four formulations were characterized by total phenolic content, water solubility at 25°C and 37°C, and antimicrobial properties against Pseudomonas aeruginosa. All the SD formulations presented a solubility that allowed them to reach maximum concentrations of 1,024 μg/ml catechin for BG-SD and 2,048 μg/ml catechin for BG-SD PVP and BG-SD SP for antimicrobial testing. BG-SD showed the highest antimicrobial potency with a minimum inhibitory concentration (MIC) of 512 μg/ml catechin, followed by BG-126 with a MIC of 1,024 μg/ml catechin and SP. BG-126 was also shown to inhibit biofilm formation, as well as the excipients PVP and SP. The spray-dried BG (BG-SD) extract represents a promising natural active component with enhanced antimicrobial properties against P. aeruginosa for further research and the development of novel phytopharmaceuticals.

Safety and Efficacy of Inflatable Penile Prostheses for the Treatment of Erectile Dysfunction: Evidence to Date

Erectile dysfunction (ED) is a common problem, and prevalence rates are expected to rise as life expectancy increases worldwide. In more severe cases of ED, penile prosthesis implantation has been an excellent option for patients. Over the past few decades, significant design improvements have been made to the penile prosthesis and modifications to surgical technique to improve clinical outcomes. The purpose of this review is to summarize the safety and efficacy of FDA-approved penile implants in the US market. Design modifications have greatly improved the safety and reliability of the implant. Development of improved surgical techniques has decreased intraoperative injuries and reservoir-related complications. With its high overall satisfaction rates and low risk of complications, the inflatable penile prosthesis remains an excellent option for patients with erectile dysfunction.

Narrative review of penile prosthetic implant technology and surgical results, including transgender patients

Over the past 40 years, the technological and surgical advancements in penile prostheses have led to increased patient satisfaction rates and decreased complication and infection rates. In cis males with erectile dysfunction (ED), these technological improvements tremendously improve quality of life. In female to male transgender patients, prostheses provide the ability to engage in penetrative intercourse and to urinate standing. This review evaluates technological and surgical advancements in penile prosthetics in the context of documented patient satisfaction and complication rates from prosthesis surgeries. Retrospective studies of penile implant usage in female to male gender-affirming surgeries report that infection and complication rates are higher than those seen in cis males. There are newer prostheses developed specifically for female to male reassignment surgeries, but outcome data is limited. Continued research and development are needed to develop more efficacious penile implantation options for gender affirmation surgery.

A systematic review of penile prosthesis infection and meta-analysis of diabetes mellitus role

Background

Infection is the most feared complication of a penile prosthesis. Diabetes mellitus (DM) is widely known to increase the risk of several infections, but its role in the penile prosthesis is still controversial. This systematic review aims to show the contemporary scenario of penile prosthesis infection and present a meta-analysis about DM contribution to penile prosthesis infection.

Methods

The review was performed with no language or time limitation, including ten databases. The included articles were about the male population who received a penile prosthesis with no model restriction, with a minimum follow up of 1 year, and outcomes adequately reported.

Results

The mean infection incidence of penile prosthesis ranged from 0.33 to 11.4%. In early 2000, the general incidence of infection was 3 to 5%, then, the introduction of coated materials decreased it to 0.3 to 2.7%. The meta-analysis showed that diabetes mellitus is related to an increased risk of penile prosthesis infection with an odds ratio of 1.53 (95% CI 1.15–2.04).

Conclusions

Penile prosthesis infection decreased in the last decades but remains a significant cause of reoperation, and it is related to lower prosthesis survival. Meta-analysis concludes that diabetes mellitus is related to a higher risk of penile prosthesis infection.

Revision Surgery for Inflatable Penile Prosthesis (IPP): A Single-Center Experience and Pictorial Representation

OBJECTIVE

To elucidate factors influencing Inflatable Penile Prosthesis (IPP) revision and describe outcomes associated with revision surgery.

METHODS

A single surgeon, retrospective review of all patients who underwent IPP revision between 2008-2016, was performed. Patient age, BMI, operative duration, blood loss, hospital duration, time from most recent penile implant to revision surgery, etiology of revision, and whether the patient had a prior failed revision surgery were all collected and analyzed.

RESULTS

A total of 57 patients, who had undergone IPP revision between the years 2008-2016, with at least 3 years of follow-up, were included in the investigation. Mean patient age and BMI were 68 and 29.2 kg/m², respectively. The mean time between the most recent implant operation to revision was 8.4 years. Four patients (7%) reported IPP revision failure within a 3-year follow-up period.

CONCLUSION

IPP revision demonstrates a relatively high success rate, in the short term, and should be offered to patients as a safe and effective option.

Infected penile prosthesis: literature review highlighting the status quo of prevention and management

INTRODUCTION

Erectile dysfunction affects over 50% of men 70 years and above, and penile prosthesis (PP) is its third-line treatment. Complications of PPs include infection, however, no formal guidelines exist for its management.

METHODS

We performed a literature search and reviewed 53 recent published literatures of experiences with management of PP infections, prevention, and treatment.

RESULTS

Acute infection can present early with pain and discharge and detection of early signs is of utmost importance. MRI studies are more sensitive than CT studies to diagnose and plan surgical intervention. Introduction of antibiotic impregnated devices attributed to the reduction of infection rates with superiority proven for certain types; the no-touch technique had further reduced this rate. The Mulcahy salvage remains the most widely used surgical approach for treatment despite modifications and novel techniques described; conservative management of PP infections is recently reported with promising results.

CONCLUSIONS

Despite absence of strict guidelines for the management of infected PPs, we reviewed and discussed numerous panel opinions and suggestions throughout literature. More research into the pathology, prevention, conservative management and advances in surgical treatment of this condition are called for to produce guidelines that unite the efforts to tackle these infections.

UK practice for penile prosthesis surgery: baseline analysis of the British Association of Urological Surgeons (BAUS) Penile Prosthesis Audit

OBJECTIVES

To undertake a prospective multicentre national audit of penile prosthesis practice in the UK over a 3-year period.

PATIENTS AND METHODS

Data were submitted by urological surgeons as part of the British Association of Urological Surgeons Penile Prosthesis National Audit. Patients receiving a penile prosthesis (inflatable or malleable) were included as part of a prospective registry over a 3-year period. Data were validated and then analysed using a software package (Tableau).

RESULTS

A total of 1071 penile prosthesis procedures were included from 22 centres. The three commonest aetiological factors for erectile dysfunction were diabetes, prostate surgery and Peyronie's disease. Of the recorded data, inflatable penile prostheses were the commonest devices implanted, with 665 devices used (62.1%), whereas malleable prostheses accounted for 14.2% of the implants. Recorded intra-operative complications included urethral injury (0.7%, n = 7), corporal perforation (1.1%, n = 12) and cross-over (0.6%, n = 6). Known postoperative complications were recorded in 9.8% of patients (74/752), with the two most frequently reported being postoperative penile pain (n = 11) and scrotal haematoma (n = 14).

CONCLUSION

This baseline analysis is the largest prospective registry of penile prostheses procedures to date. The data show that, over the 3-year collection period in the UK, there are now fewer surgeons performing the procedure, together with a reduction in the number of centres. Peri-operative complications were infrequent, and the rate of implant abortion (e.g. as a result of urethral injury) was very low. Further follow-up data will be required to publish long-term outcomes and patient satisfaction.

Minimizing Penile Prosthesis Implant Infection: What Can We Learn From Orthopedic Surgery?

The implantation of penile protheses for the surgical treatment of erectile dysfunction has risen in popularity over the past several decades. Considerable advances have been made in surgical protocol and device design, specifically targeting infection prevention. Despite these efforts, device infection remains a critical problem, which causes significant physical and emotional burden to the patient. The aim of this review is to broaden the discussion of best practices by not only examining practices in urology, but additionally delving into the field of orthopedic surgery to identify techniques and approaches that may be applied to penile prothesis surgery.

Penile implant infection prevention part 1: what is fact and what is fiction? Wilson's Workshop #9

Inflatable penile prosthesis (IPP) infections are undeniably devastating for patient and surgeon alike. While less common in this modern era, the landscape of prosthesis infection is shifting. Continued examination of risk factors for infection and re-evaluation of common practices remain critical should we aim to advance the field. Quality research on this topic is limited by several factors, among which small sample size and lack of coordinated effort pose the most precarious of challenges. Nonetheless, careful analysis of available data in conjuncture with judicious utilization of established research from other prosthetic fields can help us better grasp the issue at hand. In this review, we aim to do exactly that-to examine available evidence in an effort to discern fact from fiction. In this first part of the three part series, we aim to summarize our understanding of the pathogenesis behind prosthesis infections, explore known preoperative risk factors, and discuss intraoperative considerations for infection prevention. In the second part of this series, we will examine the game changing effect of infection retardant implant coatings. Part three of the series details postoperative prevention strategies, reviews salvage techniques, and discusses additional key considerations.

Intraoperative Use of Betadine Irrigation is Associated With a 9-Fold Increased Likelihood of Penile Prosthesis Infection: Results From a Retrospective Case-Control Study

Introduction

Infection remains a persistent complication of penile prosthesis (PP) surgery. Despite popularity of Mulcahy’s PP washout protocol, Betadine has known tissue toxicity.

Aim

We evaluated PP infection rate based on the type of intraoperative irrigation used, ½ strength Betadine vs vancomycin/gentamicin.

Methods

We reviewed a prospective database of men undergoing primary, revision, and salvage PPs. No other changes to operative or perioperative techniques occurred after the change in irrigation solution. Univariate and logistic regression analyses were used to evaluate differences in infection rate with use of Betadine vs vancomycin/gentamicin irrigation. Potential confounders were reviewed.

Main Outcome Measure

The primary outcome was rate of PP infection before and after change of intraoperative irrigation.

Results

From 2014 to 2018, 217 patients underwent PP placement at our institution by a single surgeon; of whom, 21 (9.7%) experienced an infection (primary = 10 [7.1%], revision = 11 [17.19%], salvage = 0 [0%]). Overall, 152 (70%) received irrigation with Betadine and 65 (30%) with Vancomycin/Gentamicin. Univariate analysis demonstrated significantly increased infection rates with Betadine irrigation (odds ratio [OR]: 4.64, P = .006) and with revision surgery (OR: 2.68, P = .02). Significance of increased infection rate with Betadine was maintained (OR: 9.3; P = .025) after controlling for age, body mass index, Charlson comorbidity index, smoking, diabetes, primary vs revision/salvage, prior penile surgery, use of ectopic reservoir, and adjunctive glanulopexy.

Conclusions

Changing from intraoperative Betadine to vancomycin/gentamicin solution dramatically reduced infection rates among men undergoing PP placement in both primary and revision cases. We hypothesize that differences in infection rate may relate to the relative toxicity or non-sterile nature of Betadine.

Manka MG, Yang D, Andrews J, et al. Intraoperative Use of Betadine Irrigation is Associated With a 9-Fold Increased Likelihood of Penile Prosthesis Infection: Results From a Retrospective Case-Control Study. Sex Med 2020;8:422–427.

Organization of the operating room and specific instruments for the implant of penile prosthesis

After more than 1600 penile implant surgeries, we can affirm the need for a procedure protocol of the steps prior to this type of surgery, and the importance of carefully control the preparation for the surgical act. The instruments that must be available for surgery include elements that have been specifically designed for this type of intervention, such as the Cavernotomo dilators (Rossello®) or the Furlow. These are essential for penile implant surgeries in the usual practice, especially in complex cases or when complications arise. We should avoid complications as much as we can, or at least we should be able to minimize, address and resolve them with effective organization and adequate instruments. Undoubtedly, the surgeon's skills and experience are one of the key components for success, but the great importance of an adequately performed and rigorously applied protocol by all team members should not be underestimated. The objective of this article is to explain the basis of the details of this procedure in a clear and realistic way.

Intraoperative and postoperative complications of penile implant surgery. Diagnosis and treatment

We describe the most frequent complications associated with penile implant surgery, paying special attention to their practical management. We have analyzed preoperative complications and postoperative complications separately. The intraoperative include perforation of the corpora cavernosa during dilation, cylinder cross-over or cross-placement and urethral injury during implantation. The most frequent postoperative complications are mechanical failure, cylinder erosion and prosthesis infection. We emphasize on rescue surgery and reimplantation techniques in cavernous tissue fibrosis.

Analysis of satisfaction and surgical outcomes of a major ambulatory surgery program for penile implant

INTRODUCTION AND OBJECTIVE

Penile prosthesis (PP) surgery is performed in many institutions as an inpatient procedure. We have recently initiated a major ambulatory surgery (MAS) program, thus reducing the hospital stay. The objective of this study was to assess the feasibility, complications and satisfaction of the implantation of outpatient surgery PP program in our hospital.

MATERIAL AND METHODS

Retrospective observational study evaluating the results and satisfaction of PP implanted as an outpatient procedure in Bellvitge University Hospital during 2018.

RESULTS

During 2018 we implanted 49 PP: 27 (55%) inpatient surgeries vs. 22 (45%) outpatient surgeries. Of these 22, 2 (9%) were second implants. All patients underwent both general anesthesia and crural, proximal dorsal nerve and transversus abdominis plane block (TAP). Complication rates between inpatient and outpatient procedures were similar, 2 (7%) and 1 (5%), respectively, without reporting infections or requiring PP removal. Postoperatively, a satisfaction telephone survey was conducted in 19 (86%) patients: 16 (84%) considered the time of hospital stay as appropriate, 15 (79%) would have preferred to be operated again in an outpatient care setting and 15 (79%) would recommend it. The patients' main concerns were related to being at home with no medical assistance at home and about coming back the next day for drainage removal. All patients reported well-controlled pain without requiring opioid intake in any case.

CONCLUSIONS

In our series, PP implantation in an ambulatory care setting is feasible and safe. Although there are some aspects that should be improved, the program showed acceptable satisfaction rates and an adequate postoperative pain control, neither raising the administration of opioids, nor increasing complications and re-admission rates.

Innovating Incrementally: Development of the Modern Inflatable Penile Prosthesis

PURPOSE OF REVIEW

The inflatable penile prosthesis (IPP) was introduced in 1973. Since that time, the fundamental design of the IPP has not changed, but numerous improvements to the device, surgery, and peri-operative management have resulted in a modern IPP with excellent reliability, infection control, safety profile, and user experience.

RECENT FINDINGS

We describe important modifications to the IPP and review available data assessing the impact of these changes. We also discuss possible changes to the IPP that would result in continued improvement. Since its introduction in 1973, changes to the penile prosthesis have resulted in significant improvements in reliability, infection control, safety, and user experience. Design changes are anticipated to continue, resulting in a better and more versatile penile prosthesis.

A Surgeon's Guide to the Various Antibiotic Dips Available During Penile Prosthesis Implantation

PURPOSE OF REVIEW

Inflatable penile prosthesis (IPP) is a treatment for erectile dysfunction. IPPs have undergone improvements; however, post-surgical infections still occur. Furthermore, the type of pathogens infecting the implants has changed recently from Gram-positive to Gram-negative bacteria and fungi due to advances in antibiotic dips targeting the skin flora. To protect against infection, the AMS 700 is pre-coated with InhibiZone (mixture of Rifampin/Minocycline) and the Coloplast Titan, with several antibiotic dip options of differing efficacies. This review discusses strategies to decrease the infection rates in implant surgery, focusing on antibiotic dips.

RECENT FINDINGS

Current research endorses the use of rifampin/gentamicin as the most studied combination; however, some studies have utilized different dips for additional coverage including the InhibiZone on the AMS 700. With the increasing prevalence of diabetes and Gram-negative organisms, there is a need to develop strategies for increased coverage against infections. Controlled studies with different antibiotic combinations are needed to identify the ideal cocktail to decrease infection.

Penile implants: a look into the future

Inflatable penile prosthesis (IPP) has been around since the 1970’s as a durable and one-time cure for erectile dysfunction (ED). For the past 40 years, many changes have been made to make the device better and currently IPP boasts a high percentage of long-term patient satisfaction. The next paradigm shift in IPP treatment for ED is upon us. Funding for ED related medications and devices has been a hot topic in health policy over the last 10 years. This suggests that the device must improve and patient advocacy and education must increase for IPP to remain as a viable solution for ED. In this paper, we conduct a literature search for innovations in IPP and argue that IPP must constantly improve to compete with oral, injectable, shockwave, and potentially gene therapies.

Prevention, identification, and management of post-operative penile implant complications of infection, hematoma, and device malfunction

Penile prosthesis implant surgery is an effective management approach for a number of urological conditions, including medication refractory erectile dysfunction (ED). Complications encountered post-operatively include infection, bleeding/hematoma, and device malfunction. Since the 1970s, modifications to these devices have reduced complication rates through improvement in antisepsis and design using antibiotic coatings, kink-resistant tubing, lock-out valves to prevent autoinflation, and modified reservoir shapes. Device survival and complication rates have been investigated predominately by retrospective database-derived studies. This review article focuses on the identification and management of post-operative complications following penile prosthetic and implant surgery. Etiology for ED, surgical technique, and prosthesis type are variable among studies. The most common post-operative complications of infection, bleeding, and device malfunction may be minimized by adherence to consistent technique and standard protocol. Novel antibiotic coatings and standard antibiotic regimen may reduce infection rates. Meticulous hemostasis and intraoperative testing of devices may further reduce need for revision surgery. Additional prospective studies with consistent reporting of outcomes and comparison of surgical approach and prosthesis type in patients with variable ED etiology would be beneficial.

A history of penile implants

Erectile dysfunction (ED) has long been described by physicians and patients, with treatments for ED proposed starting in the 8^th century BC. In the last 50 years, however, there have been many advances in medical and surgical management of ED, notably the introduction of the inflatable penile prosthesis (IPP) in 1973 and phosphodiesterase type 5 inhibitors (PDE5Is) in 1998. Here we review the evolution of the IPP from 1973 through the current day. The 3-piece device was first described in 1973 by Dr. F. Brantley Scott, who helped found American Medical Systems (AMS) to market and sell the device. In 1983, Mentor (now Coloplast) started marketing a competing device. AMS and Mentor have made multiple modifications to the device over the years, which have increased rigidity, durability and patient satisfaction, and have decreased surgical variability, post-operative infection and spontaneous inflation. Today, the IPP is a safe and effective option for many men who have failed medical therapies, with high satisfaction from both patients and partners.

30-day adverse event rates following penile prosthesis surgery: an American College of Surgeons National Surgical Quality Improvement Program based evaluation

Background

Commonly utilized as a third-line therapy for erectile dysfunction (ED) management, the penile prostheses have become a staple treatment for ED refractory to pharmacological interventions. There is however a paucity of data in the literature pertaining to short-term adverse outcomes following penile prosthesis surgery. We thus sought to leverage the American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) to evaluate such outcomes within 30 days of surgery in these patients. We hypothesized that such data will lead to a more informed patient-physician consultation.

Methods

Relying on the ACS-NSQIP database [2005–2013], patients undergoing penile prosthesis placement were identified utilizing the Current Procedural Terminology (CPT) codes: 54400, 54401, 54405, 54406, 54407, 54408, 54410, 54411, 54416 and 54417. Outcomes assessed included system-wise categorized complications, length-of-stay (LOS), and re-intervention, readmission and 30-day mortality rates. Descriptive statistics were used to analyze available data. Multivariate analysis could not be performed due to small sample size.

Results

Overall, 98 cases of patients who underwent surgery for penile prosthesis placements between the years 2005 and 2013 were reported by the ACS-NSQIP affiliated hospitals. The median age was 65 years (interquartile range, 58–70 years). The overall 30-day complication rate was 11.3% (n=11); 5 of the 11 complications were infectious in etiology, and three were a postoperative blood transfusion event. The median LOS was 1 day. One (1.0%) patient needed to return to the operating room, two patients (2.6%) were readmitted and there was one (1.0%) death within 30 days of the original surgery.

Conclusions

Surgery for penile prosthesis appears to be a safe operation despite the routinely advanced age of the patients requiring it. Complications in the immediate postoperative setting are usually infectious. This data can be used in the clinical setting for a more informed patient-physician discussion and patient expectation management.

Longitudinal and Horizontal Load Testing of Inflatable Penile Implant Cylinders of Two Manufacturers: An Ex Vivo Demonstration of Inflated Rigidity

INTRODUCTION

Since the inception of the inflatable penile prosthesis, a new era has been ushered in for the management of erectile dysfunction. Despite multiple innovations to improve function and reliability, there are no current data comparing the biomechanical properties of these devices.

AIM

To compare the resistance of the Coloplast Titan (Minneapolis, MN, USA) with that of the AMS 700 LGX (Minnetonka, MN, USA) penile prosthesis cylinders to longitudinal (penetration) and horizontal (gravity) forces.

METHODS

We compared two cylinder sizes from each company: the Coloplast Titan (18 and 22 cm) and the AMS 700 LGX (18 and 21 cm). To evaluate axial rigidity, which simulates forces during penetration, we performed a longitudinal load compression test to determine the load required to cause the cylinder to kink. To test horizontal rigidity, which simulates the horizontal forces exerted by gravity, we performed a modified cantilever test and measured the degrees of bend for each device. All devices were tested at 10, 15, and 20 PSI to simulate in vivo pressures.

MAIN OUTCOME MEASURES

The main outcome measurement for the longitudinal load test (penetration) was the force required for the inflated cylinder to bend, thereby affecting its rigidity. The main outcome for the horizontal rigidity test (gravity) was the angle of displacement, in which a smaller angle represents a more horizontally rigid device.

RESULTS

Longitudinal column testing (penetration) demonstrated that less force was required for the AMS device to kink compared with the Coloplast implant across all three fill pressures tested. The Coloplast Titan also had a smaller angle of displacement at the modified cantilever test (gravity) compared with the AMS implant across all fill pressures.

CONCLUSION

The Coloplast Titan demonstrated greater resistance to longitudinal (penetration) and horizontal (gravity) forces in this study. The AMS device was very sensitive to fill pressures. In contrast, the Coloplast Titan's ability to resist these forces was less dependent on the device fill pressure.

Penile prosthesis implant: scientific advances and technological innovations over the last four decades

Despite introduction of oral phosphodiesterase type 5 inhibitors and intracavernosal vasoactive agents, penile prosthesis implant remains a relevant and desired option with sales of penile prostheses continue to stay high, as many men became refractory to medical therapy and/or seeking a more effective and permanent therapy. There are two types of penile prosthesis implants: inflatable and non-inflatable types, and the inflatable penile implants can be subdivided into single-, two- and three-piece devices. Non-inflatable penile prosthesis (non-IPP) may be referred to as semi-rigid rod or malleable prosthesis. IPP is considered a superior option to malleable prosthesis as it produces penile rigidity and flaccidity that closely replicates a normal penile erectile function. Since the introduction of IPP by Scott in 1973, surgical landscape for penile prosthesis implantation has changed dramatically. Advances in prosthesis design, device technologies and surgical techniques have made penile prosthesis implant a more natural, durable and reliable device. The following article reviews the scientific advances and technological innovation in modern penile prosthesis implants over the last four decades.

Minimising the risk of device infection in penile prosthetic surgery: a UK perspective

We have reviewed articles published on penile prosthetic infection in Medline and EMBASE databases from 2000 to 2012 with the intention of signposting ‘best evidence’ for the UK prosthetic implanter. Using the Oxford Centre for Evidence-based Medicine Levels of Evidence (LE), no paper exceeded an LE of 2b and the majority were LE 4 (case series) and LE 5 (expert opinion). This is not surprising from a UK perspective since HES data for 2009 to 2010 reported 263 penile prosthetic surgeries performed in 35 hospitals, with only five hospitals performing 15 or more. Our literature review suggests that the use of antibiotic-coated IPPs and measures aimed at reducing inoculating bacteria into the surgical wound with alcohol skin preparation, a no-touch technique and peri-operative antibiotic use are most important in minimising the risk of device infection. The use of post-operative antibiotics is contentious (LE 5). It remains unproven whether diabetics have a higher rate of prosthetic infection compared to nondiabetics. In cases of re-implantation for mechanical failure, it remains debatable whether a washout technique should be used and indeed uncertainty remains regarding the pathological role of biofilm in the causation of device infection in this scenario. A washout technique during salvage penile prosthetic surgery for device infection is advocated. Further research on biofilm may offer the best chance of reducing the incidence of device infections overall.

Inflatable penile prosthesis (IPP): diagnosis of complications

Inflatable penile prostheses are a common treatment for erectile dysfunction that is unresponsive to less-invasive measures. Complications can arise at the time of the placement of the prosthesis or at a later date. Complications may be related to infection and/or mechanical failure of one or more of the prosthesis components including cylinder, reservoir, pump, and tubing. Mechanical failure includes kinking, migration, and aneurysmal dilation of the cylinder, erosion of the tunica albuginea of the corpora cavernosum by the cylinder, disconnection of the tubing, and migration of the reservoir. MRI of the entire components with the cylinders in both flaccid and inflated states is the best imaging modality available to image patients with suspected implant complications.

Technological Improvements in Three-Piece Inflatable Penile Prosthesis Design over the Past 40 Years

INTRODUCTION

The advent of the penile prosthesis revolutionized the treatment of erectile dysfunction (ED), resulting in near-complete treatment efficacy and high patient satisfaction rates. While several types of penile prosthesis are available, the inflatable penile prosthesis (IPP) is the most commonly used device in the United States.

AIMS

To describe the key modifications to IPPs from the two major manufacturers-American Medical Systems (AMS) and Coloplast-since the invention of the IPP, and to relate these changes to improvements in prosthesis function and patient outcomes based on available literature.

METHODS

Review and evaluation of the literature between 1973 and present describing modifications in IPP design and the influence of these modifications on IPP durability and patient-related factors.

MAIN OUTCOME MEASURES

Data describing the impact of iterative improvements in three-piece IPP design on device function, durability, and patient outcomes.

RESULTS

There were progressive improvements in IPP technology from both major manufacturers not only on the durability of the prosthesis but also on patient outcomes, with fewer device failures and lower infection rates. Notable improvements include incorporation of kink-resistant tubing, changes in the weave or addition of shear- and infection-resistant coatings to cylinder layers, pump and tubing connection modifications, the addition of rear tip extenders, and the incorporation of lockout valves to prevent autoinflation.

CONCLUSIONS

Numerous incremental modifications to the IPP from both major manufacturers since its invention have increased its durability and improved patient outcomes.

A practical overview of considerations for penile prosthesis placement

Penile prostheses have remained the gold-standard therapy for medically refractory erectile dysfunction (ED) since their popularization. Advances in device design and surgical techniques have yielded improved rates of infection, satisfaction, and mechanical survival of devices. Operative techniques in penile prosthesis surgery include the use of adjunctive procedures (such as ventral phalloplasty and release of the suspensory ligament), management of penile fibrosis, and manoeuvres to correct Peyronie's-disease-related curvature. Complications include urethral and corporal perforation, crossover, infection, impending erosion, and/or supersonic transporter deformity. Long-term data regarding mechanical, overall, and infection-free survival demonstrate excellent results, and, given the consistently high satisfaction rates and limited alternatives for medically refractory ED, penile prostheses are likely to remain a relevant and important treatment strategy for the foreseeable future.

History, Contemporary Outcomes, and Future of Penile Prostheses: A Review of the Literature

INTRODUCTION

Since their introduction, penile prostheses have consistently remained a superior treatment option for men with erectile dysfunction (ED) refractory to conservative measures. Ongoing enhancements to prosthetic design, materials, and surgical techniques have resulted in improved outcomes.

AIM

To review available literature on notable historical advancements and improvements of the penile prosthesis, summarize contemporary outcomes of recent devices, and discuss possible future directions of the penile prosthesis.

METHODS

A PubMed search was performed of all articles published from 1960 to present relating to penile prosthesis. Priority was given to series with 12 months of follow-up or greater, larger series, and studies reporting on outcomes of more recent prosthetic models.

MAIN OUTCOME MEASURES

Main outcomes included historical review of improvements leading to, and contemporary series reporting on rates of mechanical failures, infections, and satisfaction with penile prostheses.

RESULTS

Penile prostheses have undergone numerous enhancements since initial reports of synthetic materials utilized in the 1950s. Among others, recent notable device enhancements include Parylene coating, Bioflex® material, Inhibizone^TM antibacterial impregnation, hydrophilic coating, lockout valves, and easy release pump mechanisms, all of which have improved mechanical reliability, reduced infection rates, and/or improved patient satisfaction with penile prostheses. Contemporary series of 3-piece penile prostheses report mechanical survival of 81-94%, 68-89%, and 57-76% at 5, 10, and 15 years, respectively. Infection rates of current devices are 1-2% in first-time, low-risk populations, and 2-3% for higher risk groups, with patient and partner satisfaction at 92-100% and 91-95%, respectively. Two-piece and malleable devices are associated with slightly higher mechanical reliability and decreased patient satisfaction. Minimal data currently exist on the outcomes of selected patient populations, including Peyronie's disease and corporal fibrosis.

CONCLUSIONS

Penile prostheses are associated with excellent, long-term outcomes and remain the gold-standard treatment for men with refractory ED. Additional research with prospective studies utilizing objective measures and standardized questionnaires is required. Trost L and Hellstrom WJG. History, contemporary outcomes, and future of penile prostheses: A review of the literature. Sex Med Rev 2013;1:150-163.

Erectile Dysfunction: A Review of Historical Treatments With a Focus on the Development of the Inflatable Penile Prosthesis

Erectile dysfunction has been a concern for men since the beginning of written history. For many men it can lead to severe psychological distress and humiliation. The treatment of erectile dysfunction has advanced significantly over the past 200 years. Men today are presented with many more viable therapy options leading to improved efficacy and more satisfactory sex lives. The objective of this article is to explore historical options for the treatment of erectile dysfunction, with particular emphasis on the development and progression of the inflatable penile prosthesis.

Evolution of penile prosthetic devices

Penile implant usage dates to the 16th century yet penile implants to treat erectile dysfunction did not occur until nearly four centuries later. The modern era of penile implants has progressed rapidly over the past 50 years as physicians' knowledge of effective materials for penile prostheses and surgical techniques has improved. Herein, we describe the history of penile prosthetics and the constant quest to improve the technology. Elements of the design from the first inflatable penile prosthesis by Scott and colleagues and the Small-Carrion malleable penile prosthesis are still found in present iterations of these devices. While there have been significant improvements in penile prosthesis design, the promise of an ideal prosthetic device remains elusive. As other erectile dysfunction therapies emerge, penile prostheses will have to continue to demonstrate a competitive advantage. A particular strength of penile prostheses is their efficacy regardless of etiology, thus allowing treatment of even the most refractory cases.

The evolution of the inflatable penile prosthetic device and surgical innovations with anatomical considerations

Historically, early surgical treatment for erectile dysfunction involved the placement of rigid devices outside of the corpora cavernosa. This practice resulted in high rates of erosion and infection. Today, most urologists in the United States place an inflatable penile prosthesis (IPP) with an infection-retardant coating inside the corpora cavernosa. In addition to changes in the type of implant used, surgical techniques have evolved greatly in recent years, resulting in reduced operating times, lower infection rates, and improved outcomes. However, anatomical considerations have directed the prosthetic surgeon to improve patient outcomes and satisfaction rates by employing both new surgical techniques and postoperative maneuvers.

Inflatable penile prostheses for the treatment of erectile dysfunction

Male erectile dysfunction is a common medical condition. Recent advances in our understanding of corpora cavernosa physiology have resulted in three effective oral medications (sildenafil, vardenafil and tadalafil--all phosphodiesterase type 5 inhibitors), which can effectively treat many men with erectile dysfunction. However, a large number of men are not adequately treated by these medications due to their cost, side effects, contraindications or lack of a satisfactory erectile response. For men who do not respond to less invasive therapy, an inflatable penile prosthesis can provide an excellent alternative. This article will review and critique the currently available inflatable penile prostheses in the treatment of erectile dysfunction.

Korean Society for Sexual Medicine and Andrology (KSSMA) Guideline on Erectile Dysfunction

In February 2011, the Korean Society for Sexual Medicine and Andrology (KSSMA) realized the necessity of developing a guideline on erectile dysfunction (ED) appropriate for the local context, and established a committee for the development of a guideline on ED. As many international guidelines based on objective evidence are available, the committee decided to adapt these guidelines for local needs instead of developing a new guideline. Considering the extensive research activities on ED in Korea, data with a high level of evidence among those reported by Korean researchers have been collected and included in the guideline development process. The latest KSSMA guideline on ED has been developed for urologists. The KSSMA hopes that this guideline will help urologists in clinical practice.

Penile prosthesis surgery in the management of erectile dysfunction

Introduction

We reviewed retrospectively the use of penile prostheses, including the indications and complications of penile prosthesis surgery.

Methods

We identified publications and the reported advances in penile prosthesis surgery between 1987 and 2012 in Pub-Med, and published information from American Medical Systems, Inc. (Minnetonka, MN, USA) and Coloplast Corporation (Humlebaek, Denmark), using the keywords ‘penile prosthesis’, ‘erectile dysfunction’, ‘mechanical reliability’, ‘complications’ and ‘infection’.

Results

We describe the novel indications for the use of penile prostheses, the significant advances in implant designs with improved mechanical reliability, the changing landscape of device infection, and the current management of complications. Sixty-eight publications with a grade A, B and C level of evidence are cited.

Conclusion

The clinical indications to implant a penile prosthesis have expanded beyond organic erectile dysfunction. With the many different devices currently available, the choice of which device to implant can be tailored based on an individual’s unique medical conditions, manual dexterity and expectations, and surgeon preference. There must be a conscious effort to prevent device infection, in the light of the development of increasingly virulent organisms. Penile prosthesis surgery is an integral part of the treatment of erectile dysfunction when non-surgical options fail or are contraindicated.

Biofilm formation on coated silicone tympanostomy tubes

OBJECTIVES

Tympanostomy tube (TT) surface modifications have been promoted as a means of reducing biofilm formation, otorrhea, and occlusion. The goal of this study was to determine if biofilm formation on silicone TTs could be prevented by commercially available surface coatings.

METHODS

Silicone TTs with and without polyvinylpyrrolidone (PVP) or/and silver oxide were exposed to human plasma and cultured with Pseudomonas aeruginosa or Staphylococcus aureus (22 TTs per group). After 4 days, antibiotics were added to kill planktonic bacteria. Biofilm formation was assessed by quantitative bacterial counts and scanning electron microscopy.

RESULTS

PVP, silver, and PVP-silver coatings reduced P. aeruginosa biofilm formation relative to silicone by over 1 log (p<0.0001). PVP was superior to silver (p=0.04) and PVP-silver (p<0.0001). PVP and PVP-silver coatings increased S. aureus biofilm formation nominally (p=0.01 & 0.003).

CONCLUSION

PVP and silver coatings reduce P. aeruginosa biofilm formation on silicone TTs. Combining PVP and silver coatings does not further improve biofilm resistance. TT surface coatings warrant further study through clinical trials.

Long-term revision rate due to infection in hydrophilic-coated inflatable penile prostheses: 11-year follow-up

INTRODUCTION

Penile implant surgery continues to be an important option for men with erectile dysfunction. Advancements in technology of implants have contributed to improved survival from mechanical breakdown. Prosthesis infection remains a serious adverse event. For the last 8 years, the Titan implant (Coloplast Corporation, Minneapolis, MN, USA) has been available with an infection-retardant polyvinylpyrrolidone coating.

AIM

To compare the infection rates between coated three-piece inflatable penile prostheses (IPPs) with the previous non-coated model.

MAIN OUTCOME MEASURES

Infection-related revisions reported in the physician-generated, manufacturer-tabulated patient information forms (PIFs).

METHODS

PIFs reported into the voluntary, post-market registry of Coloplast Corporation from July 14, 2000 to September 30, 2011 were retrospectively reviewed. Infection-related revisions entered into the product evaluation database for coated and non-coated IPPs were compared. Data were analyzed using Pearson's chi-squared test.

RESULTS

The database included 36,391 PIFs related to primary IPP implantation. At 11 years of follow-up, 4.6% (7,031) of non-coated IPPs were removed or replaced due to infections, whereas 1.4% (29,360) of hydrophilic-coated implants reported replacements due to device infections. The hydrophilic coating of the IPP components makes the device slippery and prevents bacterial attachment. The hydrophilic coating allows rapid absorption of antibiotics in an aqueous solution and allows these water-soluble antibiotics to elute off the device into the implant spaces. Unfortunately, information pertaining to what agents were used in the studies patients was not tabulated. The rate of revision due to device infection was reduced 69.56% in patients with hydrophilic-coated IPPs (P<0.001).

CONCLUSION

To the best of our knowledge, this is the longest post-marketing registry report related to IPP infections. At 8 years of follow-up, the hydrophilic-coated IPPs demonstrated a significant reduction in revision rates due to infection when compared with the 11-year follow-up of non-coated implants. Since there was no information or uniformity of antibiotics used in the soaking solution, it is uncertain which antibiotic selection provided the best results. In vitro testing against known infectious agents may further benefit IPP patients by reducing the prosthesis infection rate.