Abstract

Despite significant scientific advances in the modern three-piece inflatable penile prosthesis implant surgery, it is not without surgical risks and can carry additional cosmetic and psychosocial consequences in poorly selected and consented individuals. To address this problem, an international group of key opinion leaders and high-volume prosthetic surgeons reviewed the current guidelines and clinical evidence, discussed their experiences, and formed a consensus regarding inflatable penile prosthesis surgery. The findings of this consensus panel were presented at the 17th biennial Asia Pacific Society of Sexual Medicine scientific meeting. The experts concluded that proper patient selection, informed consent and strict adherence to safe surgical principles are important to optimize clinical outcomes. Furthermore, most intraoperative complications, if recognized, can be addressed intraoperatively to enable placement of the device at the time of initial surgery. Men with significant corporal fibrosis due to Peyronie’s disease, prior prosthesis explantation and priapism, and men who have undergone construction of a neophallus, as well as men who receive concurrent continence surgery, are complex cases requiring additional care and advanced techniques to obtain optimal surgical outcomes. Variability in patient care — in terms of postoperative antibiotic use, pain management, scrotal care, and cycling of the penile prosthesis implant — must be reduced to enable optimization and assessment of outcomes across patient groups.

Introduction

The introduction of the modern inflatable penile prosthesis (IPP) in 1974 completely revolutionized the treatment for erectile dysfunction (ED)¹. For nearly 50 years, considerable advances have been made in IPP technology and, coupled with improved scientific knowledge in terms of perioperative management and innovative surgical techniques, IPP surgery has been accepted as an effective and safe treatment for ED in many men².

Categorization of the IPP can largely be divided into single-piece, two-piece, and three-piece prostheses, based on whether the devices have a small reservoir at the end of each cylinder (single-piece) or attached to the pump (two-piece), or a larger (separate) reservoir that is connected to the pump (three-piece). Several key factors, including patient preference, surgeon experience, underlying reasons for surgery, manual dexterity, cost, penile size, and prior penile surgery, will contribute to decision making regarding the type of IPP surgery². Non-inflatable or malleable penile prostheses are an alternative to IPPs, and these simpler devices are less costly, easier to perform and are associated with fewer mechanical complications than the IPP². However, the three-piece IPP is often considered a physiologically superior device as it produces penile rigidity and flaccidity that closely resembles a more natural penile erection². Although a two-piece IPP does not require placement of a separate reservoir and is, therefore, easier to place than the three-piece IPP, it has limited cylinder inflation owing to the small volume of fluid in the compartmentalized reservoir and is associated with a lower patient satisfaction rate^2,3,4.

Four main IPP products are available commercially: the Boston Scientific AMS 700 series (American Medical Systems (AMS), now Boston Scientific (BSci), Marlborough, MA, USA), the Coloplast Titan series (Coloplast Corp., Minneapolis, MN, USA), the Zephyr ZSI 475 (Zephyr Surgical Implants SRAL, Geneva, Switzerland), and the Infla10® series (Rigicon Inc., Ronkonkoma, NY, USA). These IPPs have undergone stringent review and clinical testing from relevant national regulatory bodies to ensure that they are safe and mechanically reliable^5,6,7,8. Boston Scientific has manufactured three variations of the AMS 700 series since 1983: the AMS 700 LGX (previously Ultrex), AMS 700 CX and AMS 700 CXR^2,5. The Coloplast Titan series, formerly the Mentor prosthesis, was introduced in 2002 and is available in Titan (standard), Narrow Base (NB) and extra-large (XL) cylinders⁶. The Zephyr ZSI 475 was launched in the early 2010s and the company manufactures the ZSI 475FtM in 2016, specifically for female-to-male gender assignment surgery^2,7. The most recent addition to the IPP market, in 2019, is the Infla10® series (Rigicon Inc., Ronkonkoma, NY, USA), which consists of three different IPP products, namely the Infla10®X, Infla10®AX (anatomical expansion) and Infla10® NarrowBody⁸.

In 2020, clinical recommendations were released by the European Society of Sexual Medicine³; these recommendations focus predominantly on sexual parameters following penile prosthesis implantation, particularly regarding partner expectations, satisfaction in male and phalloplasty cohorts, the effect of penile length, girth and implant type, reservoir placement, and the influence of comorbidities and social circumstances. By contrast, the present consensus statement builds on and expands the surgical aspects of the 4th International Consultation on Sexual Medicine guideline on penile prosthesis implant, which was endorsed by the International Society of Sexual Medicine and published in 2016 (ref.⁴). This consensus was reached by the collective agreement of a group of experts in penile prosthesis surgery and is not endorsed by any society.

This International Penile Prosthesis Implant consensus statement provides a clinical framework around several key domains in patient selection, preoperative evaluation and management of common complications and postoperative care after implantation of a three-piece IPP. A detailed analysis of all relevant studies and a full description of the surgical techniques is not the goal of this consensus statement; instead, it provides an overview of the current evidence-based management strategies for commonly encountered dilemmas when managing patients using IPP. Given the lack of high-quality randomized controlled trials in IPP surgery, specific emphasis is placed on information from narrative review articles and published guidelines .

Conclusions

The increased understanding of IPP surgery and advances in prosthetic surgical techniques have resulted in higher quality products and better surgical outcomes. Continued investment in research and development by device companies has resulted in the creation of a newer generation of penile prosthesis implants, whereas clinical governance by regulatory bodies ensures that these devices remain safe and reliable. Conducting true randomized, placebo-controlled trials in IPP surgery is difficult owing to ethical issues and patient recruitment; thus, more multi-institutional collaborative studies with longer-term follow-up should be undertaken with strict methodology and meaningful objective outcome measures.

Overall, IPP surgery is an effective, safe and durable treatment option for ED. Strict patient selection and counselling are essential, coupled with the use of evidence-based surgical principles and safe surgical techniques, as well as vigilant postoperative care, are paramount to ensuring the best clinical outcomes and patient satisfaction rates.