madman
Super Moderator
ABSTRACT
Background: During the last century, surgical management of erectile dysfunction has evolved from an experimental concept to a core treatment modality with widespread use among the men’s health community. Over time, innovations in materials, mechanical design elements, device coatings, and surgical techniques have provided patients with low-risk, reliable, and reproducible erectile function with high satisfaction rates.
Aim: To provide a foundation for future innovation by improving understanding of historical penile prosthetics and the rationale behind incremental technological improvements for the contemporary Men’s health physician.
Methods: A literature review was conducted to generate a comprehensive review of historical technological innovations in penile implant surgery. Companies with FDA-approved penile prosthetics in use in the United States were contacted for information regarding technological innovations in the past and future devices in development. A separate literature review was performed to identify any significant future device design elements being tested, even in the ex vivo setting, which may have future clinical applications.
Outcomes: Technological innovations in penile implant surgery were described.
Results: Current options for the prosthetic surgeon include malleable penile prostheses (MPP), self-contained (2-piece) inflatable penile prostheses, and multicomponent (3-piece) inflatable penile prostheses. Current MPPs consist of a synthetic coated solid core that allows for manipulation of the penis for concealability while maintaining sufficient axial rigidity to achieve penetration when desired. Multi-component (3-Piece) IPPs currently include the Coloplast Titan and Boston Scientific/AMS 700 which consist of a fluid reservoir, intrascrotal pump, and intracavernosal cylinders. The devices have undergone numerous design updates to the cylinders, pump, reservoir, tubing, and external coatings to increase reliability and decrease short- and long-term complications.
Clinical Implications: Future innovations in penile prosthetic surgery seek to broaden the indications and applicability to the transgender community and improve both safety and functionality for patients and partners.
Strengths & Limitations: The review is limited primarily to penile prosthetics approved for current or historical clinical use in the United States and may not be representative of the global prosthetic environment. Additionally, the research and development of future innovations, particularly those provided by device manufacturers, is likely limited by non-disclosure to maintain a competitive advantage.
Conclusions: Penile prosthetic surgery will undoubtedly remain integral to the treatment of erectile dysfunction, and education regarding the current state of technological innovation will empower the prosthetic surgeon and biomedical engineering community to improve contemporary patient care and drive the development of the next generation of implantable penile prosthetics.
INTRODUCTION
Penile prosthetic surgery remains a critical tool in the urologic surgeon’s armamentarium for the management of erectile dysfunction, Peyronie’s disease, and in female-to-male gender reassignment operations. The first phalloplasty was described in 1936 by Nikolaj Bogoras using autologous human rib cartilage within a tabularized abdominal flap, marking the beginning of penile implant surgery.1 A decade later the first female to male gender reassignment operation was performed by Dr. Harold Gillies on a fellow physician and his technique remained the standard for many years. Then, in 1952 Goodwin and Scott created the first artificial, acrylic penile prosthesis which was shortly followed by a silicone-based implant in 1964 by Lash et al. Although marking the transition to the utilization of prosthetic material for erectile restoration, the early implant materials left significant opportunity for improvement with respect to surgical outcomes and functionality.2 Finally, in 1973 Scott et al described the first inflatable penile prosthesis (IPP) which has remained the model for contemporary penile implant surgery, albeit with numerous iterations and improvements.3 Advances in functional outcomes and patient satisfaction are an ongoing endeavor representing innovations in implant technology, perioperative management, and refinements in surgical technique. Herein, technological advances in implant surgery will be presented to increase surgeon awareness and understanding of contemporary devices and components and to highlight the future opportunities for improvement.
*MALLEABLE PENILE PROSTHETICS
*SELF-CONTAINED (2-PIECE) INFLATABLE PENILE PROSTHETICS
*MULTICOMPONENT (3-PIECE) INFLATABLE PENILE PROSTHETICS
-Pump
-Reservoir
-Cylinders
-Rear Tip Extenders (RTE)
-Coatings
*Improvements in Operative Techniques
*FUTURE DEVELOPMENTS IN PENILE PROSTHETIC SURGERY
Patient satisfaction has been shown to be similar between device manufacturers Coloplast and AMS/Boston scientific, and overall satisfaction across studies is typically around 90%−95% for contemporary devices.25 Invariably both Coloplast and AMS/ Boston Scientific is continuing to develop new and improved pump, cylinder, and reservoir designs as well as improved procedural accessories. A potential “touchless” IPP has been reported in preclinical studies that removes the need for manual pumping and is controlled by an external remote that routes fluid from the reservoir to the cylinders and contains an implantable battery similar to a sacral neuromodulation device. Another current area of advancement is in transgender surgery applications of inflatable and malleable penile prostheses. Internationally there are neophallus specific inflatable prostheses (eg, ZSI 475 FtM) which have been available in Europe since March 2016. An analysis of 20 patients showed 85.7% were able to have penetrative sexual intercourse and 92.8% were satisfied or very satisfied with the prosthesis; the overall revision rate was 19%.26 Zephyr’s 2021 model 475 FtM will have a removable glans option to make the implant further customizable to a patient’s individual neophallus (Figure 7) Additionally, thermally activated prostheses consisting of an exoskeleton of temperature tuned nitinol and Ni-TI alloy has been created and demonstrated similar mechanical parameters to IPPs in laboratory studies.27 Induction of erection is achieved by using an external magnetic induction wand and has been tested in animal and cadaveric models with promising early results. Other ideas have included augmentation to normal erectile function such as the creation of vibrating penile implants to enhance partner satisfaction; however, the increased device complexity and widespread availability of external vibration devices may preclude such developments. Additionally, the implications are questionable as clitoral stimulation is usually most pleasurable to partners which further favors using external vibrators instead.28 Penile prostheses have been a reliable option for men with ED for nearly 50 years and will undoubtedly remain a vital tool to urologic surgeons going forward. Further studies and innovations in device technology and surgical technique will increase patient and partner satisfaction by more reliably and accurately replicating normal erectile function.
CONCLUSIONS
Over the last 50 years, the IPP has solidified a central role in the surgical treatment of ED. Technological advancements in IPP design has been instrumental in improving patient safety, satisfaction, and device longevity. An understanding of the history of IPP design will drive future innovation to further improve ease of use, safety, reliability and also expand options for select patient populations such as the transgender community.
Background: During the last century, surgical management of erectile dysfunction has evolved from an experimental concept to a core treatment modality with widespread use among the men’s health community. Over time, innovations in materials, mechanical design elements, device coatings, and surgical techniques have provided patients with low-risk, reliable, and reproducible erectile function with high satisfaction rates.
Aim: To provide a foundation for future innovation by improving understanding of historical penile prosthetics and the rationale behind incremental technological improvements for the contemporary Men’s health physician.
Methods: A literature review was conducted to generate a comprehensive review of historical technological innovations in penile implant surgery. Companies with FDA-approved penile prosthetics in use in the United States were contacted for information regarding technological innovations in the past and future devices in development. A separate literature review was performed to identify any significant future device design elements being tested, even in the ex vivo setting, which may have future clinical applications.
Outcomes: Technological innovations in penile implant surgery were described.
Results: Current options for the prosthetic surgeon include malleable penile prostheses (MPP), self-contained (2-piece) inflatable penile prostheses, and multicomponent (3-piece) inflatable penile prostheses. Current MPPs consist of a synthetic coated solid core that allows for manipulation of the penis for concealability while maintaining sufficient axial rigidity to achieve penetration when desired. Multi-component (3-Piece) IPPs currently include the Coloplast Titan and Boston Scientific/AMS 700 which consist of a fluid reservoir, intrascrotal pump, and intracavernosal cylinders. The devices have undergone numerous design updates to the cylinders, pump, reservoir, tubing, and external coatings to increase reliability and decrease short- and long-term complications.
Clinical Implications: Future innovations in penile prosthetic surgery seek to broaden the indications and applicability to the transgender community and improve both safety and functionality for patients and partners.
Strengths & Limitations: The review is limited primarily to penile prosthetics approved for current or historical clinical use in the United States and may not be representative of the global prosthetic environment. Additionally, the research and development of future innovations, particularly those provided by device manufacturers, is likely limited by non-disclosure to maintain a competitive advantage.
Conclusions: Penile prosthetic surgery will undoubtedly remain integral to the treatment of erectile dysfunction, and education regarding the current state of technological innovation will empower the prosthetic surgeon and biomedical engineering community to improve contemporary patient care and drive the development of the next generation of implantable penile prosthetics.
INTRODUCTION
Penile prosthetic surgery remains a critical tool in the urologic surgeon’s armamentarium for the management of erectile dysfunction, Peyronie’s disease, and in female-to-male gender reassignment operations. The first phalloplasty was described in 1936 by Nikolaj Bogoras using autologous human rib cartilage within a tabularized abdominal flap, marking the beginning of penile implant surgery.1 A decade later the first female to male gender reassignment operation was performed by Dr. Harold Gillies on a fellow physician and his technique remained the standard for many years. Then, in 1952 Goodwin and Scott created the first artificial, acrylic penile prosthesis which was shortly followed by a silicone-based implant in 1964 by Lash et al. Although marking the transition to the utilization of prosthetic material for erectile restoration, the early implant materials left significant opportunity for improvement with respect to surgical outcomes and functionality.2 Finally, in 1973 Scott et al described the first inflatable penile prosthesis (IPP) which has remained the model for contemporary penile implant surgery, albeit with numerous iterations and improvements.3 Advances in functional outcomes and patient satisfaction are an ongoing endeavor representing innovations in implant technology, perioperative management, and refinements in surgical technique. Herein, technological advances in implant surgery will be presented to increase surgeon awareness and understanding of contemporary devices and components and to highlight the future opportunities for improvement.
*MALLEABLE PENILE PROSTHETICS
*SELF-CONTAINED (2-PIECE) INFLATABLE PENILE PROSTHETICS
*MULTICOMPONENT (3-PIECE) INFLATABLE PENILE PROSTHETICS
-Pump
-Reservoir
-Cylinders
-Rear Tip Extenders (RTE)
-Coatings
*Improvements in Operative Techniques
*FUTURE DEVELOPMENTS IN PENILE PROSTHETIC SURGERY
Patient satisfaction has been shown to be similar between device manufacturers Coloplast and AMS/Boston scientific, and overall satisfaction across studies is typically around 90%−95% for contemporary devices.25 Invariably both Coloplast and AMS/ Boston Scientific is continuing to develop new and improved pump, cylinder, and reservoir designs as well as improved procedural accessories. A potential “touchless” IPP has been reported in preclinical studies that removes the need for manual pumping and is controlled by an external remote that routes fluid from the reservoir to the cylinders and contains an implantable battery similar to a sacral neuromodulation device. Another current area of advancement is in transgender surgery applications of inflatable and malleable penile prostheses. Internationally there are neophallus specific inflatable prostheses (eg, ZSI 475 FtM) which have been available in Europe since March 2016. An analysis of 20 patients showed 85.7% were able to have penetrative sexual intercourse and 92.8% were satisfied or very satisfied with the prosthesis; the overall revision rate was 19%.26 Zephyr’s 2021 model 475 FtM will have a removable glans option to make the implant further customizable to a patient’s individual neophallus (Figure 7) Additionally, thermally activated prostheses consisting of an exoskeleton of temperature tuned nitinol and Ni-TI alloy has been created and demonstrated similar mechanical parameters to IPPs in laboratory studies.27 Induction of erection is achieved by using an external magnetic induction wand and has been tested in animal and cadaveric models with promising early results. Other ideas have included augmentation to normal erectile function such as the creation of vibrating penile implants to enhance partner satisfaction; however, the increased device complexity and widespread availability of external vibration devices may preclude such developments. Additionally, the implications are questionable as clitoral stimulation is usually most pleasurable to partners which further favors using external vibrators instead.28 Penile prostheses have been a reliable option for men with ED for nearly 50 years and will undoubtedly remain a vital tool to urologic surgeons going forward. Further studies and innovations in device technology and surgical technique will increase patient and partner satisfaction by more reliably and accurately replicating normal erectile function.
CONCLUSIONS
Over the last 50 years, the IPP has solidified a central role in the surgical treatment of ED. Technological advancements in IPP design has been instrumental in improving patient safety, satisfaction, and device longevity. An understanding of the history of IPP design will drive future innovation to further improve ease of use, safety, reliability and also expand options for select patient populations such as the transgender community.
