madman
Super Moderator
Abstract
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.
Summary 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.
Looking Forward
Current IPPs—a result of decades of innovation by manufacturers and surgeons —are functional, reliable, and safe. While tempting to imagine dramatic design changes to the penile prosthesis, the several decade history of penile prosthesis implantation suggests that future changes will be subtle but numerous, ultimately resulting in devices much better than what we have today. Anticipated areas of further innovation include the following:
Durability While durability is excellent—and much better than in earlier devices—mechanical failures do still occur. Development can focus on reducing the likelihood of fluid leak by identifying and reinforcing points of failure and potentially transitioning away from a hydraulic device.
Extended Indications The current penile prostheses produced by Coloplast and AMS are not designed for implantation in a neophallus (e.g., radial forearm free flap)—a skin tube that originates near the pubis [33•]. Zephyr Surgical Implants (Switzerland) manufacturers an implant (not currently available in the USA) that is specifically designed for a neophallus. It consists of a single cylinder that can be anchored directly to the pubis. Similar models are anticipated to eventually become available in the USA. Dual-cylinder prostheses suitable for implantation in a patient after metoidioplasty, where the erectile bodies are narrower and shorter, would also be welcome and could potentially be used as a tissue expander to increase the size of the phallus.
Anti-microbial Activity While antibiotic coating has reduced the likelihood of a device infection, there are a number of limitations. For example, InhibiZone cannot be modified based on patient- or hospital-specific factors (e.g., allergies, cultures, local antibiotic resistance profiles), while the Coloplast approach of dipping in an antibiotic solution prior to implantation is cumbersome. Future models will likely include non-antibiotic anti-microbial mechanisms incorporated into the implant.
Pump/Patient Experience The pump is currently the main source of patient interaction with the device, and often a major source of patient frustration. As major durability issues have been addressed, usability has become more of a focus for manufacturers. As a result, the pumps are expected to either improve further (e.g., one-touch inflation, easier deflation) or be replaced with other mechanisms (thermal [34••], magnetic [35••], and electronically-activated [36] penile prostheses have been proposed). Other aspects of the patient experience (e.g., comfort, cost, simplified surgery, more physiologic erection) are additional areas for improvement.
Reservoir While great strides have been made in reservoir design and implantation techniques, the placement of the reservoir and need for connections adds time, complexity, and morbidity to the surgery. We expect this component to be ultimately eliminated from the 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.
Summary 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.
Looking Forward
Current IPPs—a result of decades of innovation by manufacturers and surgeons —are functional, reliable, and safe. While tempting to imagine dramatic design changes to the penile prosthesis, the several decade history of penile prosthesis implantation suggests that future changes will be subtle but numerous, ultimately resulting in devices much better than what we have today. Anticipated areas of further innovation include the following:
Durability While durability is excellent—and much better than in earlier devices—mechanical failures do still occur. Development can focus on reducing the likelihood of fluid leak by identifying and reinforcing points of failure and potentially transitioning away from a hydraulic device.
Extended Indications The current penile prostheses produced by Coloplast and AMS are not designed for implantation in a neophallus (e.g., radial forearm free flap)—a skin tube that originates near the pubis [33•]. Zephyr Surgical Implants (Switzerland) manufacturers an implant (not currently available in the USA) that is specifically designed for a neophallus. It consists of a single cylinder that can be anchored directly to the pubis. Similar models are anticipated to eventually become available in the USA. Dual-cylinder prostheses suitable for implantation in a patient after metoidioplasty, where the erectile bodies are narrower and shorter, would also be welcome and could potentially be used as a tissue expander to increase the size of the phallus.
Anti-microbial Activity While antibiotic coating has reduced the likelihood of a device infection, there are a number of limitations. For example, InhibiZone cannot be modified based on patient- or hospital-specific factors (e.g., allergies, cultures, local antibiotic resistance profiles), while the Coloplast approach of dipping in an antibiotic solution prior to implantation is cumbersome. Future models will likely include non-antibiotic anti-microbial mechanisms incorporated into the implant.
Pump/Patient Experience The pump is currently the main source of patient interaction with the device, and often a major source of patient frustration. As major durability issues have been addressed, usability has become more of a focus for manufacturers. As a result, the pumps are expected to either improve further (e.g., one-touch inflation, easier deflation) or be replaced with other mechanisms (thermal [34••], magnetic [35••], and electronically-activated [36] penile prostheses have been proposed). Other aspects of the patient experience (e.g., comfort, cost, simplified surgery, more physiologic erection) are additional areas for improvement.
Reservoir While great strides have been made in reservoir design and implantation techniques, the placement of the reservoir and need for connections adds time, complexity, and morbidity to the surgery. We expect this component to be ultimately eliminated from the penile prosthesis
