Overview of Penile Prosthesis Implantation
The penile prosthesis, a device introduced in 1973, has been a helpful solution for individuals suffering from severe erectile dysfunction (ED), which is the inability to get or maintain an erection. This device helps improve sexual function, especially in those who haven’t found other treatments effective. Different types of these implantable devices have been invented over the years.
It is expected that the demand for penile prostheses will increase, as the number of people with ED is predicted to rise to over 322 million worldwide by 2025. This increase is likely due to factors such as an aging population and rising rates of obesity, diabetes, and cardiovascular disease. These conditions are known to influence erectile function, potentially leading to ED.
Anatomy and Physiology of Penile Prosthesis Implantation
The penis has a complex structure which is important to understand when it comes to procedures like penile prosthesis implantation. It consists of three main parts capable of erection: the corpus spongiosum, which wraps the urethra or the tube that carries urine from the bladder out of the body, and two larger bodies known as the corpora cavernosa. These compartments are linked together which allows for fluid exchange.
These parts of the penis are covered by multiple layers of fascia, which play a key role in erection. The outermost layer is the penile skin, enclosing the superficial (Dartos) fascia. Below this is the deep (Buck) fascia, which separates and surrounds the corpus spongiosum and the corpus cavernosum. A strong, non-stretchable layer of connective tissue, the tunica albuginea, protects the cavernosal bodies. When an erection occurs, the corporal bodies are filled with blood which stretches the fibers of the tunica albuginea, causing the penis to become firm.
The blood supply to the penile tissues comes from a variety of sources. The external pudendal arteries provide blood to the penile skin. The internal pudendal artery maintains the deeper blood supply with three main branches to the penis. The blood supply to the urethra and glans, or the tip of the penis, is maintained by the bulbourethral artery and the circumflex arteries. Lastly, the cavernosal arteries become the helicine arteries, which expand due to a certain type of nerve stimulation, resulting in an erection. These blood vessels are interconnected, and the drainage pattern can vary. They usually drain into emissary veins and then move into the dorsal vein of the penis. The periprostatic plexus serves as the final drainage point for these erect tissues.
The penis also has nerve supplies which play an important role in erections. Some nerves stem from the pudendal nerve and are responsible for the sensory and motor nerve supply. The pelvic plexus provides automatic nerve activity. The branches from the original nerve to the penis stem from several points in the spine. In response to certain types of nerve stimulations, a series of neurotransmitters allow the penis muscles to relax, the arteries to widen, the veins to close, and finally, an erection to occur.
Why do People Need Penile Prosthesis Implantation
Currently, putting a penile prosthesis, or an artificial implant, is considered a third option for treating erectile dysfunction (ED), which is the inability to get or maintain an erection. This recommendation comes from the American Urological Association and the European Urological Association. They recommend considering a penile prosthesis for ED that hasn’t been successfully treated with less invasive treatments. These treatments may include phosphodiesterase inhibitors (medication for increasing blood flow), vacuum erection devices (devices that cause an erection by drawing blood into the penis), alprostadil urethral suppositories (medication inserted into the urethra), and injections into the penis.
Other reasons to consider penile prosthesis could be Peyronie’s disease with concurrent ED (a condition where the penis bends due to fibrous scar tissue), scarring in the penis, persistent, painful erection occurring for more than 24 hours, and severe psychologically-induced ED that doesn’t respond to counseling or other treatments.
More recently, penile prosthesis has been found to be beneficial in gender affirmation surgery. However, there are some challenges, like placing a penile prosthesis after creating a penis surgically, known as phalloplasty. Complications such as prosthesis moving around, device protruding from the skin, and common erosions may happen because a tough, supportive layer to hold the cylinders is not present. Therefore, the base of the prosthesis is required to be anchored to a bone. While such surgeries can greatly improve the person’s quality of life, there is a higher risk of complications and the necessity for further surgeries compared to regular penile prosthesis procedures.
When a Person Should Avoid Penile Prosthesis Implantation
Some folks might not be eligible for the operation that places a penile prosthesis – an implanted device that helps with erectile dysfunction – for various reasons:
If you’re dealing with an active infection anywhere on your body, especially within your urinary tract or private parts, the operation might not be suitable for you.
Having unresolved issues while urinating, such as not being able to empty your bladder fully because of a neurogenic bladder (a problem with the nerves that control your bladder) or bladder outlet obstruction (blockage at the base of the bladder) also makes you ineligible for the operation.
If you’re not willing to return for further surgery to adjust or replace the device if needed, the operation isn’t advisable.
Certain pre-existing conditions, mostly issues involving the cardiovascular system (heart and blood vessels), pose a significant risk because having sex could be harmful to your health, making the operation not suitable.
Equipment used for Penile Prosthesis Implantation
Penile prosthesis implantation is a procedure that involves placing an artificial device inside the penis to help with erection. This device can be either malleable (bendable) or inflatable, and the choice depends on several factors such as the surgeon’s experience, the patient’s condition, and the anatomy of the patient’s penis. Both types of devices have been approved by the United States Food and Drug Administration (FDA).
Malleable devices are made up of two firm implants that are inserted within the penis. These can be bent upwards to mimic an erection or downwards when not in use. This type of device is relatively simple to implant and easy for the patient to use. It also has lower chances of malfunctioning. However, the malleable device may cause some discomfort over time and some patients may prefer the feel of the inflatable devices.
The most popular type of penile prosthesis is the 3-piece inflatable model which forms 90% of new implants. This device has two cylinders placed within the penis, a fluid reservoir placed under the muscles or in the abdominal cavity, and a pump in the scrotum to control inflation. This allows for rigid erections when inflation is activated and a natural, flaccid state when deflated.
There is also a 2-piece inflatable prosthesis which has a scrotal pump and smaller reservoirs. It is particularly useful for patients who have had previous abdomen or pelvic surgeries or have received pelvic radiation therapy because it doesn’t require further surgical procedures in the abdomen or pelvis.
In terms of patient satisfaction, over 80% are satisfied with 3-piece devices and over 70% with 2-piece models. Malleable prostheses have similarly high satisfaction rates.
Preparing for Penile Prosthesis Implantation
Before deciding to insert a penile prosthesis, a patient’s medical history and physical condition must be thoroughly assessed. This includes looking at the patient’s symptoms and using a tool called the International Index of Erectile Function (IIEF) to measure the patient’s ability to have an erection. Previous treatments such as injections for erections and any history of prolonged erections, known as priapism, are important to discuss as they can help the doctor predict issues such as corporal fibrosis (scarring in the penis).
In addition to understanding past treatments, it’s also important for the doctor to know about any major surgeries in the pelvic area, such as prostate removal, bladder removal, colorectal surgery, and kidney transplants. These surgeries might change where the doctor makes an incision or where they place the prosthesis. Past conditions such as ischemic priapism (a specific type of painful, prolonged erection) or Peyronie disease (which involves hard, fibrous layers developing in the penis) can also hint towards potential complications. As erectile dysfunction (difficulty getting or maintaining an erection) can be linked to other medical conditions such as heart disease, a complete assessment of the patient’s health and current medicines is necessary. Sometimes, checking if the heart is healthy enough for surgery may be required before carrying out the procedure.
Once all the patient’s history is collected, a thorough physical examination is then completed before proceeding with the operation. The doctor would look at the stomach for any past operation marks that may affect the pelvic area. Any marks from previous radiation treatment for prostate cancer can also be helpful. The physical examination includes assessing the size and shape of the penis, including checking for any curvature or hard lumps.
After the examination, the patient should be thoroughly informed about the option of inserting a penile prosthesis. This discussion should emphasize that this operation offers a permanent solution for erectile dysfunction. It’s important for patients to understand that there might be risks involved with the operation like infection, the prosthesis coming through the skin, dissatisfaction with the results, or the need for future operations. While injuries to the bladder and the tube where urine comes out from (urethra) are rare, they are possible. The doctor should also discuss the aim of the operation and potential complications. As the operation won’t make the penis longer and may in fact lead to a slight shortening, it’s important for patients to have realistic expectations for the operation.
Warding off infections is very important in this kind of surgery, and factors that could lead to a higher chance of infection need to be managed beforehand. For patients with diabetes, keeping blood sugar levels under control is very important as high levels can lead to increased infections after operation. Stopping smoking should also be encouraged as soon as possible as tobacco use can lead to a higher chance of infection at the operation site. Managing these factors before the operation can help improve results and reduce complications.
How is Penile Prosthesis Implantation performed
Before doctors perform a penis implant surgery, they take measures to prevent infection. They usually give the patient antibiotics right before the surgery. Currently, they use a combination of an aminoglycoside antibiotic and cephalosporin or vancomycin. Recently, there’s been some doubt about the effectiveness of these antibiotics, because their use seemed to lead to a higher likelihood of infection after surgery. The same study also suggested that using an antifungal drug could lower the infection risk. They need more research to figure out the best antibiotics to use before penis implant surgery. They might also start using an antifungal drug along with the usual antibiotics.
Doctors prepare your body for the penis implant surgery by cleaning your skin with chlorhexidine-based products, since these seem to lead to better results than iodine-based products. The surgical team also wears two sets of gloves during the procedure, with the inner set used for handling the implant. Moreover, using implants that have been treated with antibiotics /antifungal solutions have been found to decrease the chances of infection. Some actions are backed up by multiple studies that show a lower infection rate with coated implants compared to non-coated ones.
Once the patient is asleep with general anesthesia, the doctors clean and prepare the area between the belly button and middle of the thigh and cover it with sterile material. A catheter is put in place to empty your bladder, minimizing the chances of injury and helping locate the urethra. Depending on the doctor’s preference, the surgical approach for the three-piece inflatable penile prosthesis implant can be through an incision above the public bone or in the scrotum. The surgery consists of several steps involving skin incisions, dissection of the appropriate tissues, and use of tools to create space for the implant in the penis.
Larger cuts can be treated with stitches, while smaller urethral injuries can heal by themselves. After creating enough space in the penis, a fluid-filled sac, or “reservoir,” is placed in a space near your bladder. This fluid will be pumped into the cylinders to create an erection. Your doctors ensure that your bladder is empty before placing the reservoir to prevent any damage. Measurements for the cylinders inside the penis are taken and confirmed by multiple people before the device is prepared for implantation. Needle sutures are attached to each cylinder’s end, which are then passed through the tip of the penis. This process is repeated on the opposite side. After both cylinders are placed, they are checked for appropriate sizing and positioning. The retrieved tissues are then closed.
Lastly, a pump is positioned in the scrotum by creating a pouch. The tissues are then closed above the pump, and the tubes for the pump, cylinders and reservoir are connected. During this process, care is taken to avoid introducing air into the system. Once all components are in place, the skin is closed in two layers and a drain is put in place if the patient is to stay in the hospital overnight. On the next day, the drain and catheter are usually removed. The treated area is covered in gauze to promote healing.
Patients used to be kept overnight in the hospital after receiving a penis prosthesis but as practice evolved, more and more patients are being discharged home the same day barring any complications.
Possible Complications of Penile Prosthesis Implantation
With improvements in technology and surgical methods, complications people experience after having penile prosthesis surgery (a procedure to implant a device in the penis to help with erections) have lessened. Yet, some complications can be quite challenging for doctors. Infection is one major concern after this operation. Acute symptoms such as fever, general discomfort, or fluid draining from the surgery site can appear. Sometimes, the signs are less noticeable and can occur months or even years later. The common method of treatment typically involves using a wide range of antibiotics and taking out all parts of the prosthesis. Some studies, however, have shown that a new implant can be put in immediately after the old one is removed, as long as the area is thoroughly cleaned.
Choosing the right size cylinder to use in the implant can also cause complications. If the cylinders are too short, patients may experience deformities and problems with sexual intercourse. These issues can lead to an unsightly appearance and difficulties during sex. On the other hand, cylinders that are too large can lead to chronic pain and wearing away of the tissue, which may require the implant to be taken out.
Another tricky situation that can arise after the operation is when the pump of the implant moves upward from the scrotum to the penis. This can affect how well the device works and change the look and feel of the penis and scrotum. Doctors try to prevent this by making sure they place the pump and tubing properly during the surgery. Patients can also help prevent this by regularly pulling the pump down into the scrotum.
After the surgery, it’s common for people to have trouble urinating, a condition that can affect up to 27% of patients who’ve gotten penile prosthesis implants. Normally, this issue can be managed by either using a catheter or by teaching patients to self-catheterize, which means they’d insert a tube into their bladder to help pee. People who already have prostate enlargement and are taking certain medications are also at higher risk for this issue.
Another consequence to watch for is the shortening of the penis. This can either occur because of the implant surgery itself or due to prior conditions, including injury, scarring, or previous surgery affecting the penis. However, there are procedures that can help lengthen the penis. In one such method, doctors can cut the ligament at the base of the penis and implant a silicone spacer between the erectile tissue of the penis and the public bone. This method can extend penile length by about 2 cm, leading to good long-term outcomes and patient satisfaction.
Thanks to advanced technology, it’s rare for the device inserted during penile prosthesis surgery to malfunction or not work as it should. But should this unlikely event occur, a solution might be replacing just the part of the device that is not functioning.
What Else Should I Know About Penile Prosthesis Implantation?
Penile prosthesis implantation, a surgery where a device is placed in the penis to improve erections, has proven to be a safe and effective way to manage erectile dysfunction (ED); this medical condition is when a man has difficulty getting or keeping an erection. This procedure has greatly improved the quality of life for patients who undergo it. Erectile dysfunction has been becoming more common, which means that more and more men are choosing to get penile prostheses.
In the last 50 years, this procedure has improved a lot thanks to advancements in technology. Now, the prostheses function better, last longer, look better, and are more reliable. These improvements show how important it is to continue researching and innovating in this medical field, as it allows for more improvements in penile prosthesis implantation techniques, which will benefit patients even more.
