Fundamentals of prosthetic urology.

The field of prosthetic urology demonstrates the striking impact that simple devices can have on quality of life. Penile prosthesis and artificial urinary sphincter implantation are the cornerstone procedures on which this specialty focuses. Modern research largely concentrates on decreasing the rates of complication and infection, as the current devices offer superior rates of satisfaction when revision is not necessary. These techniques are also able to salvage sexual function and continence in more difficult patient populations including female-to-male transgender individuals, those with ischemic priapism, and those with erectile dysfunction and incontinence secondary to prostatectomy. This review summarizes modern techniques, outcomes, and complications in the field of prosthetic urology.

INTRODUCTION

Prosthetic urology is a field that exhibits the true wonder of modern medicine. From those struggling with urinary incontinence being able to regain social function to the transgender person feeling more whole in their physical body, this branch of urology is ripe with achievement and room for development. This publication provides a survey of the two cornerstone procedures in the field: penile prosthesis (PP) implantation and artificial urinary sphincter (AUS) placement. Devices such as these elevate quality of life to match the increased lifespan that modern medicine affords us. For instance, the 15-year survival rate for prostate cancer across all stages is 96%; however, some estimates of erectile dysfunction (ED) after radical prostatectomy surpass 70% and rates of stress urinary incontinence (SUI) over 50%.1 Similarly, mortality for diabetes and atherosclerotic disease have been decreased by contemporary therapy, but these illnesses predispose patients to ED that may become refractory to nonsurgical treatment as vascular injury inevitably mounts. PP implantation offers both a definitive solution for recalcitrant ED and an earlier treatment option that trumps noninvasive therapy in terms of satisfaction.2

METHODS

A detailed, comprehensive literature review was performed to identify all published peer-reviewed articles which include PP and AUS in the urological literature over a 19-year period, i.e., between 2000 and 2019. The search was conducted through MEDLINE® database, the Cochrane Library®, Central Search, Web of Science, and Google Scholar. The initial search terms were PP and AUS. Search results were screened for appropriate studies with particular emphasis placed on clinical and experimental studies as well as review articles. Articles referenced were screened to maximize review and inclusion of pertinent data. While English-language text was not a specific search parameter, only English-language publications were considered. All relevant studies collected were carefully examined to extract relevant data pertaining to PP and AUS.

Past, present, and future development of penile prosthesis implantation

Penile implants have evolved from the earliest days of using prosthetic material to salvage quality of life, into the most effective treatment of ED. Although Ambroise Paré fashioned a wooden phallus for soldiers affected by penile trauma in the 1500s, his device was only designed to aid in urination in a standing position.3 The first prosthetic created for urinary and sexual function was made of rib cartilage and designed by Nikolaj A Bogoraz in 1936.3 Years of experimentation with other materials lead to F Brantley Scott's development of the ancestor to modern inflatable penile prostheses in 1973.3 Once the pattern of inserting prosthetic material into the corpora cavernosa was established as an effective technique, the modern era of PP implantation emerged.3

Today's penile prostheses can largely be grouped into inflatable penile implants and semirigid devices. The most commonly implanted device in the United States is currently the three-piece inflatable penile prosthesis (IPP).4 It consists of two inflatable cylinders, a pump which is often implanted into the scrotum and a reservoir. These devices are the most commonly used because they offer optimum rigidity to perform sexual function and can deflate to a comfortable level. Drawbacks are that using the pump requires a certain amount of manual dexterity that may be difficult in those with poor sensation or motor control such as diabetics.56 The two-piece model is an IPP, which comprised only of cylinders and a pump. Two-piece IPPs make up <5% of implanted PPs, but offer simpler inflation and deflation which is beneficial to an elderly population with poor sensation.6 In addition, its lack of a reservoir makes it ideal in those with extensive abdominopelvic surgical scarring.56 Although this implant's rigidity is not as robust as that of the three-piece IPP, patients largely report that they are able to have coitus and satisfaction rates rival the three-piece IPP.5 The malleable penile prosthesis (MPP) is made up of a semirigid rod placed in the corpora cavernosa. By nature, the device is constantly rigid and can be manipulated by patients, but will never achieve a state of detumescence similar to the inflatable devices. Satisfaction rates for these devices are high (), and they are useful in salvage procedures after explanation of previously infected or damaged penile implants, which will be discussed later.78

The remarkable success of modern devices has directed research to modifying current models instead of trying to revolutionize the system.3 The current literature centers on reducing infection and complication rates which are the bane of PP implantation. There is also promising investigation in consolidating multiple operations into one procedure such as simultaneous AUS and IPP placement or radical prostatectomy and IPP implantation.9 Being able to perform both operations in one setting may decrease the rate of IPP underutilization by motivating patients who are hesitant to take multiple trips to the operating theater. There is some early development of a nickel-titanium memory alloy prosthetic by Dr. Brian Le, which changes shape based on heat; however, this project is in its infancy.10 Finally, there are reports of prosthetic urological procedures such as malleable PP implantation being performed in the office under local anesthesia as a cost-saving measure.11 This may encourage more patients to undergo PP implantation who are fearful of general anesthesia.

ED is estimated to affect 52% of men over the age of 40 years.12 It can be secondary to or exacerbated by general comorbidities such as hypertension, hyperlipidemia, and diabetes mellitus as well as other urological-related conditions such as penile trauma, Peyronie's disease, and testosterone deficiency.3 Although less invasive medical therapies dominate the market, PP implantation is the definitive treatment for erectile dysfunction.13 PP placement has not only demonstrated a higher rate of satisfaction than oral phosphodiesterase-5 inhibitors and intracorporeal injection therapy in retrospective trials, but also it is the only therapy able to treat refractory disease.14

Satisfaction rates in recent literature are summarized in . Notably, there have been multiple studies validating that penile implants are also successful in special populations such as those who have a history of radical prostatectomy, pelvic radiation and priapism as well as female-to-male transgender patients and those with a neophallus generated after trauma.15

Patients who are dissatisfied with their prostheses are made up mostly of two subpopulations. The first are those who have had complications and undergone revisions.16 Complications are examined in their own section, but infection is the most drastic and is estimated to affect 1%–4% of primary penile implantations.1617 Each complication that requires revision leads to an increased chance of additional complications as well as the risk of cavernosal fibrosis which makes future procedures more challenging and often requires smaller cylinders.7 The second group of patients more likely to be dissatisfied are summarized by the characteristics described in the mnemonic “CURSED” by Trost et al.18 in 2013. Patients who are identified as being “Compulsive/obsessive, Unrealistic, Revision, Surgeon Shopping, Entitled, Denial, or Psychiatric” are more inclined to have lower satisfaction rates.18 These patients should be managed by discussing clear expectations of outcomes and complication rates.218

Even including these subpopulations, PP implantation is a successful procedure that is underutilized. Less than 5% of those eligible for PP implantation receive the surgery.10 In addition, the rates of PP insertion in the United States fell from 4.6% to 2.3% of eligible patients from 2002 to 2010.19 Theories explaining low implantation rates include lack of advertising and patient education as well as increased use of medical therapy. Cost effectiveness is a factor that varies considerably based on the health system. In any case, work should be done to expand the reach of penile implantation, which is the gold standard of ED treatment.19

Modern techniques in penile prosthesis implantation

IPPs are by far the most used penile prostheses. The two main surgical approaches are via penoscrotal or infrapubic incisions.20 Both techniques have been examined by multiple recent studies that have demonstrated that neither is clearly superior, but each method has distinct advantages.202122 The penoscrotal approach provides better corporal exposure, less risk of damage to dorsal nerves especially during revisions, and the ability to place the pump directly into the scrotum and is easier accomplished in obese patients.2021 Drawbacks include blind placement of the reservoir and risk of urethral damage.21 The infrapubic approach can be accomplished faster, provides visualization of the reservoir during placement, and is simpler to perform in those with previous pelvic surgery.2022 Cons include theoretical risk of dorsal nerve damage as well as more difficult scrotal pump placement.22

Reservoir placement can also be accomplished via varying methods. Conventionally, it was placed in the space of Retzius; however, this can be problematic in patients with previous pelvic surgery, so ectopic placement has been more commonly accepted.2324 The submuscular placement of the reservoir places it between the transversalis fascia posteriorly and the abdominal musculature anteriorly.24 The traditional placement has a risk of damage to the bladder and other pelvic vasculature; however, this is rarely reported in the literature.23 The submuscular approach is easier to accomplish in patients with previous pelvic surgery, but has a higher rate of herniation than placement into the space of Retzius.24

Penile prosthesis implantation complications

Although there is measurable evidence that penile shortening does not occur postuncomplicated PP implantation, over 70% of men report this phenomenon, making it the most commonly cited cause of dissatisfaction.16 The least invasive way to address this is to set reasonable expectations including preoperative measurement of stretched flaccid penile length which best approximates postoperative results.25 More intensive ways of length preservation have been offered to men who have risk factors for penile shortening such as those undergoing revision surgery or patients who have undergone prostatectomy. These methods include preoperative use of vacuum or penile traction devices which can allow larger cylinders to be implanted.26 Surgical techniques to reduce the appearance of penile shortening include the modified sliding technique which involves making a dorsal and ventral incision on the tunica albuginea and using a larger cylinder, thereby extending the penis and leaving a defect in the tunica.27 This procedure carries the risk of glans necrosis, which is catastrophic, so it should be used in select cases by experienced surgeons. However, the technique was successfully performed by Egydio et al.27 and resulted in an average of 3.1 cm in penile length without a significant increase in infection. Another approach includes simultaneous suprapubic lipectomy which results in a gain of 3.72 cm on average from preoperative stretched length without an increase in the rate of infection or complication.28 A major caveat is that this study was carried out by high-volume urologists, and the theoretical risk of infection in less experienced hands may necessitate a staged approach.

Infection is the most feared complication of PP implantation because it often leads to explantation, which can result in penile shortening and cavernosal fibrosis.1629 Furthermore, each revision increases the risk of additional infection and complication due to a more hostile surgical environment and potentially from remnants of a previous bacterial biofilm.216 As stated earlier, the risk of infection in PP implantation is estimated at 1%–4% in virgin cases.16 Factors that have been demonstrated to increase the risk of infection are smoking, revision surgery, poorly controlled diabetes mellitus (hemoglobin A1c >11.5%), and spinal cord injury.16303132 Modifiable risk factors should be controlled preoperatively. Methods demonstrated to reduce the risk of infection include the “no skin touch” technique which involves changing surgical gloves and considering all surgical equipment contaminated after the initial incision is made and then using a barrier to prevent contact between anything with the skin until surgical closure.33 This method was shown to decrease infection rates of a particular surgeon from 1.99% to 0.44% with only 15 min of additional operative time.33 Perioperative antibiotics are recommended to further reduce infection risk.34

Mulcahy described a salvage technique for infected PP in 1996.16 It involves removing the device completely performing multiple different antiseptic lavages, followed by resterilization by changing gowns, drapes, and instruments and reimplantation of another device.17 This procedure has a reported success rate of 84%.16 However, those with an infection that compromises scrotal tissue are not candidates for immediate placement of IPP, so the malleable implant salvage technique was introduced in 2009.7 This procedure is similar to the one mentioned above, but instead implants an MPP which serves as either a permanent replacement or a bridge to future IPP implantation. Immediate MPP placement is done to prevent extensive corporal fibrosis. This procedure has a success rate of over 90%.7 Reimplantation of an IPP in a severely fibrotic corpus is a technical challenge that may require special instrumentation such as Carrion–Rosello device or Mooreville dilator which facilitate space for the placement of the new prosthetic device.1735 Preoperative vacuum rehabilitation regimens are another strategy for reimplantation in hostile corpora.17

Erosion is another devastating complication of penile prosthesis and occurs in an estimated 1%–6% of cases.17 It is more likely to occur if the urethra is damaged intraoperatively and in spinal cord injury patients who require intermittent catheterization.16 Although erosion into the urethra is a feared complication, it can also affect the lateral aspect of the corpora, the glans, and other surrounding structures. If there is suspicion that cylinders in the process of eroding are infected, they should be explanted.16 Ventrolateral and ventromedial erosion can be salvaged by Mulcahy's (natural tissue repair) corporoplasty which creates a space to position a new device more medially than the previously eroded one.16 Erosion of the device into the urethra is covered below in the urethral injury section.

Corporal perforation and crossover are occurrences that are more common in fibrotic corpora. In fact, a 31% proximal perforation rate and 25% distal perforation rate was reported in a series of IPP implantations placed in fibrotic corpora.16 These complications are often detected when loss of resistance is felt during dilation of the proximal corpora and can be confirmed by comparing the measurements of dilators inserted in both corpora.1617 A difference >1 cm indicates probable proximal perforation.16 Proximal corporal perforation can be surgically corrected by placing corporotomy sutures around the outlet tubing and using a rear tip extender sling or windsock patch to prevent migration.16 The unaffected corpora should be used to size the implant. Distal perforations are more grievous because they risk urethral injury. Irrigating the affected corpora while watching for leakage around the urinary meatus should be performed.16 If a distal perforation occurs during the first cylinder's insertion, the operation is aborted and attempted later; however, if it occurs during the placement of the second cylinder, the first can be left in place and the removed cylinder side tubing capped to provide the patient with some rigidity.1617 The explanted side can be reinserted 3–6 months later if the patient desires. If a cylinder perforates in a manner that exposes it to the outside environment, it should be considered contaminated and managed accordingly.16

Urethral injury occurs in 1%–3% of PP of virgin implantations and can occur intraoperatively or secondary to erosion, which presents in a delayed fashion.36 Dense corporal scarring and penile modeling in Peyronie's disease patients are risk factors for intraoperative urethral injury.36 71.1% of reported intraoperative urethral injuries are due to distal corporal perforations during dilation.3738 Urethral injury can be avoided during dilation by always proceeding cautiously in a lateral direction.36 As mentioned earlier, corporal irrigation revealing leakage at the urinary meatus confirms urethral perforation.16 Expert opinion advises aborting the operation if this complication occurs while inserting the first cylinder and leaving the first cylinder in if it occurs during the second cylinder's implantation.1636 There are case reports of implanting both cylinders successfully after primary urethral repair, but this is at the hands of a high-volume surgeon.38 Very minor distal injuries can be managed by leaving a Foley catheter in place and monitoring for a few days.36 Other more severe injuries necessitate urethroplasty that could require multiple revisions to complete the urethral repair and PP implantation.38 Urethral erosion from PP presents in a delayed fashion and extravasation of urine into the corpora can cause pain and risk of infection.1638 This type of perforation requires washout and often delayed prosthetic replacement to allow for urethral repair and recovery.36

Penile prostheses are very reliable with mechanical survival rates of 78%–100% at 5 years across devices.2 Although autoinflation of three-piece penile implants occurred in the past, the introduction of lockout valves has mitigated this problem.39 Reservoir migration is possible and there are a few documented cases of submuscularly placed reservoirs entering the peritoneum, but all were repaired without complication.40 A case series reported difficulty in cycling the three-piece IPPs after weeks of disuse. This problem was previously managed by replacing the device; however, recent literature has demonstrated that the issue can be resolved by forced deflation and cycling in the office.39 There is theoretical risk of bladder, bowel, and vascular damage during placement or removal of the reservoir from the space of Retzius.23 A retrospective review of 400 cases only identified six reservoir-related complications, making this an uncommon problem, but damage to branches of the external iliac artery, bladder, or bowel can be disastrous, so care should be taken especially during revision surgery when approaching the reservoir.41

Hypermobility of the glans penis is a rare complication that is also known as the supersonic transporter (SST) deformity due to the ventrally drooping glans appearing similar to the dipping nose of a Supersonic Concorde jet. It can lead to difficulty or discomfort during intercourse, increasing the rates of dissatisfaction.42 Previously thought to be due to undersized cylinders, it is now believed that a number of other comorbidities can cause this issue due to inadequate glanular support despite proper sizing.43 Risk factors include fibrotic corpora, uncontrolled diabetes, previous penile surgery, androgen deprivation therapy, and priapism.43 Repair of this deformity can be performed postoperatively or intraoperatively if hypermobility is noticed after cylinder inflation.43 Ziegelmann et al.43 characterized the Modified Glanulopexy Technique in 2018, which uses sutures to anchor the glans to the corpora and provides a more ergonomic angle between the glans and the penile shaft which prevents dyspareunia.

Recent literature has identified proximal corporal deformities which may lead to devices that can be cycled but are wobbly and unstable leading to difficulty with use.44 These patients were treated with proximal corporoplasty and reimplantation with a prosthetic device. Subsequently, all recorded cases reported greater penile stability and satisfactory sexual intercourse.44

Past, present, and future development of artificial urinary sphincter implantation

Urinary incontinence is a condition that dramatically decreases the quality of life. As mentioned previously, the oldest documented penile prosthetic, Ambroise Paré's 16th century wooden phallus, was used for micturition.3 Wilhelm Fabricius Hildanus followed in the 1600s by creating a penile clamp to manage stress urinary incontinence which inspired the creation of a bulbar urethral compression belt in 1747 by Lorenz Heister.45 These devices provided the foundation for the modern AUS. Frederic Foley is credited for the first device that surrounds and compresses the corpus spongiosum in 1948 and the same Brantley Scott who developed the modern PP in 1973 also described the first multicomponent AUS in the same year.45 Today's AUSs are similar to what Scott introduced with minor cuff variations and antimicrobial covering.46

Present-day AUSs consist of a pressure-regulating balloon (PRB), pump, and a cuff. The cuff fits around the urethra and the PRB ensures that the urethra is compressed sufficiently to prevent gross urinary leakage. When the pump is triggered, liquid will flow from the cuff to the PRB allowing micturition. Finding the adequate pressure for the cuff is a balance which involves several factors. The cuff must provide enough pressure to prevent urinary leakage taking into account increases in intra-abdominal pressure during everyday activities such as lifting or straining.45 In addition, the cuff should not be inflated to the point of causing urethral erosion or be so tight that urine cannot leak out in the setting of pressures sufficient to cause ureteral or renal dilation.45 The most used devices of this era employ a PRB with a standard pressure between 61 cm and 70 cm of H2O with the activating pump device placed in the scrotum and the cuff surrounding the proximal bulbar urethra.45

Future development for AUSs includes a multitude of concepts which are being tested ex vivo. They include using shape metal alloys as a cuff, magnetic devices to deflate the cuff, and wireless communication devices for cuff deflation as well as piezoelectric and electroactive polymer components.45 These devices underscore the urge to develop a product that is more convenient to use and less likely to erode the urethra, but they are all in early stages of development or limited by factors such as high voltage or temperature inside the body.45

Successful AUS outcomes are not judged based on complete dryness, but a significant reduction in urinary leakage often measured as 0–1 pad per day. Using that scale, modern success of these devices ranges between 46% and 88.5%.47484950 When compared to other treatments for stress urinary incontinence in men, the AUS implantation is still the gold standard.48 Although slings have become more popular in the last few years, they have a lower success rate. While there are no current randomized control trials that measure AUS versus sling, 13% of men with a sling will eventually require an AUS.4748 In addition, when a sling fails which can be up to 60% of the time based on clinical literature, patients are six times more likely to be incontinent when a sling revision is performed instead of an AUS implantation.4751 Because there is no evidence that implanting an AUS in a patient status postsling procedure poses a significantly higher risk of complication or residual incontinence, the 6th International Consultation on Incontinence considers AUS implantation the definitive treatment of stress urinary incontinence in men; using a sling is an option in men with mild stress incontinence who prefer it.48

Modern outcomes for AUS are summarized in . The rates of revision oscillate widely between studies due mainly to infection or erosion. Like PP implantation, AUS placement is a definitive and effective treatment whose main drawback is the rate of revision and complication.4547

Modern techniques in artificial urinary sphincter implantation

AUSs can be implanted via a perineal or penoscrotal approach. The perineal technique was traditionally used until the penoscrotal method was introduced in 2003. The penoscrotal approach is a faster technique that only requires a single incision.5253 Since then, the rate of penoscrotal AUS placement has been increasing despite evidence that the perineal approach has superior outcomes.52 Two multicenter evaluations of these techniques revealed that the perineal approach had double the rate of effectiveness in the virgin procedure as well as lower rates of revision.52 It is hypothesized that the lower success rates in the penoscrotal approach are due to more distal cuff placement on the bulbar urethra.53 The bulbar urethra's tissue is thinner distally that may contribute to a higher rate of erosion.

Artificial urinary sphincter implantation complications

Urinary retention was found in 31% of procedures, making it the most prevalent complication identified in a 2015 retrospective review.54 Those who experience postoperative urinary retention have a higher revision rate than the average patient (76% vs 89%, P = 0.04) and a higher infection rate.54 Retention may be due to temporary bladder dysfunction from anesthesia and narcotics, so using a small caliber catheter for 24–72 h and re-evaluating is an appropriate management strategy.4954 Retention persisting longer than this may be due to transient edema or a cuff that is too tight, so revision or placement of a suprapubic catheter and revisiting in 1 month are potential strategies for evaluation.49 A recently published article claims that most patients managed with suprapubic catheter and long-term follow-up demonstrate resolution of urinary retention without AUS revision.49

Some patients may notice a slight decrease in continence over time even after successful surgery which may lead to a request for re-evaluation.54 If infection, erosion, urge incontinence, and overflow incontinence are ruled out as potential etiologies, then mechanical failure should be investigated.49 Device failure often presents as increased stress incontinence without hematuria and its onset is more rapid than urethral erosion.49 Mechanical failure can be identified by a lack of typical fullness during cycling or the sound of air in the system.49 If device failure is suspected but not apparent, then sonography or other imaging modalities can be used to visualize the devices ability to cycle. Of device malfunctions, 46% are cuff related, while 23% are due to the PRB.50 Studies have been undertaken to determine if replacing individual parts could be as effective as total device replacement, and while findings did not rise to the level of significance, replacing the entire device had a slightly higher rate of 3-year functionality (76% vs 60%, P = 0.11).55

Nonmechanical causes of loss of efficacy were previously attributed to urethral atrophy due to the appearance of device uncoupling on imaging.56 More recent literature suggests that it is more likely due to fibrotic encapsulation of the device, which can be surgically managed with capsulotomy. There is some debate as to whether entire device replacement would be more prudent in these cases due to the PRB's loss of pressure profile over time.4956

Infection is an equally grave complication as in PP implantation, but there has not been an extensive investigation of the risk factors and etiologies in this case. Infection rate has been reported as high as 7% in modern trials.57 Although negative preoperative urinary cultures are routinely advised, there is literature debating this practice.58 There is no salvage procedure described for AUS implantation, so an infected device should be removed in its entirety. Despite this, there are few published case reports of replacing single components with limited success.49

Erosion is a relatively common complication estimated to occur around 18% of procedures.59 Patients at higher risk of erosion include those with prior pelvic radiation, myocardial infarction, hypogonadism, urethroplasty, treatment for bladder neck contracture or urethral stricture, history of urethral stent, as well as prior infected or eroded AUS.59 Erosion is managed by device removal and delayed reimplantation.49

CONCLUSIONS

Prosthetic urology is a surgical field that provides life-altering therapies for its patients. Devices such as IPPs and AUSs are the cornerstone of the discipline which are effective and only limited by rates of revision. Future research will be directed at lowering complication rates and optimizing their management, so that these remarkable procedures can continue to have their uses expanded.

AUTHOR CONTRIBUTIONS

KPA was responsible for data acquisition and drafting the manuscript. KPA and OAR contributed to reviewing the manuscript. Both authors read and approved the final manuscript.

COMPETING INTERESTS

Both authors declared no competing interests.

Table 1

Summary of modern penile prosthesis implantation outcomes

Author	Year	Study	Device type	Device brand	Patients (n)	Mean follow-up (month)	Infection (%)	Postoperative IIEF Score	Postoperative EDITS Score	Satisfaction (%)	Penile length change (cm)
Loh-Doyle et al.15	2018	Retrospective	IPP	AMS 700	78	49	2.6	–	–	–	–
Habous et al.60	2018	Prospective	IPP + MPP	Various (IPP; MPP)	45; 88	27.2	–	–	–	–	(+) 0.62 cm; (+) 0.22 cm
Habous et al.61	2018	Retrospective	IPP + MPP	Various	204 versus 588	–	–	–	–	76 versus 86.8	–
Morgado et al.62	2018	Retrospective	IPP	AMS 700C and Coloplast Titan	55		–	–	77.2±12.1 versus 77.5±16.6	–	–
Akdemir et al.8	2017	Retrospective	MPP	AMS Spectra	46	38.28	2.17	63	71.06	96.2	–
Bennett et al.63	2017	Retrospective	IPP + MPP	Various Ambicor devices	1255	>24	–	99	–	–	–
Gentile et al.64	2016	Retrospective	IPP	Two-piece Ambicor and Coloplast Excel	42	26.7	4.8	–	75 modified EDITs	–	–
Bozkurt et al.65	2015	Retrospective	IPP + MPP	Various (IPP; MPP)	118; 139	34; 52	–	78; 57	78; 57	–	–
Carvalheira et al.66	2015	Retrospective	IPP	Various	47	38.27	–	–	–	79	–
Falcone et al.67	2013	Prospective	MPP	AMS Spectra	22	24.3		53.9/75	45.2	86.4	–
Menard et al.68	2011	Retrospective	IPP	Various Two-Piece Devices	210	37.6	1.1	>85	–	–	–
Bettocchi et al.69	2010	Retrospective	IPP	AMS CX 700	80	–	–	–	–	90	–
Wang et al.70	2009	Prospective	IPP	AMS 700 CX and Coloplast Titan	11	12	–	–	–	–	(–) 0.74 cm
Natali et al.71	2008	Retrospective	IPP	Various	200	60	3.1	–	81/91	–	–
Lux et al.72	2007	Retrospective	IPP	Two-piece	146	38	0.7	–	88/76	–	–
Deveci et al.73	2007	Retrospective	IPP	Various	56	–	–	(+) 15.6 change	62.4	–	–
Minervini et al.74	2006	Retrospective	IPP + MPP	Various	447	50	8	–	–	81	–
Borges et al.75	2006	Retrospective	IPP	Coloplast Alpha 1	303	–	–	–	–	93	–
Mulhall et al.76	2003	Retrospective	IPP	Various	96	12	–	59/75	81/100	–	–
Rajpurkar and Dhabuwala77	2003	Prospective	IPP	Various	32	18.91	–	–	36.09	93.8	–
Levine et al.78	2001	Retrospective	IPP	Two-piece Ambicor	131	43.4	4.6	–	90.6/82.6	95.5	–
Montorsi et al.79	2000	Retrospective	IPP	AMS Three- piece	200	59	6	–	–	92	–
Carson et al.80	2000	Retrospective	IPP	AMS 700CX	372	–	3.2	–	–	86.5	–
Holloway and Farah81	1997	Retrospective	IPP	AMS 700 Ultrex	145	42	8	–	–	85	–

This table summarizes published literature on outcomes of penile implantation from 1997 to publication date. AMS: American Medical Systems; EDITS: Erectile Dysfunction Inventory of Treatment Satisfaction; IIEF: International Index of Erectile Function; IPP: inflatable penile prosthesis; MPP: malleable penile prosthesis. –: no value reported; (+): positive change in value; (-): negative change in value

Table 2

Summary of modern artificial urinary sphincter implantation outcomes

Author	Year	Study type	Device	Patients (n)	Mean follow-up (month)	Infection (%)	Continence (%)	Satisfaction (%)
Sacomani et al.82	2018	Retrospective	AMS 800	121	62.4	–	87.6	–
Serag et al.83	2018	Retrospective	AMS 800	84	39	2.4	80.7	–
Ostrowski et al.84	2018	Prospective	ZSI 375	50	21	0	58	–
Ostrowski et al.85	2017	Retrospective	ZSI 375	147	–	6.12	83.5	–
Linder et al.86	2015	Retrospective	AMS 800	1802	62.4	0.082	59	94
Leon et al.87	2015	Retrospective	AMS 800	57	180	3.51	77.19	89.5
Gulpinar et al.57	2013	Retrospective	AMS 800	56	96	7.1	46	–
Bordenave et al.88	2011	Retrospective	AMS 800	159	5.75	4.4	74.2	–
Kim et al.89	2008	Retrospective	AMS 800	124	81.6	5.64	82	–
Lai et al.90	2007	Retrospective	AMS 800	270	36	5.5	69	–
Petero and Diokno91	2006	Retrospective	AMS 800	108	97.2	1.14	62	–
Raj et al.92	2005	Retrospective	AMS 800	554	50.4	0.5	88.5	–
Venn et al.93	2000	Retrospective	AMS 800	100	132	37	84	–
Gousse et al.94	2001	Retrospective	AMS 800	131	92.4	1.4	59	77
Montague et al.95	2001	Retrospective	AMS 800	209	61.2	–	64	–
Elliott et al.96	1998	Retrospective	AMS 800	323	68.4	1.75	–	–
Klijn et al.97	1998	Retrospective	AMS 800	27	35	–	81	–
Haab et al.98	1997	Retrospective	AMS 800	68	86.4	–	80	3.9/5 scale
Fulford et al.99	1997	Retrospective	AMS 800	68	120	–	61

This table summarizes artificial urinary sphincter outcomes from 1997 to publication date. AMS: American Medical Systems; ZSI: Zephyr Surgical Implants. –: no value reported