Penile Implant Instrument Innovations.

PURPOSE OF REVIEW: Numerous innovations have been made since the first inflatable penile prosthesis was introduced in 1973-not just of the implant apparatus itself, but crucially also in the surgical instruments used for prosthetic surgery. Starting with Dr. Furlow's revolutionary inserter tool, advancements were quickly made in dilators, retractors, and cavernotomes. RECENT FINDINGS: More recent innovations have been made in inserter tools, forceps, needle holders, clamps, and disposable instruments. Leading companies Boston Scientific and Coloplast have contributed significantly to the evolution of IPP surgical placement, and companies such as Uramix and Rigicon are developing a wide array of new specialized tools. We aim to summarize the instruments needed for IPP placement, with a focus on describing the variety of instrument innovations since Dr. Brantley Scott designed and placed the first IPP.

Extended Reality-Assisted Surgery as a Surgical Training Tool: Pilot Study Presenting First HoloLens-Assisted Complex Penile Revision Surgery.

BACKGROUND: Extended reality-assisted urologic surgery (XRAS) is a novel technology that superimposes a computer-generated image on the physician's field to integrate common elements of the surgical process in more advanced detail. An extended reality (XR) interface is generated using optical head-mounted display (OHMD) devices. AIM: To present the first case of HoloLens-assisted complex penile revision surgery. METHODS: We describe our pilot study of HoloLens-assisted penile revision surgery and present a thorough review of the literature regarding XRAS technology and innovative OHMD devices. OUTCOMES: The ability of XRAS technology to superimpose a computer-generated image of the patient and integrate common elements of the surgical planning process with long-distance experts. RESULTS: XRAS is a feasible technology for application in complex penile surgical planning processes. CLINICAL TRANSLATION: XRAS and OHMD devices are novel technologies applicable to urological surgical training and planning. STRENGTHS AND LIMITATIONS: Evidence suggests that the potential use of OHMD devices is safe and beneficial for surgeons. We intend to pioneer HoloLens technology in the surgical planning process of a malfunctioning penile implant due to herniation of the cylinder. This novel technology has not been used in prosthetic surgery, and current data about XRAS are limited. CONCLUSION: OHMD devices are effective in the operative setting. Herein, we successfully demonstrated the integration of Microsoft HoloLens 2 into a penile surgical planning process for the first time. Further development and studies for this technology are necessary to better characterize the XRAS as a training and surgical planning tool. Quesada-Olarte J, Carrion RE, Fernandez-Crespo R, et al. Extended Reality-Assisted Surgery as a Surgical Training Tool: Pilot Study Presenting First HoloLens-Assisted Complex Penile Revision Surgery. J Sex Med 2022;19:1580-1586.

Distal Biologic Cap for Impending Distal Erosion.

INTRODUCTION: Management for distal impending erosion can be difficult and has been previously managed with counter incisions which can lead to unsightly scars and increased infection risk. AIM: To demonstrate a novel technique in management of impending erosion. METHODS: We retrospectively reviewed patients who underwent placement of a distal biologic cap for impending erosion. MAIN OUTCOME MEASURE: The main outcome was thesuccessful placement of inflatable penile prosthesis through a single incision. RESULTS: All patients who underwent this procedure are functional and have had no evidence of recurrence. CLINICAL IMPLICATIONS: A simple approach to manage impending distal erosion. STRENGTH & LIMITATIONS: Limitations include small sample size and short duration of follow-up. CONCLUSION: The distal biologic cap is a simple alternative technique to treat distal impending erosion of an inflatable penile prosthesis and can be performed safely without the need for additional incisions on the penis and with a minimal increase in operative times. Karpman E, DiGiorgio L, Carrion RE. Distal Biologic Cap for Impending Distal Erosion. J Sex Med 2020;17:551-555.

Suprapubic Fat Pad Excision with Simultaneous Placement of Inflatable Penile Prosthesis.

INTRODUCTION: Many men suffering from erectile dysfunction are overweight with generous suprapubic fat pads, which often contribute to a decrease in visible exophytic phallic length. AIM: To present a novel surgical concept of suprapubic fat pad excision with a concomitant placement of inflatable penile prosthesis. METHODS: A transverse incision begins slightly medial to the anterior superior iliac spine, with the superior edge crossing transversely to the contralateral anterior superior iliac spine. The inferior border is incised in a curvilinear fashion, with the medial apex being approximately 1 cm above the base of the penis. Dissection is carried down to the lower abdominal anterior fascia, which leads to excision of the suprapubic fat pad. Using this same exposure, the inflatable penile prosthesis (IPP) is placed via an infrapubic approach. The wound is reapproximated in multiple layers, and 2 drains are placed, 1 subcutaneous in the area of the fat pad excision and the other in the scrotum around the pump. MAIN OUTCOME MEASURES: Primary outcomes included penile implant functionality, ability to engage in sexual activity, and cosmetic satisfaction. RESULTS: A total of 8 patients have undergone suprapubic fat pad excision with simultaneous placement of IPP at our institution. Average body mass index of our patient cohort was 36.6. 1 patient developed prosthetic infection after inadvertent removal of his drains in the immediate postoperative period. At last follow-up, all other patients have excellent cosmetic and functional outcomes. CLINICAL IMPLICATIONS: This technique can lead to higher patient satisfaction with their penile implant, enhanced sexual performance, and improved quality of life for patients with concurrent erectile dysfunction and significant suprapubic fat pad. STRENGTHS & LIMITATIONS: This unique technique has never been previously described. It allows placement of IPP in the setting of fat pad excision without any additional incisions. Limitations include the small patient population and relatively short follow-up. CONCLUSIONS: Suprapubic fat pad excision is a safe and reproducible technique that can be performed simultaneously with the placement of an IPP in appropriately selected patients. Patients must be counseled appropriately on the expectations of surgeries and the theoretical increased risk of postoperative complications, such as infection. Baumgarten AS, Beilan JA, Shah BB, et al. Suprapubic Fat Pad Excision with Simultaneous Placement of Inflatable Penile Prosthesis J Sex Med 2019;16:333-337.

Multicenter Investigation of Fungal Infections of Inflatable Penile Prostheses.

BACKGROUND: Fungal infections of inflatable penile prostheses (IPPs) are inadequately understood in the literature. AIM: To review a multi-institution database of IPP infections to examine for common patient and surgical factors related to IPP fungal infections. METHODS: This is a retrospective Institutional Review Board-approved analysis of 217 patients at 26 institutions who underwent salvage or device explant between 2001 and 2018. Patient data were compiled after an extensive record review. OUTCOMES: 26 patients (12%) with fungal infections were identified. RESULTS: 23 of 26 patients (83%) with a fungal IPP infection were either diabetic or overweight. 15 patients had undergone primary IPP implantation, and the other 11 had previously undergone an average of 1.7 IPP-related surgeries (range 1-3; median 2). The average age at implantation was 63 years (range 31-92; median 63). 18 of the 26 patients with fungal infection had diabetes (69%), with a mean hemoglobin A1c (HbA1c) value of 8.4 (range 5.8-13.3; median 7.5). Twenty-two patients (85%) were overweight or obese. The mean body mass index for all patients was 30.1 kg/m2 (range 23.7-45 kg/m2; median 28.4 kg/m2), and that for diabetic patients was 30.8 kg/m2 (range 24.1-45 kg/m2, median 29.7 kg/m2). Ninety-one percent of implants were placed with intravenous antibiotics, consistent with current American Urological Association guidelines: an aminoglycoside plus first- or second-generation cephalosporin or vancomycin or ampicillin/sulbactam or piperacillin/tazobactam. 65% (17 of 26) of infected IPPs had only fungal growth in culture. No patient had concomitant immunosuppressive disease or recent antibiotic exposure before IPP implantation. CLINICAL IMPLICATIONS: More than two-thirds of the fungal infections occurred in diabetic patients and 85% occurred in overweight or obese patients, suggesting that antifungal prophylaxis may be appropriate in these patients. STRENGTHS & LIMITATIONS: This is the largest series of fungal infections reported to date in the penile prosthesis literature. The overall number of such cases, however, remains small. CONCLUSION: Fungal infections represent 12% of all penile prosthesis infections in our series and were seen mostly in diabetic or overweight patients, who may benefit from antifungal prophylaxis. Gross MS, Reinstatler L, Henry GD, et al. Multicenter Investigation of Fungal Infections of Inflatable Penile Prostheses. J Sex Med 2019;16:1100-1105.

Biomechanical Comparison of Inflatable Penile Implants: A Cadaveric Pilot Study.

BACKGROUND: Throughout the last decade there has been a growing interest in the biomechanical differences between inflatable penile prostheses (IPPs) and their significance with regard to the patient experience. AIM: To present our findings assessing the biomechanical properties of IPPs with and without rear tip extenders (RTEs). METHODS: This is a biomechanical study of the 3 most commonly used IPPs (AMS CX, AMS LGX, and Coloplast Titan) as assessed by column compression, modified cantilever deflection, and 3-point bending methods. The IPPs were surgically placed into 3 fresh cadavers via an infrapubic technique by a single large-volume implanter. A biomechanical evaluation of the properties of each IPP inside the fibroelastic tunica albuginea was assessed in blinded testing, and analyses were based on industry standard methods for assessment. OUTCOMES: Maximum axial load; kink formation; horizontal stiffness; and resistance to 3-point flexure testing were measured. RESULTS: At maximum inflation, all 3 implants had similar performance. Differences appear to be most affected by fill pressures. In fact, only the AMS LGX at less than maximum inflation (LTMI) was unable to consistently withstand the roughly 0.9 kg (2 lbs) of pressure for column load testing mimicking vaginal intromission. The Coloplast Titan showed slightly better rigidity than the AMS LGX and CX devices in horizontal load testing, and, with 3-point flexure testing, the CX showed the best rigidity in the shortest phallus (A). Overall, the Titan showed slightly better rigidity in the longest phallus (C) and the phallus with mild Peyronie's disease (B). CLINICAL TRANSLATIONS: Penile implants with circumferential expansion had higher rigidity on biomechanical testing and should be considered in a patient's decision during selection of a penile implant. STRENGTHS AND LIMITATIONS: Strengths include blinding of the biomechanical testing and analyses, surgical procedures performed by a highly experienced surgeon, and that this is the "closest to" in vivo evaluation (inside the tunica albuginea) of penile implant function and properties to date. Weaknesses are that this study was performed in cadavers and not in live patients. It also has a small sample size, including the use of only 3 cadavers, and there was no correlation of performance to patient satisfaction. CONCLUSION: The results of this study support the conclusion that all devices are capable of functionally restoring erectile capacity. However, we observed that, in general, the 2 circumferentially expanding penile prosthesis showed greater resistance in biomechanical testing when compared with longitudinal and circumferential expanding devices. This should be considered as a guide during device selection for a patient undergoing penile prosthesis. Wallen JJ, Barrera EV, Ge L, et al. Biomechanical Comparison of Inflatable Penile Implants: A Cadaveric Pilot Study. J Sex Med 2018;15:1034-1040.

Multicenter Investigation of the Micro-Organisms Involved in Penile Prosthesis Infection: An Analysis of the Efficacy of the AUA and EAU Guidelines for Penile Prosthesis Prophylaxis.

INTRODUCTION: Penile prosthesis infections remain challenging despite advancements in surgical technique, device improvements, and adoption of antibiotic prophylaxis guidelines. AIM: To investigate penile prosthesis infection microbiology to consider which changes in practice could decrease infection rates, to evaluate current antibiotic prophylaxis guidelines, and to develop a proposed algorithm for penile prosthesis infections. METHODS: This retrospective institutional review board-exempt multi-institutional study from 25 centers reviewed intraoperative cultures obtained at explantation or Mulcahy salvage of infected three-piece inflatable penile prostheses (IPPs). Antibiotic usage was recorded at implantation, admission for infection, and explantation or salvage surgery. Cultures were obtained from purulent material in the implant space and from the biofilm on the device. MAIN OUTCOME MEASURES: Intraoperative culture data from infected IPPs. RESULTS: Two hundred twenty-seven intraoperative cultures (2002-2016) were obtained at salvage or explantation. No culture growth occurred in 33% of cases and gram-positive and gram-negative organisms were found in 73% and 39% of positive cultures, respectively. Candida species (11.1%), anaerobes (10.5%) and methicillin-resistant Staphylococcus aureus (9.2%) constituted nearly one third of 153 positive cultures. Multi-organism infections occurred in 25% of positive cultures. Antibiotic regimens at initial implantation were generally consistent with American Urological Association (AUA) and European Association of Urology (EAU) guidelines. However, the micro-organisms identified in this study were covered by these guidelines in only 62% to 86% of cases. Antibiotic selection at admissions for infection and salvage or explantation varied widely compared with those at IPP implantation. CONCLUSION: This study documents a high incidence of anaerobic, Candida, and methicillin-resistant S aureus infections. In addition, approximately one third of infected penile prosthesis cases had negative cultures. Micro-organisms identified in this study were not covered by the AUA and EAU antibiotic guidelines in at least 14% to 38% of cases. These findings suggest broadening antibiotic prophylaxis guidelines and creating a management algorithm for IPP infections might lower infection rates and improve salvage success. Gross MS, Phillips EA, Carrasquillo RJ, et al. Multicenter Investigation of the Micro-Organisms Involved in Penile Prosthesis Infection: An Analysis of the Efficacy of the AUA and EAU Guidelines for Penile Prosthesis Prophylaxis. J Sex Med 2017;14:455-463.

Longitudinal and Horizontal Load Testing of Inflatable Penile Implant Cylinders of Two Manufacturers: An Ex Vivo Demonstration of Inflated Rigidity.

INTRODUCTION: Since the inception of the inflatable penile prosthesis, a new era has been ushered in for the management of erectile dysfunction. Despite multiple innovations to improve function and reliability, there are no current data comparing the biomechanical properties of these devices. AIM: To compare the resistance of the Coloplast Titan (Minneapolis, MN, USA) with that of the AMS 700 LGX (Minnetonka, MN, USA) penile prosthesis cylinders to longitudinal (penetration) and horizontal (gravity) forces. METHODS: We compared two cylinder sizes from each company: the Coloplast Titan (18 and 22 cm) and the AMS 700 LGX (18 and 21 cm). To evaluate axial rigidity, which simulates forces during penetration, we performed a longitudinal load compression test to determine the load required to cause the cylinder to kink. To test horizontal rigidity, which simulates the horizontal forces exerted by gravity, we performed a modified cantilever test and measured the degrees of bend for each device. All devices were tested at 10, 15, and 20 PSI to simulate in vivo pressures. MAIN OUTCOME MEASURES: The main outcome measurement for the longitudinal load test (penetration) was the force required for the inflated cylinder to bend, thereby affecting its rigidity. The main outcome for the horizontal rigidity test (gravity) was the angle of displacement, in which a smaller angle represents a more horizontally rigid device. RESULTS: Longitudinal column testing (penetration) demonstrated that less force was required for the AMS device to kink compared with the Coloplast implant across all three fill pressures tested. The Coloplast Titan also had a smaller angle of displacement at the modified cantilever test (gravity) compared with the AMS implant across all fill pressures. CONCLUSION: The Coloplast Titan demonstrated greater resistance to longitudinal (penetration) and horizontal (gravity) forces in this study. The AMS device was very sensitive to fill pressures. In contrast, the Coloplast Titan's ability to resist these forces was less dependent on the device fill pressure.

Partial Priapism Treated with Pentoxifylline.

MAIN FINDINGS: A 26-year-old man suffering from partial priapism was successfully treated with a regimen including pentoxifylline, a nonspecific phosphodiesterase inhibitor that is often used to conservatively treat Peyronie's disease. CASE HYPOTHESIS: Partial priapism is an extremely rare urological condition that is characterized by thrombosis within the proximal segment of a single corpus cavernosum. There have only been 36 reported cases to date. Although several factors have been associated with this unusual disorder, such as trauma or bicycle riding, the etiology is still not completely understood. Treatment is usually conservative and consists of a non-steroidal anti-inflammatory and anti-thrombotic. Promising future implications: This case report supports the utilization of pentoxifylline in patients with partial priapism due to its anti-fibrogenic and anti-thrombotic properties.

Reduction corporoplasty.

OBJECTIVE: Here we present the first video demonstration of reduction corporoplasty in the management of phallic disfigurement in a 17 year old man with a history sickle cell disease and priapism. INTRODUCTION: Surgical management of aneurysmal dilation of the corpora has yet to be defined in the literature. MATERIALS AND METHODS: We preformed bilateral elliptical incisions over the lateral corpora as management of aneurysmal dilation of the corpora to correct phallic disfigurement. RESULTS: The patient tolerated the procedure well and has resolution of his corporal disfigurement. CONCLUSIONS: Reduction corporoplasty using bilateral lateral elliptical incisions in the management of aneurysmal dilation of the corpora is a safe an feasible operation in the management of phallic disfigurement.

Tips and tricks of inflatable penile prosthesis reservoir placement: a case presentation and discussion.

INTRODUCTION: There have been many advances in the inflatable penile prosthesis (IPP) since the 1970s. While these devices were initially fraught with mechanical malfunction, the most recent models prove to be much more reliable. Although reservoir complications are not common, when they do occur, it typically involves damage to the surrounding tissues. The ability to recognize and treat these complications is paramount for any surgeon that routinely places IPPs. AIM: The aim of this article was to present a unique reservoir-related complication as well as perform a literature review of reservoir-related complications and techniques for reservoir placement, and provide a summary of dimensions and technical aspects of commonly used reservoirs. METHODS: We reviewed a unique reservoir-related complication that presented to our institution with urinary retention and constipation. We also reviewed reservoir-related complications since 1984, reviewed the most recent surgical techniques involved in reservoir placement, and summarized the dimensions and technical characteristics of both the American Medical System and Coloplast reservoirs. MAIN OUTCOME MEASURE: A reservoir-related complication that resulted in urinary retention and constipation is the main outcome measure. RESULTS: Although uncommon, reservoir complications do occur. The most common case report complication in the published literature is bladder erosion followed by external iliac compression, ileal conduit erosion, and small bowel obstruction. The case that presented at our institution was the result of a reservoir that was improperly placed in the perineum, causing urinary retention and constipation due to the compression of the bulbar urethra and rectum. CONCLUSIONS: In this era, mechanical failures of IPP reservoirs are rare as most complications occur due to damage of the surrounding tissues. Prevention, diagnosis, and treatment of these complications are important for any surgeon that implants IPPs.

Penile artery shunt syndrome: a novel cause of erectile dysfunction after penile revascularization surgery.

INTRODUCTION: Penile revascularization is a surgical treatment option for erectile dysfunction (ED) in healthy individuals due to a focal arterial occlusion in the absence of generalized vascular disease. Most described failures have been attributed to graft stenosis or disruption of the anastomosis. AIM: We report a novel phenomenon called Penile Artery Shunt Syndrome that contributed to persistent ED in a patient after penile microvascular arterial bypass surgery. METHODS: A 26-year-old man presented for evaluation of long-standing ED, which was attributed to trauma sustained 12 years earlier. He had difficulty obtaining and maintaining erections despite oral pharmacotherapy. Clinical data related to the case were studied, analyzed, and reviewed with urologic and radiologic specialists at multiple centers that collaborated in the care of this patient. MAIN OUTCOME MEASURES: Penile duplex ultrasound peak systolic velocities and five-item International Index for Erectile Function questionnaire scores were the main outcome measures. RESULTS: Initial diagnostic workup of the patient confirmed severe insufficiency of the left cavernosal artery, with no evidence of venous leak. The patient underwent penile microvascular arterial bypass surgery with anastomosis of the left inferior epigastric artery to the left dorsal penile artery. The patient had persistence of severe ED despite patent anastomosis by penile duplex ultrasound. Subsequent arteriography revealed an arterial shunt due to an aberrant obturator artery arising from the donor inferior epigastric artery. The patient underwent embolization of the aberrant obturator artery, with resolution of the shunt and marked improvement in erectile function. CONCLUSIONS: The presence of an aberrant obturator artery arising from the inferior epigastric artery may predispose to persistent ED after revascularization due to the creation of a shunt phenomenon. Pelvic arteriography may be useful in identifying anomalous anatomic considerations prior to penile revascularization and to evaluate patients with persistent postoperative ED.

Penile rehabilitation: the evolutionary concept in the management of erectile dysfunction.

A compromise in erectile function is commonly experienced after radical prostatectomy and has been attributed to injury to vascular, neurogenic, and smooth muscle. The concept of rehabilitation after organ injury is not a novel concept and is one that has been applied to all aspects of medicine. Penile rehabilitation has been classically defined as the use of a device or pharmacologic agent to aid erectile function recovery after radical prostatectomy. Here we redefine penile rehabilitation as the use of any device, medication, or intervention to promote male sexual function as a primer before and after any insult to the penile erectile physiologic axis. We also review the epidemiology, rational and current literature on penile rehabilitation after prostatectomy.

Optimizing penile length in patients undergoing partial penectomy for penile cancer: novel application of the ventral phalloplasty oncoplastic technique.

The ventral phalloplasty (VP) has been well described in modern day penile prosthesis surgery. The main objectives of this maneuver are to increase perceived length and patient satisfaction and to counteract the natural 1-2 cm average loss in length when performing implantation of an inflatable penile prosthesis. Similarly, this video represents a new adaptation for partial penectomy patients. One can only hope that the addition of the VP for partial penectomy patients with good erectile function will increase their quality of life. The patient in this video is a 56-year-old male who presented with a 4.0x3.5x1.0 cm, pathologic stage T2 squamous cell carcinoma of the glans penis. After partial penectomy with VP and inguinal lymph node dissection, pathological specimen revealed negative margins, 3/5 right superficial nodes and 1/5 left superficial nodes positive for malignancy. The patient has been recommended post-operative systemic chemotherapy (with external beam radiotherapy) based on the multiple node positivity and presence of extranodal extension. The patient's pre-operative penile length was 9.5 cm, and after partial penectomy with VP, penile length is 7 cm.

A single-institution experience with metallic ureteral stents: a cost-effective method of managing deficiencies in ureteral drainage.

INTRODUCTION: The limitations of traditional ureteral stents in patients with deficiencies in ureteral drainage have resulted in frequent stent exchanges. The implementation of metallic stents was introduced to improve the patency rates of patients with chronic upper urinary tract obstruction, obviating the need for frequent stent exchanges. We report our clinical experiences with the use of metallic ureteral stents in the management of poor ureteral drainage. MATERIALS AND METHODS: Fifty patients underwent metallic ureteral stent placement from 2009 to 2012. Stent failure was defined as an unplanned stent exchange, need for nephrostomy tube placement, increasing hydronephrosis with stent in place, or an elevation in serum creatinine. Stent life was analyzed using the Kaplan-Meier methodology, as this was a time dependent continuous variable. A cost analysis was similarly conducted. RESULTS: A total of 97 metallic stents were placed among our cohort of patients: 63 in cases of malignant obstruction, 33 in the setting of cutaneous ureterostomies, and 1 in an ileal conduit urinary diversion. Overall, stent failure occurred in 8.2% of the stents placed. Median stent life was 288.4 days (95% CI: 277.4-321.2 days). The estimated annual cost for traditional polymer stents (exchanged every 90 days) was $9,648-$13,128, while the estimated cost for metallic stents was $4,211-$5,313. CONCLUSION: Our results indicate that metallic ureteral stent placement is a technically feasible procedure with minimal complications and is well tolerated among patients. Metallic stents can be left in situ for longer durations and provide a significant financial benefit when compared to traditional polymer stents.

Ventral phalloplasty.

PURPOSE: To present the surgical technique of ventral phalloplasty as an adjunct procedure to the classic prosthetic surgery. MATERIALS AND METHODS: In this video we demonstrate how to perform a ventral phalloplasty in a patient that has undergone a penile prosthesis implantation. Our technique consists of: delineation of the penile scrotal web, excision of this redundant skin, and re-approximation of the wound to mimic the natural median raphe. RESULTS: The ventral phalloplasty improves the perception of phallic length, as well as patients' satisfaction after prosthetic surgery. CONCLUSION: Penile length perception is the main concern of patients that have undergone penile prosthesis implantation. In this video we demonstrate that the ventral phalloplasty can improve perception of phallic length, and can be an important adjunct to the classic prosthetic surgery.

Biomechanical Studies of the Inflatable Penile Prosthesis: A Review.

INTRODUCTION: The penile prosthesis remains the primary surgical treatment for refractory erectile dysfunction. Over the decades, inflatable penile prostheses' mechanical reliability, patient satisfaction, safety, and functional erectile restoration have greatly improved. During this time, many studies of biomechanical properties of the prosthesis have been conducted to better understand their biomimicry to the erect human phallus. AIM: To review all current literature on the biomechanical properties of the penile prosthesis, including prosthesis biomechanical function, and variability in model-related performance. METHODS: A Medline PubMed search was used to identify all articles of interest related to subjects involving the penile prosthesis and its related biomechanical properties. The following were included in the search for articles of interest: "biomechanics," "mechanics," "mechanical properties," "axial rigidity," "penile implant," and "penile prosthesis." Articles were further screened for content and English language. MAIN OUTCOME MEASURE: Here we perform a literature review of the bio-mechenical function, performance, and patient satisfaction of penile implants. RESULTS: Axial rigidity helps determine the ability of an erect penis to complete vaginal intromission and pelvic thrusting without buckling. Recent cadaveric data show that at maximum inflation, Coloplast and American Medical Systems (AMS) implants had comparable performance. Variability was seen at various lower fill pressures, where more severe buckling was observed. Coloplast Titan showed a tendency toward better resistance to longitudinal and horizontal forces. The AMS CX device showed similar performance to the Titan, and the AMS LGX device was shown to be most sensitive to fill pressure variation. Additionally, rear tip extenders (RTEs) appear to negatively affect axial loading, especially in settings of larger implants. CONCLUSION: Current research suggests that circumferentially expanding devices, such as AMS CX and Coloplast Titan, show better resistance to longitudinal (penetration) and horizontal (gravity) forces and, unlike the AMS LGX device, are less sensitive to device fill pressure. Additionally, RTEs have been shown to negatively impact axial loading, especially in larger cylinder inflatable penile prostheses >20 cm in length. Madiraju SK, Wallen JJ, Rydelek SP, et al. Biomechanical Studies of the Inflatable Penile Prosthesis: A Review. Sex Med Rev 2019;7:369-375.

Visualization of the neurovascular bundles and major pelvic ganglion with fluorescent tracers after penile injection in the rat.

OBJECTIVE: To evaluate whether fluorescent tracers can consistently label the neurovascular bundles (NVBs) and major pelvic ganglion (MPG) after an intracavernosal penile injection, as the reported incidence of erectile dysfunction (ED) in men after radical prostatectomy (RP) is 55-65% and thus preservation of erectile function, sparing one or both of the NVBs remains one of the most vital factors. MATERIALS AND METHODS: Male Sprague-Dawley rats (3 months old) received penile injections (20 microL; seven rats/group) of either deionized water (DW), Fluoro-Gold (FG), Fast-Blue (FB), Fluoro-Ruby (FR) or green fluorescent pseudorabies virus (GF-PRv). The rats were killed at 2, 3 and 14 days after injection and the NVBs and MPG were harvested and placed directly under fluorescence light. Image analysis was done by computer, coupled to a microscope equipped with a digital camera. Each NVB and MPG were analysed for its staining pattern and consistency. RESULTS: When compared with the FB, FR and GF-PRv rats, the FG-injected rats had better staining of the NVB at 2, 3 and 14 days after injection. Under x200, FG highlighted the axons of the cavernous nerve (CN) and cell bodies (MPG). This indicates that FG injection into the penis induced the strongest CN labelling (positive staining) at 2 and 3 days after injection as compared with FB-, FR- and GF-PRv-injected rats. CONCLUSION: FG injection into the penis has consistent retrograde staining of the NVBs and MPG after 3 days. Therefore, we predict that FG could potentially be used to improve the identification of the NVB in other models. However, further studies need to be carried out before these tracers can be used in humans.

Subarachnoid hemorrhage as complication of phenylephrine injection for the treatment of ischemic priapism in a sickle cell disease patient.

INTRODUCTION: Ischemic priapism (IP) is a urologic condition, which necessitates prompt management. Intracavernosal injection of phenylephrine is a usual treatment modality utilized for the management of these patients. Aim. We present a case of subarachnoid hemorrhage following intracavernosal injection of phenylephrine for IP in a patient with sickle cell disease. METHODS: We analyzed the degree of subarachnoid hemorrhage in our patient after intracavernosal injection of phenylephrine. The patient had an acute rise in blood pressure during corporal irrigation. This was followed by the onset of severe headache. Computed tomography (CT) scan confirmed the diagnosis of a subarachnoid hemorrhage. MAIN OUTCOME MEASURE: Subarachnoid hemorrhage associated with intracavernosal injection of phenylephrine. Result. A 23-year-old African American male with a history of sickle cell disease presented with a painful penile erection. The patient was started on intravenous fluids, oxygen by nasal canula, and analgesic medication. After this, a blood gas was obtained from his left corpora cavernosa. This was followed by normal saline irrigation and injection of phenylephrine. The patient complained of a sudden, severe "terrible headache" immediately following the last injection, and noncontrast CT scan of the head was obtained and a subarachnoid hemorrhage was noted. The patient was admitted for observation and no significant changes were noted. CONCLUSIONS: Intracavernosal injection of phenylephrine for the management of IP can be associated with several possible complications. We present our single case complicated with the formation of a subarachnoid hemorrhage. The patient was treated conservatively and had no long-term neurologic sequelae. Davila HH, Parker J, Webster JC, Lockhart JL, and Carrion RE. Subarachnoid hemorrhage as complication of phenylephrine injection for the treatment of ischemic priapism in a sickle cell disease patient.