Cellular migration into a subretinal honeycomb-shaped prosthesis for high-resolution prosthetic vision.

In patients blinded by geographic atrophy, a subretinal photovoltaic implant with 100 µm pixels provided visual acuity closely matching the pixel pitch. However, such flat bipolar pixels cannot be scaled below 75 µm, limiting the attainable visual acuity. This limitation can be overcome by shaping the electric field with 3-dimensional (3-D) electrodes. In particular, elevating the return electrode on top of the honeycomb-shaped vertical walls surrounding each pixel extends the electric field vertically and decouples its penetration into tissue from the pixel width. This approach relies on migration of the retinal cells into the honeycomb wells. Here, we demonstrate that majority of the inner retinal neurons migrate into the 25 µm deep wells, leaving the third-order neurons, such as amacrine and ganglion cells, outside. This enables selective stimulation of the second-order neurons inside the wells, thus preserving the intraretinal signal processing in prosthetic vision. Comparable glial response to that with flat implants suggests that migration and separation of the retinal cells by the walls does not cause additional stress. Furthermore, retinal migration into the honeycombs does not negatively affect its electrical excitability, while grating acuity matches the pixel pitch down to 40 µm and reaches the 27 µm limit of natural resolution in rats with 20 µm pixels. These findings pave the way for 3-D subretinal prostheses with pixel sizes of cellular dimensions.

Transcatheter or Surgical Aortic Valve Replacement in Patients With Severe Aortic Stenosis and Small Aortic Annulus: A Randomized Clinical Trial.

BACKGROUND: The optimal treatment in patients with severe aortic stenosis and small aortic annulus (SAA) remains to be determined. This study aimed to compare the hemodynamic and clinical outcomes between transcatheter aortic valve replacement (TAVR) and surgical aortic valve replacement (SAVR) in patients with a SAA. METHODS: This prospective multicenter international randomized trial was performed in 15 university hospitals. Participants were 151 patients with severe aortic stenosis and SAA (mean diameter <23 mm) randomized (1:1) to TAVR (n=77) versus SAVR (n=74). The primary outcome was impaired valve hemodynamics (ie, severe prosthesis patient mismatch or moderate-severe aortic regurgitation) at 60 days as evaluated by Doppler echocardiography and analyzed in a central echocardiography core laboratory. Clinical events were secondary outcomes. RESULTS: The mean age of the participants was 75.5±5.1 years, with 140 (93%) women, a median Society of Thoracic Surgeons predicted risk of mortality of 2.50% (interquartile range, 1.67%-3.28%), and a median annulus diameter of 21.1 mm (interquartile range, 20.4-22.0 mm). There were no differences between groups in the rate of severe prosthesis patient mismatch (TAVR, 4 [5.6%]; SAVR, 7 [10.3%]; P=0.30) and moderate-severe aortic regurgitation (none in both groups). No differences were found between groups in mortality rate (TAVR, 1 [1.3%]; SAVR, 1 [1.4%]; P=1.00) and stroke (TAVR, 0; SAVR, 2 [2.7%]; P=0.24) at 30 days. After a median follow-up of 2 (interquartile range, 1-4) years, there were no differences between groups in mortality rate (TAVR, 7 [9.1%]; SAVR, 6 [8.1%]; P=0.89), stroke (TAVR, 3 [3.9%]; SAVR, 3 [4.1%]; P=0.95), and cardiac hospitalization (TAVR, 15 [19.5%]; SAVR, 15 [20.3%]; P=0.80). CONCLUSIONS: In patients with severe aortic stenosis and SAA (women in the majority), there was no evidence of superiority of contemporary TAVR versus SAVR in valve hemodynamic results. After a median follow-up of 2 years, there were no differences in clinical outcomes between groups. These findings suggest that the 2 therapies represent a valid alternative for treating patients with severe aortic stenosis and SAA, and treatment selection should likely be individualized according to baseline characteristics, additional anatomical risk factors, and patient preference. However, the results of this study should be interpreted with caution because of the limited sample size leading to an underpowered study, and need to be confirmed in future larger studies. REGISTRATION: URL: https://www.clinicaltrials.gov; Unique identifier: NCT03383445.

The Tricuspid Valve: A Review of Pathology, Imaging, and Current Treatment Options: A Scientific Statement From the American Heart Association.

Tricuspid valve disease is an often underrecognized clinical problem that is associated with significant morbidity and mortality. Unfortunately, patients will often present late in their disease course with severe right-sided heart failure, pulmonary hypertension, and life-limiting symptoms that have few durable treatment options. Traditionally, the only treatment for tricuspid valve disease has been medical therapy or surgery; however, there have been increasing interest and success with the use of transcatheter tricuspid valve therapies over the past several years to treat patients with previously limited therapeutic options. The tricuspid valve is complex anatomically, lying adjacent to important anatomic structures such as the right coronary artery and the atrioventricular node, and is the passageway for permanent pacemaker leads into the right ventricle. In addition, the mechanism of tricuspid pathology varies widely between patients, which can be due to primary, secondary, or a combination of causes, meaning that it is not possible for 1 type of device to be suitable for treatment of all cases of tricuspid valve disease. To best visualize the pathology, several modalities of advanced cardiac imaging are often required, including transthoracic echocardiography, transesophageal echocardiography, cardiac computed tomography, and cardiac magnetic resonance imaging, to best visualize the pathology. This detailed imaging provides important information for choosing the ideal transcatheter treatment options for patients with tricuspid valve disease, taking into account the need for the lifetime management of the patient. This review highlights the important background, anatomic considerations, therapeutic options, and future directions with regard to treatment of tricuspid valve disease.

Integrating Upper-Limb Prostheses with the Human Body: Technology Advances, Readiness, and Roles in Human-Prosthesis Interaction.

Significant advances in bionic prosthetics have occurred in the past two decades. The field's rapid expansion has yielded many exciting technologies that can enhance the physical, functional, and cognitive integration of a prosthetic limb with a human. We review advances in the engineering of prosthetic devices and their interfaces with the human nervous system, as well as various surgical techniques for altering human neuromusculoskeletal systems for seamless human-prosthesis integration. We discuss significant advancements in research and clinical translation, focusing on upper limbprosthetics since they heavily rely on user intent for daily operation, although many discussed technologies have been extended to lower limb prostheses as well. In addition, our review emphasizes the roles of advanced prosthetics technologies in complex interactions with humans and the technology readiness levels (TRLs) of individual research advances. Finally, we discuss current gaps and controversies in the field and point out future research directions, guided by TRLs.

Hemodynamics and Wall Mechanics of Vascular Graft Failure.

Blood vessels are subjected to complex biomechanical loads, primarily from pressure-driven blood flow. Abnormal loading associated with vascular grafts, arising from altered hemodynamics or wall mechanics, can cause acute and progressive vascular failure and end-organ dysfunction. Perturbations to mechanobiological stimuli experienced by vascular cells contribute to remodeling of the vascular wall via activation of mechanosensitive signaling pathways and subsequent changes in gene expression and associated turnover of cells and extracellular matrix. In this review, we outline experimental and computational tools used to quantify metrics of biomechanical loading in vascular grafts and highlight those that show potential in predicting graft failure for diverse disease contexts. We include metrics derived from both fluid and solid mechanics that drive feedback loops between mechanobiological processes and changes in the biomechanical state that govern the natural history of vascular grafts. As illustrative examples, we consider application-specific coronary artery bypass grafts, peripheral vascular grafts, and tissue-engineered vascular grafts for congenital heart surgery as each of these involves unique circulatory environments, loading magnitudes, and graft materials.

High-Fidelity Reproduction of Visual Signals by Electrical Stimulation in the Central Primate Retina.

Electrical stimulation of retinal ganglion cells (RGCs) with electronic implants provides rudimentary artificial vision to people blinded by retinal degeneration. However, current devices stimulate indiscriminately and therefore cannot reproduce the intricate neural code of the retina. Recent work has demonstrated more precise activation of RGCs using focal electrical stimulation with multielectrode arrays in the peripheral macaque retina, but it is unclear how effective this can be in the central retina, which is required for high-resolution vision. This work probes the neural code and effectiveness of focal epiretinal stimulation in the central macaque retina, using large-scale electrical recording and stimulation ex vivo The functional organization, light response properties, and electrical properties of the major RGC types in the central retina were mostly similar to the peripheral retina, with some notable differences in density, kinetics, linearity, spiking statistics, and correlations. The major RGC types could be distinguished by their intrinsic electrical properties. Electrical stimulation targeting parasol cells revealed similar activation thresholds and reduced axon bundle activation in the central retina, but lower stimulation selectivity. Quantitative evaluation of the potential for image reconstruction from electrically evoked parasol cell signals revealed higher overall expected image quality in the central retina. An exploration of inadvertent midget cell activation suggested that it could contribute high spatial frequency noise to the visual signal carried by parasol cells. These results support the possibility of reproducing high-acuity visual signals in the central retina with an epiretinal implant.SIGNIFICANCE STATEMENT Artificial restoration of vision with retinal implants is a major treatment for blindness. However, present-day implants do not provide high-resolution visual perception, in part because they do not reproduce the natural neural code of the retina. Here, we demonstrate the level of visual signal reproduction that is possible with a future implant by examining how accurately responses to electrical stimulation of parasol retinal ganglion cells can convey visual signals. Although the precision of electrical stimulation in the central retina was diminished relative to the peripheral retina, the quality of expected visual signal reconstruction in parasol cells was greater. These findings suggest that visual signals could be restored with high fidelity in the central retina using a future retinal implant.

Cutibacterium acnes biofilm formation is influenced by bone microenvironment, implant surfaces and bacterial internalization.

BACKGROUND: The bacterial persistence, responsible for therapeutic failures, can arise from the biofilm formation, which possesses a high tolerance to antibiotics. This threat often occurs when a bone and joint infection is diagnosed after a prosthesis implantation. Understanding the biofilm mechanism is pivotal to enhance prosthesis joint infection (PJI) treatment and prevention. However, little is known on the characteristics of Cutibacterium acnes biofilm formation, whereas this species is frequently involved in prosthesis infections. METHODS: In this study, we compared the biofilm formation of C. acnes PJI-related strains and non-PJI-related strains on plastic support and textured titanium alloy by (i) counting adherent and viable bacteria, (ii) confocal scanning electronic microscopy observations after biofilm matrix labeling and (iii) RT-qPCR experiments. RESULTS: We highlighted material- and strain-dependent modifications of C. acnes biofilm. Non-PJI-related strains formed aggregates on both types of support but with different matrix compositions. While the proportion of polysaccharides signal was higher on plastic, the proportions of polysaccharides and proteins signals were more similar on titanium. The changes in biofilm composition for PJI-related strains was less noticeable. For all tested strains, biofilm formation-related genes were more expressed in biofilm formed on plastic that one formed on titanium. Moreover, the impact of C. acnes internalization in osteoblasts prior to biofilm development was also investigated. After internalization, one of the non-PJI-related strains biofilm characteristics were affected: (i) a lower quantity of adhered bacteria (80.3-fold decrease), (ii) an increase of polysaccharides signal in biofilm and (iii) an activation of biofilm gene expressions on textured titanium disk. CONCLUSION: Taken together, these results evidenced the versatility of C. acnes biofilm, depending on the support used, the bone environment and the strain.

Outcomes of tricuspid valve prostheses after heart transplantation: a systematic review.

Tricuspid regurgitation (TR) is the most common valvular pathology after heart transplantation (HTx) and endomyocardial biopsy (EMB) remains responsible for the majority of cases due to the high probability of structural valve damage. The aim of the present review was to describe the results of surgical management of severe tricuspid regurgitation through tricuspid valve replacement (TVR) after a previous HTx. A systematic review was conducted by searching Pubmed, ScienceDirect, SciELO, DOAJ, and Cochrane databases until June 2023 for publications reporting patients undergoing TVR surgery after a previous HTx. If no right heart valve surgery was undertaken, or a heterotopic heart transplant was performed, or if the concomitant procedure was performed during the transplant itself, the paper was excluded. Twenty articles met our inclusion criteria out of 1532 potentially eligible studies, with a total of 300 patients. Mean age was 55.1 ± 9.6 years, and 85.1% were male. The mean number of EMB per patient was 31.1 ± 5.5 with a mean time between HTx and TVR of 7.64 ± 3.31 years. Bioprostheses were used in 83.3% of cases and 75.0% of patients with a bioprosthesis were reported as alive at last follow-up. Tricuspid valve repair is a valuable option, but these patients will be susceptible to recurrent TR after EMB. TVR with a bioprosthesis may provide the optimal solution for this subset of patients, as EMB is not feasible with a mechanical valve.

Outcomes of lower extremity arterial bypass using the Human Acellular Vessel in patients with chronic limb-threatening ischemia.

OBJECTIVE: Patients with chronic limb-threatening ischemia (CLTI) and no great saphenous vein to use as a conduit for arterial bypass have a high risk for amputation despite advances in medical and endovascular therapies. This report presents findings from a U.S. Food and Drug Administration (FDA) supported study of the Human Acellular Vessel (HAV) (Humacyte Inc.) used as a conduit for arterial bypass in patients with CLTI and inadequate or absent autologous conduit. METHODS: The HAV is a 6-mm, 40-cm vessel created from human vascular smooth muscle cells seeded onto a polyglycolic acid scaffold pulsed in a bioreactor for 8 weeks as cells proliferate and the scaffold dissolves. The resultant vessel is decellularized, creating a nonimmunogenic conduit composed of collagen, elastin, and extracellular matrix. The FDA issued an Investigational New Drug for an intermediate-sized, single-center study of the HAV under the agency's Expanded Access Program in patients with advanced CLTI and inadequate or absent autologous conduit. Technical results and clinical outcomes were analyzed and reported. RESULTS: Between March 2021 and July 2023, 29 patients (20 males; mean age, 71 ± 11 years) underwent limb salvage operation using the HAV as a bypass conduit. Most patients had advanced CLTI (Rutherford class 5/6 in 72%; wound, ischemia, and foot infection stage 3/4 in 83%), and 97% had previously failed revascularization(s) of the extremity. Two HAVs were sewn together to attain the needed bypass length in 24 patients (83%). Bypasses were to tibial arteries in 23 patients (79%) and to the popliteal artery in 6 (21%). Technical success was 100%, and the 30-day mortality rate was 7% (2 patients). With 100% follow-up (median, 9.3 months), the limb salvage rate was 86% (25/29 patients). There were 16 reinterventions to restore secondary patency, of which 15 (94%) were successful. Primary and secondary patency of the HAV at 9 months were 59% and 71%, respectively. CONCLUSIONS: The HAV has demonstrated short- to intermediate-term safety and efficacy as an arterial bypass conduit in a complex cohort of patients with limb-threatening ischemia and no autologous options. This experience using the FDA's Expanded Access Program provides real-world data to inform regulatory deliberations and future trials of the HAV, including the study of the vessel as a first-line bypass conduit in less severe cases of chronic limb ischemia.

Impact of commissural alignment on the hemodynamic performance of supra-annular self-expandable transcatheter aortic valves.

BACKGROUND: Hemodynamic impact of commissural alignment (CA) with self-expandable transcatheter aortic valves (TAVR) has not been investigated yet. AIMS: To determine hemodynamic impact of CA with self-expandable TAVR. METHODS: Multicentric ambispective study comparing patients who underwent self-expandable TAVR in seven centers with the Evolut Pro/Pro+ (EP) (Medtronic) and Acurate neo2 (AN2) (Boston Scientific) with and without CA strategies. The degree of commissural misalignment (CMA) was assessed by computed tomography/angiography and 1-year transvalvular gradients/regurgitation evaluated by echocardiography. A matched comparison according to annular dimensions/eccentricity, prosthesis size/type, and baseline left ventricular function and gradients was performed. RESULTS: A total of 557 patients, mean age 80.7 ± 6.6 years, 61.4% men, and STS score of 4.3 ± 3.1% were analyzed. A CA technique was attempted in 215 patients (38.6%), including 113 patients with AN2 and 102 patients with EP. None/mild CMA was found in 158 (73.5% vs. 43.6% if no CA attempted, p < 0.001) with no differences between devices (AN2:75.2%; EP:71.6%, p = 0.545). Patients with moderate/severe CMA had a greater aortic peak gradient (22.3 ± 8.7 vs. 19.7 ± 8.5, p = 0.001), significantly greater progression of both peak (p = 0.002) and mean gradients (p = 0.001) after matching, and higher rate of central aortic regurgitation (1.2% vs. 0.4%, p = 0.005) at 1-year, but not a greater proportion of patients with mean gradient ≥ 10 mmHg. CONCLUSIONS: The use of CA strategies significantly reduced the rate of CMA for the self-expandable TAVR devices ACN2 and EP which was associated to lower transvalvular gradients and intra-prosthetic regurgitation progression at 1-year although no criteria of structural deterioration were met at this follow up. CLINICALTRIALS: org: NCT05097183.

Routine postdilation after 23 mm Sapien 3 Ultra implantation in the aortic position.

BACKGROUND: Residual transprosthetic gradient (TG) after transcatheter aortic valve replacement (TAVR) with balloon-expandable valves (BEV) may be due to suboptimal valve expansion. AIMS: To compare hemodynamics after TAVR with small BEV according to postdilation strategy. METHODS: This observational, retrospective cohort study included 184 consecutive patients from a single center treated with 23 mm Sapien 3 Ultra (Edwards Lifesciences) BEV implantation in the aortic position and enrolled between January 2020 and April 2023. Patients treated with routine postdilation (RP, n = 73) were compared to patients treated according to local standard practice (SP, n = 111). Primary endpoint was 30-day mean TG. Secondary endpoints were incidence of 30-day prosthesis-patient mismatch (PPM), technical success and device success. RESULTS: Thirty-day mean TG was lower in RP versus SP (12.3 ± 4.6 mmHg vs. 14.1 ± 5.7 mmHg, p = 0.031), and incidence of PPM was less common with RP versus SP (47.3% vs. 71.0%, p = 0.006). Technical success (98.6% vs. 99.1%, p = 0.637) and device success (93.1% vs. 90.1%, p = 0.330) did not differ between groups. Differences in 30-day mean TG were driven by patients at normal flow (12.1 ± 4.0 mmHg vs. 15.0 ± 5.5 mmHg, p = 0.014), while no differences were evident among patients at low flow (12.5 ± 5.5 mmHg vs. 11.7 ± 5.5 mmHg, p = 0.644). RP decreased height and increased width of BEV, and a linear regression established that final BEV width could predict 30-day mean TG (r = -0.6654, p < 0.0001). CONCLUSIONS: RP after TAVR with small BEV was associated with more favorable forward-flow hemodynamics than SP.

Commissural alignment and the ACURATE neo2 transcatheter aortic valve: Impact on valve performance.

BACKGROUND: Transcatheter aortic valve replacement (TAVR) is increasingly being used to treat severe aortic stenosis in younger patients. Accordingly, lifetime management regarding future reintervention and coronary access is a concern. AIMS: To assess the impact of commissural alignment on ACURATE neo2 transcatheter aortic valve (TAV) performance. METHODS: COMALIGN-neo2 was an observational, retrospective study enrolling consecutive TAVR patients treated with the ACURATE neo2 (October 2021 to October 2022). The degree of commissural (mis)-alignment (CMA) with the native aortic valve commissures was determined and transvalvular gradient, effective orifice area, patient-prosthesis mismatch (PPM), and aortic regurgitation (AR) were assessed. RESULTS: Among 825 patients, the mean age was 80.7 years and 42% were female. Commissural alignment was achieved in 60% of cases; mild (26%), moderate (9%), and severe misalignment (5%) were found less often. Severe PPM occurred more frequently in patients with severe CMA (14.7%) compared to aligned valves (p = 0.034). By multivariate analysis, severe CMA (odds ratio [OR]: 3.12, 95% confidence interval [CI] [1.09-8.90]; p = 0.033) and lack of postdilatation (OR: 3.85, [1.33-11.1]; p = 0.012) were associated with severe PPM. Higher rates of ≥mild AR (51.4%) were found in TAVs implanted with severe CMA compared to aligned (34.3%), mildly (38.1%) or moderately (36.0%) misaligned TAVs (p = 0.030). Multivariate analysis identified severe CMA (OR: 2.05, [1.05-4.02]; p = 0.037) to be an independent predictor of ≥mild AR. CONCLUSIONS: COMALIGN-neo2 is the largest study to date assessing the impact of commissural alignment on acute TAV performance. Severe CMA with the ACURATE neo2 platform was associated with worse valve hemodynamics and increased risk for mild AR.

Patient-specific computer simulation of transcatheter aortic valve replacement in patients with previous mechanical mitral prosthesis: A case series.

Transcatheter aortic valve replacement performed in patients with previously implanted mechanical mitral prosthesis represents a high risk procedure with several potential complications. We report a systematic use of a prediction model based on artificial intelligence to plan the interventional strategy in this challenging scenario.

Combined transcatheter aortic valve and tricuspid valve-in-valve implantation in a patient with a mitral mechanical prosthesis.

Despite progressively uncommon in Western countries, rheumatic heart disease still portrays a significant global burden. In elderly or high-surgical risk patients, plurivalvular disease may require a complex percutaneous approach. Transcatheter aortic valve implantation (TAVI) in patients with previous monoleaflet mitral prosthesis is challenging due to interference between the aortic valve and the rigid mitral mechanical prosthesis "ring." Prior cases report the use of CoreValve or Edwards Sapien aortic valves in patients with adequate mitro-aortic distance. Performing a second major procedure, such as tricuspid valve-in-valve (TVIV), sequentially during a single percutaneous intervention, increases treatment complexity. An 83-year-old woman with rheumatic heart disease, with previous implantation of a Bjork-Shiley monoleaflet mitral prosthesis, and Carpentier-Edwards 29 tricuspid bioprosthesis presented with decompensated heart failure due to severe aortic stenosis and tricuspid bioprosthesis stenosis. After HeartTeam discussion, the patient was deemed as inoperable due to a prohibitive surgical risk. As an alternative, a TAVI (Navitor FlexNav) and a transcatheter TVIV replacement (Edwards Sapiens 3 Ultra) were discussed and proposed, with both techniques being performed sequentially in a single procedure. TAVI in a patient with a previous monoleaflet mitral mechanical prosthesis and TVIV may be a feasible approach in inoperable patients with plurivalvular disease.

Outcomes related to penile prosthesis reservoir removal: a 7-year multi-institutional experience.

BACKGROUND: The 3-piece inflatable penile prosthesis (IPP) is the most widely used device for erectile dysfunction refractory to medications, containing a reservoir inserted into the retropubic space (RPS) or an alternative/ectopic space (AES). Indications for removal of the reservoir include malfunction, malposition, or infection. In revision cases without infection, reservoir removal is sometimes optional. AIM: We reviewed outcomes and complications related to reservoir removal from a large multi-institutional series. METHODS: We retrospectively reviewed databases at 6 institutions over 7 years. Patients with artificial urethral sphincter, urethral sling, or mini-jupette were excluded. OUTCOMES: Outcomes and complications related to IPP reservoir removal were analyzed. Data were collected, but only reservoir-related complications at surgery were included. Data were compared between the RPS and AES cohorts to evaluate differences with a χ2 test, with significance at P < .05. RESULTS: Of 215 cases, there were 172 RPS and 43 AES reservoirs. The mean patient age was 65.3 years. An overall 131 procedures were due to malfunction and 49 to malposition of an IPP component; 35 were secondary to infection. Among those retained (n = 44), reasons included reuse, avoiding surrounding structure damage, and difficult dissection. Among those removed (n = 171), 15 required a counterincision. To determine the statistical difference between those removed from the RPS and an AES, the χ2 test result was P = .00059, indicating a significant difference in the need for a counterincision between the groups. Complications included bladder perforation (n = 1) in the RPS group and an avulsion of the epigastric vessels requiring abdominal exploration (n = 1) in the AES group. To determine the statistical difference between RPS and AES complications, the χ2 test result was P = .365, indicating no significant difference between the groups. STRENGTHS AND LIMITATIONS: Strengths include being a multi-institutional study with high-volume skilled implanters. Limitations include being a retrospective review, with implanters exclusively performing penoscrotal incisions and not utilizing an infrapubic approach. Last, there was a lack of long-term follow-up with these patients. CONCLUSIONS: Removal of an IPP reservoir remains safe, with few intraoperative complications. Surgeons should be aware of the inferior epigastric vessels during removal in an AES or be willing to perform a counterincision to avoid injury to surrounding structures. Surgeons should also obtain preoperative imaging to identify the specific location of the reservoir and adjacent anatomy. This is the first multi-institutional study reviewing outcomes related to reservoir removal during IPP revision or removal surgery.

Minocycline-rifampin-impregnated penile prosthesis surfaces retain antimicrobial activity following irrigation with 0.05% chlorhexidine gluconate and antibiotic solutions.

BACKGROUND: 0.05% Chlorhexidine gluconate (CHG; Irrisept [IrriMax]) is a commercial wound irrigation solution approved by the Food and Drug Administration that has seen recent adoption in the field of prosthetic urology; however, no study has evaluated whether 0.05% CHG is compatible with the minocycline-rifampin-impregnated surface (InhibiZone) of the AMS 700 penile prosthesis (Boston Scientific). AIM: To evaluate whether 0.05% CHG alters the antibiotic efficacy of the minocycline-rifampin-impregnated penile prosthesis surface. METHODS: Discs (8 mm) were taken by a punch biopsy (Sklar) from sterile penile prosthesis reservoirs whose surfaces had been impregnated with rifampin and minocycline. Discs (n = 10) were suspended in 0.05% CHG, vancomycin and gentamicin, or normal saline for 2 minutes to simulate intraoperative irrigation. Discs were then rinsed in normal saline to remove any unbound solution and incubated with methicillin-sensitive Staphylococcus aureus for 48 hours. Adherent surface bacteria were suspended by shaking in a 0.3% Tween 20 solution, serially diluted, plated onto 3M PetriFilms, and counted. Kirby-Bauer disc diffusion assays were conducted to generalize findings across various organisms. OUTCOMES: Outcomes included (1) bacterial adherence to the implant surface measured as bacterial counts (in colony-forming units per milliliter) and (2) bacterial growth reduction measured as zones of inhibitions (in millimeters). RESULTS: Incubation of implant surfaces in 0.05% CHG did not alter recovered bacterial counts as compared with normal saline and vancomycin/gentamycin. Similarly, within a single bacterial species, 0.05% CHG and vancomycin/gentamycin did not alter zone-of-inhibition measurements in Kirby-Bauer disc diffusion studies. CLINICAL TRANSLATION: This study demonstrates in vitro that 0.05% CHG may be used directly on the minocycline-rifampin-impregnated surface without altering the antibiotic efficacy of the coating. STRENGTHS AND LIMITATIONS: Strengths include that this is the first study to evaluate if 0.05% CHG affected the minocycline-rifampin-impregnated surface. Limitations include the use of in vitro studies, which serve as a proxy for in vivo practices and may not be entirely accurate or translatable in a clinical setting. CONCLUSION: 0.05% CHG does not alter the antimicrobial activity of the minocycline-rifampin-impregnated surface as compared with vancomycin/gentamycin and normal saline in vitro; however, its efficacy in clinical practice remains to be evaluated.

Development and validation of 3-dimensional simulators for penile prosthesis surgery.

BACKGROUND: The acquisition of skills in penile prosthesis surgery has many limitations mainly due to the absence of simulators and models for training. Three-dimensional (3D) printed models can be utilized for surgical simulations, as they provide an opportunity to practice before entering the operating room and provide better understanding of the surgical approach. AIM: This study aimed to evaluate and validate a 3D model of human male genitalia for penile prosthesis surgery. METHODS: This study included 3 evaluation and validation stages. The first stage involved verification of the 3D prototype model for anatomic landmarks compared with a cadaveric pelvis. The second stage involved validation of the improved model for anatomic accuracy and teaching purposes with the Rochester evaluation score. The third stage comprised validation of the suitability of the 3D prototype model as a surgical simulator and for skill acquisition. The third stage was performed at 3 centers using a modified version of a pre-existing, validated questionnaire and correlated with the Rochester evaluation score. OUTCOME: We sought to determine the suitability of 3D model for training in penile prosthesis surgery in comparison with the available cadaveric model. RESULTS: The evaluation revealed a high Pearson correlation coefficient (0.86) between questions of the Rochester evaluation score and modified validated questionnaire. The 3D model scored 4.33 ± 0.57 (on a Likert scale from 1 to 5) regarding replication of the relevant human anatomy for the penile prosthesis surgery procedure. The 3D model scored 4.33 ± 0.57 (on a Likert scale from 1 to 5) regarding its ability to improve technical skills, teach and practice the procedure, and assess a surgeon's ability. Furthermore, the experts stated that compared with the cadaver, the 3D model presented greater ethical suitability, reduced costs, and easier accessibility. CLINICAL IMPLICATIONS: A validated 3D model is a suitable alternative for penile prosthesis surgery training. STRENGTHS AND LIMITATIONS: This is the first validated 3D hydrogel model for penile prosthesis surgery teaching and training that experts consider suitable for skill acquisition. Because specific validated guidelines and questionnaires for the validation and verifications of 3D simulators for penile surgery are not available, a modified questionnaire was used. CONCLUSION: The current 3D model for penile prosthesis surgery shows promising results regarding anatomic properties and suitability to train surgeons to perform penile implant surgery. The possibility of having an ethical, easy-to-use model with lower costs and limited consequences for the environment is encouraging for further development of the models.

Does climate impact inflatable penile prosthesis infection (IPP) risk? Assessment of temperature and dew point on IPP infections.

BACKGROUND: Variations in climate have been associated with a greater risk of surgical site infections, urinary tract infections, and changes in the skin microbiome; however, limited data exist on the impact of climate on inflatable penile prosthesis (IPP) infections. AIM: We sought to evaluate the impact of climate on the risk of IPP infections in a large international, multicenter cohort. METHODS: We performed a multi-institutional, retrospective study of patients undergoing IPP surgery. We then evaluated whether the month or season, during which surgery was performed, affected device infections. Implant infections were defined as infections requiring device explantation. A univariate logistic regression analysis was undertaken. OUTCOMES: Our primary outcome was implant infection. RESULTS: A total of 5289 patients with a mean age of 62.2 ± 10.8 years received IPP placement. There was a fairly even distribution of implants performed in each season. A total of 103 (1.9%) infections were recorded. There were 32 (31.1%) IPP infections in patients who underwent surgery in the summer, followed by 28 (27.2%) in the winter, 26 (25.2%) in the spring, and 17 (16.5%) in the fall. No statistically significant differences were recorded in terms of season (P = .19) and month (P = .29). The mean daily temperature (P = .43), dew point (P = .43), and humidity (P = .92) at the time of IPP placement was not associated with infection. CLINICAL IMPLICATIONS: These findings provide reassurance to prosthetic urologists that infection reduction strategies do not need to be tailored to local climate. STRENGTHS AND LIMITATIONS: Climate data were not directly recorded for each hospital, but rather based on the monthly averages in the city where the surgery was performed. CONCLUSION: The climate at time of IPP placement and time of year of surgery is not associated with IPP infection risk.

Long-term outcomes after plaque excision grafting for Peyronie's disease and subanalysis of patients who undergo the procedure despite preoperative counseling against it.

BACKGROUND: Plaque excision and grafting (PEG) has been recommended for patients with Peyronie's disease (PD) with >60° curvature and/or hinge effect and strong preoperative erections, while placement of an inflatable penile prosthesis (IPP) is recommended when rigidity is suboptimal. Nevertheless, many patients counseled to undergo an IPP decline and insist on proceeding with PEG due to personal preference or desire to avoid an implant. AIM: We aim to review long-term outcomes in patients who underwent PEG for PD at our institution and investigate whether there is any difference in long-term outcomes in patients who undergo PEG despite a recommendation to undergo IPP. METHODS: We conducted a retrospective chart review from 2007 to 2021 on PEG surgery performed at a single tertiary care institution in patients ≥18 years old who had >3 months of follow-up. OUTCOMES: Postoperative information was gathered from the electronic medical record, including postoperative erectile function, patient satisfaction, and the ability to engage in penetrative sexual intercourse. RESULTS: An overall 251 patients underwent PEG with a median follow-up of 12 months (IQR, 6-54). Among these, 54 (22%) were initially advised to undergo IPP but elected for PEG. Patients who underwent PEG despite counseling to undergo IPP reported lower postoperative ability to engage in intercourse (51% vs 76%). Seven (13%) patients initially advised to undergo IPP eventually received an IPP, relative to 7 (4%) initially advised to undergo PEG. CLINICAL IMPLICATIONS: Thorough preoperative assessment of erectile function and penile deformity can guide clinician counseling and manage patient expectations during decision making between PEG surgery and IPP implantation for PD. STRENGTHS AND LIMITATIONS: Limitations of this study include its retrospective nature, high attrition to follow-up, and risk of recall and selection bias. This is a large study with a median follow-up of 12 months, with a high-volume single surgeon who treats patients in a specialized population of complex cases. CONCLUSION: Patients who were initially counseled to undergo IPP due to suboptimal erectile rigidity but elected for PEG had worse postoperative ability to engage in penetrative intercourse, and a higher proportion of these patients eventually received an IPP.

Antibiotic dip and irrigation solutions confer increased antimicrobial efficacy of inflatable penile prosthesis hydrophilic surfaces compared with 0.05% chlorhexidine gluconate.

BACKGROUND: Chlorhexidine gluconate (CHG) (0.05%) has recently been suggested as both a dip for the hydrophilic surface and an irrigation solution in the setting of penile prosthesis (PP) surgery. AIM: The study sought to compare the antimicrobial efficacy of 0.05% CHG with vancomycin and gentamicin (VG) antibiotics as dip and/or irrigation solutions in the setting of a hydrophilic PP surface in vitro. METHODS: Sterile PPs with a hydrophilic coating were obtained. A series of experiments were performed to evaluate the efficacy of normal saline (NS), 0.05% CHG, or VG as dip and/or irrigation solutions to reduce methicillin-sensitive Staphylococcus aureus adhesion to PP surfaces. The 8-mm discs from PPs were incubated in 105 colony-forming units/mL of methicillin-sensitive S aureus for 48 hours, plated, and counted. Disc-diffusion tests were conducted by suspending 6-mm discs for 2 minutes in NS, 0.05% CHG, or VG, then placing them coated side down onto plates streaked with the following organisms: methicillin-sensitive S aureus, S epidermidis, Enterococcus, and Escherichia coli. After 24 hours of growth, zones of inhibition were measured. OUTCOMES: We found average bacterial counts (colony-forming units/mL) and zones of inhibition (mm) following a series of treatment protocols of PP discs. RESULTS: PP discs dipped in VG reduced bacterial adhesion to the implant surface >0.05% CHG (~5.5 log vs ~1.5 log; P < .01). Discs irrigated with either 0.05% CHG or NS removed all dip solution adsorbed to the hydrophilic surface, allowing bacterial growth. VG irrigation adsorbed to the hydrophilic surface even after 0.05% CHG or NS dips, reducing bacterial adherence (~3 log). Dipping and irrigating discs with VG was most effective in reducing adherent bacteria (~5.5 log) and was the only irrigation that showed antimicrobial activity. CLINICAL TRANSLATION: VG, when used both as a prophylactic dip and as an intraoperative irrigation solution for hydrophilic penile implant surfaces, has improved efficacy to 0.05% CHG and NS. STRENGTHS AND LIMITATIONS: This is the first study to compare the use of VG, 0.05% CHG, and NS as prophylactic dips and intraoperative irrigations for hydrophilic penile implant surfaces. Limitations include the use of in vitro studies, which serve as a proxy for in vivo practices and may not be entirely accurate nor translatable clinically. CONCLUSION: We demonstrated the superior efficacy of VG as a combined dip and irrigation solution for hydrophilic penile implant surfaces compared with 0.05% CHG.