Evaluation of average penis length and the thoughts of Turkish men and partners. Is surgery necessary?

The purpose of this study was to determine the average penis length and girth among the Turkish population, and to analyse the perspectives of couples. A total of 1703 males and 139 female partners participated in this study. All the participants completed a questionnaire and the flaccid and stretched penis length and girth were recorded. The results showed that the average flaccid penis length was 8.44 ± 2.28 cm and 12.27 ± 2.91 cm stretched, with girth of 8.23 ± 2.07 cm. Regarding the importance of penis size for a satisfying sexual experience, 18.5% of men thought penis length mattered, 9.9% considered thickness important, and 71.6% thought both were significant. A majority of participants, 67.8% of males and 76% of females, expressed that erect penis length was crucial for sexual pleasure. For a healthy sexual intercourse, 19.4% of the female partners emphasized the significance of penis length, 23.7% highlighted thickness, and 56.8% emphasized both factors for a fulfilling sexual relationship. A comparison between men's stretched penis length and the ideal length for partner satisfaction revealed no statistically significant difference (13 (4.8-21) cm vs. 12 (8-20) cm, p = 0.078). The average penis length and girth of Turkish males were found to be similar to the data in studies of this subject in literature. Both the males and their partners thought that erect penis length and girth were important for sexual intercourse. The males considering penis lengthening and thickening procedures should know whether or not their own penis is close to the average values, to avoid undergoing unnecessary surgeries.

[The role of seminal vesicles in male sexual function].

The seminal vesicle is an important accessory gland of the male reproductive system. In the past, some scholars focused more on its role in the fertilization process and neglected its relationship with male sexual function. Researches show that the seminal vesicle is involved in multiple processes such as sexual desire, penile erection, and ejaculation. Treatment of sexual dysfunction by medication targeting the seminal vesicle has achieved certain therapeutic effects. This article discusses the relationship between the seminal vesicle and sexual function in terms of physiopathology, clinical study and basic research, hoping to provide some new ideas on the clinical diagnosis and treatment of sexual dysfunction.

Efficient use of penile Doppler ultrasound for investigating men with erectile dysfunction.

BACKGROUND: Vasculogenic erectile dysfunction is the most common type of erectile dysfunction, and penile Doppler ultrasound (PDUS) is a useful tool to assess erectile hemodynamics in the clinician's effort to discuss prognosis and management strategies with the patient. AIM: We herein describe the PDUS protocol used at our center, including indications, technique, and data interpretation. METHODS: We describe our institutional experience with PDUS and discuss it in the context of a contemporary review of the literature for this investigation. OUTCOME: Our institutional PDUS protocol. RESULTS: To perform PDUS properly, adequate training, equipment, setting, technique, and interpretation are critical. The accuracy of PDUS is entirely predicated on achieving complete cavernosal smooth muscle relaxation. A redosing protocol optimizes the reliability and reproducibility of the hemodynamic data acquired during PDUS. A rigidity-based assessment is performed, and patients are scanned according to the erection rigidity achieved (full hardness) or by administration of maximum dose of the vasoactive agent. Peak systolic velocity is considered a measure of arterial inflow (normal, >30 cm/s), while end diastolic velocity evaluates the veno-occlusive mechanism (normal, <5 cm/s). After the procedure, the patient is evaluated to confirm detumescence. If the patient has a persistent penetration rigidity erection, intracavernosal phenylephrine is administered; however, if detumescence is not achieved with intracavernosal phenylephrine injections alone, corporal aspiration is potentially performed. CONCLUSION: PDUS is a valuable minimally invasive tool for erectile hemodynamics assessment and an accurate assessment of such, provided that complete cavernosal smooth muscle relaxation is achieved.

Argonaute 2 restored erectile function and corpus cavernosum mitochondrial function by reducing apoptosis in a mouse model of cavernous nerve injury.

PURPOSE: To determine whether the overexpression of the Argonaute RNA-induced silencing complex catalytic component 2 (Ago2) improves erectile function in mice after cavernous nerve injury (CNI). MATERIALS AND METHODS: Lentiviruses containing Ago2 open reading frame (ORF) mouse clone (Ago2 O/E) were used to overexpress Ago2, and lentiviruses ORF negative control particles (NC) were used as a negative control. Three days before preparing the CNI model, we injected lentiviruses into the penises of 8-week-old male C57BL/6 mice. Animals were then divided into four groups: the sham operation control group and the CNI+phosphate-buffered saline, CNI+NC, and CNI+Ago2 O/E groups. One week later, erectile function was assessed by electrically stimulating cavernous nerves bilaterally and obtaining intracavernous pressure parameters. Penile tissue was also collected for molecular mechanism studies. RESULTS: Ago2 overexpression improved erectile function in mice after CNI-induced erectile dysfunction (ED). Immunofluorescence staining and Western blot analysis showed that under Ago2 overexpressing conditions, the contents of endothelial cells, pericytes, and neuronal cells increased in the penile tissues of CNI mice, and this was attributed to reduced apoptosis and ROS production. In addition, we also found that Ago2 overexpression could restore penile mitochondrial function, thereby improving erectile function in CNI-induced ED mice. CONCLUSIONS: Our findings demonstrate that Ago2 overexpression can reduce penile cell apoptosis, restore penile mitochondrial function, and improve erectile function in CNI-induced ED mice.

Clinical outcomes of the Burnett "snake" maneuver shunt modification for ischemic priapism.

BACKGROUND: Major ischemic priapism (IP) is defined as a persistent penile erection for >4 hours. IP may cause serious complications, especially if prompt resolution is not achieved. Therefore, selecting the most effective and usable shunt technique is crucial in IP cases that are refractory to medical therapy. AIM: To compare the effectiveness and complication risks of distal corporoglanular shunt procedures with and without the Burnett "snake" maneuver. METHODS: We conducted a retrospective study of patients who presented with IP and underwent surgical treatment at our institution between 2005 and 2021. The patients were categorized into 2 groups: group 1 (n = 26) underwent distal shunt + Burnett snake maneuver, and group 2 (n = 56) underwent distal shunt-only. Clinical history, parameters of IP, details of medical and surgical treatments, and follow-up information were evaluated. OUTCOMES: Outcomes included differences in IP resolution and recurrence, functional erections, and complications between corporoglanular shunt procedures with and without the Burnett snake maneuver. RESULTS: In group 1, 24 of 26 patients (92.3%) experienced priapism resolution with a single surgical intervention, while this outcome was observed in 30 of 56 patients (53.6%) in group 2 (P < .001). Notably, priapism recurrence was significantly lower in group 1, occurring in 1 of 24 patients (4.2%), as opposed to 8 of 30 patients (26.6%) in group 2 (P < .001). Of the patients with documented sexual function status at follow-up, functional erections (capable of penetration with or without phosphodiesterase 5 inhibitors) were noted in 6 of 14 patients (42.8%) in group 1 and 13 of 26 patients (50%) in group 2 (P = .66). CLINICAL IMPLICATIONS: This study provides valuable insights regarding technical aspects of distal shunt procedures with and without the Burnett snake maneuver for treating major IP episodes. These results can help surgeons with clinical decision making for patients who present with IP. STRENGTH AND LIMITATIONS: Limitations include the single-site retrospective design with potential selection bias, inaccuracies in medical record data, challenges in controlling confounding variables, and the lack of validated questionnaire scores for erectile function evaluation. CONCLUSION: Our study demonstrates that modifying distal shunt procedures using the Burnett snake maneuver significantly improves priapism resolution and effectively prevents further priapism episodes without introducing additional complications or erectile function loss, thereby distinguishing it from distal shunt-only procedures.

A low testosterone level impairs erectile function by increasing endocan expression in rat penile corpus cavernosum.

BACKGROUND: The mechanism by which a state of low testosterone leads to erectile dysfunction (ED) has not been determined. Endocan is a novel marker of endothelial function. However, whether endocan is involved in the regulation of erectile function under low testosterone levels remains unclear. AIM: In this study we sought to determine whether a low-testosterone state inhibits erectile function by regulating endocan expression in the endothelial cells of the rat penile corpus cavernosum. METHODS: Thirty-six male Sprague-Dawley rats aged 8 weeks were randomly assigned to 6 groups (n = 6 per group) as follows: (1) control, (2) castration, (3) castration + testosterone treatment (treated with 3 mg/kg testosterone propionate per 2 days), (4) control + transfection (4 weeks after castration, injected with lentiviral vector (1 × 108 transduction units/mL, 10 µL), (5) castration + transfection, or (6) castration + empty transfection. One week after the injection, we measured the maximal intracavernous pressure/mean arterial pressure (ICPmax/MAP), serum testosterone and nitric oxide (NO) levels, and the expression of endocan, phospho-endothelial NO synthase (p-eNOS), eNOS, phospho-protein kinase B (p-AKT), and AKT in the rat penile corpus cavernosum. OUTCOMES: Under a low-androgen state, the expression of endocan in the rat penile corpus cavernosum was significantly increased, which inhibited the AKT/eNOS/NO signaling pathway and resulted in ED. RESULTS: In the castration group, the expression of endocan in the rat penile corpus cavernosum was significantly higher than that in the control group (P < .05). Additionally, the levels of p-AKT/AKT, p-eNOS/eNOS, and NO in the rat penile corpus cavernosum and ICPmax/MAP were significantly lower in the castration group than in the control group (P < .05). In the castration + transfection group compared with the castration group there was a significant decrease in the expression of endocan (P < .05) and an increase in the ratios of p-AKT/AKT, p-eNOS/eNOS, and ICPmax/MAP (P < .05) in the rat penile corpus cavernosum. CLINICAL IMPLICATIONS: Downregulating the expression of endocan in the penile corpus cavernosum may be a feasible approach for treating ED caused by hypoandrogenism. STRENGTHS AND LIMITATIONS: The results of this study indicte that endocan may affect NO levels and erectile function through multiple signaling pathways, but further experiments are needed to clarify the relationship between endocan and androgens. CONCLUSION: A low-testosterone state inhibits the AKT/eNOS/NO signaling pathway by increasing the expression of endocan in the rat penile corpus cavernosum and impairing erectile function in rats. Decreasing the expression of endocan in the penile corpus cavernosum can improve erectile function in rats with low testosterone levels.

Comparison of erectile and ejaculatory functional outcomes between unilateral and bilateral cavernosal rupture in penile fractures.

This study aimed to compare the erectile and ejaculatory functional outcomes of unilateral and bilateral ruptures of the corpus cavernosum in penile fractures. Sixty patients' data were analyzed retrospectively between June 2020 and January 2023. The patients were divided into two groups based on the affected corpus cavernosum (unilateral and bilateral). Preoperative and postoperative 3rd-, 6th-, and 12th-month self-estimated intravaginal-ejaculation-latency-time (IELT), and international index of erectile function-erectile function (IIEF-EF) scores as well as the presence of urethral injury were compared. Bilateral corpus cavernosum fractures were detected in 18.3% of the patients. The IIEF-EF scores of both groups at 3rd-, 6th-, and 12th-month were found to be significantly lower than the preoperative scores (unilateral group:24.1 ± 2.7 vs 23.2 ± 3.5 and 23.3 ± 3.4, respectively, p = 0.011 and 0.014, respectively; bilateral group: 24 ± 1.9 vs 23 ± 1.8 and 23.2 ± 1.5, respectively, p = 0.027 and 0.047, respectively). No significant difference was found between the preoperative and the postoperative 12th month IIEF-EF scores in either group (unilateral group: 24.1 ± 2.7 vs 23.4 ± 3.6, p = 0.207;bilateral group:24 ± 1.9 vs 23.2 ± 1.5, p = 0.057). The self-estimated IELTs of both groups at the postoperative 3rd, 6th, and 12th months demonstrated a significant increase from the preoperative values (unilateral group: 221.6 ± 81.8 vs 252 ± 94.6, 256.5 ± 97.6, and 250.5 ± 104.8, respectively, p < 0.001; bilateral group:241.8 ± 61.6 vs 278.1 ± 55.4, 281.8 ± 56.1, and 283.6 ± 54.2, respectively, p = 0.041, 0.030, and 0.047, respectively). The changes in self-estimated IELTs and IIEF-EF scores between the preoperative period and the postoperative 3rd, 6th, and 12th-months were compared, and no statistical difference was found between patients with unilateral and bilateral corpus cavernosum fractures (p > 0.05). In conclusion, no significant difference in erectile function was found in either group at the 12-month follow-up, and the self-estimated IELTs were found to be prolonged in both groups. Furthermore, no difference was noted between the groups at any follow-up. To explain the effects of unilateral and bilateral injuries on erectile and ejaculatory functions, further studies with a larger-number of patients are necessary.

Krause corpuscles are genital vibrotactile sensors for sexual behaviours.

Krause corpuscles, which were discovered in the 1850s, are specialized sensory structures found within the genitalia and other mucocutaneous tissues1-4. The physiological properties and functions of Krause corpuscles have remained unclear since their discovery. Here we report the anatomical and physiological properties of Krause corpuscles of the mouse clitoris and penis and their roles in sexual behaviour. We observed a high density of Krause corpuscles in the clitoris compared with the penis. Using mouse genetic tools, we identified two distinct somatosensory neuron subtypes that innervate Krause corpuscles of both the clitoris and penis and project to a unique sensory terminal region of the spinal cord. In vivo electrophysiology and calcium imaging experiments showed that both Krause corpuscle afferent types are A-fibre rapid-adapting low-threshold mechanoreceptors, optimally tuned to dynamic, light-touch and mechanical vibrations (40-80 Hz) applied to the clitoris or penis. Functionally, selective optogenetic activation of Krause corpuscle afferent terminals evoked penile erection in male mice and vaginal contraction in female mice, while genetic ablation of Krause corpuscles impaired intromission and ejaculation of males and reduced sexual receptivity of females. Thus, Krause corpuscles of the clitoris and penis are highly sensitive mechanical vibration detectors that mediate sexually dimorphic mating behaviours.

Preoperative high serum total testosterone levels predict preserved postoperative sexual function in patients after nerve-sparing robot-assisted radical prostatectomy.

OBJECTIVE: To assess the association among preoperative total testosterone levels, postoperative sexual function, and prognosis after robot-assisted radical prostatectomy. METHODS: Patients who underwent robot-assisted radical prostatectomy in our institution were included in the study. Based on preoperative total testosterone levels, they were divided into low (<3.0 ng/mL) and high (≥3.0 ng/mL) total testosterone groups. Sexual function was evaluated using the International Index of Erectile Function scores, Expanded Prostate Cancer Index Composite scores, and the potency rate from preoperatively to 12 months after surgery. Oncological outcomes were evaluated based on biochemical recurrence. RESULTS: Out of 233 patients included, no significant difference in sexual function was found between the high (n = 183) and the low (n = 50) total testosterone groups at any point before or after surgery. However, in nerve-sparing cases, preservation in postoperative sexual function was observed only in the high total testosterone group (International Index of Erectile Function scores and Expanded Prostate Cancer Index Composite sexual function scores, at any point after surgery, p < 0.05; potency rate, at 3, 6, and 12 months after surgery; p < 0.05). Additionally, the high total testosterone group showed better biochemical recurrence-free survival than the low total testosterone group (p = 0.008). CONCLUSIONS: In the high total testosterone group, preservation in sexual function was observed after the nerve-sparing procedure, while the biochemical recurrence rate was low. Therefore, patients with high levels of total testosterone may be advised to consider nerve-sparing interventions.

Targeting Adenosine A2b Receptor Promotes Penile Rehabilitation of Refractory Erectile Dysfunction.

The mechanisms of adenosine and specific adenosine receptor subtypes in promoting penile rehabilitation remain unclear. Single-cell RNA sequencing of human corpus cavernosum,  adenosine deaminase (ADA) and adenosine receptors knock-out mice (ADA-/-, A1-/-, A2a-/-, A2b-/-, and A3-/-), and primary corpus cavernosum smooth muscle cells are used to determine receptor subtypes responsible for adenosine-induced erection. Three rat models are established to characterize refractory erectile dysfunction (ED): age-related ED, bilateral cavernous nerve crush related ED (BCNC), and diabetes mellitus-induced ED. In single-cell RNA sequencing data, the corpus cavernosum of ED patients show a decrease in adenosine A1, A2a and A2b receptors. In vivo, A2b receptor knock-out abolishes adenosine-induced erection but not that of A1, A2a, or A3 receptor. Under hypoxic conditions in vitro, activating the A2b receptor increases HIF-1α and decreases PDE5 expression. In refractory ED models, activating the A2b receptor with Bay 60-6583 improves erectile function and down-regulates HIF-1α and TGF-ß. Administering Dipyridamole (40 mg Kg-1) to BCNC rats improve penile adenosine levels and erectile function. Our study reveals that the A2b receptor mediates adenosine-induced penile erection. Activating the A2b receptor promotes penile rehabilitation of refractory ED by alleviating hypoxia and fibrosis.

Trends, safety, and efficacy of wearable male sexual devices.

INTRODUCTION: The prevalence of male sexual dysfunction (MSD) increases with age, with >50% of men aged >40 years reporting erectile dysfunction (ED). In recent years, wearable male sex devices (WMSDs) have been increasingly utilized by patients and recommended by sexual medicine clinicians. OBJECTIVES: This study seeks to investigate the safety and efficacy of products currently marketed for the treatment of MSD. METHODS: Available products for WMSDs were reviewed by analyzing product websites, forums, advertisements, and clinical recommendations. Qualitative comparisons were based on patient reviews, cost, and specific features. Investigatory evidence and Food and Drug Administration status were also reviewed. Additionally, Google Trends was used to determine the popularity of devices over time. RESULTS: Eight WMSDs for the treatment of MSD and enhancement of sexual pleasure were reviewed. Constriction bands, such as the Maintain Ring Loop, Eddie by Giddy, and Xialla, have shown significant benefits in clinical trials and were the most popular devices among patients. Smart devices can provide real-time feedback on erectile quality and/or sexual performance. Similar to the RigiScan, the Adam sensor provides feedback on erectile quality while monitoring changes in penile tumescence during sleep with additional analysis available through a mobile application. Neuromodulation devices such as the Morari Patch and vPatch/in2 Patch use electrical stimulation to delay ejaculation and improve sexual function. The FirmTech Performance Ring uses sensors to track the vital signs of erectile fitness with clinical trials ongoing. CONCLUSIONS: Overall, this review describes the available investigatory evidence for a range of WMSDs and highlights the potential benefits and limitations of these devices in treating MSD and enhancing sexual pleasure. Further research is needed to evaluate the effectiveness of these devices and to determine which ones may be the most suitable for individual patients.

Penile erection and cardiovascular function: effects and pathophysiology.

Penile erection (PE) is a hemodynamic event that results from a neuroendocrine process, and it is influenced by the cardiovascular status of the patient. However, it may also modulate an individual's cardiovascular events. The present study provides the mechanisms involved in the association of PE and cardiovascular function. Erection upsurges the cardiac rate, blood pressure, and oxygen uptake. Sex-enhancing strategies, such as phosphodiesterase inhibitors, alprostadil, and testosterone also promote vasodilatation and cardiac performance, thus preventing myocardial infarction. More so, drugs that are used in the treatment of hypertensive heart diseases (such as angiotensin system inhibitors and ß-blockers) facilitate vasodilatation and PE. These associations have been linked with nitric oxide- and testosterone-dependent enhancing effects on the vascular endothelium. In addition, impaired cardiovascular function may negatively impact PE; therefore, impaired PE may be a pointer to cardiovascular pathology. Hence, evaluation of the cardiovascular status of an individual with erectile dysfunction (ED) is essential. Also, employing strategies that are used in maintaining optimal cardiac function may be useful in the management of ED.

A novel strategy to induce penile erection during penile doppler ultrasound: oral sildenafil administration plus alprostadil injection.

OBJECTIVES: To evaluate the efficacy of a novel approach to achieve the optimal penile erection during the penile doppler ultrasound (PDU) examination, which was oral sildenafil combined alprostadil injection. MATERIALS AND METHODS: A total of 60 ED patients were enrolled in our prospective study, and they were randomly assigned to two group with different PDU order. The approaches assisted the PDU included two models, mode A meaning injection of 15 µg alprostadil and model B meaning oral sildenafil 100 mg plus injection of 15 µg alprostadil. The PDU parameters were measured continuously before induced erection, and 5, 10, 15, 20, 25 min. RESULTS: Each group included 30 ED patients with similar clinical characteristics. After pooling the results together, the PSV, EDV, and RI were all improved significantly, when adding the oral sildenafil administration to assist PDU. Also, the clinical response of oral sildenafil administration plus alprostadil injection was better than that in alprostadil injection alone (p = 0.016). The arterial ED were decreased from 31.67% to 15.00% with the P value 0.031, and the mixed ED was also decreased statistically (23.33% vs 8.33%, p = 0.024). CONCLUSION: Oral sildenafil administration plus alprostadil injection could improve the diagnostic accuracy of PDU.

Ejaculatory and erectile function outcomes following holmium laser enucleation of the prostate.

PURPOSE: Holmium laser enucleation of the prostate (HoLEP) is a surgical treatment option for benign prostatic hyperplasia (BPH). Many men develop retrograde ejaculation postprocedure, but there is conflicting evidence regarding sexual function outcomes post-HoLEP. We sought to examine significant variations in patient-reported erectile and ejaculatory function within 12 months post-HoLEP. MATERIALS AND METHODS: We conducted a retrospective study for patients who underwent HoLEP between Nov 2018 and Feb 2022. Of the reviewed patients, 277 patients met inclusion criteria and completed pre and postoperative questionnaires, which included the Male Sexual Health Questionnaire- Ejaculatory Dysfunction (MSHQ-EJD) and the International Index of Erectile Function/Sexual Health Inventory for Men (IIEF-5/SHIM). Surveys were provided to patients up to 12 months postprocedure. Demographics and comorbidities associated with sexual dysfunction were collected. Responses to each question were analyzed to detect sub-categorical variations in sexual function as the secondary objective. Data was analyzed by using a linear mixed model. RESULTS: There was a significant decline in total scores for the MSHQ-EJD (8.70 pre-HoLEP vs. 6.58 post HoLEP, p ≤ 0.001) including a significant decline (p < 0.005) in questions 1-3 which assess ejaculatory ability, strength, and volume. There was not a significant decline in question 4 which assesses bother (2.552 pre-HoLEP vs. 3.119 post-HoLEP, p = 0.526). There was not a significant decline in the IIEF-5/SHIM postoperatively (11.51 pre-HoLEP vs. 13.327 post-HoLEP, p = 0.498). CONCLUSIONS: Patients undergoing HoLEP do not experience a decline in erectile function. Patients do experience a decline in ejaculatory function but did not find this bothersome.

Cldn4 overexpression promotes penile cavernous smooth muscle cell fibrotic response via the JNK signaling pathway.

BACKGROUND: Erectile dysfunction (ED), defined as the inability to achieve or maintain a penile erection sufficient to satisfy sexual behavior, is prevalent worldwide. AIM: Using previous research, bioinformatics, and experimental confirmation, we aimed to discover genes that contribute to ED through regulating hypoxia in corpus cavernosum smooth muscle cells (CCSMCs). METHODS: We used the Gene Expression Omnibus to acquire the sequencing data of the corpus cavernosum transcriptome for diabetic ED and nerve injury type ED rats. We intersected the common differentially expressed genes. Further verification was performed using single cell sequencing. Real-time quantitative polymerase chain reaction and immunofluorescence were used to investigate whether the differentially expressed genes are found in the corpus cavernosum. We used induced hypoxia to assess cell viability changes, and we developed a lentivirus overexpressing Cldn4 for in vitro and in vivo experiments to measure changes in JNK signaling, fibrosis, hypoxia, and erectile function. OUTCOMES: Our results indicate that targeting the JNK pathway and decreasing local hypoxia may be better options for therapeutic intervention to improve erectile function. RESULTS: We identified Cldn4 and found its expression increased in the corpora cavernosa of the 2 datasets. In addition, we found that hypoxia can increase the expression of Cldn4, activate the JNK signaling pathway, and exacerbate fibrosis in CCSMCs. Cldn4 overexpression in CCSMCs activated the JNK signaling pathway and increased fibrotic protein expression. Last, rat corpus cavernosum overexpressing Cldn4 activated the JNK signaling pathway, increased local fibrosis, and impaired erectile function. CLINICAL IMPLICATIONS: Through bioinformatics and in vitro and in vivo experiments, we found that Cldn4 has a negative effect on ED, and targeting Cldn4 may provide new ideas for ED treatment. STRENGTHS AND LIMITATIONS: Although we have identified Cldn4 as a potential target for ED treatment, we have only conducted preliminary validation on CCMSCs, and we still need to further validate in other cell lines. CONCLUSION: CCSMC hypoxia leads to increased Cldn4, in both nerve injury and diabetic ED rat models, and promotes fibrosis by activating the JNK signaling pathway.

The usefulness of shear wave elastography in evaluating erectile dysfunction severity before and after prostaglandin E1 test.

Prostaglandin E1 intracavernous injection test is an established method for diagnosing erectile dysfunction. However, the evaluation is non-objective and often influenced by the evaluator's subjectivity. Herein, we measured and objectively evaluated shear wave elastography results of the corpus cavernosum before and after injection in 16 patients who underwent prostaglandin E1 testing. The response score of prostaglandin E1 tests were "1" in 2 cases, "2" in 2 cases, and "3" in 12 cases. The average transmission velocity before the injection and at the time of maximum erection after the injection were 2.21 m/s and 1.57 m/s, respectively. Transmission velocity decreased during erection in 14 of 16 cases (87.5%). The overall rate of change in transmission velocity due to injection was -26.7% and was significantly different between the poor (responses 1 and 2: -16.1%) and good erection (response 3: -30.2%) groups. To the best of our knowledge, this is the first attempt to evaluate erectile phenomenon using percutaneous ultrasonic elastography in Japan. Rate of change in shear wave transmission velocity due to prostaglandin E1 injection in the corpus cavernosum penis was associated with the degree of erection. Therefore, the rate of change in shear wave transmission velocity in the corpus cavernosum penis could be used as an objective index of erectile phenomenon. Percutaneous ultrasonic elastography is a non-invasive and useful test method for diagnosing erectile dysfunction, determining the therapeutic effect, and predicting prognosis.

Corpora cavernosa fibroblasts mediate penile erection.

Penile erection is mediated by the corpora cavernosa, a trabecular-like vascular bed that enlarges upon vasodilation, but its regulation is not completely understood. Here, we show that perivascular fibroblasts in the corpora cavernosa support vasodilation by reducing norepinephrine availability. The effect on penile blood flow depends on the number of fibroblasts, which is regulated by erectile activity. Erection dynamically alters the positional arrangement of fibroblasts, temporarily down-regulating Notch signaling. Inhibition of Notch increases fibroblast numbers and consequently raises penile blood flow. Continuous Notch activation lowers fibroblast numbers and reduces penile blood perfusion. Recurrent erections stimulate fibroblast proliferation and limit vasoconstriction, whereas aging reduces the number of fibroblasts and lowers penile blood flow. Our findings reveal adaptive, erectile activity-dependent modulation of penile blood flow by fibroblasts.