Intracavernosal Injection for the Diagnosis, Evaluation, and Treatment of Erectile Dysfunction: A Review

Efficacy and safety of malleable penile prosthesis compared to inflatable penile prosthesis in erectile dysfunction patients

INTRODUCTION

Erectile dysfunction can cause self-withdrawal and decreased quality of life. Patients who do not respond to pharmacological therapy and other conservative treatments are urged to undergo penile prosthesis implantation. Malleable penile prosthesis was the first prosthesis developed, but then inflatable penile prosthesis was developed to give a more natural erection. There is no meta-analysis comparing inflatable and malleable penile prostheses in terms of safety and efficacy. This study is conducted to evaluate patient and partner satisfaction, ease of use, mechanical failure, and infection rate in patients who underwent penile prosthesis implantation.

METHOD

This meta-analysis followed Preferred Reporting Items for Systematic Review and Meta-analysis (PRISMA) protocols. Five eligible studies were included from Pubmed, Scopus, ScienceDirect, and SemanticScholar databases.

RESULT

In this study, patient and partner satisfaction are significantly better (OR 3.39, 95% CI 1.66-6.93, p = 0.0008) (OR 2.32, 95% CI 1.75-3.08, p < 0.00001). Mechanical failure is also significantly higher in inflatable penile prostheses (OR 5.60, 95% CI 2.02-15.53, p = 0.0009). There is no significant difference in terms of ease of use and infection rate in inflatable or malleable penile prostheses.

CONCLUSIONS

This study concluded that inflatable penile prosthesis is better in terms of patient and partner satisfaction, but mechanical failures occur more frequently in this type of prosthesis.

Low-intensity shockwave therapy improves baseline erectile function: a randomized sham-controlled crossover trial

Background

Low-intensity shockwave therapy for erectile dysfunction is emerging as a promising treatment option.

Aim

This randomized sham-controlled crossover trial assessed the efficacy of low-intensity shockwave therapy in the treatment of erectile dysfunction.

Methods

Thirty-three participants with organic erectile dysfunction were enrolled and randomized to shockwave therapy (n = 17) or sham (n = 16). The sham group was allowed to cross over to receive shockwave therapy after 1 month.

Outcomes

Primary outcomes were the changes in Sexual Health Inventory for Men (SHIM) score and Erection Hardness Score at 1 month following shockwave therapy vs sham, and secondary outcomes were erectile function measurements at 1, 3, and 6 months following shockwave therapy.

Results

At 1 month, mean SHIM scores were significantly increased in the shockwave therapy arm as compared with the sham arm (+3.0 vs -0.7, P = .024). Participants at 6 months posttreatment (n = 33) showed a mean increase of 5.5 points vs baseline (P < .001), with 20 (54.6%) having an increase ≥5. Of the 25 men with an initial Erection Hardness Score <3, 68% improved to a score ≥3 at 6 months. When compared with baseline, the entire cohort demonstrated significant increases in erectile function outcomes at 1, 3, and 6 months after treatment.

Clinical Implications

In this randomized sham-controlled crossover trial, we showed that 54.6% of participants with organic erectile dysfunction met the minimal clinically important difference in SHIM scores after treatment with low-intensity shockwave therapy.

Strengths and Limitations

Strengths of this study include a sham-controlled group that crossed over to treatment. Limitations include a modest sample size at a single institution.

Conclusions

Low-intensity shockwave therapy improves erectile function in men with erectile dysfunction as compared with sham treatment, which persists even 6 months after treatment.

Clinical Trial Registration

ClinicalTrials.gov NCT04434352.

Safety and Effectiveness of Repeated Botulinum Toxin A Intracavernosal Injections in Men with Erectile Dysfunction Unresponsive to Approved Pharmacological Treatments: Real-World Observational Data

Intracavernosal injections of botulinum toxin A (BTX/A ic) may be effective for difficult-to-treat erectile dysfunction (ED). This is a retrospective case series study of the effectiveness of repeated off-label BTX/A ic (onabotulinumtoxinA 100U, incobotulinumtoxinA 100U or abobotulinumtoxinA 500U) in men with ED and insufficient response to phosphodiesterase type 5 inhibitors (PDE5-Is) or prostaglandinE1 intracavernosal injections (PGE1 ICIs), defined as an International Index of Erectile Function-Erectile Function domain score (IIEF-EF) < 26 on treatment. Further injections were performed on patients' requests, and the files of men who underwent at least two injections were reviewed. The response to BTX/A ic was defined as the achievement of the minimally clinically important difference in IIEF-EF adjusted to the severity of ED on treatment at baseline. Out of 216 men treated with BTX/A ic and PDE5-Is or PGE1-ICIs, 92 (42.6%) requested at least a second injection. The median time since the preceding injection was 8.7 months. In total, 85, 44 and 23 men received, respectively, two, three and four BTX/A ic. The overall response rate was 77.5%: 85.7% in men with mild ED, 79% for moderate ED and 64.3% for severe ED on treatment. The response increased with repeated injections: 67.5%, 87.5% and 94.7%, respectively, after the second, third and fourth injections. Post-injection changes in IIEF-EF were similar across injections. The time from injection to request for a further injection varied little. Four men reported penile pain at the time of injection (1.5% of all injections), and one experienced a burn at the penile crus. Repeated BTX/A injections combined with PDE5-Is or PGE1-ICIs produced an effective and durable response, with acceptable safety.

A review on pharmacological options for the treatment of erectile dysfunction: state of the art and new strategies

INTRODUCTION

Erectile dysfunction (ED) affects between 12.9% and 28.1% of men worldwide, presenting a strong aged-correlated prevalence. Several pharmacological treatments are currently available for ED, which can be classified into oral, injection, and topical/intraurethral therapies.

AREAS COVERED

Extensive research on PubMed/MEDLINE until February 2023 was performed. For each of the aforementioned drug classes, available molecules, and formulations, their efficacy and most common adverse events as well as general guidelines on prescription were investigated and extensively described. A glimpse into future directions regarding ED pharmacotherapy is also present.

EXPERT OPINION

In recent years, there have been significant developments in pharmacological treatments for ED. It is essential for physicians to identify the best treatment option for patients based on their preferences and sexual habits. The treatment approach for ED has shifted from a sequential to a parallel paradigm, where all treatment options are available as first-line therapies. While there are promising regenerative therapies for ED, such as shockwaves and platelet-rich plasma injections, pharmacological treatment is still the most effective option for most patients.

Penile Rehabilitation after Prostate Cancer Treatment: Which Is the Right Program?

The management of sexual complications after treatment of localized prostate cancer, such as erectile dysfunction, changes in the length of the penis, pain during sexual intercourse, and lack of orgasm, is still an unsolved problem with an important impact on patients’ quality of life. In this review, we summarize the current scientific literature about the rehabilitation of erectile dysfunction after prostate cancer treatment. The therapy for penile rehabilitation includes different types of treatments: the combination of phosphodiesterase type 5 inhibitors (PDE5-I) and the vacuum erectile device (VED) are considered first-line treatment options. When therapy begins, the duration of treatment, the dosage and the drug used all play very important roles in the treatment outcome. Intracavernous injection (ICI) therapy represents the second-line option for patients ineligible for PDE5-I therapy. Technological development has led to the emergence of devices for the stimulation of the penis without the use of drugs, such as penile vibratory stimulation (PVS) for stimulation of ejaculation in spinal cord injury and low-intensity extracorporeal shockwave therapy (LIESWT). The rapid diffusion of the latter, thanks to its easy use, attains good results without side effects. The panorama of penile rehabilitation after PC treatments is vast and many studies are needed, especially on new technologies, to find the best therapeutic regimen possible, personalized to the patient’s characteristics and the type of treatment for PC.

The management of erectile dysfunction in men with diabetes mellitus unresponsive to phosphodiesterase type 5 inhibitors

INTRODUCTION

Erectile dysfunction is associated with diabetes mellitus with an estimated prevalence of 52.5% in the diabetic population. The first-line therapy for erectile dysfunction is phosphodiesterase type 5 inhibitors, but data suggest that diabetic men may be less responsive than non-diabetic men. Thus, other treatments, including intracavernosal injections, intraurethral prostaglandin, vacuum erection devices and penile prosthetic surgery, should be considered in management of diabetic men with erectile dysfunction refractory to phosphodiesterase type 5 inhibitors. Furthermore, combination therapy of phosphodiesterase type 5 inhibitors and other oral treatments such as arginine or l-carnitine may have synergistic effects resulting in better outcomes. In addition, there are novel therapies such as low-intensity shockwave therapy and stem-cell therapy, which may also be effective in targeted treatment modalities. Furthermore, studies suggest that erectile dysfunction can be improved by targeting concurrent comorbidities or metabolic diseases such as depression, hypertension, hypogonadism, and dyslipidaemia. We present an evidence-based narrative review focusing on the management of erectile dysfunction in diabetic men who have not responded to phosphodiesterase type 5 inhibitors.

CONCLUSIONS

Both clinicians and patients should be aware of the different management options in diabetic patients who have not responded to phosphodiesterase type 5 inhibitors.

Emerging structural and pathological analyses on the erectile organ, corpus cavernous containing sinusoids

Background

The corpus cavernosum (CC) containing sinusoids plays fundamental roles for erection. Analysis of pathological changes in the erectile system is studied by recent experimental systems. Various in vitro models utilizing genital mesenchymal-derived cells and explant culture systems are summarized.

Methods

3D reconstruction of section images of murine CC was created. Ectopic chondrogenesis in aged mouse CC was shown by a gene expression study revealing the prominent expression of Sox9. Various experimental strategies utilizing mesenchyme-derived primary cells and tissue explants are introduced.

Main Findings

Possible roles of Sox9 in chondrogenesis and its regulation by several signals are suggested. The unique character of genital mesenchyme is shown by various analyses of external genitalia (ExG) derived cells and explant cultures. Such strategies are also applied to the analysis of erectile contraction/relaxation responses to many signals and aging process.

Conclusion

Erectile dysfunction (ED) is one of the essential topics for the modern aged society. More comprehensive studies are necessary to reveal the nature of the erectile system by combining multiple cell culture strategies.

Management of male erectile dysfunction: From the past to the future

Erectile dysfunction is a common disease of the male reproductive system, which seriously affects the life quality of patients and their partners. At present, erectile dysfunction is considered as a social-psychological-physiological disease with complex etiology and various treatment methods. Oral PDE5I is the first-line treatment for erectile dysfunction with the advantages of high safety, good effect and non-invasiveness. But intracavernosal injection, hormonal replacement therapy, vacuum erection device, penile prosthesis implantation can also be alternative treatments for patients have organic erectile dysfunction or tolerance to PDE5I. With the rapid development of technologies, some new methods, such as low-intensity extracorporeal shock wave and stem cell injection therapy can even repair the organic damage of the corpora cavernosa. These are important directions for the treatment of male erectile dysfunction in the future. In this mini-review, we will introduce these therapies in detail.

Intra-cavernosal injection of botulinum toxin in the treatment of erectile dysfunction: a systematic review and meta-analysis

OBJECTIVE

To evaluate the role of botulinum toxin in treating erectile dysfunction as a novel treatment strategy avoiding morbid and irreversible surgeries.

METHODS

A systematic review of literature was conducted from January 1990 through July 31, 2021. Search engines used included PubMed, Embase and Medline databases, to identify studies investigating botulinum toxin in erectile dysfunction, published in English. Seven studies in total were included in our review including two pre-clinical studies. A meta-analysis was performed on three outcomes included commonly in at least two studies. Among the different parameters assessed were, Erection Hardness Score (EHS), Peak Systolic Velocity in cavernosal artery (PSV) and the Sexual Health Inventory for Men (SHIM) score.

RESULTS

A clear benefit was noted for intracavernosal injection (ICI) of botulinum toxin (BoNT-A) on PSV with a mean difference (MD) of 10.82 [4.99, 16.65] and a heterogeneity of I2=61%. EHS results favored BoNT-A as well over placebo with a MD of 0.7 [0.47, 0.93] and a heterogeneity of I2=94%. As for SHIM score, with a heterogeneity of I2=85%, no statistically significant difference was found (MD 0.58 [-0.03, 1.20]).

CONCLUSION

Our review and meta-analysis have shown statistical significance for the benefit of BoNT-A in terms of EHS and PSV. However, this statistical significance should be interpreted in the light of the given limitations: small sample size, heterogeneity in data collection, patient selection bias, and clinical significance of the measured differences. ICI of BoNT-A should currently be limited to clinical studies to further elucidate its clinical benefit.

Current Techniques for the Objective Measures of Erectile Hardness

INTRODUCTION

One of the most discussed topics in the urology provider's office is that of the male penile erection. Moreover, this is also a frequent basis for consultation by primary care practitioners. As such, it is essential that urologists are familiar with the various means by which the male erection may be evaluated.

OBJECTIVES

This article describes several techniques presently available that may serve to objectively quantify the rigidity and hardness of the male erection. These techniques are meant to bolster information gathered from the patient interview and physical examination to better guide patient management.

METHODS

An extensive literature review was performed examining publications in PubMed on this subject, including corresponding contextual literature.

RESULTS

While validated patient questionnaires have been routinely employed, the urologist has many additional means available to uncover the extent of the patient's pathology. Many of these tools are noninvasive techniques that involve virtually no risk to the patient and take advantage of pre-existing physiologic properties of the phallus and its blood supply to estimate corresponding tissue stiffness. Specifically, Virtual Touch Tissue Quantification which precisely quantifies axial and radial rigidity, can provide continuous data on how these forces change over time, thus providing a promising comprehensive assessment.

CONCLUSION

Quantification of the erection allows for the patient and provider to assess response to therapy, aids the surgeon in choice of appropriate procedure, and guides effective patient counseling regarding expectation management. Rohrer GE, Premo H, Lentz AC. Current Techniques for the Objective Measures of Erectile Hardness. Sex Med Rev 2022;XX:XXX-XXX.

Transpelvic Magnetic Stimulation Enhances Penile Microvascular Perfusion in a Rat Model: A Novel Interventional Strategy to Prevent Penile Fibrosis after Cavernosal Nerve Injury

PURPOSE

Penile microvascular dysfunction is a known contributor to erectile dysfunction (ED) and penile fibrosis has been shown to impair microvascular perfusion (MVP). Our objectives were to: (i) determine beneficial effects of TPMS to modulate penile MVP, (ii) determine its mechanism, (iii) evaluate impact of cavernosal nerve injury (CNI) on penile MVP, and (iv) determine time-course of cavernosal tissue elastin changes after CNI in rats.

MATERIALS AND METHODS

Adult male rats (n=5) were anesthetized and subjected to TPMS (13%, 15%, and 17%) and MVP changes were recorded using laser speckle contrast imaging (LSCI). Another group of male rats were subjected to either bilateral cavernosal nerve injury (CNI; n=7) or sham surgery (n=7). After recovery, animals were monitored for MVP using LSCI before and after TPMS. Rat penile tissues were harvested and analyzed for fibrosis using a marker for elastin.

RESULTS

Rat TPMS resulted in a stimulus dependent increase in MVP; maximal perfusion was observed at 17%. L-N(G)-Nitroarginine methyl ester (L-NAME) resulted in a marked decrease in TPMS induced MVP increase (393.33 AU vs. 210.67 AU). CNI resulted in 40% to 50% decrease in MVP. CNI produced a remarkable increase in elastin deposits that are noticeable throughout the cavernosal tissues post injury.

CONCLUSIONS

TPMS is a novel and non-invasive intervention to improve penile MVP after CNI. Potential application includes treatment of ED and sexual function preservation following cancer treatment, possibly through improved penile hemodynamics that might help prevent penile hypoxia and fibrosis.

Complication Rates in Patients Using Intracavernosal Injection Therapy for Erectile Dysfunction With or Without Concurrent Anticoagulant Use-A Single-Center, Retrospective Pilot Study

Background

Intracavernosal injection therapy (ICI) is an effective intervention used to treat erectile dysfunction (ED). It has been proposed that caution should be exercised when prescribing ICI to patients currently taking anticoagulants (AC) due to the theoretical increased risk of bleeding, however, there is limited literature describing complication rates of actively anticoagulated patients utilizing ICI.

Aim

We sought to determine whether there was a difference in bleeding and other complications in a cohort of patients using ICI therapy with or without concurrent AC use.

Methods

We reviewed our institutional electronic health record and identified 168 patients who were seen in our clinic from January to August 2020 who had either currently or previously utilized ICI therapy for ED treatment. These patients were surveyed regarding their ICI therapy as well as given the erectile dysfunction inventory for treatment satisfaction questionnaire. Data from 85 patients was obtained; 43 concurrently using AC during ICI therapy and 42 with no AC use. Fisher's exact test for categorical variables and a 2-tailed t-test were used with P < .05 considered to be significant.

Outcome

Documented bleeding events (eg, bruising, hematoma), complications, and mean erectile dysfunction inventory for treatment satisfaction scores were compared between the 2 groups.

Results

There were more absolute bleeding complications in the AC group vs the no AC group, with 3 of 43 AC patients (7%, 95% confidence interval: 2.4–18.6) and 0/42 no AC patients (0%, 95% confidence interval: 0–8.4) experiencing some type of bleeding complication on ICI. However, there was no statistically significant difference found in overall or stratified documented bleeding events and complications between the 2 groups.

Clinical Implications

Patients with concurrent AC usage on ICI therapy reported a higher rate of absolute bleeding complications than our non-AC group.

Strengths and Limitations

The strength of this study is addressing question of safety of ICI therapy in patients with concurrent AC usage. Limitations include single-center retrospective study design and underpowered sample size limiting confidence with which conclusions from data should guide future patient counseling regarding ICI risks.

Conclusion

Findings from a single-center cohort of patients suggest that ICI therapy may be a safe and effective treatment modality for ED in patients with concurrent anticoagulant usage, however, given the higher rate of absolute bleeding events in our AC cohort, future assessment in a higher-powered study is warranted in determining a more accurate estimation of risk or propensity for bleeding complications in patients on AC using ICI therapy.

Blum KA, Mehr JP, Green T, et al. Complication Rates in Patients Using Intracavernosal Injection Therapy for Erectile Dysfunction With or Without Concurrent Anticoagulant Use—A Single-Center, Retrospective Pilot Study. Sex Med 2022;10:100535.

The Sexual Goals of Metoidioplasty Patients and Their Attitudes Toward Using PDE5 Inhibitors and Intracavernosal Injections as Erectile Aids

BACKGROUND

Following metoidioplasty, transmen (TM) experience sexual function challenges including erectile dysfunction, which is typically treated in cisgender men with phosphodiesterase-5 inhibitors (PDE5i) and intracavernosal injections (ICI).

AIM

We aim to evaluate sexual function post-metoidioplasty and explore attitudes toward using PDE5i and ICI as potential erectile aids METHODS: All patients who had metoidioplasty completed at the Gender Surgery Program in Vancouver, British Columbia were contacted. Participants completed an electronically accessible self-constructed questionnaire consisting of 39 items on erectile function, orgasm, and penetrative intercourse which also captured Erection Hardness Scores (EHS). Data were analyzed via t-test and 1-way ANOVA.

OUTCOMES

Our outcomes were the importance of erectile function, ability to orgasm, penetrative intercourse, and attitudes towards using PDE5i and ICI post-metoidioplasty.

RESULTS

Fifteen out of 22 patients completed the survey (median age 32 years). Most had metoidioplasty within the past 2 years. The participants ranked the ability to orgasm and to achieve or maintain erections significantly higher than penetrative intercourse (P <.001, P =.005 respectively). Most participants reported facing challenges with penetrative intercourse (87%) and erectile function (80%). In contrast, a smaller proportion reported challenges with orgasm (33%). With regards to EHS, 83% of participants described their erections as either "larger but not hard," or "hard but not hard enough for penetration." A total of 47% of the participants had previously tried PDE5i, but none had used ICI. Although 87% were willing to use PDE5i, only 40% were willing to try ICI to improve their erections. Patients reported lack of knowledge and understanding among primary care physicians as barriers to accessing treatment for sexual dysfunction.

CLINICAL TRANSLATION

The results of this study can facilitate decision making for TM undergoing genital gender-affirmation surgery and provide potential options for improving erectile function post surgery.

STRENGTHS & LIMITATIONS

This study represents the first assessment of sexual function and use of erectile aids in post-metoidioplasty patients. The results of this study are limited by the small sample size and enrolment from a single surgical center.

CONCLUSION

Metoidioplasty patients surveyed fail to achieve a fully rigid erection without treatment, typically retain the ability to orgasm, and are generally willing to try PDE5i. Khorrami A, Kumar S, Bertin E, et al. The Sexual Goals of Metoidioplasty Patients and Their Attitudes Toward Using PDE5 Inhibitors and Intracavernosal Injections as Erectile Aids. Sex Med 2022;10:100505.

Accurate and time‐saving, two‐step intracavernosal injection procedure to diagnose psychological erectile dysfunction

Background

The recognition of the erectile dysfunction pathogenesis is essential to identify the appropriate erectile dysfunction management. As vascular erectile dysfunction could be a manifestation of a systemic arterial damage, the watershed in the erectile dysfunction diagnostic framework is the discrimination between psychological erectile dysfunction and vascular erectile dysfunction. However, reliable tools to directly diagnose psychological erectile dysfunction are currently lacking.

Objective

To identify which parameters could predict psychological erectile dysfunction. Moreover, we suggest a new intracavernosal injection procedure to optimize the erectile dysfunction diagnostic workup.

Materials and methods

A retrospective, real‐world analysis was carried out including all men who underwent intracavernosal injection procedure at the Modena Andrology Unit from 2018 to 2021. A first intracavernosal injection procedure with 5 µg of prostaglandin E‐1 (PGE‐1) was performed. In the absence of a full drug‐induced erection (immediate or delayed), an echo‐color Doppler penile evaluation after administration of PGE‐1 10 µg was conducted, measuring intracavernosal blood flows, to document a possible vascular etiology. Hormonal evaluations were performed.

Results

Out of 179 enrolled patients, 70.4% showed psychological erectile dysfunction, 21.7% vascular erectile dysfunction, and 7.8% hormonal genesis. Multinomial logistic regression analysis identified absence of cardiovascular disease (p = 0.017), presence of spontaneous morning erections (p = 0.018), and normal penile erections with masturbation (p = 0.035) as predictors of psychological erectile dysfunction. Clinically, normal intracavernosal injection test response was detected in 86 patients and abnormal response in 93 subjects. Among the latter, 54 patients experienced a delayed response. The combination of intracavernosal injection test with late penile erections evaluation was able to diagnose psychological erectile dysfunction (sensitivity 97%, specificity 100%), avoiding unnecessary retesting.

Discussion

We propose a two‐step intracavernosal injection procedure that allows to recognize psychological erectile dysfunction with a high sensitivity/specificity, saving costs and time, and limiting adverse events. Moreover, the presence of spontaneous morning erections and valid penile erections after masturbation could guide the diagnostic workup, indirectly identifying those patients deserving of a deeper evaluation of vascular health.

Adjuvant daily therapy with L-arginine 2,500 mg and tadalafil 5 mg increases efficacy and duration of benefits of low-intensity extracorporeal shock wave therapy for erectile dysfunction: A prospective, randomized, single-blinded study with 1-year follow-up

Purpose

To investigate a therapeutic protocol for erectile dysfunction (ED) based on the combination of low-intensity extracorporeal shock wave therapy (Li-ESWT), tadalafil, and L-arginine.

Materials and Methods

Recruited patients completed the International Index of Erectile Function erectile function domain (IIEF-EF) and the Erection Hardness Score (EHS) questionnaires at baseline and were randomly assigned in two groups: A (treatment group) and B (control group). Men in both groups received six weekly applications of Li-ESWT. Group A was prescribed adjuvant oral therapy with tadalafil 5 mg and L-arginine 2,500 mg. Follow-up visits were scheduled 1, 6, and 12 months after the last Li-ESWT application. At each follow-up visit, the IIEF-EF and EHS questionnaires were administered again. The main outcome measures were the changes from baseline to every follow-up visit in IIEF-EF and EHS scores.

Results

The mean IIEF-EF score in group A was 16.0±4.0, 24.8±3.4, 23.3±4.6, and 21.6±5.5 at baseline, 1, 6, and 12 months of follow-up, respectively, whereas in group B the mean IIEF-EF score was 16.5±4.1, 22.7±4.2, 21.5±4.5, and 19.5±4.9, respectively. We reported an increase in the mean EHS score in group A from 2.07±0.72 at baseline to 3.39±0.59, 3.17±0.67, and 2.98±0.72 at 1, 6, and 12 months, respectively, and in group B from 2.12±0.80 at baseline to 3.07±0.78 and 2.95±0.76 at 1 and 6 months, respectively.

Conclusions

Adjuvant daily therapy with L-arginine 2,500 mg and tadalafil 5 mg was safe and effective in increasing the efficacy and the duration of benefits of Li-ESWT.

Stem cell therapy and diabetic erectile dysfunction: A critical review

Erectile dysfunction (ED) has been identified as one of the most frequent chronic complications of diabetes mellitus (DM). The prevalence of ED is estimated to be about 67.4% in all DM cases worldwide. The pathophysiological process leading to ED involves endothelial, neurological, hormonal, and psychological factors. In DM, endothelial and neurological factors play a crucial role. Damages in the blood vessels and erectile tissue due to insulin resistance are the hallmark of ED in DM. The current treatments for ED include phosphodiesterase-5 inhibitors and penile prosthesis surgery. However, these treatments are limited in terms of just relieving the symptoms, but not resolving the cause of the problem. The use of stem cells for treating ED is currently being studied mostly in experimental animals. The stem cells used are derived from adipose tissue, bone, or human urine. Most of the studies observed an improvement in erectile quality in the experimental animals as well as an improvement in erectile tissue. However, research on stem cell therapy for ED in humans remains to be limited. Nevertheless, significant findings from studies using animal models indicate a potential use of stem cells in the treatment of ED.

Complete study for erectile dysfunction (CompED) improving diagnosis and treatment decision-making

Erectile dysfunction is a condition associated with increasing age. Patient evaluation and management should follow a comprehensive, stepwise approach. The aim of this article was to report our experience with the complete study for erectile dysfunction, including intracavernous injection rigidity test, biothesiometry and colour duplex Doppler ultrasound. Data were collected and analysed prospectively. The primary end point was to determine whether treatment decision-making was eased by the CompED test. Secondary end points were to establish which clinical variables prior to the study could impact the results of the CompED test, to finally improve patient selection for the study. 187 patients were recruited, 31.2% of the patients had an axial rigidity below 50%, 28.5% had a peak systolic velocity <25 cm/s, 13.2% had an end-diastolic velocity >5cm/s and 27.5% had an abnormal biothesiometry. The factors that best predicted an abnormal result in any of the tests were age >70 years, IIEF domain A < 14 points, and previous radical prostatectomy or radiotherapy. The CompED test stands as a new alternative for the evaluation of patients with erectile dysfunction, being less time consuming, aiding in a more accurate determination of the aetiology and guiding treatment decision-making.

Visual Side Effects Linked to Sildenafil Consumption: An Update

Phosphodiesterase type 5 (PDE5) inhibitors such as Viagra^® (sildenafil citrate) have demonstrated efficacy in the treatment of erectile dysfunction (ED) by inducing cyclic guanosine monophosphate (cGMP) elevation followed by vasodilation and increased blood flow. It also exerts minor inhibitory action against PDE6, which is present exclusively in rod and cone photoreceptors. The effects of sildenafil on the visual system have been investigated in a wide variety of clinical and preclinical studies due to the fact that a high dose of sildenafil may cause mild and transient visual symptoms in some patients. A literature review was performed using PubMed, Cochrane Library and Clinical Trials databases from 1990 up to 2020, focusing on the pathophysiology of visual disorders induced by sildenafil. The aim of this review was not only to gather and summarize the information available on sildenafil clinical trials (CTs), but also to spot subpopulations with increased risk of developing undesirable visual side effects. This PDE inhibitor has been associated with transient and reversible ocular side effects, including changes in color vision and light perception, blurred vision, photophobia, conjunctival hyperemia and keratitis, and alterations in the electroretinogram (ERG). Sildenafil may induce a reversible increase in intraocular pressure (IOP) and a few case reports suggest it is involved in the development of nonarteritic ischemic optic neuropathy (NAION). Reversible idiopathic serous macular detachment, central serous retinopathy and ERG disturbances have been related to the significant impact of sildenafil on retinal perfusion. So far, sildenafil does not seem to cause permanent toxic effects on chorioretinal tissue and photoreceptors as long as the therapeutic dose is not exceeded and is taken under a physician’s direction to treat a medical condition. However, the recreational use of sildenafil can lead to harmful side effects, including vision changes.

Alternative Treatment for Erectile Dysfunction: a Growing Arsenal in Men's Health

PURPOSE OF REVIEW

To highlight and review encouraging preliminary studies behind several alternative products and interventions for erectile dysfunction (ED).

RECENT FINDINGS

Alternative treatments for ED are becoming more prevalent with increased consumer interest. "Natural" products are sold online, and numerous clinics offer various off-label and investigational interventions. These alternative treatments have demonstrated varying degrees of efficacy in randomized trials and meta-analyses, but none of these interventions has robust enough evidence to be considered first-line therapy. These treatments may find a role in combination with guideline treatments or may be used in novel penile rehabilitation research protocols. With growing interest in alternative treatment for men's health, an awareness of the literature is imperative for patient counsel. Alternative treatments, like L-arginine, have a growing body of evidence for efficacy in combination with PDE5i, and low-intensity shock wave therapy and stem cell therapy continue to demonstrate encouraging outcomes in ED trials.

Drug delivery options and therapeutic advances in the management of erectile dysfunction

INTRODUCTION

Erectile dysfunction (ED) is defined as the inability to achieve or maintain an erection sufficient for satisfactory sexual performance. It is estimated that 20-30% of adult men will have at least one episode of ED during their lifetime and the prevalence increases with age. ED is known to have significant negative psychological implications for men, resulting in impaired functional status and a greater prevalence of anxiety and depression.

AREAS COVERED

Medications for the treatment of erectile dysfunction largely revolve around oral, injection, and topical therapies. Though all three modalities are widely used, each delivery option has its own advantages and specific indications. Likewise, there are several new developing treatments for ED that may change the landscape of treatment. The goal of this review is to summarize contemporary drug delivery options used in the treatment of ED and highlight future promising pharmacological developments.

EXPERT OPINION

There are a myriad of new developments on the horizon including new PDE5Is and drug targets, nanotechnology enhancements, stem cell and gene therapy, shockwave therapy, and platelet-rich plasma injections. These are all promising new methods to not only treat ED but also to address the pathology and prevent or eliminate further damage.

Revisiting the Regenerative Therapeutic Advances Towards Erectile Dysfunction

Erectile dysfunction (ED) is an inability to attain or maintain adequate penile erection for successful vaginal intercourse, leading to sexual and relationship dissatisfaction. To combat ED, various surgical and non-surgical approaches have been developed in the past to restore erectile functions. These therapeutic interventions exhibit significant impact in providing relief to patients; however, due to their associated adverse effects and lack of long-term efficacy, newer modalities such as regenerative therapeutics have gained attention due to their safe and prolonged efficacy. Stem cells and platelet-derived biomaterials contained in platelet-rich plasma (PRP) are thriving as some of the major therapeutic regenerative agents. In recent years, various preclinical and clinical studies have evaluated the individual, as well as combined of stem cells and PRP to restore erectile function. Being rich in growth factors, chemokines, and angiogenic factors, both stem cells and PRP play a crucial role in regenerating nerve cells, myelination of axons, homing and migration of progenitor cells, and anti-fibrosis and anti-apoptosis of damaged cavernous nerve in corporal tissues. Further, platelet-derived biomaterials have been proven to be a biological supplement for enhancing the proliferative and differentiation potential of stem cells towards neurogenic fate. Therefore, this article comprehensively analyzes the progresses of these regenerative therapies for ED.

Current approaches to the diagnosis of vascular erectile dysfunction

Vascular erectile dysfunction (ED) is closely related to cardiovascular events, and early diagnosis of vascular ED may be helpful to predict the occurrence of cardiovascular events and improve prognosis. At present, there are many approaches to diagnose ED, but each method has its advantages and limitations. This study retrospectively reviewed all available literature focusing on the diagnosis of vascular ED through a systematic PubMed and EMBASE search. According to the different application scenarios, the main methods for the diagnosis of vascular ED are divided into four categories. Intra-cavernous injection of vasoactive drugs is the earliest method used in the diagnosis of vascular ED and is a basic test. For the diagnosis of arterial ED, color duplex Doppler ultrasound, selective penile angiography, magnetic resonance imaging, and computed tomography are more commonly used. While for the diagnosis of venous ED, shear wave elastography, dynamic infusion cavernosometry and cavernosography are more accurate. Endo-peripheral arterial tonometry (PAT) has also been used to detect vascular endothelial function. Although various existing examinations are widely used for the evaluation of vascular ED, they still have some shortcomings, such as invasiveness, contingency, high false positive (negative) rate. New methods of long-term dynamic detection are needed.

Novel Emerging Therapies for Erectile Dysfunction

Currently, several treatments exist for the improvement of erectile dysfunction (ED). These include medical therapies such as phosphodiesterase type 5 inhibitors (PDE5-Is), invasive methods such as intracavernosal injection therapy of vaso-active substances, vacuum erection devices, and penile prosthesis implants. However, the percentage of patients that are unresponsive to available treatments and who drop out from treatments remains high. Current evidence reveals that the pathogenesis of ED is related to multiple factors including underlying comorbidities, previous surgery, and psychological factors. Diverse approaches using novel molecular pathways or new technologies have been tested as potential therapeutic options for difficultto-treat ED populations. Melanocortin receptor agonist, a centrally acting agent, showed promising results by initiating erection without sexual stimulation in non-responders to PDE5-Is. Recent clinical and pre-clinical studies using human tissues suggested that new peripherally acting agents including the Max-K channel activator, guanylate cyclase activator, and nitric oxide donor could be potential therapies either as a monotherapy or in combination with PDE5-Is in ED patients. According to several clinical trials, regeneration therapy using stem cells showed favorable data in men with diabetic or post-prostatectomy ED. Low-intensity shock wave therapy also demonstrated promising results in patients with vasculogenic ED. There are growing evidences which suggest the efficacy of these emerging therapies, though most of the therapies still need to be validated by well-designed clinical trials. It is expected that, should their long-term safety and efficacy be proven, the emerging treatments can meet the needs of patients hitherto unresponsive to or unsatisfied by current therapies for ED.

Pharmacology and perspectives in erectile dysfunction in man

Penile erection is a perfect example of microcirculation modulated by psychological factors and hormonal status. It is the result of a complex neurovascular process that involves the integrative synchronized action of vascular endothelium; smooth muscle; and psychological, neuronal, and hormonal systems. Therefore, the fine coordination of these events is essential to maintain penile flaccidity or allow erection; an alteration of these events leads to erectile dysfunction (ED). ED is defined as the consistent or recurrent inability of a man to attain and/or maintain a penile erection sufficient for sexual activity. A great boost to this research field was given by commercialization of phosphodiesterase-5 (PDE5) inhibitors. Indeed, following the discovery of sildenafil, research on the mechanisms underlying penile erection has had an enormous boost, and many preclinical and clinical papers have been published in the last 10 years. This review is structured to provide an overview of the mediators and peripheral mechanism(s) involved in penile function in men, the drugs used in therapy, and the future prospective in the management of ED. Indeed, 30% of patients affected by ED are classified as "nonresponders," and there is still an unmet need for therapeutic alternatives. A flowchart suggesting the guidelines for ED evaluation and the ED pharmacological treatment is also provided.

A Review of Current and Emerging Therapeutic Options for Erectile Dysfunction

Contemporary treatment algorithms for erectile dysfunction (ED) involve the use of medical therapies such as phosphodiesterase type 5 (PDE5) inhibitors and intracavernosal injection therapy of vasoactive agents, as well as vacuum erection devices and penile prosthesis implants in medically refractory cases. However, the current therapeutic options only address the symptoms of ED and not the underlying pathogenesis that results in ED. Newer and novel ED therapies aspire to reverse ED conditions by preventing cavernosal fibrosis, promoting endothelial revascularization and modulating various neuro-hormonal pathways. Regenerative therapeutic strategies such as low-intensity shock wave, gene and cellular-based therapies, and penile transplants are designed to improve penile hemodynamics and revitalize the cavernosal smooth muscle to mitigate and/or reverse underlying ED. This state-of-art article evaluates current and emerging therapeutic options for ED.

End-to-side Somatic-to-autonomic Nerve Grafting to Restore Erectile Function and Improve Quality of Life After Radical Prostatectomy

BACKGROUND

Radical prostatectomy (RP) is recommended for the treatment of men with clinically localised prostate cancer. However, RP is associated with a high incidence of erectile dysfunction (ED), which can impact the quality of life (QoL) significantly.

OBJECTIVE

To evaluate the effectiveness of end-to-side nerve grafting surgery to restore erectile function and improve sexual QoL in men with ED after RP.

DESIGN, SETTING, AND PARTICIPANTS

A retrospective review of a single-centre experience of nerve grafting in men with ED following RP was performed. Seventeen men had surgery between March 2015 and October 2017 in Melbourne, Australia, which fulfilled study inclusion and exclusion criteria.

INTERVENTION

Microsurgical bilateral end-to-side nerve grafts from a selective fascicular neurotomy of the femoral nerve to the penile corpora cavernosa.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Results were serially measured utilising the International Index of Erectile Function (IIEF-5) and the sexual domain of Expanded Prostate Cancer Index Composite (EPIC-26). The proportion and 95% confidence interval (CI) of men recovering sexual function following nerve grafting were determined.

RESULTS AND LIMITATIONS

All patients had ED following their RP. Median age at nerve grafting was 64yr (interquartile range [IQR] 60-66yr). Median time between nerve- and non-nerve-sparing RP, and nerve grafting was 2.4 (IQR 2.1-3.1) and 2.2 (IQR 1.7-5.1)yr, respectively. Median follow-up was 18 (IQR 15-24) mo. At 12mo after nerve grafting, 71% (95% CI 44-90%) of patients had erectile function recovery sufficient for satisfactory sexual intercourse, and 94% (95% CI 71-99%) and 82% (95% CI 57-96%) had clinically significant improvements in sexual function and reduced bother, respectively. There were two minor wound infections. Limitations include the retrospective study design.

CONCLUSIONS

End-to-side nerve grafting restored erectile function in 71% of men with ED following RP, supporting previous findings. Of the men, 94% had clinically relevant improvements in sexual QoL. We recommend multicentre implementation of post-RP nerve grafting into clinical practice with appropriate data collection to confirm its efficacy and feasibility.

PATIENT SUMMARY

We provide confirmatory evidence that end-to-side nerve grafting surgery restored erectile function and improved sexual quality of life in, respectively, 71% and 94% of men with erectile dysfunction following radical prostatectomy.

Recent advances in the understanding and management of erectile dysfunction

Erectile dysfunction (ED) is important to a man’s well-being and health, since it not only affects the individual but also causes strain on a couple’s lifestyle and relationship. There are multiple non-invasive treatments that exist for ED including lifestyle changes, oral medications (phosphodiesterase type 5 inhibitors), vacuum-assisted erectile devices, and intraurethral suppositories. While lifestyle changes and oral medications are typically first-line treatments for ED, more-invasive treatments including intracavernosal injections and surgically implanted prosthetic devices may be required for the management of complex cases. Additionally, novel therapies are currently being developed, and future treatment options may include shock-wave therapy, external prosthetic devices, and injection of stem cells or platelet-rich plasma. The current manuscript seeks to highlight advances in management and may eventually alter the treatment paradigm to allow more-inclusive care pathways.

Impact of Surgical Treatment of Penile Fracture on Sexual Function

OBJECTIVE

To conduct a comprehensive assessment of sexual function of patients undergoing surgical treatment of penile fracture (PF), covering psychological aspects related to trauma.

METHODS

Patients undergoing surgical treatment of PF from January 2014 to August 2017 were followed-up in our department for at least 6 months. The patients underwent a detailed clinical follow-up, including physical examination and were interviewed about any evidence of erectile dysfunction, penile nodules, or curvature acquired after surgery, besides psychological sexual problems.

RESULTS

A total of 58 patients conducted the follow-up. The mean age was 38.5 years (range: 18-66 years). Eight (13.7%) patients complained of penile curvature after surgery. Postoperative erectile function was recovered after 6 months in 50 (86.2%) cases. After the last evaluation at 18 months, only 1 patient developed persistent erectile dysfunction (ED) and color duplex Doppler ultrasound excluded a vascular etiology. Psycho-sexual evaluations showed that 45 (77.5%) patients feared a new episode of PF. Changes in sexual habits, such as avoiding vigorous sexual intercourse, was reported by 40 (68.9%) patients. Finally, patients with performance anxiety and those who reported a negative impact on sexual life were more susceptible to the development of ED (P = .0337 and P = .0418, respectively).

CONCLUSION

Sexual complications after surgical treatment of PF are unusual but may occur in the late postoperative period and should be treated. Psychological sequela is very common, causing fear of recurrence and psychogenic ED, resulting in negative impact on the sexual life of these patients, which should be monitored closely.

Diabetic autonomic neuropathy resulting in sexual dysfunction

Although diabetic autonomic neuropathy (DAN), a complication associated with diabetes, is increasing in prevalence, it is often overlooked. Knowledge regarding the development and progression of this complication is limited. NPs are in a key position to prevent complications of DAN, including sexual dysfunction, in this vulnerable population.

Urology as rehabilitation medicine: a literature review

As a urologist, we usually encounter with two representative functional behaviors, namely, voiding and sexual function. These are not only important but also complex and synchronized so if these functions are impaired, patients need active functional rehabilitation to recover. These functional impairments should be recognized and corrected early because they could not only cause direct damage to the affected functions but also have harmful consecutive consequences such as kidney damage due to voiding abnormality and self-esteem damage due to decreased sexual function. Numerous rehabilitative methods are currently available, which help minimize the negative effects of these functional impairments. In terms of voiding function, pelvic floor muscle exercise, biofeedback, functional magnetic stimulation, neuromodulation, and clean intermittent self-catheterization are representative rehabilitation modalities. In case of children, extra-attention should be paid because this might affect their entire life. In impairment of sexual function, early intervention to maintain male erection is the main target of rehabilitation to prevent corporal fibrosis and penile deformity and increase recovery chance in patients who underwent radical prostatectomy or major surgery. In this review, we will elucidate various rehabilitation methods in urology to further increase our understanding of the rehabilitative characteristics of urology and widen our view of rehabilitation medicine.

Medical treatment of erectile dysfunction: too many medical prescriptions?

Erectile dysfunction (ED) is a worldwide commonly reported condition; epidemiological data showed a prevalence ranging from 2.3 to 53.4% within different population subsets. In this context, the advent of phosphodiesterase type 5 inhibitors (PDE5is) in the second mid of 1990s has deeply changed the treatment scenario of this bothersome condition. Being user-friendly compounds with an excellent overall safety profile, PDE5is emerged as the first-line treatment for ED, thus overcoming topical alprostadil and intracavernous injections (ICIs). However, available data on treatment-utilization patterns and medical prescriptions of PDE5is showed a range of as wide as 22-78% of patients reporting to purchase PDE5is even without a proper medical prescription. Moreover, an increase in the recreational use of PDE5is among young men has been observed in the last decades, with a worrisome diffusion of potential health-risky behaviours associated with this habit. Indeed, treatment of ED should carefully follow internationally based clinical guidelines to avoid inappropriate drug prescriptions, which may eventually expose treated patients to drug-related side effects. Thereof, a careful assessment of the so-called modifiable and reversible ED risk factors along with a patient-tailored screening for potential contraindications to the treatment itself should be performed in every case. Lastly, although conclusive data still lack, the potential association between life-risky PDE5is side effects (i.e. cardiovascular adverse events, melanoma skin cancer and worsening of prostate cancer outcomes) should be carefully taken into account when counselling patients for ED treatment.