The Basic Science Behind Low-Intensity Extracorporeal Shockwave Therapy for Erectile Dysfunction: A Systematic Scoping Review of Pre-Clinical Studies

Androgens and erectile dysfunction: from androgen deficiency to treatment

INTRODUCTION

Androgens play important roles in regulating the growth and development of the male reproductive system and maintaining libido and erectile function. The specific mechanisms by which androgen deficiency leads to erectile dysfunction (ED) are not yet fully understood.

OBJECTIVES

To understand the mechanisms and treatment of androgen deficiency-related ED.

METHODS

A literature search in the past 10 years was conducted in PubMed and Google Scholar to determine the effects of androgen deficiency on erectile function and the treatment of androgen deficiency.

RESULTS

Androgen deficiency can be caused by hypothalamic-pituitary lesions and injuries, testicular-related diseases and injuries, endocrine and metabolic disorders, the side effects of medication, and age. Androgen deficiency can lead to ED by inhibiting the NOS/NO/cGMP pathway (nitric oxide synthase/nitric oxide/cyclic guanosine monophosphate) and altering the expression of ion channel proteins, as well as by inducing oxidative stress, death, and fibrosis in penile corpus cavernosum cells. Testosterone replacement therapy is effective at improving the serum testosterone levels and erectile function in patients with androgen deficiency. For patients who need to maintain a low androgenic state, erectile function can be improved by lifestyle changes, treatment with phosphodiesterase type 5 inhibitors, low-intensity extracorporeal shock wave therapy, and stem cell therapy.

CONCLUSIONS

Androgen deficiency can affect the structure and function of the penile corpus cavernosum, leading to ED. Areas of further study include how androgen replacement therapy can improve erectile function and how to improve the maintenance of erectile function in patients with hypoandrogenic status.

A primer on the restorative therapies for erectile dysfunction: a narrative review

INTRODUCTION

Erectile dysfunction (ED) is a common condition that affects millions worldwide. Patients and urologists alike are seeking alternative therapies that can provide long-lasting results in the treatment of ED. This review provides a comprehensive overview of restorative treatments available for ED, such as platelet-rich plasma, stem cell therapy, and shockwave therapy.

OBJECTIVE

The aim of this narrative review is to provide a primer for urologists and general practitioners on the basics of implementing ED restorative therapies in their practice.

METHODS

The PubMed, MEDLINE, and Google Scholar databases were searched for articles in the English language through August 31, 2023, that included key terms such as "erectile dysfunction," "restorative therapy," "shockwave therapy," "platelet-rich plasma," "stem cell therapy," and "stromal vascular fraction." Reference lists of selected studies were manually reviewed to find articles not identified by the initial database search.

RESULTS

Shockwave therapy has demonstrated effectiveness in treating ED, with devices like the Medispec ED1000 and Storz Duolith showing statistically significant improvements in patient scores for International Index of Erectile Function (IIEF)-Erectile Function scores in clinical trials. In reported studies of platelet-rich plasma injections, a substantial percentage of patients reached a minimal clinically important difference in the IIEF-Erectile Function scale after treatment. Studies of ED treatment with stem cell therapy, while limited and with small sample sizes, have demonstrated encouraging improvements in patient scores for the abridged 5-item version of the IIEF after treatment.

CONCLUSION

Shockwave, platelet-rich plasma, and stem cell therapies are important, novel, noninvasive restorative treatments for ED that can provide relief for patients wishing to avoid a more invasive approach. While these therapies have shown promising results in clinical trials, more research is required to establish them as standardized and efficacious options in the management of ED.

Variations in Low Intensity Shockwave Treatment Protocols for Erectile Dysfunction: A Review of the Literature and Guide to Offering Treatment

Low-intensity shockwave therapy (LiSWT) for erectile dysfunction (ED) continues to gain popularity in both clinical practice and the academic literature. The majority of trials and meta-analysis studies have shown LiSWT to be low risk with a trend toward positive improvements in International Index of Erectile Function (IIEF) scores. However, there is still debate over the clinical utility of LiSWT and there is no agreed upon optimal treatment protocol. In this review article we summarize published meta-analysis studies of LiSWT for ED, and review the treatment protocols from randomized sham-control trials published in the last 10 years. We found the most common device settings were an energy of 0.09 mJ/mm² and a frequency of 5 Hz. Shock number and location varied, but the most common protocol was 1,500 shocks per session, with 900 shocks to the penis (shaft, base, or hilum) and 600 shocks to the proximal corpora/crura. Protocols ranged from 4 to 12 treatment sessions. We also describe our institutional experience with LiSWT, including patient counseling and treatment protocol.

Long-term outcomes of extracorporeal shock wave therapy for acute Peyronie's disease: a 10-year retrospective analysis

The aim of this paper was to describe the long-term outcomes of extracorporeal shock wave therapy (ESWT) in patients with acute Peyronie'disease (PD). An observational retrospective study was conducted in men with acute PD who underwent ESWT between 2009-2013 at a single institution. ESWT protocol consisted of 1 session (3000 shock waves, 0.10-0.25 mJ/mm^2, 4-6 Hz) per week for 4 weeks. Penile pain was chosen as the primary outcome. Penile curvature angle, erectile function, and satisfaction with ESWT were selected as secondary long-term outcomes. A total of 194 patients were included. The mean follow-up duration after ESWT was 125.6 months. Mean penile curvature worsened significantly at 3 months (18.3 vs. 21.5 degrees; p = 0.023) and 12 months (21.5 vs. 28.6 degrees; p = 0.001) and stabilized over the long-term (28.6 vs. 28.8 degrees; p = 0.335). Mean penile pain improved significantly at 3 months (6.5 vs. 3.1 points; p < 0.001) and 12 months (3.1 vs. 1.0 points; p = 0.001), remaining stable over time (1.0 vs. 1.0 points; p = 0.074). The mean five-item version of the International Index of Erectile Function (IIEF-5) increased significantly at 3 months (14.5 vs. 17.9 points; p = 0.001), remaining stable at 12 months (17.9 vs. 18.5 points; p = 0.082), and deteriorating in the long-term (18.5 vs. 15.8 points; p = 0.003). A high satisfaction rate with ESWT was recorded at 3 months (92.3%), remaining similar at 12 months (91.2%) and over the long-term (90.2%). No new acute phase and low rate of PD surgery (4.1%) were recorded in the long-term analysis. In patients with acute PD, ESWT seems to be associated with early and persistent relief of penile pain, transient improvement in erectile function, no significant effect on penile curvature, and a high rate of patient satisfaction constant over time.

News and future perspectives of non-surgical treatments for erectile dysfunction

The significant discontinuation rate of available therapies and the paucity of curative options promoted the research on potential novel treatments suitable for erectile dysfunction patients. The aim of this study was to provide a summary of available evidence regarding the news and future perspectives related to the non-surgical treatment of erectile dysfunction. A narrative review of the literature was performed. A comprehensive search in the MEDLINE, Embase, and Scopus databases was done. Papers in English-language, published until April 2022, were included. No chronological restriction was applied. Retrospective and prospective clinical studies, as well as meta-analyses, were considered. Oro-dispersible formulations of phosphodiesterase type 5 inhibitors are particularly indicated in patients who have difficulty in swallowing solid dosage form; in addition, they constitute a discrete route of administration not requiring water. Low-intensity extracorporeal shock wave therapy is indicated in mild vasculogenic erectile dysfunction and in patients with vasculogenic erectile dysfunction poorly responsive to phosphodiesterase type 5 inhibitors. Stem cell therapy, platelet-rich plasma injections, and gene therapy seem promising regenerative treatments for selected patients with erectile dysfunction. Novel oral formulations of drugs commonly used in erectile dysfunction patients have recently become part of standard clinical practice. Regenerative treatments have been emerging in recent years and could become routine curative options in the near future. Further well-designed randomized controlled trials are needed to provide conclusive evidence on this topic and guide appropriate recommendations.

Long-term effects of combination treatment comprising low-intensity extracorporeal shockwave therapy and tadalafil for patients with erectile dysfunction: a retrospective study

This study retrospectively examined the effects of low-intensity extracorporeal shockwave therapy and tadalafil on erectile dysfunction patients. 116 patients got low-intensity extracorporeal shockwave therapy twice weekly for 3 weeks, 5 mg of tadalafil daily for 3 weeks, and adjuvant therapy for 6 months. Group A (1 year), Group B (2 years), Group C (3 years), and Group D (4+ years) were treated patients' follow-up groups. The patients' International Index of Erectile Function-5 (IIEF-5) scores were gathered at the start of treatment via face-to-face interviews and at the end of follow-ups by telephone conversations. IIEF-5 scores and the minimal clinically significant differences were the main outcomes. Mean follow-up length, age, and IIEF-5 scores of the patients were 2 ± 1.16 years, 47.34 ± 12.65 years, and 12.09 ± 3.66 points, respectively. Compared to baseline, treatment increased the median IIEF-5 scores of patients in groups A, B, C, and D by 7 [3-12], 6 [0-8], 7 [1-9], and 6.5 [2.5-10] points, respectively (p = 0.001). 71%, 63%, 65.8%, and 65% of treated patients in groups A, B, C, and D met the minimal clinically significant differences criteria (n = 77). Mild disease patients were 9.14 times more likely to respond to treatment than severe illness patients (OR, 9.14; 95% CI, 1.28-65.46; P = 0.02). Low-intensity extracorporeal shockwave therapy and 5 mg of tadalafil can treat erectile dysfunction for up to 4 years with sustained outcomes. This treatment is optimal for mild illnesses.

Comparison of the efficacy of the early LI-SWT plus daily tadalafil with daily tadalafil only as penile rehabilitation for postprostatectomy erectile dysfunction

This study compares the efficacy of the early low-intensity shock wave therapy (LI-SWT) plus daily tadalafil with daily tadalafil only therapy as penile rehabilitation for postprostatectomy erectile dysfunction in patients with prostate cancer who underwent bilateral interfascial nerve-sparing radical prostatectomy (robotic or open). From April 2019 to March 2021, 165 patients were enrolled, and 80 of them successfully completed this prospective study. Daily tadalafil were administered to all the patients. LI-SWT consisted of a total of six sessions. Each session was performed on days 4, 5, 6, and 7, and on the second and fourth weeks after surgery. Each LI-SWT session consisted of 300 shocks at an energy density of 0.09 mJ/mm2 and a frequency of 120 shocks per minute that were delivered at each of the five treatment points for 15 min. Thirty-nine patients were treated with tadalafil-only (group A) while 41 were treated with tadalafil and LI-SWT simultaneously (group B). At postoperative 6 months, the proportion of patients with erection hardness scores (EHS) ≥ 3 (4/39 vs. 12/41) was significantly higher in group B (p = 0.034), and LI-SWT was the only independent factor for predicting EHS ≥ 3 (OR, 3.621; 95% CI, 1.054-12.437; p = 0.041). There were no serious side effects related to early LI-SWT. Early LI-SWT plus daily tadalafil therapy as penile rehabilitation for postprostatectomy erectile dysfunction is thought to be more efficacious than tadalafil only. Further large-scaled randomized controlled trials will be needed to validate these findings.

Global trends in research on extracorporeal shock wave therapy (ESWT) from 2000 to 2021

BACKGROUND

This study intended to analyze the application of extracorporeal shock wave therapy in medicine and to evaluate the quality of related literature.

METHODS

All publications were extracted from 2000 to 2021 from the Web of Science Core Collection (WoSCC). The literature characteristics were depicted by VOSviewer (version 1.6.15) and the online bibliometric website ( http://bibliometric.com/ ). The future trends and hotspots were conducted by Bibliographic Item Co-occurrence Matrix Builder (version 2.0) and gCLUTO software.

RESULTS

We analyzed 1774 articles corresponding to the criteria for ESWT publications from 2000 to 2021. Most studies were conducted within the United States and China which besides have the most cooperation. The most published research institutions are Chang Gung University, Kaohsiung Chang Gung Memorial Hospital, and Kaohsiung Medical University. Six research hotspots were identified by keyword clustering analysis: Cluster0: The effects of ESWT on muscle spasticity; Cluster1: The application of ESWT in osteoarthritis (OA); Cluster2: Therapeutic effect of ESWT on tendon diseases; Cluster3: Early application of ESWT/ESWL in urolithiasis; Cluster4: The Role of angiogenesis in ESWT and the efficiency of ESWT for penile disease; Cluster5: The Special value of radial extracorporeal shock wave therapy (rESWT).

CONCLUSIONS

A comprehensive and systematic bibliometric analysis of ESWT was conducted in our study. We identified six ESWT-related research hotspots and predicted future research trends. With the gradual increase of research on ESWT, we find that ESWT is used more and more extensively, such in musculoskeletal disease, bone delay union, neurological injury, andrology disorders, lymphedema, and so on. In addition, the mechanism is not destructive damage, as initially thought, but a restorative treatment. Furthermore, delayed union, cellulite, burn, and diabetic foot ulcers may be the future direction of scientific study.

Piezo1 activation induces relaxation of the pudendal artery and corpus cavernosum

Piezo1 channel is a sensor for shear-stress in the vasculature. Piezo1 activation induces vasodilation, and its deficiency contributes to vascular disorders, such as hypertension. In this study, we aimed to determine whether Piezo1 channel has a functional role in the dilation of pudendal arteries and corpus cavernosum (CC). For this, male Wistar rats were used, and the relaxation of the pudendal artery and CC was obtained using the Piezo1 activator, Yoda1, in the presence and absence of Dooku (Yoda1 antagonist), GsMTx4 (non-selective mechanosensory channel inhibitor) and L-NAME (nitric oxide synthase inhibitor). In the CC, Yoda1 was also tested in the presence of indomethacin (non-selective COX inhibitor) and tetraethylammonium (TEA, non-selective potassium channel inhibitor). The expression of Piezo1 was confirmed by Western blotting. Our data show that Piezo1 activation leads to the relaxation of the pudendal artery and CC as the chemical activator of Piezo1, Yoda1, relaxed the pudendal artery (47%) and CC (41%). This response was impaired by L-NAME and abolished by Dooku and GsMTx4 in the pudendal artery only. Indomethacin and TEA did not affect the relaxation induced by Yoda1 in the CC. Limited tools to explore this channel prevent further investigation of its underlying mechanisms of action. In conclusion, our data demonstrate that Piezo1 is expressed and induced the relaxation of the pudendal artery and CC. Further studies are necessary to determine its role in penile erection and if erectile dysfunction is associated with Piezo1 deficiency.

Low-intensity extracorporeal shockwave therapy for diabetic men with erectile dysfunction: A systematic scoping review

BACKGROUND

Erectile dysfunction (ED) is a very common complication in men with diabetes mellitus (DM). Low-intensity extracorporeal shockwave therapy (Li-ESWT) offers a promising nonsurgical treatment option for ED. A systematic scoping review investigating the outcomes of Li-ESWT in diabetic men with ED has not yet been performed.

OBJECTIVES

To systematically review animal and clinical studies related to the use of Li-ESWT for treatment of DM-related ED.

DATA SOURCES

PubMed, Embase, The Cochrane Library, Scopus, and Web of Science were searched, unrestricted by dates or study design.

MATERIALS AND METHODS

We included qualitative studies, quantitative studies, primary research studies, meta-analyses, and research letters written in English. Full text reviewing was completed in all animal and human studies discussing Li-ESWT for the treatment of ED in subjects with DM. Data extracted included the journal citation, publication year, country of origin, study design, and a summary of the pertinent findings.

RESULTS

Our search yielded nine clinical studies and 10 animal studies. The results of the clinical studies suggest that Li-ESWT is a safe and effective treatment in men with well-controlled DM and moderate or better ED. However, the benefit is less durable in diabetic men than nondiabetic men. The results of the animal studies suggest that Li-ESWT can significantly improve erectile function in diabetic rat models with ED.

CONCLUSIONS

The examined studies present encouraging results for the use of Li-ESWT to treat diabetic men with ED. Future studies, particularly robust randomized controlled trials, are necessary to confirm these findings and provide long-term follow-up.

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.

The Treatment Satisfaction in Patients and Their Partners Treated with Low-Intensity Extracorporeal Shock Wave Therapy and Sildenafil: A Prospective Non-Randomized Controlled Study

BACKGROUND

Phosphodiesterase 5 inhibitors (PDE5Is) and other more invasive options merely provide symptomatic relief rather than a permanent improvement in erectile dysfunction (ED), whereas the long-term improvement in ED via low-intensity extracorporeal shockwave therapy (Li-ESWT) has been confirmed. So far, no comparative study of sildenafil versus Li-ESWT has been conducted with respect to treatment satisfaction.

OBJECTIVE

In this study, we aim to compare erectile function status and satisfaction rates in patients who received sildenafil or Li-ESWT for ED.

METHODS

Patients complaining of ED were considered candidates. Participants chose to enter one of two active treatment groups according to their treatment intention-either a 9-week Li-ESWT regimen or 100 mg on-demand sildenafil. The erectile function was evaluated using the erectile function domain of the International Index of Erectile Function questionnaires (IIEF-EF), while the treatment satisfaction was evaluated using the Erectile Dysfunction Inventory of Treatment Satisfaction questionnaires (EDITS).

RESULTS

We enrolled 72 participants in the study (42 in the Li-ESWT group and 30 in the sildenafil group). Patients in both groups were young men. Four weeks after the last session, the IIEF-EF score for Li-ESWT and sildenafil was 16.3± 5.5 and 18.3± 6.5 (P > 0.05), respectively. The total EDITS index of the patient version and the partner version were similar in the two groups. Among EDITS questions measuring overall satisfaction and efficacy duration, the score was higher in the Li-ESWT group.

CONCLUSION

We found that Li-ESWT may have better satisfaction than on-demand sildenafil for young ED patients. However, further studies are needed to determine the factors influencing satisfaction.

The role of microRNAs in erectile dysfunction: From pathogenesis to therapeutic potential

Erectile dysfunction (ED) is a common male sexual dysfunction disease, and it was predicted that the number of ED patients worldwide will reach 322 million by 2025. However, the pathogenesis of ED is complex and the current treatment options are still limited, so it is urgent to explore new treatment strategies. Recent studies have shown that microRNAs (miRNAs) play an important role in ED, and these single-stranded non-coding small RNA molecules are involved in key pathophysiological processes in the occurrence and development of ED. Therefore, miRNAs have remarkable potential as therapeutic targets in ED. Here, this review introduces the physiological basis of erectile function and the pathophysiological changes in ED and summarizes the current knowledge on the expression, biological functions, and molecular mechanisms of miRNAs in ED, especially the potential of miRNA-targeted therapies to improve ED. This review will provide a comprehensive view of the role of miRNAs in the pathogenesis of ED and the potential value of miRNAs in the treatment of ED.

Male Sexual Dysfunction

Male sexual dysfunction is a series of conditions, most notably including erectile dysfunction (ED), Peyronie's disease (PD), and premature ejaculation (PE), defined by impaired sexual functioning. The prevalence of male sexual dysfunction increases with age and is relatively high with greater than 50% of men aged 40 to 70 describing some degree of erectile dysfunction. Risk factors for male sexual dysfunction include age, diabetes mellitus (DM), cancer, stroke, hypertension, penile trauma, depression, anxiety, and disturbance in central serotonin neurotransmission and 5-HT postsynaptic receptor functioning. Sexual questionnaires including the International Index of Erectile Dysfunction, Sexual Health Inventory for Men, and the Premature Ejaculation Diagnostic Tool are useful in screening for these disorders. Focused history and physical can establish diagnoses. For a condition to be diagnosed as male sexual dysfunction, the patient or their partner must view their sexual functioning as impaired. Treatment of male sexual dysfunction is etiology dependent. For ED, first-line therapy is a phosphodiesterase-5 inhibitor or mental health care for psychogenic ED. More complicated cases may be treated with injections, surgery, or shockwave therapy. PD is either treated with medications for pain management, collagenase clostridium histolyticum injection, corpoplasty, plication, or shockwave therapy. PE may be treated behaviorally or with SSRIs as first line medication.

Impact of extracorporeal shockwave therapy for erectile dysfunction and peyronie's disease on reproductive and hormonal testicular function

Introduction

Extracorporeal shock wave therapy is an established treatment for erectile dysfunction and Peyronie's disease. Concerns regarding the safety of extracorporeal shock wave therapy for andrological purposes on testicular function were raised by animal studies.

Aim

To evaluate the impact of extracorporeal shock wave therapy for erectile dysfunction or Peyronie's disease on reproductive and hormonal testicular function.

Methods

We designed a prospective controlled study in which consecutive patients were enrolled. Males aged between 18 and 40 years with mild vasculogenic erectile dysfunction or acute inflammatory Peyronie's disease and normozoospermia were included. All enrolled patients were offered extracorporeal shock wave therapy, and subjects who refused extracorporeal shock wave therapy for any reason were considered as the Control group. All patients in the Intervention group were treated with DUOLITH SD1 T‐TOP by a single expert urologist. Semen analysis and serum total testosterone dosage were performed before the start (T0) and 3 months after the end of extracorporeal shock wave therapy (T1) in Intervention group. The same parameters were evaluated after the extracorporeal shock wave therapy refusal (T0) and at the end of the following 3 months (T1) in Control group. Normozoospermia was chosen as the primary outcome, serum total testosterone concentration was selected as the secondary outcome.

Results

A total of 94 patients were enrolled in the study (48 Group A, 46 Group B). At T0, all patients were normozoospermic in both groups (p = 0.563), and no significant difference in mean ± SD total testosterone levels was recorded between the groups (582.5 ± 107.2 vs. 634.6 ± 108.4 ng/dl; p = 0.221). At T1, no significant deterioration (p > 0.05) in semen parameters was recorded in both groups. Only a statistically significant reduction in seminal pH was found after extracorporeal shock wave therapy compared to baseline (7.9 ± 0.3 vs. 7.5 ± 0.2; p < 0.001) and untreated patients (7.8 ± 0.2 vs. 7.5 ± 0.2; p < 0.001). No significant difference in total testosterone levels was recorded in Intervention group after extracorporeal shock wave therapy compared to baseline (p = 0.584).

Conclusion

Extracorporeal shock wave therapy in erectile dysfunction and Peyronie's disease patients does not seem to affect reproductive and hormonal testicular function.

Microenergy acoustic pulse therapy restores urethral wall integrity and continence in a rat model of female stress incontinence

OBJECTIVE

To determine the outcomes and mechanisms of microenergy acoustic pulse (MAP) therapy in an irreversible rat model of female stress urinary incontinence.

MATERIALS AND METHODS

Twenty-four female Sprague-Dawley rats were randomly assigned into four groups: sham control (sham), vaginal balloon dilation and ovariectomy (VBDO), VBDO + β-aminopropionitrile (BAPN), and VBDO + β-aminopropionitrile treated with MAP (MAP). MAP therapy was administered twice per week for 4 weeks. After a 1-week washout period, all 24 rats were evaluated with functional and histological studies. The urethral vascular plexus was examined by immunofluorescence staining with antibodies against collagen IV and von Willebrand factor (vWF). The urethral smooth muscle stem/progenitor cells (uSMPCs) were isolated and functionally studied in vivo and in vitro.

RESULTS

Functional study with leak point pressure (LPP) measurement showed that the MAP group had significantly higher LPPs compared to VBDO and BAPN groups. MAP ameliorated the decline in urethral wall thickness and increased the amount of extracellular matrix within the urethral wall, especially in the urethral and vaginal elastic fibers. MAP also improved the disruption of the urethral vascular plexus in the treated animals. In addition, MAP enhanced the regeneration of urethral and vaginal smooth muscle, and uSMPCs could be induced by MAP to differentiate into smooth muscle and neuron-like cells in vitro.

CONCLUSION

MAP appears to restore urethral wall integrity by increasing muscle content in the urethra and the vagina and by improving the urethral vascular plexus and the extracellular matrix.

Analysis of the Impact of Clinical Factors on Low-Intensity Extracorporeal Shockwave Therapy for Erectile Dysfunction

INTRODUCTION

Predictive factors for the treatment success of low-intensity extracorporeal shockwave therapy (Li-ESWT) for erectile dysfunction (ED) are still under debate.

METHODS

Li-ESWT was performed in 50 patients suffering from ED by applying 3,000 shock waves once a week over a period of 6 weeks. Treatment success was defined as an increase in the International Index of Erectile Function 5 (IIEF-5) score by ≥5 points or an Erectile Hardness Score (EHS) of ≥3 points. IIEF-5 and EHS were measured at baseline and at 3 and 6 months of follow-up.

RESULTS

Treatment success according to either the IIEF-5 score or EHS at any time of follow-up was achieved in 28 patients (56%). Twenty-five patients (50%) experienced an improvement during the first 3 months, which lasted for 6 months in 8 cases (16%). Three patients reported improved erectile function only after 6 months. When stratifying the cohort with regard to potential influencing factors, a significantly improved IIEF-5 score could be achieved in men with cardiovascular risk factors (p = 0.026) and in men with antihypertensive medication (p = 0.009). Men without cardiovascular risk factors showed no therapeutic benefit from Li-ESWT.

DISCUSSION/CONCLUSION

Li-ESWT is a valid but often short-lived treatment option for ED, especially in men with cardiovascular risk factors or controlled hypertension. Future studies should assess the feasibility and safety of repeated applications of Li-ESWT.

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.

The Effect of Combination Treatment with Low-Intensity Shockwave Therapy and Tadalafil on Mild and Mild-To-Moderate Erectile Dysfunction: A Double-Blind, Randomized, Placebo-Controlled Clinical Trial

BACKGROUND

Combination of different first-line treatments for erectile dysfunction (ED) has emerged as a promising therapeutic approach.

AIM

To conduct the first double-blind, randomized, placebo-controlled clinical trial to evaluate the efficacy and safety of combination therapy with low-intensity shockwave therapy (LiST) and tadalafil vs LiST and placebo in patients with mild or mild-to-moderate vasculogenic ED.

METHODS

Fifty sexually active patients fulfilling the eligibility criteria were randomly assigned to 6 sessions of LiST twice weekly for 3 weeks and tadalafil (n = 25) or placebo (n = 25) once daily for 4 weeks. Patients were evaluated at 1, 3, and 6 months after completion of the treatment protocol.

OUTCOMES

The primary outcome was the mean change from baseline in the International Index of Erectile Function-Erectile Function (IIEF-EF) domain between the 2 groups at 3 months after treatment. Erectile function was also assessed at 1 and 6 months. The number of patients attaining a minimal clinically important difference (MCID) in the IIEF-EF, as well as the safety of combination therapy were evaluated.

RESULTS

Adjusting for the baseline values, IIEF-EF improved by 0.8 points more (95% confidence interval [CI] = -0.2 to 1.9, P = .12) at 1 month, 1 point more (95% CI = 0.1-1.9, P = .02) at 3 months and 1.7 points more (95% CI = 0.8-2.7, P < .001) at 6 months in patients treated with combination therapy compared to monotherapy. The number of patients attaining a MCID in the IIEF-EF between the 2 groups improved significantly only at the 3-month evaluation. No adverse events were reported during the whole study period.

CLINICAL IMPLICATIONS

Combination of LiST twice weekly for 3 weeks and tadalafil 5 mg once daily for 4 weeks may further ameliorate mild or mild-to-moderate vasculogenic ED compared to LiST monotherapy.

STRENGTHS & LIMITATIONS

We conducted the first randomized trial exploring the role of LiST and tadalafil in the management of ED. Conversely, our study lacks external validity due to its single-center design.

CONCLUSION

The addition of daily low-dose tadalafil during application of LiST may further improve erectile function compared to application of LiST as a standalone treatment in patients with mild or mild-to-moderate vasculogenic ED. Still, further high-quality studies are warranted to corroborate our findings.

A single-centre result of two courses of low-intensity shockwave therapy (Li-SWT) in erectile dysfunction

The purpose of this study is to evaluate the results of two courses of low-intensity shock wave therapy (Li-SWT) in the treatment of patients with erectile dysfunction (ED). Between June 2015 and December 2020, diabetic and non-diabetic patients with ED treated with two Li-SWT courses were evaluated retrospectively among the data of 317 patients. The outcomes were evaluated using the International Index of Erectile Function-Erectile Function Domain (IIEF-EF) questionnaire values at baseline and 6 months post-treatment for each Li-SWT course with (0.09 mJ/mm²) 18000 shock waves. Successful treatment criteria for patients who also underwent physical examination and anamnesis before and after each course were IIEF-EF scores≥26 during the 6 months follow-up. Forty-one patients with a mean age of 51.61 ± 11.80 years were included in the study. The mean IIEF-EF scores were 15.17 ± 3.75 at baseline, 21.61 ± 3.60 after the first course [mean difference(MD): -6.439; 95%, confidence interval(CI), -7.138: -5.740; t = -18.621; p < 0.001], and 25.27 ± 4.05 after the second course(MD: -3.658; 95% CI, -4,067: -3.249; t = -18,071; p < 0.001). Evaluation of score increases in diabetic patients was also statistically significant for each course (p < 0.001). Our study shows that two courses of Li-SWT treatments are safe for both diabetic and non-diabetic patients with ED and effective for each course.

Restorative Therapies for Erectile Dysfunction: Position Statement From the Sexual Medicine Society of North America (SMSNA)

INTRODUCTION

Current non-invasive treatments for erectile dysfunction (ED) include oral medications, intracavernosal injections, and vacuum-assisted devices. Though these therapies work well for many, a subset of patients have contraindications or are unsatisfied with these options. Restorative therapies for ED are a new frontier of treatments focused on regenerating diseased tissue and providing a potential "cure" for ED.

AIM

The aim of this position statement is to examine existing clinical trial data for restorative therapies and identify elements that require further research before widespread adoption.

METHODS

A literature review was performed to identify all clinical trials performed with regenerative therapy for ED. This includes treatments such as stem cell therapy (SCT), platelet rich plasma (PRP), and restorative related technologies like low-intensity shockwave therapy (LiSWT).

MAIN OUTCOME MEASURES

Most clinical trials in restorative therapies were assessed for safety, feasibility, or efficacy. This included recording adverse events, changes in sexual function and erectile function questionnaires, and diagnostics measures.

RESULTS

To date there is an absence of robust clinical data supporting the efficacy of restorative therapies regarding ED, though technologies such as LiSWT have established relative safety.

CONCLUSIONS

Restorative therapies are a promising technology that represents a new frontier of treatment geared towards reversing disease pathology rather than just treating symptoms. However, current published clinical studies are limited. Future work needs to be adequately powered, multi-center, randomized, sham/placebo-controlled trials in well-characterized patient populations to ensure safety and demonstrate efficacy. Until these studies are done, restorative therapies should be reserved for clinical trials and not offered in routine clinical practice. Liu JL, Chu KY, Gabrielson AT, et al. Restorative Therapies for Erectile Dysfunction: Position Statement From the Sexual Medicine Society of North America (SMSNA). J Sex Med 2021;9:100343.

The Effect of Low-intensity Shockwave Therapy on Non-neurogenic Lower Urinary Tract Symptoms: A Systematic Review and Meta-analysis of Preclinical and Clinical Studies

CONTEXT

Low-intensity shockwave therapy (LiST) has emerged as an effective treatment for pain in patients with chronic prostatitis/chronic pelvic pain syndrome (CP/CPPS), and it has been postulated that LiST may also be effective in patients with lower urinary tract symptoms (LUTS).

OBJECTIVE

To perform a systematic review and meta-analysis of experimental and clinical studies exploring the effect of LiST on LUTS in an attempt to provide clinical implications for future research.

EVIDENCE ACQUISITION

We systematically searched PubMed, Cochrane Library, and Scopus databases from inception to March 2021 for relevant studies. We provided a qualitative synthesis regarding the role of LiST in LUTS and performed a single-arm, random-effect meta-analysis to assess the absolute effect of LiST on LUTS only in patients with CP/CPPS (PROSPERO: CRD42021238281).

EVIDENCE SYNTHESIS

We included 23 studies (11 experimental studies, seven nonrandomized controlled trials [non-RCTs], and five RCTs) in the systematic review and seven in the meta-analysis. All experimental studies were performed on rats with LUTS, and the clinical studies recruited a total of 539 participants. In patients with CP/CPPS, the absolute effect of LiST on maximum flow rate and postvoid residual was clinically insignificant. However, the available studies suggest that LiST is effective for the management of pain in patients with either CP/CPPS or interstitial cystitis/bladder pain syndrome. Additionally, LiST after intravesical instillation of botulinum neurotoxin type A may enhance its absorption and substitute botulinum neurotoxin type A injections in patients with overactive bladder. Furthermore, the available evidence is inconclusive about the role of LiST in patients with benign prostatic obstruction, stress urinary incontinence, or underactive bladder/detrusor hypoactivity.

CONCLUSIONS

LiST may be effective for some disorders causing LUTS. Still, further studies on the matter are necessary, since the available evidence is scarce.

PATIENT SUMMARY

Low-intensity shockwave therapy represents a safe, easily applied, indolent, and repeatable on an outpatient basis treatment modality that may improve lower urinary tract symptoms.

[Low-intensity extracorporeal shock wave therapy for erectile dysfunction: A systematic review]

INTRODUCTION

Our purpose was to assess the efficacy of low intensity extracorporeal shock waves (SW) for the treatment of organic erectile dysfunction (ED).

METHODS

A systematic review of the literature published between 2000 and 2020 was conducted using the PRISMA methodology. We used Medline data with the following key words (MesH): "extracorporeal shock wave therapy"; "erectile dysfunction"; "sexuality".

RESULTS

Nineteen articles were selected: thirteen randomised controlled trial and six meta-analyses. Most of them studied vascular etiology. Low intensity SW is beneficial ED is evaluated by the IIEF, EHS scores and penile hemodynamic.

CONCLUSION

SW may have a theoretical impact on the vascular etiology of organic DE. Their use in this context is supported by the European Society of urology and the European Society of sexual medecine. However, there are discrepancies in current data to establish a protocol to follow in daily practice.

The Effect of Low-Intensity Extracorporeal Shockwave Treatment on the Urinary Bladder in an Experimental Diabetic Rat Model

Purpose

Preclinical data increasingly support an impact of low-intensity extracorporeal shockwave therapy (Li-ESWT) on the bladder. We investigated the molecular effects of Li-ESWT on the bladder of a streptozotocin-induced diabetic rat model.

Methods

Fifteen 8-week-old male Wistar rats were randomized into 3 groups: a control group (n=5), a group of diabetic rats without treatment (diabetes mellitus [DM], n=5) and a group of diabetic rats treated with Li-ESWT (DM-ESWT, n=5). A single intraperitoneal dose of streptozotocin (60 mg/kg) was used to induce diabetes. Twenty days after diabetes induction, each rat in the DM-ESWT group received 300 shockwaves with an energy flux density of 0.09 mJ/mm². Sessions were repeated 3 times/week for 2 weeks, followed by a 2-week washout period. Total RNA from bladder tissue was extracted, cDNA was synthesized, and quantitative real-time polymerase chain reaction was performed to analyze the expression pattern of transient receptor potential vanilloid 1 (Trpv1), interleukin-1β (Il1b), and the muscarinic receptors M1, M2, and M3 (Chrm1, Chrm2, and Chrm3).

Results

The expression of Trpv1, Il1b, and Chrm2 genes was significantly different between the 3 groups (P=0.002, P<0.0001, and P=0.011, respectively; 1-way analysis of variance). In the DM group, the expression of all genes was higher than in the control group, but statistical significance was observed only for Trpv1 and Il1b (P=0.002 and P<0.0001, respectively). Li-ESWT significantly reduced the expression of Il1b and Chrm2 (P=0.001 and P=0.011, respectively), whereas a nonsignificant tendency for reduced expression was noted for Trpv1 (P=0.069).

Conclusions

The induction of diabetes was associated with increased expression of genes related to mechanosensation, inflammation/ischemia, and contraction in the rat bladder. Li-ESWT reduced the expression of IL1b, Chrm2, and to a lesser extent Trpv1 toward the control levels, suggesting the therapeutic potential of this treatment modality for diabetic cystopathy.

Li-Eswt improves hemodynamic parameters thus suggesting neoangiogenesis in patients with vascular erectile dysfunction

Extracorporeal treatment with low intensity shock-wave therapy (LI-ESWT) is a recently introduced non-invasive method which purposes the restoration of the pathophysiological alterations at the base of vasculogenic ED in male patients. The evidence in favour of the neoangiogenic potential of this treatment derived from in vitro studies and on animal models. The purpose of this study, in which the Power Doppler method was applied, is to demonstrate 'objectively' the real efficacy of LI-ESWT at the level of the microcirculation of the corpora cavernosa (neoangiogenesis) in patients affected by vasculogenic ED. Data from this study show, for the first time, that LI-ESWT treatment promotes neovascularisation of the functional arteries in patients affected by vasculogenic ED.

Effect of low-intensity extracorporeal shock wave therapy on diabetic erectile dysfunction: Randomised control trial

This study aimed to assess the effectiveness of low-intensity extracorporeal shockwave therapy (Li-ESWT) in the management of erectile dysfunction in diabetic patients with mixed vasculogenic and neurogenic causes as confirmed by nerve conduction and Doppler studies. This randomised controlled trial included 42 patients 41-55 years of age with a confirmed diagnosis of erectile dysfunction and diabetic polyneuropathy. They were randomly allocated to one of two groups: shock wave group (n = 21) treated with Li-ESWT plus pelvic floor muscle training and control Group (n = 21) treated with pelvic floor muscle exercise and sham therapy by a shock wave. The erectile function was scored according to the five-item version of the International Index of Erectile Function (IIEF-5). Colour-coded duplex sonography was used for the evaluation of penile perfusion of the two cavernous arteries. The assessment was done before and three months after treatment. IIEF-EF increased significantly in the study group (p < .001), but not in the control group (p = .194). Peak systolic velocity increased significantly in the two groups; however, the post-treatment peak systolic velocity was significantly higher in the study group compared to the control group (p < .001, for both arteries).

Comparison of the efficacy and safety of low-intensity extracorporeal shock wave therapy versus on-demand sildenafil for erectile dysfunction

Background

Low-intensity extracorporeal shock wave therapy (Li-ESWT) is an effective therapy for erectile dysfunction (ED) but is not widely recognized and applied. This prospective nonrandomized study aimed to investigate the efficacy and safety of Li-ESWT.

Methods

After a 4-week washout period of past ED treatment, patients entered one of 2 active treatment groups, either 9-week Li-ESWT or 100 mg on-demand sildenafil. Patients were evaluated in the first- and third-month following initiation of treatment. The Li-ESWT protocol comprised 2 sessions per week for 3 weeks, which were repeated after a 3-week interval. Patients in the drug group took self-administered sildenafil at a dose of 100 mg before intercourse. The primary outcome was the effectiveness of Li-ESWT measured by the International Index of Erectile Function-5 (IIEF-5) scores. Other measurements included erection hardness score (EHS) and Self-Esteem And Relationship (SEAR).

Results

A total of 78 participants completed the study (46 in the Li-ESWT group and 32 in the sildenafil group). Overall, 26.9% of the participants (21/78) included were psychogenic. In the third month, the outcome measured by IIEF-5 was 21.52 in the Li-ESWT group and 21.26 in the sildenafil group (P>0.05). Proportion of improvement defined by minimal clinically important difference (MCID) criteria was 52.2% in the Li-ESWT group and 59.4% in the sildenafil group (P>0.05). The EHS and SEAR improvement was similar in the 2 groups (P>0.05 at baseline and third month). Transient and mild adverse events were observed in both groups.

Conclusions

In our study, a similar treatment efficacy and safety was shown by the application of Li-ESWT as on demand sildenafil.

Focused Extracorporeal Shockwave Therapy in Physical Medicine and Rehabilitation

Purpose of Review

Focused extracorporeal shockwave therapy (fESWT) is a physical treatment modality developed over the last 25 years for musculoskeletal indications. It has many indications in the field of physical medicine and rehabilitation (PM&R) and is effective, time-efficient, and cost-efficient. This review focuses on basics and on clinical indications as well as on significant trends in fESWT.

Recent Findings

In PM&R, stimulation of healing processes in tendons, surrounding tissue, and bones via mechanotransduction seems to be a relevant biological effect. The International Society for Medical Shockwave Treatment (ISMST) describes different types of indications (such as approved standard indications—in accordance with most scientific evidence—like calcifying tendinopathy of the shoulder, plantar fasciitis lateral epicondylopathy of the elbow, greater trochanter pain syndrome, patellar tendinopathy, Achilles tendinopathy and bone non-union, common empirically tested clinical uses, exceptional or expert indications, and experimental indications).

Summary

fESWT is a relevant treatment option in PM&R and regenerative medicine. In recent years, historical paradigms (for example, application in cancer patients) have changed and new indications (such as nerve regeneration, myofascial trapezius syndrome, low back pain, dermatosclerosis, and lymphedema) are supported. Future translational research should focus on establishing actual exceptional indications and experimental indications for clinical routine.

Retrospective comparison of focused shockwave therapy and radial wave therapy for men with erectile dysfunction

Background

Low-intensity shockwave therapy (SWT) is an emerging treatment for erectile dysfunction (ED). Devices used for SWT include focused shockwave therapy (fSWT) or radial wave therapy (rWT), which differ in how the waves are generated, their tissue penetration, and the shape of their pressure waves. Most studies of SWT for ED to date have utilized fSWT. Although widely used, the efficacy of rWT for ED is unknown. Our objective is to compare the efficacy of rWT and fSWT for ED at our institution.

Methods

A retrospective chart review was performed to identify all men with ED treated by fSWT or rWT. Men with history suggesting non-vasculogenic ED were excluded. All men received 6 consecutive weekly treatments. The fSWT group received 3,000 shocks per treatment at 0.09 mJ/mm². The rWT group received 10,000 shocks per treatment at 90 mJ and 15 Hz. Pre-treatment and 6-week post-treatment Sexual Health Inventory in Men (SHIM) scores were measured. Treatment response was categorized on a scale of 1–3 (1 if no improvement, 2 if erections sufficient for intercourse with phosphodiesterase 5 inhibitors (PDE5i), or 3 if sufficient erections without PDE5i). Primary endpoint was self-reported improvement score of 2 or greater.

Results

A total of 48 men were included: 24 treated by fSWT and 24 by rWT. There were no significant differences in age, duration of ED, pre-treatment PDE5i use, or pre-treatment SHIM scores between the groups. Following treatment with rWT, the mean SHIM score improved from 9.3 to 16.1 (P<0.001). The mean SHIM following fSWT improved from 9.3 to 15.5 (P<0.001). The mean improvement in SHIM score did not differ between rWT (6.8) and fSWT (6.2) (P=0.42). 54% of men treated by fSWT experienced a significant clinical improvement (≥ grade 2 response) compared to 75% in the rWT group (P=0.42). There were no reported side effects with either device.

Conclusions

In our patient population, both fSWT and rWT were moderately effective treatments for arteriogenic ED with no observable difference in efficacy between the two modalities.

Low intensity shockwave therapy in combination with phosphodiesterase-5 inhibitors is an effective and safe treatment option in patients with vasculogenic ED who are PDE5i non-responders: a multicenter single-arm clinical trial

Low-intensity shockwave therapy (Li-ESWT) has been shown to be an effective and safe treatment for vasculogenic erectile dysfunction (ED). We aim to evaluate the effectiveness and safety of LiESWT in treating patients affected from vasculogenic ED who did not respond to oral treatment with Phosphodiesterase 5 inhibitors (PDE5-i). It is a multicentric open-label prospective study, in a cohort of patients non-responders to PDE-5i. Li-ESWT was performed in an outpatient setting by using the following schedule: 3000 shockwaves with an energy of 0.25 mJ/mm² and a frequency of 4-6 Hz, twice a week for 3 weeks. International Index of Erectile Function, Erection Hardness Score and Sexual Quality of Life-Male questionnaires, and penile doppler ultrasound (PDU) are the outcome measurements. The Student t-test or Wilcoxon signed-rank test were applied to compare variables, with results considered statistically significant at p < 0.05. 106 (97.2%) completed treatment and performed follow-up visit after 4 weeks. At follow up visit, the mean IIEF-EF increased by 8.6 points (13.47 ± 4.61 vs 22.07 ± 5.27; p < 0.0001). A clinically significant improvement of IIEF-EF was achieved in 75 patients (70.7%). An EHS score ≥ 3, sufficient for a full intercourse, was reported by 72 patients (67.9%) at follow-up visit. 37 (34.9%) patients reported a full rigid penis (EHS = 4) after treatment. Li-ESWT treatment was also able to improve quality of life (SQOL-M: 45.56 ± 8.00 vs 55.31 ± 9.56; p < 0.0001). Li-ESWT significantly increased mean PSV (27.79 ± 5.50 vs 41.66 ± 8.59; p < 0.0001) and decreased mean EDV (5.66 ± 2.03 vs 1.93 ± 2.11; p < 0.0001) in PDU. Combination of Li-ESWT and PDE5-i represents an effective and safe treatment for patients affected from ED who do not respond to first line oral therapy.

Clinical Practice Guideline Recommendation on the Use of Low Intensity Extracorporeal Shock Wave Therapy and Low Intensity Pulsed Ultrasound Shock Wave Therapy to Treat Erectile Dysfunction: The Asia-Pacific Society for Sexual Medicine Position Statement

Published literature shows low intensity extracorporeal shock wave therapy (LIESWT) and low intensity pulsed ultrasound (LIPUS) therapy to improve erectile function and penile hemodynamic by inducing neovascularisation and promoting tissue regeneration. Key opinion leaders across the Asia Pacific region attended the recent biennial meeting of the Asia Pacific Society for Sexual Medicine in Australia, and presented the current evidence on LIESWT and LIPUS for erectile dysfunction (ED). The clinical findings were internally discussed, and the quality of evidence was graded based on the Oxford Centre for Evidence-Based Medicine recommendations. Existing literature supports the use of LIESWT and LIPUS in men with ED, with many clinical studies reported encouraging results with improved erectile function, good safety profile and short-term durability. However, controversial exists due to sampling heterogeneity, non-standardised treatment protocol and lack of large multiinstitutional studies. There is a need to better define which subgroup of ED population is best-suited, and specific treatment protocol to optimise shock wave energy delivery. More stringent and larger multi-institutional randomised placebo-controlled trials are warranted before clinical adoption of LIESWT and LIPUS as the new standard of care for men with ED.

The Basic Physics of Waves, Soundwaves, and Shockwaves for Erectile Dysfunction

INTRODUCTION

Over the past decade, low-intensity extracorporeal shockwave therapy (Li-ESWT) has emerged as a treatment modality for erectile dysfunction (ED). To better appreciate the differences between the various devices for the treatment of ED, it is imperative for physicians to understand the underlying physics of the different shockwave generators.

AIM

In this article, we explain the physics of shockwaves by establishing a foundation regarding the basics of waves, specifically soundwaves. We also describe the different shockwave generators available and assess their potential clinical utility.

METHODS

We reviewed basic principles of wave propagation, randomized controlled trials investigating Li-ESWT for ED and other medical diseases, and individual industry shockwave generator websites, in order to describe the basic physics underlying Li-ESWT.

MAIN OUTCOME MEASURE

We primarily aimed to describe the physics underlying shockwave generators and to provide a framework for understanding the relevant subtypes and adjustable parameters.

RESULTS

A wave is a disturbance in a medium that transports energy without permanently transporting matter. In shockwaves, a soundwave is generated with a speed faster than the local speed of sound. Shockwaves are classically generated by three different types of energy sources: electrohydraulic, electromagnetic, or piezoelectric, which all create a shockwave through the conversion of electric potential energy to mechanical energy. Importantly, radial pressure waves do not behave the same as conventional shockwaves and are more like "ordinary" sound waves in that they achieve a significantly lower peak pressure, a slower rise time, and propagate outwards without a focal point.

CLINICAL IMPLICATIONS

Li-ESWT is not currently approved by the U.S. Food and Drug Administration and is considered investigational in the United States. However, it is currently available to patients under clinical trial protocols and it is important to understand the basic physics of shockwaves to understand the differences between the different shockwave devices.

STRENGTH & LIMITATIONS

This is a comprehensive review of the physics underlying Li-ESWT but only tangentially explores the biological impact of shockwaves.

CONCLUSION

Physicians currently using or those contemplating purchasing a Li-ESWT device should understand the basic physics underlying the device, as well as which treatment protocols were used to demonstrate clinical efficacy in treating ED. Katz JE, Clavijo RI, Rizk P, et al. The Basic Physics of Waves, Soundwaves, and Shockwaves for Erectile Dysfunction. Sex Med Rev 2020;8:100-105.

Extracorporeal Shock Waves Therapy Delivered by Aries Improves Erectile Dysfunction in Spontaneously Hypertensive Rats Through Penile Tissue Remodeling and Neovascularization

Background

Low-intensity extracorporeal shock wave therapy (Li-ESWT) has been reported to improve erectile function in patients with moderate-to-severe erectile dysfunction (ED) or even convert phosphodiesterase type 5 inhibitors nonresponders to responders. ED is highly prevalent in hypertensive patients. The effect of Li-ESWT on an animal model of hypertension-associated ED has not been reported.

Aim

To investigate the effect of Li-ESWT on hypertension-associated ED and provide plausible mechanisms of action of Li-ESWT on local mechanisms of penile erection.

Methods

Spontaneously hypertensive rats (SHRs) in the active group (n = 13) received Li-ESWT at energy flux density 0.06 mJ/mm² (Aries; Dornier MedTech, Wessling, Germany) twice weekly for 6 weeks. The emitter was set to zero for SHRs in the sham group (n = 12). Erectile function was assessed 4 weeks post-treatment by monitoring intracavernosal pressure (ICP) in response to electrical stimulation of cavernous nerve before and after single dose of 0.3 mg/kg intravenous sildenafil. Cavernosal tissue was then evaluated for collagen/smooth muscle content, neuronal nitric oxide synthase (nNOS), and vascular endothelial factor (CD31) expression.

Outcomes

Erectile function was assessed with ICP, erectile tissue remodeling was studied by smooth muscle/collagen ratio, nNOS and CD31 were semiquantitatively evaluated on cavernosal sections.

Results

The improvement of ICP parameters was greater in Li-ESWT–treated rats compared with controls with and without sildenafil. Sildenafil led to 20% increase in area under the intracavernosal pressure curve measured during the entire response/mean arterial pressure at 10 Hz in ESWT_SHR + sildenafil compared with ESWT_SHR. The smooth muscle/collagen ratio increased 2.5-fold in Li-ESWT compared with sham. Expression of CD31 tended to be increased whereas nNOS was unchanged.

Conclusions

Li-ESWT by Aries may represent an effective noninvasive therapeutic alternative and a relevant add-on therapy to phosphodiesterase type 5 inhibitors for ED in hypertensive patients, and it is suggested that it acts via remodeling of the penile tissue and promoting cavernosal vascularization.

Assaly R, Giuliano F, Clement P, et al. Extracorporeal Shock Waves Therapy Delivered by Aries Improves Erectile Dysfunction in Spontaneously Hypertensive Rats Through Penile Tissue Remodeling and Neovascularization. Sex Med 2019;7:441–450

Low-intensity shockwave therapy (LiST) for erectile dysfunction: a randomized clinical trial assessing the impact of energy flux density (EFD) and frequency of sessions

The impact of energy flux density (EFD) used on low-intensity shockwave therapy (LiST) for erectile dysfunction (ED) has not been explored. Our aim was to compare EFD 0.05 versus 0.10 mJ/mm² regarding efficacy and safety of 12-treatment sessions when applied two or three times per week. Ninety-seven patients with vasculogenic ED, PDE5 inhibitors users were randomized into four groups, to receive 12 LiST sessions. Group A (n = 24) : two sessions per week, EFD 0.05 mJ/mm²; Group B (n = 24): three sessions per week, EFD 0.05 mJ/mm²; Group C (n = 24): two sessions per week, EFD 0.10 mJ/mm²; Group D (n = 25): three sessions per week, EFD 0.10 mJ/mm². International Index for Erectile Function-Erectile Function domain (IIEF-EF), Minimally clinical important differences (MCID), sexual encounter profile, and triplex ultrasonography parameters were used to asses erectile function. Eighty-nine patients completed the 6-month follow-up (FU). All four groups improved in mean IIEF-EF score, average SEP3 "Yes" response rates at 6-month FU visit compared with baseline (p < 0.001). MCID at 6-month FU visit was achieved in 82.6%, 77.3%, 87%, and 81% in Groups A, B, C, and D, respectively. Mean PSV (cm/s) at baseline versus 3-month FU visit were 30.32 versus 34.67 for Group A, 30.02 versus 35.02 for Group B, 30.2 versus 36.02, for Group C, 29.43 versus 34.3 for Group D (p < 0.01). There were no statistical significant differences in the change of all outcome measures assessing erectile function between different sessions frequency. A tendency for better efficacy using EFD 0.10 mJ/mm² was noticed, although it did not reach statistical significance. No treatment-related side-effects were reported. This study lacks a sham-controlled arm. However, all patients were randomized to the four groups, and baseline characteristics were similar between the groups. Moreover, arterial insufficiency was confirmed among all patients by penile triplex ultrasonography. Conclusively, patients may benefit equally when sessions are applied either two or three per week. An EFD of 0.10 mJ/mm² could result in better outcomes, but further studies are needed to validate this observation.