20% of all men have erectile dysfunction (ED) with men of increasing age being disproportionally affected. The incidence of ED can be as high as 60% in men with Diabetes or cardiovascular disease. Although previously considered a quality of life issue, the presence of erectile dysfunction in an otherwise healthy man is now considered a harbinger of cardiovascular disease. Vascular factors are the leading cause of ED. A multitude of treatment options exists for those men with minimal or moderate erectile dysfunction, including pills, injections, and external devices. Unfortunately, these don’t work for every man and may interact with medications or underlying diseases. Also, they treat the symptoms and not the underlying cause of ED. Besides, most man would like not to have to take drugs to function sexually.
What is LI-SWT?
Low intensity extracorporeal (i.e., outside the body) shockwave therapy (LI-SWT) is a treatment that has been in use since 2010. Patients are usually treated in the office setting once or twice a week for 4 to 6 weeks. The device applies a low-intensity shockwave to the surface of the penis using an ultrasound gel as the coupling agent. LI-SWT appears to have minimal side effects and is well-tolerated without any anesthesia. However, it has not received FDA approval for treatment of erectile dysfunction as of the date of this writing. It has been approved for the treatment of plantar fasciitis. Most of the current research has been directed towards erectile dysfunction. A few studies have evaluated the use of LI-SWT in Peyronie’s disease. This article will address the use of LI-SWT in the treatment of erectile dysfunction.
How Does LI-SWT Work?
It is not definitively known how LI-SWT works. However, the current theory is that the shockwave produced by the device causes stress on cell-membranes and release of growth factors and recruitment of stem cells that promote the development of new penile arteries and reducing inflammatory and cellular stress. In animal studies, there is also evidence to suggest nerve regeneration (Fode et al., Nat. Rev. Urolo. 14:593, 2017). LI-SWT is unique in that it could provide a treatment option that corrects the underlying problem instead of just treating the symptoms of erectile dysfunction.
Literature Reviews of LI-SWT?
Several reviews of studies evaluating the use of LI-SWT have been published this year. The first was an analysis of ten randomized controlled studies completed over the past two years by Sokolakis and Hatzichristodoulou (Int Jour Impot Res, 31:177-194, 2019) has concluded that LI-SWT significantly improved erectile function in patients with vascular ED. All ten studies used a validated questionnaire as the assessment tool and included men with moderate to severe ED. Their analysis also contained only 873 studies followed for less than one year. Three studies also measured penile hemodynamics.
A second systematic review by Brunckhorst et al. (Int Urol Neph, 51:773-781, 2019) reviewed eleven studies with 799 patients. Nine studies found an improvement in ED at six months after treatment with the improvement remaining above baseline out to 12 months.
A third review included seven randomized controlled studies evaluating the effect of LI-SWT on erectile function (Dong et al., Am J Men’s Health, March-April:1-14, 2019). Evaluating outcomes by validated questionnaires (ie., International Index of Erectile Function – erectile function domain [IIEF-EF] and the Erectile Hardness Score [EHS]) they found improvement in erectile function after treatment with LI-SWT.
Although the results have been encouraging, there are still many questions to be answered. What patients will respond to LI-SWT? Will the patients with worse erectile dysfunction, Diabetes and/or heart disease respond better or worse? Does patient age or use of oral or injectable medications used to treat erectile dysfunction affect the results of LI-SWT? What are the contraindications for the use of LI-SWT? Should we be treating men on blood thinners? How does the frequency and length of treatments affect the results? Is it better to use fewer treatments/week over a longer period of time? How does the intensity and number of shocks affect the outcome? Does the type of device matter (linear vs. focused shockwaves)? Focused shockwaves have shown their effectiveness while the results of linear shockwaves are still conflicting. When do the effects of LI-SWT occur and how long does the improvement last? These, among other questions, will need to be answered
Current literature demonstrates an improvement of erectile dysfunction with LI-SWT. However, large, multicentered, randomized controlled studies which include not only qualitative (e.g. validated questionnaires) but also quantitative data (e.g. spectral ultrasound vascular data) are needed before LI-SWT becomes the standard of care. For additional information, please contact us.