Eswt For Male Erectile Dysfunction
Low-intensity extracorporeal shock wave therapy (LI-ESWT) has recently proposed as a novel treatment modality in men with erectile dysfunction (ED). Although, randomized-controlled studies investigating the effect of this new treatment modality revealed promising results in men with vasculogenic ED, several criticisms have been reported associated to the mentioned studies. In this section, we hereby aimed to evaluate the evidence based preclinical and clinical efficacy of Li-ESWT on erectile function both in experimental models and in men with ED according to the recent literature.
The current non-surgical therapeutic options for the treatment of ED include oral PDE5Is and intracavernous injections with various combinations of vasoactive agents (i.e. alprostadil, papaverine, phentolamine). These treatment options have been widely used with high rates of effectiveness and are relatively safe with minimal adverse events reported. However, the most important issues related to these options is that none of these modalities do not have any therapeutic effect in patients with impaired blood supply to the corpora cavernosa, and none of these modalities are curative because they do not provide restoration of endothelial or neuronal function. As a common result, these treatment options only provide symptomatic relief in select patients, in another word ‘These treatment options do not treat the cause of the disease while they temporarily treat the symptoms of the disease’. Therefore, the challenging goal in ED treatment is to develop a modality, which will directly lead to the remodulation of the cavernosal vasculature as well as the re-establishment of neuronal function of the penis and improve erectile capacity.
According to the recent literature, there is a growing tendancy among researchers in the focus of ED research from symptomatic treatment toward restorative therapies, namely stem cell therapy, shockwave therapy and gene therapy with the goal of providing more durable treatment responses and organic erections without the need for medication. These treatment options have been investigated in animal models as well as in humans with promising results. However, because of various drawbacks and limitations associated to the studies that have performed these techniques (ie. lack of control group, heterogenous device specifications and regimens) they are not currently considered as treatment options for patients except of a clinical trial setting.
Current data from several studies suggest that the aim of ‘long-lasting’and ‘curative therapy’ for ED may be met using LI-ESWT applied to the corpora cavernosa. Recently, LI-ESWT has emerged and quickly gained popularity as a potential treatment for ED, as data from both in vivo and in vitro studies have revealed that these SW can stimulate angiogenesis. In the light of the previously reported data showing the efficacy of Li-ESWT on ischemia-induced myocardial dysfunction, researchers have postulated that LI-ESWT therapy applied to the corpora cavernosa may improve penile blood flow parameters and endothelial function by stimulating angiogenesis in the corpora cavernosa. In fact, the biological mechanism of action of SWs on the corpora cavernosa is not fully understood while it has been hypothesized that the targeted tissue is compressed due to the positive acoustic pressure generated by the shock, leading expansion that occurs over tensile elements of the tissue. This phenomenon has been describned as ‘cavitation’. Additionaly, the physical forces generated by that cavitation effect are highly localized and they cause to a localized stress response on endotheial cell membranes secondary to sheering forces. Studies have shown that, this shear stress causes to release of angiogenic factors, such as production of Nitric Oxide (NO) via the increased activity of endothelial NO synthase (eNOS) and neuronal NOS (nNOS), platelet derived growth factor, and vascular endothelial growth factor (VEGF).
Up to now, four meta-analyses have been reported in the literature, and all revealed that LI-ESWT significantly improved EF, as demonstrated by increases in the validated International Index of Erectile Function Questionaire (IIEF) score. However, most of the clinical trials investigating the efficacy of LI-ESWT are mainly focused on men with vasculogenic ED. Studies related to the efficacy of LI-ESWT on neurogenic ED are mostly performed in pre-clinical experimental studies.
