Erectile dysfunction (ED) is the inability to attain and/or maintain penile erection sufficient for satisfactory sexual performance. It is a highly prevalent disorder affecting 150 million men worldwide and 30 million in the United States. ED is a harbinger of cardiovascular disease, and its management should include lifestyle counseling and treatment of underlying associated conditions. Lifestyle modifications, such as improved diet and increased physical activity, may improve the patient’s overall health and reverse the underlying pathophysiology causing ED.

There has been increased interest by the medical community and general public in finding treatments to reverse the underlying causes for ED beyond lifestyle modifications. Low intensity shockwave treatment (LiSWT) and platelet-rich plasma (PRP) injections are promising options that have become more common with the rise of men’s health clinics. However, the American Urological Association and Sexual Medicine Society of North America have advised that LiSWT and PRP be considered investigational and experimental treatments, respectively. Both groups have recommended these agents only be pursued under research protocols in compliance with institutional review board approval.

LiSWT

LiSWT has been used to treat ED for more than 10 years. It is postulated that LiSWT produces an acoustic wave that interacts with the target tissue, inducing a cascade of biologic reactions promoting neovascularization.¹ Nevertheless, high quality data investigating the effect of LiSWT is insufficient. Many questions remain due to a lack of consistency among the trials completed to date. The inability to draw conclusions arises from variation in shockwave generators, type of shockwaves used, energy use, number of pulses per session, duration of treatment, sessions per week and penile sites of application.^2–4

Several meta-analyses have shown that LiSWT can increase International Index of Erectile Function (IIEF) score by mean of 2 to 6.4 points. Studies also reported an improvement in Erection Hardness Scores (EHS).^2–4 This appears to be most pronounced in men with mild, vasculogenic ED. Data suggest that it could improve erectile quality or response to erectile aids, downgrading treatment needs to less invasive options. However, it must be noted that there was a significant variability in shockwave generators, treatment protocols and followup duration. The authors recommended that future trials use 18,000 shocks with a followup of at least 3 months with controls receiving sham treatment. Additionally, phosphodiesterase inhibitors must be stopped with an appropriate washout period for all patients. Given there were no significant adverse events, condensed protocols (defined as shorter than 6 weeks) may be considered. Some data suggest that applying a greater number of shocks (at least 3,000) per session and using a lower energy flux density may improve outcomes.

Our group is currently performing a prospective, randomized, single-blind, sham-controlled clinical study aimed at evaluating the safety and efficacy of LiSWT on symptomatic ED patients in 3 distinct patient populations: mild-moderate ED, patients after prostate cancer treatment and patients planning to undergo prostate cancer treatment. We are unlikely to see industry sponsored trials in the future, so investigator initiated trials need to be methodologically sound to answer some of these remaining questions.

PRP

PRP is autologous blood plasma that contains more than 4 times the normal human physiological serum platelet concentration and inherently contains growth factors that may promote tissue healing and neovascularization.⁵ Data on PRP is less mature than LiSWT, although 2 clinical studies on PRP were reported recently. Epifanova et al demonstrated an improvement in penile Doppler parameters (peak systolic flow, resistive index), IIEF and sexual encounter profile score in men receiving PRP.⁵ No adverse events were noted. In an effort to decrease washout, Matz et al used platelet-rich fibrin matrix (PRFM) instead of PRP in 17 patients with ED and/or Peyronie’s disease.⁶ They reported a 4.14 improvement IIEF-5 score and mild penile bruising in 3 patients after undergoing intracavernosal injections. These authors suggest that PRP is safe, but larger studies are needed to assess its efficacy in treating ED.

Conclusion

LiSWT and PRP may be promising treatment options for patients with ED. However, until high quality data are available, they must continue to be used in an experimental setting.