Low-Intensity Extracorporeal Shock Wave Therapy—A Novel Effective Treatment for Erectile Dysfunction in Severe ED Patients Who Respond Poorly to PDE5 Inhibitor Therapyjsm_2498 1..6 Ilan Gruenwald, MD, Boaz Appel, MD, and Yoram Vardi, MD Neuro-urology Unit, Rambam Healthcare Campus, Haifa, Israel DOI: 10.1111/j.1743-6109.2011.02498.x ABSTRACT Introduction. Low-intensity shock wave therapy (LI-ESWT) has been reported as an effective treatment in men with mild and moderate erectile dysfunction (ED). Aim. The aim of this study is to determine the efficacy of LI-ESWT in severe ED patients who were poor responders to phosphodiesterase type 5 inhibitor (PDE5i) therapy. Methods. This was an open-label single-arm prospective study on ED patients with an erection hardness score (EHS)  2 at baseline. The protocol comprised two treatment sessions per week for 3 weeks, which were repeated after a 3-week no-treatment interval. Patients were followed at 1 month (FU1), and only then an active PDE5i medication was provided for an additional month until final follow-up visit (FU2). At each treatment session, LI-ESWT was applied on the penile shaft and crus at five different anatomical sites (300 shocks, 0.09 mJ/mm 2 intensity at120 shocks/min). Each subject underwent a full baseline assessment of erectile function using validated questionnaires and objective penile hemodynamic testing before and after LI-ESWT. Main Outcome Measures. Outcome measures used are changes in the International Index of Erectile Function- erectile function domain (IIEF-ED) scores, the EHS measurement, and the three parameters of penile hemody- namics and endothelial function. Results. Twenty-nine men (mean age of 61.3) completed the study. Their mean IIEF-ED scores increased from 8.8  1 (baseline) to 12.3  1 at FU1 (P = 0.035). At FU2 (on active PDE5i treatment), their IIEF-ED further increased to 18.8  1(P < 0.0001), and 72.4% (P < 0.0001) reached an EHS of 3 (allowing full sexual intercourse). A significant improvement (P = 0.0001) in penile hemodynamics was detected after treatment and this improvement significantly correlated with increases in the IIEF-ED (P < 0.05). No noteworthy adverse events were reported. Conclusions. Penile LI-ESWT is a new modality that has the potential to treat a subgroup of severe ED patients. These preliminary data need to be reconfirmed by multicenter sham control studies in a larger group of ED patients. Gruenwald I, Appel B, and Vardi Y. Low-intensity extracorporeal shock wave therapy—A novel effective treatment for erectile dysfunction in severe ED patients who respond poorly to PDE5 inhibitor therapy. J Sex Med **;**:**–**. Key Words. Low Intensity Extracorporeal Shock Wave Therapy; Erectile Dysfunction; Penis Introduction E rectile dysfunction (ED) is one of the most common disorders of middle-aged men that profoundly affect their quality of life [1]. Although tremendous advances for treating this disorder have been made in the past decade, most currently available treatment modalities still rely on an “on demand” regime, of which up to 35% are unsuc- cessful [2–4]. From our experience, ED patients who were treated with a phosphodiesterase type 5 inhibitor (PDE5i) tend to search for an alternative treatment modality that would ameliorate their ED. Hence, there is a need for an effective new 1 © 2011 International Society for Sexual Medicine J Sex Med **;**:**–**