Corpus cavernosum electromyography with revised methodology: an explorative study in patients with erectile dysfunction and men with reported normal erectile function.

INTRODUCTION

A lack of standardization of the recording techniques of corpus cavernosum electromyography (CC-EMG) and objective criteria to characterize the recorded signals (CC-potentials) are the main difficulties hindering the clinical application of this method. These difficulties have been recently overcome by revising the recording and interpretation methodology of CC-EMG AIM: To assess if CC-EMG performed with the revised methodology is discriminative for well-defined clinical conditions in patients with erectile dysfunction (ED).

METHODS

Based on blinded clinical diagnosis, ED patients were catalogued into five subgroups: severe penile fibrosis, cavernous arterial insufficiency (CAI), cardio-vascular comorbidity (CVCM) without proven CAI, post-radical retropubic prostatectomy (RRP), and psychogenic ED. With four electrodes placed on the penile shaft bilaterally, CC-EMG was recorded monopolarly for 30 minutes during flaccidity. After evaluation of the recordings by visual inspection, CC-potentials were analyzed using cross- and autocorrelation techniques. The parameters evaluated were amplitude, duration, dominant frequency (DF), and maximum cross-correlation coefficient (Rmax) of CC-potentials recorded from proximal and distal parts of the CC.

MAIN OUTCOME MEASURES

Comparison of the values of parameters amplitude, duration, DF, and Rmax between patient and control groups.

RESULTS

A total of 119 patients with ED and 43 men with reported normal erectile function were studied. Thirteen out of 14 patients with severe penile fibrosis did not show any distinguishable CC-potential. Patients with CAI had significantly decreased amplitude compared with the potent controls, as well as the patients with CVCM but without proven CAI. Significantly decreased amplitude and Rmax were detected in ED patients following RRP compared with the controls.

CONCLUSIONS

Corpus cavernosum electromyography performed with the revised methodology is able to discriminate ED patients with conditions that are associated with cavernous smooth muscle degeneration and/or autonomic neuropathy from men with reported normal erectile function.