Erectile dysfunction (ED) after radical prostatectomy (PTR) is a specific form of ED, having a causal factor (surgical trauma), as well as previous multifactoriality. Electrical stimulation is beneficial for treating smooth muscle dysfunctions and could be used in the treatment of ED, caused by the cavernous smooth muscle anomaly. In studies on cavernous smooth muscle, there is knowledge that the growth of smooth muscle can be induced. Microcurrent stimulation of striated muscles is an established method for muscle regeneration when applied through surface electrodes activating sensory and motor nerve fibers. Bioelectrical stimulation (BES) can restore function as it modulates nervous system responses to stimuli, as by neuromodulation, or accelerate regeneration of injured peripheral or central nerves by regenerative electrical stimulation. This trial aimed to study the effects of the use of BES in the recovery of erectile function in a group of ED patients. We hypothesize that micro-current and low-frequency levels of BES deliver a set of precise signals to target regenerative and reparative proteins and can be associated with significant improvement in all the endpoints used to assess ED with no reported adverse events.

Quasi-experimental study approved by the Research Ethics Committee of Universidade Inspirar, (N°3.076.79) and registered with Clínical Trials (N° NCT05118607). Included were men who underwent open RP for localized prostate adenocarcinoma (clinical and pathological stage ≤ T2, N0, M0), between 40 and 75 years of age with a diagnosis of post-RP ED (IIFE5 score less than 22) followed in the private urology physician, who agreed to participate in the study and who completed informed consent. Each patient served as their control, using the validated questionnaires, International Index of Erectile Function -IIFE5 and Erection Hardness Score (EHS). The intervention period was 8 weeks. There were 6 months of follow-up after the end of treatment to assess the duration of benefit.
The assessment was also carried out before the intervention period (pre-treatment), after the 8-week intervention period (post-treatment), and at the end of follow-up, 6 months after completing the treatment.
The intervention consisted of applying low-intensity transcutaneous penile electrical stimulation, below the motor threshold, that is, there was no muscle contraction during application, a criterion assessed individually, and using low frequency alternating between 10 Hz and 300 Hz. The sessions lasted 45 minutes and were carried out twice a week.
The current was applied through two self-adhesive electrodes from the brand V Trodes (Anaheim, United States), measuring 3 cm each, placed on the surface of the dorsum of the penis, one electrode was placed at the base of the penis, while the second was placed distal to the penis. first and connected to a Mettler model 240 bioelectrical stimulator, which was programmed for five types of low-frequency current that were switched every 5-15 minutes.
Analyzes were performed using the SPSS 22.0 statistical program (SPSS, Chicago, Illinois). The analyzed data were presented in absolute and relative frequency, mean and standard deviation, or median and interquartile range 25-75%, according to the normality of the data, which was verified by the Shapiro-Wilk test. The Friedman test with Dunn’s post-test was used for comparisons between evaluation periods.

Ten patients were selected, treated, evaluated, and included in this study. The Tabel 1 shows demographic and clinical data of the patients. In Table 2 we check the comparison of the mean IIFE-5 and EHS scores over the baseline and pre-intervention periods; post-intervention; and follow-up. A significant difference was found for both (p<0.0001).
This study analyzed microcurrent as an alternative treatment for ED after PR, demonstrating it to be effective according to the IIFE-5 questionnaire (p<0.001) and EHS (p<0.001). Table 3 compares the IIEF-5 and EHS scores over time.

Studies have demonstrated the benefits of microcurrent for various health conditions and the healing process. However, to our knowledge, none have explored its use for treating erectile dysfunction in humans. Superficial microcurrent stimulation resembles the currents generated in the body during healing, and intensifies tissue bioactivity at the cellular level, stimulating cellular physiology and growth (1).The stimulation of ion channels and cellular communication can regulate the electrical environment of cells and promote their activity. Low-frequency electrical stimulation in an animal model resulted in beneficial effects after cavernous nerve injury, increasing erectile function, also showing a protective effect on penile tissues and nerves, with preservation of oxidative stress, inflammation, loss of smooth muscle cells, as well as fibrosis of erectile tissue, preventing apoptosis of the nitrergic fibers of the cavernous nerve and maintaining the myelination of nerve fibers (2). Thus supporting the use of low-frequency electrical stimulation in penile rehabilitation, giving the potential to reduce the discomfort of post-prostatectomy ED.
Although there are penile rehabilitation methods available, there is no definitive evidence that any particular strategy is the most effective in providing unassisted erections. 5-Phosphodiesterase Inhibitors (IPDE5) can help relax smooth muscles, increase blood flow to the corpora cavernosa, and prevent fibrosis. Combining microcurrent therapy with IPDE5 can be a viable alternative for post-prostatectomy rehabilitation (3). 
The use of microcurrent was effective for the treatment of patients with ED after open RP. Furthermore, its benefits proved to be long-lasting after a 6-month follow-up. The limitations of this study are the limited number of patients, the clinical aspects related to RP that are difficult to standardize, and the lack of a histological or vascular analysis to histologically understand the effect of the current on the patients evaluated.

Microcurrent stimulation had a beneficial effect on ED post-open RP assessed by the IIFE-5 and EHS after the 8-week intervention period.Use as an isolated treatment or in combination with other treatments already used may be a promising proposal. Therefore, controlled and randomized studies must be carried out.

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