Transcranial Direct Current Stimulation (tDCS) vs Trans-spinal Direct Current Stimulation (tsDCS) for Endometriosis-related Chronic Pelvic Pain Treatment: A Single Center, Prospective, Randomized, Controlled, Parallel Group Pilot Study

• 2 groups of 5 HV will receive tDCS or tsDCS (2mA, anodal, 20min) and the thermonociceptive threshold will be measured before and after the stimulation over the abdomen (hypogastric). The HAD scale and SF-36 will also be tested.

The treatment(s) that produces the greatest increase in pain thresholds will be chosen to treat 10 patients.

• 10 patients suffering from endometriosis-related chronic pelvic pain will be treated by the most efficient treatment (tDCS or tsDCS) for 4 weeks (5 daily 20-min sessions per week), or, if no treatment modality was superior in HV, 5 patients will be treated by tDCS and 5 by tsDCS. Patients will fill in daily a dedicated diary 2 weeks before treatment, during the4-week treatment period and after this period as long as their pain level remains below 80% of their baseline pain intensity (VAS). Analgesic intake will also be monitored as well as HAD and SF-36 scores.