Repetitive Transcranial Magnetic Stimulation Therapy (rTMS) for Endometriosis Patients with Refractory Pelvic Chronic Pain: A Pilot Study

Abstract

Endometriosis concerns more than 10% of women of reproductive age, frequently leading to chronic pelvic pain. Repetitive transcranial magnetic stimulation (rTMS) over the primary motor cortex (M1) induces an analgesic effect. This effect on chronic pelvic pain is yet to be evaluated. The objective of this study was to assess the feasibility and effect of rTMS to reduce pain and improve quality of life (QoL) in patients with chronic pelvic pain due to endometriosis. This pilot, open-labelled prospective trial examined treatment by neuronavigated rTMS over M1, one session per day for 5 consecutive days. Each session consisted of 1.500 pulses at 10 Hz. We assessed tolerance, pain change and QoL until 4 weeks post treatment with a primary endpoint at day 8. Twelve women were included. No patients experienced serious adverse effects or a significant increase in pain. Nine women reported improvement on the Patient Global Impression of Change with a reduction in both pain intensity and pain interference (5.1 ± 1.4 vs. 4.1 ± 1.6, p = 0.01 and 6.2 ± 2.1 vs. 4.2 ± 1.5, p = 0.004, respectively). rTMS appears well tolerated and might be of interest for patients suffering from chronic pelvic pain for whom other treatments have failed. A randomized controlled trial is mandatory before proposing such treatment.

Keywords: endometriosis; pain; transcranial magnetic stimulation.

Figure 1

Overview of the protocol. rTMS: Repetitive transcranial magnetic stimulation; D1: day 1; D8: day 8; D28: day 28. MRI: magnetic resonance imaging.

Figure 2

Evolution of daily pain over time for the five patients with more than 10% reduction at day 8 (D8), day 1 corresponding to the first rTMS session. Pain is noted out of 100.

Figure 3

Evolution of gastrointestinal quality of life (GIQLI) scores before rTMS (baseline) and at day 8 and day 28; day 1 corresponding to the first rTMS session.