Real-Time Hemodynamic Changes in the Prefrontal and Bilateral Temporal Cortices During Intradermal Acupuncture for Major Depressive Disorder: A Prospective, Single-Center, Controlled Trial Protocol.

Background: Major depressive disorder (MDD) is highly prevalent, affecting more than 300 million individuals worldwide, and its occurrence may be related to the abnormality of the prefrontal cortex and bilateral temporal cortex. Acupuncture, rooted in the theories of acupoints and meridians, has demonstrated its efficacy in regulating cortical blood flow (CBF) in the brains of MDD patients. As one form of acupuncture, intradermal acupuncture (IA) can alleviate clinical symptoms such as depressive mood and insomnia in MDD patients. However, it remains unknown whether IA will have a specific effect on the prefrontal cortex and bilateral temporal cortex in MDD patients. Methods: In total, 60 participants will be recruited: 20 healthy control participants and 40 MDD patients. All healthy control participants will be allocated to the control group, whereas the 40 MDD patients will be randomly divided into two groups: the gallbladder meridian acupoint (GBA) group and the non-acupoint (NA) group, at a 1:1 allocation ratio. All groups will undergo a one-time IA intervention while their cortical activity is monitored using functional near-infrared spectroscopy (fNIRS). Total hemoglobin, oxygenated hemoglobin, and deoxygenated hemoglobin of the prefrontal and bilateral temporal cortices will be measured by fNIRS during the test procedure. Discussion: This trial aims to use fNIRS to compare real-time hemodynamic changes in the prefrontal and bilateral temporal cortices of healthy individuals and MDD patients during IA. The primary objective is to investigate whether MDD patients exhibit specific real-time responses to IA stimulation in these brain regions. The findings from this study will provide clinical data and a possible theoretical basis for the assumption that stimulation of IA may treat MDD by modulating the relevant brain regions. Trial Registration: The study protocol has been registered in the clinicaltrials.gov with the code NCT05707299.