{
  "abstract": "Introduction Colonoscopy is an essential procedure for the early diagnosis of colorectal conditions; however, over 60% of patients undergoing non-sedated colonoscopy report moderate to severe pain. This study aims to investigate the central analgesic mechanisms of transcutaneous electrical nerve stimulation based on wrist-ankle acupuncture theory (TENS-WAA). A multimodal approach combining electroencephalography (EEG) and functional near-infrared spectroscopy (fNIRS) will be employed to assess pain-related brain activity, with artificial intelligence applied to model the relationship between objective neurophysiological signals and subjective pain experience.Methods This is a single-centre, randomised, double-blind, controlled trial involving 60 patients undergoing colonoscopy without anaesthesia. Participants will be randomly allocated (1:1) to either an electrical stimulation group receiving TENS-WAA or a sham stimulation group. EEG and fNIRS data will be acquired before, during and after the procedure. The primary outcome is the analysis of EEG-fNIRS signals to characterise cerebral responses associated with pain modulation. Secondary outcomes include patient-reported pain using the Visual Analogue Scale (VAS), total colonoscopy duration and the correlation between EEG-fNIRS indicators and VAS scores. A deep learning framework will be used to enhance pain prediction accuracy.Ethics and dissemination This study has received ethical approval from the Ethics Committee of Changhai Hospital, Shanghai (approval reference CHEC2025-006), and has been registered at ClinicalTrials.gov. Written informed consent will be obtained from all participants. Findings will be disseminated in peer-reviewed academic journals and at relevant scientific conferences, regardless of outcome, contributing to evidence-based, non-pharmacological pain management strategies.Trial registration number ClinicalTrials.gov, NCT06813703.",
  "authors": [
    {
      "affiliations": [
        "University of Shanghai for Science and Technology, Shanghai, China",
        "Department of Rehabilitation Medicine, Changhai Hospital, Naval Medical University, Shanghai, China"
      ],
      "name": "Han Wang"
    },
    {
      "affiliations": [
        "Department of Rehabilitation Medicine, Changhai Hospital, Naval Medical University, Shanghai, China"
      ],
      "name": "Xiaonan Huang"
    },
    {
      "affiliations": [
        "Shanghai University of Sport, Shanghai, China"
      ],
      "name": "Lifan Xu"
    },
    {
      "affiliations": [
        "University of Shanghai for Science and Technology, Shanghai, China",
        "Department of Rehabilitation Medicine, Changhai Hospital, Naval Medical University, Shanghai, China"
      ],
      "name": "Siyu Guo"
    },
    {
      "affiliations": [
        "Shanghai University of Sport, Shanghai, China"
      ],
      "name": "Chuyue Gong"
    },
    {
      "affiliations": [
        "Department of Rehabilitation Medicine, Naval Medical Center, Shanghai, China"
      ],
      "name": "Cai Mengcheng"
    },
    {
      "affiliations": [
        "Shanghai Gener Arfysica Intelligent Healthcare & Brain Science Research Institute, Shanghai, China"
      ],
      "name": "Wei Wang"
    },
    {
      "affiliations": [
        "Department of Colorectal Surgery, Changhai Hospital, Naval Medical University, Shanghai, China"
      ],
      "name": "Hao Wang"
    },
    {
      "affiliations": [
        "Department of Rehabilitation Medicine, Changhai Hospital, Naval Medical University, Shanghai, China"
      ],
      "name": "Fanfu Fang"
    }
  ],
  "title": "Analysis of the analgesic mechanism of TENS-WAA in colonoscopy using the EEG-fNIRS system: a study protocol for a randomised controlled trial",
  "uid": "c5cbf652-62f9-5cea-b555-55478e4ccb96"
}