Efficacy and Safety of Transcutaneous Auricular Vagus Nerve Stimulation for Postoperative Headache Following Stent-Assisted Coiling of Unruptured Intracranial Aneurysms (IMPACT-HT)

The goal of this clinical trial is to evaluate the efficacy and safety of transcutaneous auricular vagus nerve stimulation (taVNS) in reducing postoperative headache among adults undergoing stent-assisted coiling for unruptured intracranial aneurysms (UIAs). The study will include male and female participants aged 18 to 80 years who are scheduled for endovascular treatment of UIAs with stent-assisted coiling or flow diverter devices.

The main questions it aims to answer are:

• Can taVNS reduce the incidence of headache within 90 days after stent-assisted embolization of UIAs?
• Is taVNS safe and well-tolerated in this patient population? Researchers will compare patients receiving active taVNS to those receiving sham stimulation to determine if taVNS leads to fewer postoperative headaches and reduced need for analgesic medications.

Participants will:

• Wear a taVNS device on the left earlobe (active group) or cymba conchae (sham group) starting 1 day before the procedure
• Receive 30-minute stimulation sessions, twice daily, until postoperative day 5
• Undergo follow-up assessments of headache occurrence, pain intensity, analgesic use, and any adverse events through day 90 after the procedure

Study Overview

• Status: Recruiting
• Conditions: Headache; Unruptured Intracranial Aneurysm; Vagus Nerve Stimulations
• Intervention / Treatment: Device: Transcutaneous Auricular Vagus Nerve Stimulation; Device: Sham transcutaneous auricular vagus nerve stimulation

• Study Type: Interventional
• Enrollment (Estimated): 440
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Qingyuan Liu, M.D.; Phone Number: +86-13260457220; Email: 13260457220@163.com

Study Locations

• China
  • Beijing Municipality
    • Beijing, Beijing Municipality, China
      • Recruiting
      • Capital Medical University Affiliated Beijing Tiantan Hospital
      • Principal Investigator: Shuo Wang, M.D.
      • Contact: Qingyuan Liu, M.D.; Phone Number: +86-13260457220; Email: 13260457220@163.com

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

1. Age 18-80 years
2. Diagnosed with unruptured intracranial aneurysm confirmed by imaging
3. Planned to undergo stent-assisted coiling or flow diverter embolization
4. Signed informed consent

Exclusion Criteria:

1. History of SAH, ICH, brain tumor, major trauma, substance abuse, syncope, or seizures
2. Recurrent/traumatic/infectious/myxomatous aneurysms
3. Primary headache disorders (e.g., migraine, cluster headache, trigeminal neuralgia) not attributed to UIA
4. Previous vagotomy, migraine surgery, or implanted neurostimulators
5. Other concurrent electronic/implantable devices (e.g., pacemakers, neurostimulators)
6. Clinically significant hypotension, congenital heart disease, severe arrhythmia, unstable angina, or recent MI
7. Inability to follow up due to severe psychiatric disorder or refusal
8. Skin lesions at taVNS placement site
9. Pregnant or lactating
10. Participation in other trials

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Double

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Experimental Group; Participants will receive transcutaneous auricular vagus nerve stimulation via a taVNS device applied to the left cymba conchae starting 24 hours before surgery to 5 days after surgery. Stimulation will be administered twice daily, with a 12-hour interval between sessions. Parameters: pulse width of 200-300 µs at 25 Hz and a biphasic pulse interval of 30 s ON and 30 s OFF. The stimulus intensity of the tVNS varied between individuals and is set to the average level, which is defined by the level above the detection threshold but below the pain perception threshold.	Device: Transcutaneous Auricular Vagus Nerve Stimulation; Participants will receive transcutaneous auricular vagus nerve stimulation via a taVNS device applied to the left cymba conchae starting 24 hours before surgery to 5 days after surgery. Stimulation will be administered twice daily, with a 12-hour interval between sessions. Parameters: pulse width of 200-300 µs at 25 Hz and a biphasic pulse interval of 30 s ON and 30 s OFF. The stimulus intensity of the tVNS varied between individuals and is set to the average level, which is defined by the level above the detection threshold but below the pain perception threshold.
Sham Comparator: Control Group; Sham stimulation with the device placed at the left cymba conchae without electrical current. Stimulation parameters, frequency and duration are identical to the experimental group.	Device: Sham transcutaneous auricular vagus nerve stimulation; Participants will receive transcutaneous auricular vagus nerve stimulation but without electrical current via a taVNS device applied to the left earlobe starting 24 hours before surgery twice daily until postoperative day 5. Stimulation parameters, frequency and duration are identical to the experimental group.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Primary efficacy outcome: Incidence of headache within postoperative day 5 to day 90	Incidence of headache within postoperative day 5 to day 90, defined as headache lasting ≥4 hours or requiring acute analgesic treatment, excluding secondary causes (e.g., hemorrhage, trauma).	Postoperative day 5 to day 90
Primary safety outcome: Incidence of taVNS-related adverse events	Incidence of taVNS-related adverse events: Bradycardia (HR < 50 bpm for ≥5 minutes); Hypotension (MAP drop > 20 mmHg or >30% from baseline); ECG abnormalities (ST changes or arrhythmias confirmed by cardiologist); Symptomatic cerebral infarction (NIHSS score increase ≥2 with imaging evidence within 24h); Local skin complications (redness, pain, injury ≥24h)	From 24 hr before surgery to 5 days after surgery
Number of days with moderate to severe headache (VAS ≥ 4) between postoperative day 5-90	Number of days with moderate to severe headache (VAS ≥ 4) between postoperative day 5-90	Postoperative day 5-90

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Headache incidence within postoperative day 5-30	Incidence of headache within postoperative day 5 to day 30, defined as headache lasting ≥4 hours or requiring acute analgesic treatment, excluding secondary causes (e.g., hemorrhage, trauma).	Postoperative day 5 to day 30
VAS (Visual Analog Scale) scores on postoperative day 30 and 90	VAS (Visual Analog Scale) scores on postoperative day 30 and 90. Visual Analog Scale (range: 0-10), where 0 indicates no pain and 10 indicates the worst imaginable pain; higher scores indicate worse pain outcomes.	Postoperative day 30 and 90
Number of days with moderate to severe headache (VAS ≥ 4) between postoperative day 5-30	Number of days with moderate to severe headache (VAS ≥ 4) between postoperative day 5-30	Postoperative day 5-30
Postoperative day 5 levels of blood inflammatory cytokines	Postoperative day 5 levels of blood inflammatory cytokines	Postoperative day 5
Postoperative day 90 levels of blood inflammatory cytokines	Postoperative day 90 levels of blood inflammatory cytokines	Postoperative day 90

Collaborators and Investigators

• Sponsor: Beijing Tiantan Hospital

Study record dates

Study Major Dates

• Study Start (Actual): September 30, 2025
• Primary Completion (Estimated): July 1, 2027
• Study Completion (Estimated): July 1, 2027

Study Registration Dates

• First Submitted: January 22, 2026
• First Submitted That Met QC Criteria: March 13, 2026
• First Posted (Actual): March 18, 2026

Study Record Updates

• Last Update Posted (Actual): March 18, 2026
• Last Update Submitted That Met QC Criteria: March 13, 2026
• Last Verified: August 1, 2025

More Information

Terms related to this study

• Keywords: Vagus Nerve Stimulation; Unruptured Intracranial Aneurysm; Postoperative Headache
• Additional Relevant MeSH Terms: Pain; Neurologic Manifestations; Pathological Conditions, Signs and Symptoms; Signs and Symptoms; Headache
• Other Study ID Numbers: KY2025-284

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No