Stellate Ganglion Blockade for Refractory Chronic Migraine

Migraine is a common neurological disorder, and approximately 8% of patients develop chronic migraine (CM), defined as headache occurring on 15 or more days per month for more than three months, with at least 8 days fulfilling migraine criteria. Chronic migraine is associated with substantial disability and reduced quality of life.

In patients who do not respond adequately to preventive pharmacological therapies, interventional procedures such as greater occipital nerve blocks, sphenopalatine ganglion blocks, pulsed radiofrequency procedures, and botulinum toxin injections may be considered. However, a subset of patients continues to experience persistent and disabling symptoms despite these interventions.

The stellate ganglion is formed by the fusion of the inferior cervical and first thoracic sympathetic ganglia and plays a key role in cervical sympathetic outflow. Stellate ganglion block (SGB) involves the injection of local anesthetic around the stellate ganglion to temporarily inhibit sympathetic activity. Ultrasound guidance allows real-time visualization of anatomical structures, reduces the risk of vascular injury, and avoids radiation exposure.

In this study, SGB is performed under sterile conditions with continuous monitoring and real-time ultrasound guidance. A linear ultrasound probe is positioned at the level of the sixth cervical vertebra to identify relevant anatomical structures. A 25-gauge needle is advanced using an in-plane technique, and 5 mL of 1% lidocaine is administered after confirming correct placement. For bilateral headache, alternating bilateral applications are performed with an interval between sides.

The primary aim of the study is to evaluate the effect of ultrasound-guided SGB on Monthly Headache Days in patients with treatment-resistant chronic migraine. Secondary aims include evaluation of pain intensity, headache-related disability, analgesic use, patient-reported global improvement, and safety outcomes.

The protocol was amended with institutional ethics committee approval prior to completion of data analysis to extend follow-up to six months and to redefine the primary outcome as change in Monthly Headache Days.

Inclusion criteria

• 18- 65 years of age, diagnosed with chronic migraine in accordance with ICHD-3 criteria,
• used migraine preventive medication drugs and
• other interventional algologic treatments that have been applied at least three months ago with insufficient benefit are volunteer patients.

Exclusion criteria

• Migraine according to ICHD-3 criteria has a history of primary headache other than migraine,
• migraine preventive interventional treatment within the last 3 months and/or botulinum toxin A, nonpharmacological treatment (acupuncture, ozone, cognitive behavioral therapy, etc.),
• injection infection at the site,
• pregnancy or suspected pregnancy,
• known allergy to local anesthetic drugs with a history of malignancy or cranial/cervical surgery,
• bleeding-coagulation disorder or oral anticoagulants,
• comorbid diseases that may cause headache (uncontrolled hypertension, intracranial lesions),
• with diseases that may prevent compliance with treatment (psychiatric disorder, dementia) and
• patients who did not accept the planned interventional treatment were excluded from the study will be released.