Ultrasound Guided Infratemporal Sphenopalatine Ganglion Supravoltage Versus Standard Voltage Pulsed Radiofrequency for Pain Alleviation in Chronic Refractory Migraine.

Ultrasound Guided Sphenopalatine Ganglion Supravoltage Versus Standard Voltage Pulsed Radiofrequency for Pain Alleviation in Chronic Refractory Migraine. Randomized Double Blind Study

• PRF performed on the sphenopalatine ganglion level under ultrasound guidance.
• Standard voltage PRF parameters: 45 V, 5 Hz frequency, 5 ms pulse width, 360 seconds duration, electrode temperature ≤42°C.
• Supravoltage PRF parameters: Higher voltage than standard (e.g., 60-70 V), with same frequency, pulse width, and duration, maintaining temperature ≤42°C to avoid nerve damage.

Inclusion Criteria:

• Diagnosis of chronic migraine according to International Classification of Headache Disorders criteria (≥15 headache days/month for >3 months, including ≥8 migraine days/month) documented by Completion of 4-week prospective baseline headache diary immediately preceding randomization

  • Failure of ≥2 classes of preventive pharmacological migraine medications (e.g., beta-blockers, antiepileptics, antidepressants...) to get clinically meaningful response ( defined as ≥50% reduction in monthly migraine days), at standard therapeutic doses (Beta-blockers (e.g., propranolol ≥160 mg/day, metoprolol ≥100 mg/day, Antiepileptics (e.g., topiramate ≥100 mg/day, valproate ≥500 mg/day, Tricyclic antidepressants (e.g., amitriptyline ≥50 mg/day, SNRIs (e.g., venlafaxine ≥150 mg/day ) for at least 8 weeks or ≥12 weeks in case of CGRP ).
  • Stable preventive migraine therapy for at least 4 weeks prior to enrollment.
  • MIDAS score ≥11 indicating moderate to severe disability.
  • Ability and willingness to maintain a daily headache diary throughout the study period.
  • Ability to provide written informed consent. Positive response (≥50% pain reduction within 30-60 minutes) to diagnostic INFRATEMPORAL sphenopalatine ganglion block using 2% lidocaine (2 mL) infrazygomatic approach

Exclusion Criteria:

• Medication Overuse Headache per ICHD-3: Simple analgesics (acetaminophen, NSAIDs, non-opioid analgesics) used on ≥15 days per month for >3 months, OR Triptans, ergot derivatives, opioids, or combination analgesics used on ≥10 days per month for >3 months.
• Any secondary headache disorder ( cluster headache, hemiplegic migraine, migraine with brainstem aura (distinct pathophysiology); chronic tension-type headache >10 days/month.
• Any prior SPG block, PRF, radiofrequency thermocoagulation, chemical neurolysis, or neurostimulation of SPG/trigeminal system within 6 month.
• No prior occipital or supra-orbital nerve radiofrequency, cryotherapy, or chemical neurolysis within 3 months
• Use of botulinum toxin (Botox) within 3 months or CGRP monoclonal antibodies within 3 months prior to enrollment.
• Active psychosis, bipolar disorder (current manic/depressive episode), severe depression with suicidal ideation, dementia, or substance use disorder (DSM-5 criteria) within 12 months; PHQ-9 ≥20 or cognitive impairment affecting reporting reliability.
• Cardiac pacemaker, ICD, neurostimulator, or cochlear implant; or ECT.
• Chronic uncontroled hypertension ; history of stroke, intracranial aneurysm, or high risk for cardiovascular events.
• Pregnancy or lactation, Initiation, discontinuation, or modification of hormonal contraceptive therapy within 3 months prior to enrollment.

Coagulopathy (platelets <100,000 or INR >1.5) or ongoing anticoagulation not safely withheld.

-Patient refusal.