Greater occipital nerve block to relieve headaches from spontaneous intracranial hypotension

Role of Greater Occipital Nerve Block in Headache From Spontaneous Intracranial Hypotension: a Prospective Observational Study

This will try a bilateral ultrasound-guided greater occipital nerve block in adults with spontaneous intracranial hypotension to see if it quickly reduces upright headache.

Quick facts

• Study type: Observational
• Enrollment: 34 (estimated)
• Ages: 18 Years and up
• Sex: All
• Sponsor: University Health Network, Toronto (Academic / other)
• Locations: 1 site (Toronto, Ontario)
• Trial ID: NCT06374524 on ClinicalTrials.gov

What this trial studies

This is a prospective observational project enrolling 34 adults with spontaneous intracranial hypotension managed at a single tertiary center. Participants receive an ultrasound-guided bilateral greater occipital nerve block with a 5 mL injectate of local anesthetic plus steroid and there is no control group. The primary outcome is change in headache intensity 30 minutes after the injection, with secondary outcomes that track pain, onset time, sitting endurance, associated CNS symptoms, emotional functioning, patient satisfaction, analgesic use, and side effects through 14 days. The goal is to characterize short-term symptomatic benefit and safety while patients await definitive CSF-leak treatments.

Who should consider this trial

Good fit: Adults (over 18) with a diagnosis of spontaneous intracranial hypotension by ICHD-3 criteria who have upright pain intensity greater than 4/10 and no contraindications to the injection are ideal candidates.

Not a fit: Patients with contraindications to injection (active infection, allergy, steroid contraindication), those on high-dose opioids (OME ≥50 mg/day), or whose headache is not orthostatic are unlikely to receive benefit from this approach.

Why it matters

Potential benefit: If successful, the injection could provide rapid short-term relief of orthostatic headache and improve sitting tolerance and daily function while awaiting definitive leak repair.

How similar studies have performed: Small case series and observational reports suggest occipital nerve blocks can provide short-lived headache relief in SIH and related headaches, but high-quality evidence is limited.

Eligibility criteria

Inclusion criteria

1. Adults of \> 18 years of age
2. Diagnosis of SIH, according to the International Classification of Headache Disorder (ICHD-3) classification (2)
3. Characteristics of pain:

   1. Baseline pain intensity NRS \> 4/10 (in upright position)

Exclusion criteria

1. Contraindications to GONB: ongoing infection (systemic or located at the site of injection), intake of anticoagulants (not aspirin), allergy to injectate, contra-indication to injectate of steroids
2. Any significant cognitive or language barrier that impedes participation
3. Patients taking opioid medications with daily Oral Morphine Equivalent (OME) of 50 mg or higher
4. Patient refusal

Where this trial is running

Toronto, Ontario

• Toronto Western Hospital — Toronto, Ontario, Canada (Recruiting)

Study contacts

• Study coordinator: Anna Kalleitner, RN

Conditions Spontaneous Intracranial Hypotension