Spontaneous Intracranial HypotensionNCT06374524
Greater Occipital Nerve Block for Spontaneous Intracranial Hypotension
An observational study of Spontaneous Intracranial Hypotension, run by University Health Network, Toronto at 1 site in Canada.
Trial summary
Spontaneous Intracranial Hypotension (SIH) is a debilitating neurological disorder caused by a cerebrospinal fluid leak (CSF), with an estimated incidence of 5 per 100,000 persons per year, of which mostly women between the ages of 35 years and 55 years. Read more about this study
- Who is it for?
- Ages 18 years and older
- Conditions the study is for
- Spontaneous Intracranial Hypotension
- What is being tested?
- greater occipital nerve block
- Type of treatment
- Surgery or procedure
- How many people
- 34 participants
- Where
- 1 siteCanada
- Study dates
- 1 Aug 2024to 31 Dec 2027
- Phase
- Observational
- Are there results?
- Not yet: the study is under way
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 years and older
- All sexes
- No healthy volunteers
- Adult, Older adult
Study population: Patients with documented SIH will be recruited from the Toronto Western Hospital Intracranial Hypotension Clinic and enrolled after consent is obtained.
Who may be able to join
- Adults of > 18 years of age
- Diagnosis of SIH, according to the International Classification of Headache Disorder (ICHD-3) classification (2)
- Characteristics of pain:
- Baseline pain intensity NRS > 4/10 (in upright position)
Who cannot join
- 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
- Any significant cognitive or language barrier that impedes participation
- Patients taking opioid medications with daily Oral Morphine Equivalent (OME) of 50 mg or higher
- Patient refusal
Trial locations and contacts
1 site in 1 country. Contact the study team or a site near you to ask about taking part.
Canada1 site, 1 recruiting
- Recruiting
Toronto Western Hospital
Toronto, Ontario, M3A2L8
Anna Kalleitner, RN, 416-603-5800 ext. 8830, Anna.Kalleitner@uhn.ca
Anuj Bhatia, MD, PhD
About this study
Official title: Role of Greater Occipital Nerve Block in Headache From Spontaneous Intracranial Hypotension: a Prospective Observational Study
Spontaneous Intracranial Hypotension (SIH) is a debilitating neurological disorder caused by a cerebrospinal fluid leak (CSF), with an estimated incidence of 5 per 100,000 persons per year, of which mostly women between the ages of 35 years and 55 years. The typical presentation is moderate-to-severe orthostatic headache and several other possible neurological symptoms, that significantly impact patients' quality of life.
Treatment of SIH usually starts with conservative measures, consisting of strict supine bed rest, hydration, caffeine, and simple analgesics. The vast majority of patients will require invasive treatments for their CSF leak, such as epidural blood patches, fibrin glue patches, endovascular coiling, and/or surgical repair. These specialized treatments are only offered in tertiary care centers and require specialized personnel and resources, which implicates a certain waiting time for the patients before permanent treatment is offered. In the meantime, due to the lack of an effective and accessible alternative, patients continue to suffer.
Read more
The greater occipital nerve block (GONB) has been reported as a simple, safe, and effective treatment to provide short-to-intermediate term relief of migraine, cervicogenic headache, cluster headache, occipital neuralgia, and more recently, post-dural puncture headaches (PDPH). As the pathophysiology of intracranial hypotension caused by SIH or PDPH is very similar, it is stipulated that the effect of GONB will be similar for SIH patients. However, to date, no studies exploring the efficacy of GONB for SIH have been performed.
The investigators propose to do a prospective observational study to explore the outcome of GONB for SIH. GONB can serve as a bridge therapy to control the debilitating headache of SIH while patients are awaiting permanent SIH treatment. Moreover, GONB can be performed by physicians of different specialties including neurology, which makes it an accessible treatment for all patients. Lastly, by offering better symptom control, this intervention could potentially restore patients' ability to work and reduce healthcare costs.
Read the detailed description
This a prospective observational study on 34 patients with SIH, recruited from the Toronto Western Hospital Intracranial Hypotension Clinic. Patients will receive an ultrasound-guided bilateral GONB of 5 mls of injectate of mix of local anesthetic with steroid. There is no comparator. Primary outcome is the change in intensity of headache at 30 minutes post-intervention. Secondary outcomes are change in intensity up to day 14 post-intervention, onset of headache, sitting endurance, change in SIH-associated central nervous system (CNS) symptoms, emotional functioning, patient satisfaction, analgesic consumption and side-effect, up to 14 days post-intervention
- Conditions
- Spontaneous Intracranial Hypotension
- Being tested
- greater occipital nerve block
- Medical subject headings
- Intracranial Hypotension
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
greater occipital nerve blockProcedure or surgery
Patients will receive an ultrasound-guided bilateral GONB (distal approach) of 5 mLs of injectate of bupivacaine 0.25% (5 mLs) + depomedrol 40 mg in 1 mL (3 mLs to each side).
What is being measured
The primary outcome is the main question the study is designed to answer.
Change in headache intensity
The difference in the change in intensity of headache, as measured on an 11-point Numerical Rating Scale (NRS), measured 30 minutes after the intervention, after being positioned in an upright position for 10 minutes, compared to baseline.
Measured: 30 minutes post intervention
Secondary outcomes (10)
pain intensity
The difference in the change in intensity of headache, as measured on an 11-point Numerical Rating Scale (NRS) where 0 means no pain and 10 worst pain imaginable
Measured: day 1,3,7,14
Onset of headache
The time of onset or worsening of headache when positioned in a sitting position
Measured: at 30 minutes post-intervention and on the morning of day 1, 3, 7, and 14 post-intervention
Sitting endurance
The duration of tolerance in an upright position (i.e. how long the patient can stay in an upright position until the headache becomes unbearable and urges the patient to lie down))
Measured: at 30 minutes post-intervention and on the morning of days 1, 3, 7, and 14 post-intervention (in minutes
SIH associated central nerve system symptoms, such hearing loss, tinnitus, tremor, balance difficulties
To assess the impact of SIH-associated symptoms such as tinnitus, tremor, and balance abnormalities
Measured: at 30 minutes post-intervention and on days 1, 3, 7, and 14 post-intervention
Level of generalized anxiety
Emotional functioning as measured by the Generalized Anxiety Disorder-7 items (GAD-7)
Measured: at day 14 post-intervention
patient satisfaction
patient impression of change, as measured by the Participant Global Impression of Change (PGIC)
Measured: at day 14 post-intervention
analgesic consumption
Analgesic requirement will be measured daily, by intake frequency and dose of analgesics and average daily oral morphine equivalent (OME) in mg
Measured: daily up to day 14
adverse effects
Measured: daily up to day 14
Level of Pain Catastrophizing
Emotional functioning as measured by the Pain Catastrophizing Scale (PCS)
Measured: at Day 14 post-intervention
Level of depression
Emotional functioning as measured by the Patient Health Questionnaire for Depression-9-items (PHQ-9)
Measured: at Day 14 post-intervention
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted18 Apr 2024
- Study start1 Aug 2024
- Primary completion31 Dec 2027 (estimated)
- Study completion31 Dec 2027 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Spontaneous Intracranial HypotensionStudies of the same condition, open and under way.
- More trials run by University Health Network, TorontoThe sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Observational
- Observational model
- Cohort
- Time perspective
- Prospective
- Enrolment
- 34 participants (estimated)
Sponsor and investigators
- Lead sponsor
- University Health Network, Toronto
- Sponsor type
- University, hospital or other
- Responsible party
- Principal investigator, Anuj Bhatia, University Health Network, Toronto
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT06374524
- Sponsor's protocol ID
- 24-5568
- Status last verified
- Jan 2026
- First submitted
- 15 Apr 2024
- Last updated
- 16 Jan 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No
Study at a glance
From the registry record, last updated by the sponsor on 16 Jan 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Role of Greater Occipital Nerve Block in Headache From Spontaneous Intracranial Hypotension: a Prospective Observational Study
- ClinicalTrials.gov ID
- NCT06374524
- Acronym / sponsor ID
- 24-5568
- Conditions
- Spontaneous Intracranial Hypotension
- Study type
- Observational
- Recruitment status
- Recruiting
- Enrolment
- 34 participants (estimated)
- Lead sponsor
- University Health Network, TorontoUniversity, hospital or other
- Study start
- 1 Aug 2024 (actual)
- Primary completion
- 31 Dec 2027 (estimated)
- Study completion
- 31 Dec 2027 (estimated)
- First posted
- 18 Apr 2024 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
Spontaneous Intracranial Hypotension (SIH) is a debilitating neurological disorder caused by a cerebrospinal fluid leak (CSF), with an estimated incidence of 5 per 100,000 persons per year, of which mostly women between the ages of 35 years and 55 years. The typical presentation is moderate-to-severe orthostatic headache and several other possible neurological symptoms, that significantly impact patients' quality of life.
Treatment of SIH usually starts with conservative measures, consisting of strict supine bed rest, hydration, caffeine, and simple analgesics. The vast majority of patients will require invasive treatments for their CSF leak, such as epidural blood patches, fibrin glue patches, endovascular coiling, and/or surgical repair. These specialized treatments are only offered in tertiary care centers and require specialized personnel and resources, which implicates a certain waiting time for the patients before permanent treatment is offered. In the meantime, due to the lack of an effective and accessible alternative, patients continue to suffer.
The greater occipital nerve block (GONB) has been reported as a simple, safe, and effective treatment to provide short-to-intermediate term relief of migraine, cervicogenic headache, cluster headache, occipital neuralgia, and more recently, post-dural puncture headaches (PDPH). As the pathophysiology of intracranial hypotension caused by SIH or PDPH is very similar, it is stipulated that the effect of GONB will be similar for SIH patients. However, to date, no studies exploring the efficacy of GONB for SIH have been performed.
The investigators propose to do a prospective observational study to explore the outcome of GONB for SIH. GONB can serve as a bridge therapy to control the debilitating headache of SIH while patients are awaiting permanent SIH treatment. Moreover, GONB can be performed by physicians of different specialties including neurology, which makes it an accessible treatment for all patients. Lastly, by offering better symptom control, this intervention could potentially restore patients' ability to work and reduce healthcare costs.
Detailed description
This a prospective observational study on 34 patients with SIH, recruited from the Toronto Western Hospital Intracranial Hypotension Clinic. Patients will receive an ultrasound-guided bilateral GONB of 5 mls of injectate of mix of local anesthetic with steroid. There is no comparator. Primary outcome is the change in intensity of headache at 30 minutes post-intervention. Secondary outcomes are change in intensity up to day 14 post-intervention, onset of headache, sitting endurance, change in SIH-associated central nervous system (CNS) symptoms, emotional functioning, patient satisfaction, analgesic consumption and side-effect, up to 14 days post-intervention
Study design
- Observational model
- Cohort
- Time perspective
- Prospective
Who may qualify
- Ages
- 18 years and older
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
- Study population
- Patients with documented SIH will be recruited from the Toronto Western Hospital Intracranial Hypotension Clinic and enrolled after consent is obtained.
Key inclusion criteria (4 listed)
- Adults of > 18 years of age
- Diagnosis of SIH, according to the International Classification of Headache Disorder (ICHD-3) classification (2)
- Characteristics of pain:
Key exclusion criteria (4 listed)
- 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
- Any significant cognitive or language barrier that impedes participation
- Patients taking opioid medications with daily Oral Morphine Equivalent (OME) of 50 mg or higher
- Patient refusal
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| greater occipital nerve blockPatients will receive an ultrasound-guided bilateral GONB (distal approach) of 5 mLs of injectate of bupivacaine 0.25% (5 mLs) + depomedrol 40 mg in 1 mL (3 mLs to each side). | Procedure or surgery | – |
Primary outcome
Change in headache intensity
Time frame: 30 minutes post intervention
The difference in the change in intensity of headache, as measured on an 11-point Numerical Rating Scale (NRS), measured 30 minutes after the intervention, after being positioned in an upright position for 10 minutes, compared to baseline.
10 secondary outcomes
pain intensity
Time frame: day 1,3,7,14
Onset of headache
Time frame: at 30 minutes post-intervention and on the morning of day 1, 3, 7, and 14 post-intervention
Sitting endurance
Time frame: at 30 minutes post-intervention and on the morning of days 1, 3, 7, and 14 post-intervention (in minutes
SIH associated central nerve system symptoms, such hearing loss, tinnitus, tremor, balance difficulties
Time frame: at 30 minutes post-intervention and on days 1, 3, 7, and 14 post-intervention
Level of generalized anxiety
Time frame: at day 14 post-intervention
patient satisfaction
Time frame: at day 14 post-intervention
analgesic consumption
Time frame: daily up to day 14
adverse effects
Time frame: daily up to day 14
Level of Pain Catastrophizing
Time frame: at Day 14 post-intervention
Level of depression
Time frame: at Day 14 post-intervention
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 16 Jan 2026.
- Individual participant dataSharing planned: No
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part.
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
An observational study of Spontaneous Intracranial Hypotension, run by University Health Network, Toronto at 1 site in Canada.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 4 inclusion and 4 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: looking for participants now, as of the sponsor's last update on 16 Jan 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in Canada. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
Contact Anna Kalleitner, RN (416-603-5800 ext. 8830, Anna.Kalleitner@uhn.ca), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Change in headache intensity (time frame: 30 minutes post intervention). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 16 Jan 2026.