Is It Migraine or SIH? When Headaches Need Specialist Review
Headaches are extremely common, and for most people, they are caused by migraine or other primary headache disorders. However, for a small number of patients, headaches that behave differently may be linked to a condition called spontaneous intracranial hypotension (SIH).
Because SIH can share symptoms with migraine, many people understandably feel anxious when researching their symptoms online. It is important to emphasise that SIH is rare, and the purpose of this article is to explain how specialists differentiate between SIH and migraine, not to encourage self-diagnosis.
As Mr Gordan Grahovac, Consultant Neurosurgeon and Complex Spinal Surgeon in London, explains:
“The vast majority of headaches we see are not caused by SIH. But when headache patterns don’t fit typical migraine features, when headaches get worse during standing and improve during laying down ‘’orthostatic headaches’’ careful specialist assessment helps us reach the right diagnosis and reassure patients.”
What Is Migraine?
Migraine is a neurological condition that causes recurrent headaches, often accompanied by additional symptoms.
Typical migraine features include:
Moderate to severe headache pain, often throbbing
Sensitivity to light or sound
Nausea or vomiting
Visual disturbances (aura) in some patients
Headaches lasting hours to days
Migraine symptoms may worsen with activity, stress, poor sleep, dehydration, or hormonal changes. Importantly, migraine does not depend on body position, meaning pain does not reliably improve when lying flat or worsen when upright.
What Is Spontaneous Intracranial Hypotension (SIH)?
SIH occurs when cerebrospinal fluid (CSF) leaks from the spinal canal, reducing the volume of CSF in the central nervous system and in acute phase reduce the pressure of fluid that normally cushions the brain and spinal cord.
This pressure change can lead to headaches and other neurological symptoms. SIH is uncommon and often under-recognised early on because symptoms can overlap with migraine.
The Key Difference: Headache Pattern
The most important distinction specialists look for is how the headache behaves, not just how it feels.
Migraine headache pattern
Can occur at any time of day
Not consistently related to posture
Often triggered by stress, light, sound, or food
May improve with migraine-specific medication
SIH headache pattern
Worse when standing or sitting upright
Improves when lying down
Returns within minutes to hours of standing
Often described as pressure-like or pulling
May be accompanied by neck pain, nausea, tinnitus, or visual changes
This positional pattern is the single most important clue that prompts specialists to consider SIH.
Why SIH and Migraine Are Sometimes Confused
Early SIH can resemble migraine, particularly when headaches are severe and persistent. In some cases:
The positional pattern may not be obvious at first
Symptoms fluctuate day to day
Initial scans may appear normal
Your clinician is not aware of SIH
Because of this overlap, diagnosis may take time. This does not mean harm is occurring. Careful observation, follow-up, and specialist input are often what lead to clarity.
How Specialists Investigate SIH
Diagnosis relies on combining symptoms, imaging, and clinical judgement. MRI brain and spine with special protocol and review by neuroradiologists is the first step.
Specialist assessment may include:
MRI of the brain to look for pressure-related changes
MRI of the spine to identify potential leak sites
Dynamic CT myelography or digital subtraction myelography in selected cases
Not all patients with SIH show classic findings immediately. This is why expert interpretation is essential. It is extremely important that imaging is done by neuroradiologist who has vast experience in diagnosis and management of patients with SIH, to reduce the number of inappropriate imaging, radiation exposure and speed up diagnosis of SIH.
Treatment Differences: Migraine vs SIH
Migraine treatment
Lifestyle modification
Preventative medications
Acute migraine therapies
Trigger management
SIH treatment
Bed rest, hydration, and caffeine, with use of soft abdominal binders
CT guided targeted epidural blood patch
CT guided targeted fibrin glue patch in selected cases
Transvenous embolisation in selected cases
Surgical spinal leak repair when required
When SIH is correctly identified, treatment is often highly effective, and many patients experience significant symptom improvement.
When to Seek Specialist Advice
You may benefit from specialist review if:
You have been diagnosed with superficial siderosis
Headaches reliably worsen when upright and improve when lying flat
Suspicion on low pressure on brain MRI or free epidural fluid in the MRI of the spine
Headaches are accompanied by neck stiffness, tinnitus, or visual disturbance
There is a history of previous spinal procedures complicated with CSF leak
For most people, specialist assessment provides reassurance, even when SIH is ruled out.
What This Means for Patients
Most headaches are not caused by SIH. Migraine remains far more common and manageable with the right care. However, understanding how specialists distinguish between migraine and SIH can provide clarity and reassurance for patients whose symptoms feel different or persistent.
If you are unsure, specialist assessment can help confirm the cause of your symptoms and guide appropriate treatment with confidence and calm.
Specialist Care With Mr Gordan Grahovac
Mr Gordan Grahovac is a Consultant Neurosurgeon and Complex Spinal Surgeon with extensive experience in diagnosing and treating:
Spontaneous intracranial hypotension (SIH)
Spinal CSF leaks
Complex dural defects
Conditions misdiagnosed as migraine
He works closely with specialist neuroradiologists (Dr Lalani Carlton Jones), neurologist (Dr Alex Nesbitt) to ensure accurate diagnosis and tailored treatment, whether surgical or non-surgical.
Frequently Asked Questions About SIH
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SIH is rarely life-threatening, due to severe complication. When diagnosed and treated appropriately, outcomes are generally very good.
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In some cases symptoms can improve and patients can be mildly symptomatic, but in majority of the cases symptoms persist and can cause prolonged discomfort.
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No. Imaging findings of the brain can be subtle or normalise over time. Diagnosis relies on the full clinical picture, and MRI of the whole neuroaxis.
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Yes. Some patients have migraine and later develop SIH, which can complicate diagnosis and requires careful evaluation.
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Improvement with rest alone is common and does not automatically indicate SIH. Persistent, clearly positional headaches are the key concern.
