A 48 yo patient presents to the emergency department with a complaint of a sudden severe exertional frontal headache, that began whilst exercising 4 days previously. The patient describes this as a 10 out of 10 headache that reached its peak within seconds. He has never had a headache like this before and is generally not a headache sufferer.

There was some associated mild photophobia and the patient was nauseated, but there was no emesis. Intitially the headache was bilateral, frontal and pulsatile. Over the next 4 days the headache moved to the right temporal area and the patient now complains of pain to palpation of a small area over the right temporal region.

He presents to the emergency department as the right temporal pain is persisting and he still has mild photophobia.

On examination, the vitals were normal. He was afebrile, with a heart rate of 64 beats per minute and a blood pressure of 138/56 and oxygen saturations of 96% on room air. He was oriented to person place and time, with normal speech and memory function. There was no neck stiffness. Cranial nerves were normal, as were visual fields. Fundi were normal. Upper and lower limb examination was essentially normal. There was some mild tenderness to palpation over the right temporal region. Heart sounds were dual, chest was clear and abdomen was soft. There was no rash.

The patient had basic blood workup with a FBC, EUC, LFT, plus CRP and ESR. We also performed a CTA/ CTV- see why in the reviews below and see what happenned to this patient at the end of the discussion below.

Review the summary of potential causes of Thunderclap Headache below. Members can listen to the PODCAST lecture
Find out what happenned to the patient below.

 

What is the definition of a thunderclap headache?

The International Headache Society describes it as: “headache that is severe in intensity, abrupt in onset (peaking in intensity in less than 1 minute), lasts at least 5 minutes, and is not accounted for by another diagnosis.

The Differential Diagnoses of a Thunderclap Headache?

1.Aneurysmal Subarachnoid Heamorrhage

Thunderclap headaches also known as warning leak headaches associated with aneurysmal subarachnoid haemorrhage peak within 1 minute of onset. True or False?
False: Regardless of the definition above, 15% of patients with an aneurysmal subarachnoid haemorrhage have headache onset peak after 1 minute and up to 60 minutes.

Can patients with aneurysmal subarachnoid haemorrhage present with only headache?
Up to 7% of patients present with a solitary thunderclap headache and no neurology.

Is a CT Non-contrast scan of the brain an adequate investigation to make a diagnosis of subarachnoid haemorrhage?
A CT performed within 6 hours of headache onset has a high sensitivity and can be used to rule out a subarachnoid haemorrhage.

We cannot rule out subarachnoid haemorrhage after 6 hours. The sensitivity of the scan falls significantly over time. An aneurysm needs to be ruled out by lumbar puncture or CT angiography, both of which have pros and cons.

Specifics to look for in the presentation

  1. Hypertension
  2. Neck pain / meningism
  3. Loss of Consciousness
  4. Vomiting
  5. Retinal Haemorrhage
  6. Look for CN III being affected

Investigations

  • CT Brain if presenting < 6 hours after onset
  • If presenting > 6 hours. Lumbar puncture or CT angiogram, which is becoming more common (read the review of current practice in suspected subarachnoid haemorrhage in The SHED Study)
    • If Cavernous Venous Sinus Thrombosis (CVST) (see below is a differential ensure that the venous sinuses are looked at. This may require a dedicated CT venogram, however can be viewed on angiogram.

Is an aneysmal subarachnoid haemorrhage the only cause of a subarachnoid bleed?
To complicate matters there non-aneurysmal, non-traumatic causes of subarachnoid haemorrhage. These include:

  • Reversible Cerebral Vasoconstriction Syndrome
  • Cervical artery dissection
  • Cerebral venous sinus thrombosis
  • Perimesencephalic Bleed
  • AVMs

Other Causes of Thunderclap Headache

2.Reversible Cerebral Vasoconstriction Syndrome (RVCS)

It can present with a thunderclap headache and is associated with an emotional, physical or medical trigger. It is more common in women than men and patients usually report multiple thunderclap headaches over days or weeks. However this can be the first headache, that the patient presents with.

The condition results in multifocal vasoconstriction of the intracranal arteries. About one third of patients with will have a convexal subarachnoid haemorrhage. It is characterised by reversible and fluctuating narrowing of the intracranial arteries.

Specifics to look for in the presentation

  1. There is a vasoconstrictive trigger(emotional, physical and even medical) prior to headaches
  2. Multiple thunderclap headaches over days to weeks is pathognomonic- However we need to remember that this may be the first headache

Investigations

  • CT angiography or MR angiography

    • Beware as these may be normal early in the presentation.

3.Cerebral Venous Sinus Thrombosis (CVST)

Listen to the 3 minute podcast on Cavernous Sinus Thrombosis by Dr Joe Nemeth.

Up to 15% of patients with CVST will present with a thunderclap headache. Patients can have a convexal subarachnoid haemorrhage.

Specifics to look for in the presentation

  1. It is more common in young adults (<50) and females
  2. The presentation depends on the location of the thrombus
  3. Presentation may be of an insidious headache, then a sudden severe component.
  4. Risk factors include:
    1. Prothrombotic state
      1. Oestrogen intake
      2. Pregnancy especially 3rd trimester and post-partum
      3. Head and Neck infections
    2. Thrombophilia
    3. Trauma, ie mechanical or iatrogenic(neurosurgical procedures)
  5. Patients can present with:
    Visual problems including decreased vision and proptosis
  6. Sensory and motor deficits
  7. Seizures
  8. Aphasia(Left Transverse sinus thrombosis)

Investigations

  • CT or MR venography

    • Beware as these may be normal early in the presentation.

4.Arterial Dissection

Thunderclap headache has been reported in both carotid and vertebral artery dissections. It can also cause convexal subarachnoid hemorrhage. In many cases there will be stroke symptoms but not always.

Specifics to look for in the presentation

  1. Neck pain due to cervical artery dissection
  2. Background of trauma
  3. Headache may precede or occur with stroke symptoms.
  4. Look for a Horner’s Sydrome

Investigations

  • CT or MR angiography

5.Posterior Reversible Encephalopathy Syndrome

This can also cause severe headache, however the onset is not sudden. Patients also commonly have altered vision, seizures or an altered level of consciousness.

Specifics to look for in the presentation

  1. History of Hypertension
  2. Clinical presentation includes
    1. Visual loss
    2. Altered level of consiousness
    3. Seizures

Investigations

  • MRI

6.Pituitary Apoplexy

In Pituitary Apoplexy there is an acure infarct, or haemorrhage of the pituitary gland usually on the background of a pre-existing pituitary tumour. Precipitating factors can include pregnancy and anticoagulation.

Specifics to look for in the presentation

  1. Sudden headache usually behind the eyes.
  2. Clinical presentation includes
    1. Visual symptoms
      1. Decreased visual acuity
      2. Visual field defects
      3. Diplopia,
      4. Ptosis,
      5. Later eye deviation and mydriasis.
    2. Altered level of consiousness
    3. Seizures

Investigations

  • MRI

  • CT scan as the initial scan may be eaiser to obtain

7.Eclampsia and Pre-eclampsia

It is an uncommon cause of sudden severe headache, but patients may present with headaches. They may also present with scotomas and cortical blindness.

Specifics to look for in the presentation

  1. Pregnancy or first 12 weeks postpartum.
  2. Clinical presentation includes
    1. SBP > 140 mm Hg or DBP > 90 mm Hg
    2. Visual disturbance
    3. Seizures
    4. Proteinuria
    5. Hyper-reflexia
    6. Abdominal Pain

Investigations

  • Labs and Urine

  • MRI

8.Spontaneous Intracranial Hypotension

Patients can present with a sudden or gradual headache. It can be generalised or focal. It is usually postural and is relieved by lying down. It can be exacerbated by coughing or head movement. It is caused by a CSF leak that is either congenital or traumatic and results in a tear in the dura. This leak results in the brain ‘sagging’ in the cranial vault and causing traction on sensory nerve fibres.

Specifics to look for in the presentation

  1. Clinical presentation
    1. Postural headache is most common
    2. Diplopia and blurred vision
    3. Photophobia
    4. Neck stiffness
    5. Unsteady gait

Investigations

  • MRI
  • LP recording opening pressures

9.Giant Cell Arteritis

Patients with Giant Cell Artertiis(GCS) or Temporal Arteritis, are usually older (>50yo) present, in most cases, with temporal headache, although the headache can be in other areas or generalised. Symptoms may be acute in onset and last several days to weeks.

Specifics to look for in the presentation

  1. Headache
  2. Myalgia, fatigue and malaise
  3. Night sweats
  4. Jaw claudication
  5. Unexplained fever
  6. Pain over the scalp and/or over the temporal artery region.
  7. Eye signs
    1. Visual loss/blurred vision
    2. Visual field defects
    3. Diplopia
    4. Ptosis

Investigations

  • Labs
    • Raised ESR (usually > 50 mm/h- but can be normal in up to 20% of cases.
    • CRP rises before ESR and has greater sensitivity for GCA
    • Using both ESR and CRP provides a greater sensitivity.
    • A full Blood count will show an elevated platelet count in most patients.
  • Temporal Artery Biopsy
  • Color Duplex Ultrasound, may be an alternative moving forward.

10.Primary Exertional Headache

Exercise-induced headaches may vary from mild to severe headaches, triggered by intense physical exertion and usually associted with resistance training, cycling or running, but can be associated with other types of sports. The mean age of presentation is 24 years.

The headaches are usually diffuse, but can be localised. They are usually throbbing in nature and tend to last for less than 48 hours.

Older patients presenting with exercise-induced headaches, should raise suspicion for secondary causes of headache, which may include:

  • Intracranial structural abnormalities
    • Intracranial haemorrhage
    • Neoplasm
    • Space occupying Lesions such as cysts
    • Chiari Malformations (Congenital anatomic abnormalities of the craniocervical junction)
  • Intracranial Hypertension
  • Vascular Causes
    • Reversible Cerebral vasoconstriction Syndrome
    • Carotid/Vertebral(Cervical) artery dissection
  • Cardiac aetiology
    • Ischaemia
    • Hypertension
    • Takotsubo

Specifics to look for in the presentation

Diagnostic criteria (ICHD-3) requires the following criteria to be presents to make the diagnosis:

  1. At least 2 headache episodes
  2. Occur only during strenuous exercise
  3. Last for <48 hours
  4. No other ICHD-3 diagnosis would better explain the headache.

Investigations

Sudden onset severe headache during exertion, should first rule out subarachnoid haemorrhage and cerebral aneurysm.

  • CT brain and CTA (head and neck) or MRA .
  • Labs for other conditions including giant cell arteritis and cardiac ischaemia.

Listen to the PODCAST on sudden headache

What was the patient’s outcome?

The greatest concern with this patient was that this patient was not a headache sufferrer and although the headache occurred during exertion, it was persisting for too long. However the examination was normal, with no neurology and no evidence of infection and no symptoms consitent with Giant cell arteritis. The photophobia, was very mild and the patienrt was tolerating a well lit room and the temporal pain was also very mild.

All the labs were normal, including ESR and CRP. We were chasing a potential Giant Cell Arteritis here. Sometimes one or the other of these acute inflammatory markers may be raised, but not necessarily both. These were all normal, as were all the other bloods.

We perfomed a CT +A/V  because the patient was 48 yo and not a headahce sufferer and the headahce had persisted for so long. The scans were normal. We discussed this case with Neurology and their diagnosis was migraine. Although unsure of this as a diagnosis, there was very little else to do. They did not recommend temporal artery biopsy, or other scans.

References

  1. Edlow J et al. Case 18-2024: A 64 – year old Woman with the Worst Headache of Her Life. NEJM 2024;390:2108-18.
  2. Headache Classification Committee of the International Headache Society (IHS). The International Classification of Headache Disorders, 3rd edition. Cephalalgia 2018; 38: 1-211.
  3. Perry JJ, et al. Clinical decision rules to rule out subarachnoid hemorrhage for acute headache. JAMA 2013; 310: 1248-55.
  4. Linn FH, et al. Headache characteristics in subarachnoid haemorrhage and benign thunderclap headache. J Neurol Neurosurg Psychiatry 1998; 65: 791-3.
  5. Roberts T, et al. Thunderclap headache syndrome presenting to the emergency department: an international multicentre observational cohort study. Emerg Med J 2022; 39: 803-9.
  6. Perry JJ, et al. Clinical decision rules to rule out subarachnoid hemorrhage for acute headache. JAMA 2013; 310: 1248-55.
  7. Perry JJ, et al. High risk clinical characteristics for subarachnoid haemorrhage in patients with acute headache: prospective cohort study. BMJ 2010; 341: c5204.
  8. Dubosh NM, et al. Sensitivity of early brain computed tomography to exclude aneurysmal subarachnoid hemorrhage: a systematic review and meta-analysis. Stroke 2016; 47: 750-5.
  9. Ducros A. Reversible cerebral vasoconstriction syndrome. Lancet Neurol 2012;11: 906-17.
  10. Singhal AB, et al. Reversible cerebral vasoconstriction syndromes: analysis of 139 cases. Arch Neurol 2011; 68: 1005-12.
  11. Topcuoglu MA, et al. Hemorrhagic reversible cerebral vasoconstriction syndrome: features and mechanisms. Stroke 2016; 47: 1742-7.
  12. Cumurciuc R, et al. Headache as the only neurological sign of cerebral venous thrombosis: a series of 17 cases. J Neurol Neurosurg Psychiatry 2005; 76: 1084-7.
  13. von Babo M, De Marchis GM, Sarikaya H, et al. Differences and similarities between spontaneous dissections of the internal carotid artery and the vertebral artery. Stroke 2013; 44: 1537-42.
  14. de Bruijn SF, et al. Thunderclap headache as first symptom of cerebral venous sinus thrombosis. Lancet 1996; 348: 1623-5.
  15. Refai D, et al. Spontaneous isolated convexity subarachnoid hemorrhage: presentation, radiological findings, differential diagnosis, and clinical course. J Neurosurg 2008; 109:1034-41.
  16. Pascual J, et al. Cough, exertional, and sexual headaches: an analysis of 72 benign and symptomatic cases. Neurology 1996; 46:1520.
  17. Headache Classification Committee of the International Headache Society (IHS) The International Classification of Headache Disorders, 3rd edition. Cephalalgia 2018; 38:1.