CASE 18068 Published on 17.03.2023

A rare case of thunderclap headache



Case Type

Clinical Cases


Carlotta Ghiara, Giuseppe Simili

Department of Radiology, Hospital San Carlo, Milan, Italy


52 years, female

Area of Interest CNS, Emergency, Neuroradiology brain ; No Imaging Technique
Clinical History

A 52-year-old woman, with a history of sporadic constrictive holocranial headache with nausea, vomiting, and photophobia, presented to the hospital emergency unit for sudden onset of severe nuchal headache associated with vomiting.

Initially, neurologic objectivity was normal for focal signs, but showed nuchal pain when performing Lasegue bilaterally. The patient had no fever, and both laboratory tests and spinal tap were normal.

Imaging Findings

Non-contrast brain CT scan resulted negative, showing no pathological findings.

Subsequently, as symptoms worsened and left blurred hemi-syndromes appeared, CT angiography was performed. Images showed focal stenotic changes in the left posterior cerebral artery, anterior cerebral arteries, and middle cerebral arteries bilaterally. No evidence of ischemic lesions or hemorrhage.

A few days later, 3D-Time of Flight (TOF) MRI angiography confirmed the findings, demonstrating segmental and multifocal vasoconstriction in the P2-P3 tract of the left posterior cerebral artery, in the M2-M3 tract of the left middle cerebral artery, in an M2 sylvian branch on the right and the A2-A3 tract on the left.

Follow-up MRI at 3 months showed a normalisation of the caliber of the vessels.


Reversible cerebral vasoconstriction syndrome (RCVS) causes multifocal arterial stenosis and dilatation. Call–Fleming, "thunderclap" headaches with reversible vasospasm, benign CNS angiopathy, postpartum cerebral angiopathy, migrainous vasospasm, migraine angiitis, and drug-induced cerebral arteritis are all RCVS disorders [2]. The mechanism of segmental vasoconstriction is unknown, but sympathetic overactivity, endothelial dysfunction, and oxidative stress may cause cerebral vascular tone changes [3]. The postpartum time, several vasoactive and other medicines, sexual activity, and many other disorders like pheochromocytoma and porphyria predispose [2].

Thunderclap headache, usually occipital but sometimes widespread, is the most common primary symptom. Headaches usually last a few hours and return several days or weeks later. The average age of onset is 42 years, and women are affected more than men [1]. Other symptoms may include nausea, vomiting, photophobia, confusion, and blurred vision. Localized nonaneurysmal subarachnoid hemorrhage and ischemic stroke or intracerebral hemorrhage, which may cause long-term neurological impairments, are the main complications. Imaging is essential to detect multifocal cerebral artery constriction, which usually resolves spontaneously within 3 months [4]. Imaging allows the radiologist to rule out alternative diagnoses and monitor complications like ischemic stroke and intracranial hemorrhage [2].

The first diagnostic images obtained in most emergency departments are non-contrast CT images for brain parenchyma, which in the case of RCVS may be normal. Thereafter CT angiography (CTA) and MR angiography (MRA) can be used to show multifocal segmental stenosis and rule out cerebral aneurysms or arterial dissection. With a sensitivity of 100%, cerebral catheter digital subtraction angiography (DSA) is regarded as the gold standard for demonstrating the characteristic "string of beads" pattern of alternating areas of arterial stenosis and dilation, particularly in distant arteries. Additional advantages of DSA include the ability to verify response and treatment using intra-arterial injections of therapeutic drugs. Vessel wall MRI (VW-MRI) can help distinguish RCVS, which has no or mild contrast enhancement of the affected arterial wall, from other causes of vascular narrowing like vasculitis, which has intense contrast enhancement, or intracranial atherosclerotic plaques, which have focal contrast enhancement [5].

Regarding treatment modalities, against vasospasm, channel blockers have been utilised in the management of RCVS. Endovascular treatment, such as direct intra-arterial infusion of vasodilator medications and intracranial angioplasty, may be beneficial for patients with refractory cerebral vasoconstriction [4].

In most cases, the prognosis for RCVS is positive, as clinical and angiographic abnormalities typically resolve within a few days to weeks and it depends on the development of stroke or haemorrhage, with probable neurologic impairments resulting in persistent disabilities or even death [4].

Written informed patient consent for publication has been obtained.

Learning points:

  • RCVS is a transient cerebral vascular tone dysregulation that causes multifocal arterial constriction and dilation.
  • The main clinical manifestation is intense recurrent thunder headaches lasting one to three weeks. The gender most affected is female.
  • RCVS Imaging shows either vascular constrictions or complications related to them, such as convexity non-aneurysmal subarachnoid haemorrhage and ischemic lesions.
Differential Diagnosis List
Reversible cerebral vasoconstriction syndrome (RCVS)
Aneurysmal subarachnoid haemorrhage (SAH) and related vasospasm
Primary angiitis of the central nervous system (PACNS)
Arterial dissection
Posterior Reversible Encephalopathy Syndrome (PRES)
Final Diagnosis
Reversible cerebral vasoconstriction syndrome (RCVS)
Case information
DOI: 10.35100/eurorad/case.18068
ISSN: 1563-4086