Characteristic feature(s) | Suspected etiology | Choice of initial diagnostic imaging test(s) |
Age >60 years Baseline cognitive impairment | CAA | MRI brain with T2*-weighted SWI or GRE sequences |
Recurrent thunderclap headache (>2 within 1 week) Exposure to vasoactive substance | RCVS | CTA or MRA of head MRI brain |
Risk factor for venous thrombosis* Head CT features suggestive of venous thrombosis (eg, hyperdense venous sinus; venous infarction) | CVT | CTV or MRV of head MRI brain |
New heart murmur Systemic/cutaneous evidence of embolism | Mycotic aneurysm | MRI brain with contrast or cerebral DSA |
Clinical history of active cancer Clinical history of new persistent headaches Head CT features suggestive of tumor (eg, vasogenic edema) | Brain tumor | MRI brain with contrast |
Headache prior to neurologic deficits Clinical history of connective tissue disorder | Intracranial dissection | CTA of head or cerebral DSA |
Head CT features suggestive of AVM (calcification or hypodense flow voids adjacent to SAH) | AVM | Cerebral DSA |
History of minor/occult trauma may be elicited Evidence of extracranial bleeding or systemic injuries | Occult trauma | MRI brain |
Clinical history of new persistent headaches Progressive cognitive or other neurologic impairments | Vasculitis | MRI brain with contrast Cerebral DSA Brain and meningeal biopsy |
SAH: subarachnoid hemorrhage; CAA: cerebral amyloid angiopathy; MRI: magnetic resonance imaging; SWI: susceptibility-weighted imaging; GRE: gradient recall echo imaging; RCVS: reversible cerebral vasoconstriction syndrome; CTA: computed tomographic angiography; MRA: magnetic resonance angiography; CT: computed tomography; CVT: cerebral venous thrombosis; CTV: computed tomography venography; MRV: magnetic resonance venography; DSA: digital subtraction angiography; AVM: arteriovenous malformation.
* Refer to UpToDate topic on the causes of venous thrombosis.Do you want to add Medilib to your home screen?