What is the appropriate workup for a patient presenting with headache, limb weakness, and blurred vision?

Immediate CT Head Without Contrast, Followed by MRI and Vascular Imaging

This patient requires emergent CT head without IV contrast as the initial imaging study, followed by MRI brain and CTA head and neck to evaluate for acute stroke, intracranial hemorrhage, cerebral venous sinus thrombosis, or vascular dissection 1.

Initial Workup Algorithm

Immediate Actions

• Obtain vital signs immediately, particularly blood pressure—severe hypertension (>200/130 mmHg) can cause hypertensive brainstem encephalopathy presenting with these exact symptoms 2
• Perform fundoscopic examination to assess for papilledema, hemorrhages, or exudates, which can identify increased intracranial pressure or hypertensive emergency 2, 3
• Test visual fields formally—unilateral or bilateral deficits may indicate posterior circulation stroke, mass lesion, or venous thrombosis 4
• Assess limb weakness pattern: unilateral suggests stroke/dissection; bilateral suggests brainstem pathology or venous thrombosis

Imaging Sequence

First: CT Head Without Contrast (usually appropriate) 1

• Rapidly excludes hemorrhage (subarachnoid, intraparenchymal)
• Identifies mass effect, herniation
• Can detect large acute infarcts
• Essential before any intervention

Second: MRI Brain Without IV Contrast (usually appropriate) 1

• Superior for detecting acute ischemic stroke, especially in posterior circulation
• Identifies brainstem lesions (hypertensive encephalopathy shows asymmetric hyperintensities) 2
• Detects venous infarction from cerebral venous sinus thrombosis
• More sensitive than CT for small infarcts

Third: CTA Head and Neck (usually appropriate) 1

• Rapidly acquired vascular imaging guides intervention decisions
• Identifies large vessel occlusion requiring thrombectomy
• Detects aneurysms (IC-PC aneurysms can cause oculomotor nerve dysfunction with blurred vision and headache before rupture) 5
• Evaluates for arterial dissection

Critical Diagnostic Considerations

High-Risk Scenarios Requiring Urgent Recognition

Cerebral Venous Sinus Thrombosis (CVST)

• Particularly in postpartum women or those on oral contraceptives 6
• Presents with headache, focal deficits, altered mental status
• MRI with venography is diagnostic when suspected 1
• Fatal in 3-15% of cases if missed 6

Aneurysmal Rupture or Expansion

• Blurred vision with eye discomfort during headache may indicate early oculomotor nerve dysfunction from IC-PC aneurysm expansion 5
• If CT shows subarachnoid hemorrhage, proceed directly to catheter angiography (>98% sensitivity/specificity) 7

Hypertensive Emergency

• Blood pressure >200/130 mmHg with end-organ damage
• Brainstem encephalopathy can present with minimal neurological deficits despite striking MRI findings 2
• Requires immediate IV antihypertensive therapy (calcium channel blockers)

Acute Ischemic Stroke

• Time-critical: imaging defines infarct extent and guides thrombectomy decisions 1
• Both <24 hours and >24 hours require same initial imaging approach

Common Pitfalls to Avoid

• Do not dismiss symptoms as functional/conversion disorder without completing full imaging workup—CVST was misdiagnosed as functional neurological disorder in a postpartum woman with catastrophic delay 6
• Do not skip fundoscopic examination—emergency providers perform ophthalmoscopy in only 14% of headache patients, missing critical findings 3
• Do not assume migraine in patients with new-onset symptoms or risk factors (postpartum, oral contraceptives, severe hypertension)
• Do not delay vascular imaging—CTA should be obtained rapidly, not as a delayed add-on 1

Additional Testing Based on Initial Findings

If initial imaging is negative but clinical suspicion remains high:

• Lumbar puncture to assess opening pressure (elevated in CVST, hypertensive emergency) and exclude infection/hemorrhage 2
• MR venography if CVST suspected despite negative initial studies 1
• Catheter angiography if SAH present but CTA negative (identifies aneurysms in 13% of CTA-negative cases) 7

The key is rapid, parallel processing: obtain CT immediately while preparing for MRI and CTA, rather than sequential testing that delays diagnosis of time-sensitive conditions like stroke or aneurysmal rupture.