How to diagnose a cerebrovascular accident (CVA) with a physical examination?

Diagnosing Cerebrovascular Accident Through Physical Examination

A thorough neurological examination is the cornerstone of diagnosing a cerebrovascular accident (CVA) when imaging is unavailable, focusing on systematic assessment of cranial nerves, motor function, sensory function, coordination, and reflexes to identify focal neurological deficits characteristic of stroke.

Level of Consciousness Assessment

• Begin by assessing the patient's level of consciousness using the Glasgow Coma Scale (GCS), evaluating eye opening, verbal response, and motor response 1
• Evaluate orientation to person, place, and time to detect altered mental status which may indicate a large vessel stroke 1
• Test the patient's ability to follow simple commands such as opening/closing eyes and grip/release hand 1

Cranial Nerve Examination

• Systematically test all 12 cranial nerves with particular attention to:
  • CN II: Check visual acuity and visual fields using confrontation testing to detect hemianopia 1
  • CN III, IV, VI: Evaluate pupillary size, reactivity, and eye movements for asymmetry 1
  • CN V: Test facial sensation in all three divisions and jaw strength 1
  • CN VII: Assess facial symmetry and movement, looking for facial droop (a classic sign of CVA) 1
  • CN IX, X: Evaluate swallowing and palatal elevation for asymmetry 1
  • CN XII: Check tongue protrusion for deviation, which may indicate hypoglossal nerve involvement 1

Motor Function Assessment

• Have patients extend arms at 90° (seated) or 45° (supine) for 10 seconds to detect pronator drift, a sensitive sign of subtle motor weakness 1
• Ask patients to raise legs 30° and hold for 5 seconds to assess lower extremity strength 1
• Assess strength in major muscle groups using the Medical Research Council 0-5 scale, comparing symmetry between sides 1
• Evaluate muscle tone through passive range of motion to detect spasticity or flaccidity 1

Sensory Function Assessment

• Test various sensory modalities including:
  • Light touch
  • Pain/temperature sensation using pinprick
  • Vibration using a tuning fork
  • Proprioception (joint position sense) 1
• Compare symmetry between sides, as unilateral sensory loss is highly suggestive of CVA 1

Coordination and Cerebellar Function

• Test finger-to-nose and heel-to-shin movements to detect ataxia, which may indicate cerebellar stroke 1
• Assess rapid alternating movements (dysdiadochokinesia) which may be impaired in cerebellar strokes 1
• Evaluate gait and balance if patient is able to stand and walk, looking for ataxia or hemiparetic gait 1

Reflex Testing

• Check deep tendon reflexes (biceps, triceps, brachioradialis, patellar, Achilles) for asymmetry or hyperreflexia 1
• Test for pathological reflexes including Babinski sign, which may be present in upper motor neuron lesions 1

Standardized Assessment Tools

• Use the National Institutes of Health Stroke Scale (NIHSS) for a standardized assessment of stroke severity 2
• The NIHSS provides a quantitative measure of stroke-related neurologic deficit and helps in monitoring for clinical changes 2

Special Examination Techniques

• For patients with suspected cerebellar stroke, perform the HINTS examination (Head-Impulse, Nystagmus, Test of Skew), which is more sensitive for cerebellar stroke than early MRI 2
• In patients with altered consciousness, document the GCS score to track neurological status 1

Pattern Recognition for CVA Diagnosis

• Look for the following classic patterns suggestive of CVA:
  • Hemiparesis (weakness on one side of the body)
  • Hemianesthesia (sensory loss on one side)
  • Hemineglect (neglect of one side of the body or space)
  • Aphasia (language impairment)
  • Dysarthria (slurred speech)
  • Visual field defects 2

Common Pitfalls to Avoid

• Avoid incomplete motor testing - always assess both sides for comparison 1
• Be aware of stroke mimics such as hypoglycemia, seizures, migraines, and Creutzfeldt-Jakob disease 3
• Check blood glucose levels to rule out hypoglycemia, which can mimic stroke symptoms 2
• Remember that CVA symptoms can be subtle, especially in posterior circulation strokes 2

Timing Considerations

• Document the time of symptom onset or "last known well" time, as this is critical for treatment decisions 2
• Perform serial examinations to detect neurological deterioration or improvement 1

By systematically applying this physical examination approach, clinicians can effectively diagnose cerebrovascular accidents even without immediate access to neuroimaging, allowing for timely intervention and potentially improved outcomes.