Unusual Stroke Presentations

Unusual Stroke Presentations

By Jeffrey Conley MD
EM Resident Physician, Albany Medical Center

Edited by Alex Koyfman MD and Stephen Alerhand MD

Featured on #FOAMED REVIEW 37TH EDITION – Thank you to Michael Macias from emCurious (@EMedCurious) for the shout out!

Below is a large review of the main points to consider for the various presentations of stroke in the ED.

Subarachnoid Hemorrhage (SAH)

– Approximately 1% of patients presenting to ED with headache
– ~75% are result of ruptured aneurysm
– 30,000 patients annually in the U.S.
– ~20% occur with no known precipitating cause.
– Increased risk: aneurysm in 1st degree relative, polycystic kidney disease

Typical Symptoms:

– “Thunderclap headache” = worst headache of life with maximal intensity within min of onset
– Nausea, vomiting, altered mental status (AMS), photophobia, or focal neurological complaint.
– ~20% of cases occur after activities that increase blood pressure (sexual intercourse, exercise, or bowel movement)

Unusual presentations

– 8-20% of patients misdiagnosed on initial visit

1) The sentinel bleed
– Less severe than classic “thunderclap”
– Symptoms may be transient
– Suspect if headache is different from patient’s usual headache or occurs in a patient without history of headaches

2) Patient with neurologic findings and hemodynamic instability
– Cushing’s triad – bradycardia, hypertension, and irregular respirations
– Result of increased intracranial pressure (ICP) and insufficient brain perfusion
– Treatment is neurosurgical intervention and ICP lowering measures (more detailed info: http://www.emdocs.net/icp-management-update/ )
– Mannitol, elevate head of bed, sedation
– Blood pressure control (debated but still recommended)

Diagnosis by CT


Intraparenchymal bleed

  • CT scan has a sensitivity of 98% within the first 12 hours of onset and 93% within 24 hours. Sensitivity decreases to approximately 80% at 72 hours and 50% at 1 week.
  • Head CT’s obtained within 6 hours of symptom onset have been shown to have 100% sensitivity and 100% NPV. (Perry et al.)

Fundoscopic Exam

Lumbar Puncture

– Positive result will yield a mean Red Blood Cell (RBC) count of 300,000 per tube (# is controversial).
– For a negative result, expect Tube 4 < 500 with clearance > 70% from tube 1 to tube 4
– Also look for xanthochromia
– The presence of a yellow hue results from red blood cell breakdown and release of bilirubin into the cerebral spinal fluid, indicating ICH


Ischemic stroke

There is a seemingly endless number of unusual clinical presentations that can result from ischemic stroke, many of which are only discovered after advanced imaging. Key history elements of stroke include the presence of risk factors for stroke and a sudden onset of symptoms.

Risk factors for ischemic stroke:
advanced age, smoking, hypertension, and diabetes

The freebee:

  • Hemiparesis / sensory deficits, aphasia, AMS, unilateral neglect. Often large vessel infarctions which compromise blood flow to a large cerebral territory.


Diagnosis via CT
diagnosis via CT
Naccarato et al. Lipids in Health and Disease 2010



Presentations can be subtle and may involve any of the following:

  • Brainstem involvement can result in:
    • Eyelid drooping, oculomotor weakness, altered pupillary light reflex.
    • Facial muscle weakness
    • Loss of gag reflex or difficulty swallowing
    • Altered sense of taste, smell, vision, or hearing
    • Hemodynamic or respiratory instability
  • Cerebral involvement can result in:
    • Altered mental status / confusion / disorganized thinking
    • Loss of impulse control / loss of insight
    • Visual field deficits
    • Aphasia, dysarthria
    • Apraxia
    • Memory deficits
    • Hemineglect
  • Cerebellar involvement can result in:
    • Loss of coordination
    • Altered gait
    • Vertigo/disequilibrium, nystagmus


Uncommon stroke presentations

Pure sensory deficit
  • A patient reporting sudden hemi-sensory loss is concerning for thalamic lacunar infarction
    • Can also involve the afferent tracts to the midbrain.
    • Lacunar infarcts are ischemic events that result from occlusion of the deep penetrating arteries, small vessels branching off of the major constituents of the cerebrovascular system.
      • Often seen on MRI as chronic infarctions due to surrounding edema.
    • Typically very small lesions, often patient with negative CT results.
Pure visual loss
  • Isolated visuals loss can occur due to infarction of the occipital cortex.
    • May also experience vision loss due to infarction of territories containing visual pathways from the optic nerve to the optic radiations.
      • This includes the frontal lobes, thalamus, temporal lobes, and a large portion of the posterior cerebral cortex.
    • Patients will have normal optic discs and physiological pupillary light reflexes.
      • Patients may be unaware of visual deficits: known as visual anosognosia.
Acute onset confusion, agitation, and delirium
  • Involve lesions of the limbic system of the orbitofrontal and temporal lobes.
  • Difficult to identify due to limited exam:
    • Identify as acute cerebrovascular event with history of acute onset and presence of focal neurological deficits, often visual field loss or neglect.
Dizzy (vertigo) / dysmetria
  • Posterior circulation defect resulting in cerebellar infarction.
    • Must consider in anyone with abnormal sense of motion. Especially if patient denies any history of vertigo.
  • PE: HINTS testing
    • Head impulse testing (eyes lose fixed point during rotation)
    • Observation for nystagmus (direction changing or vertical)
    • Test for skew deviation (covered eye deviates from fixed point when covered)
  • Must evaluate with MRI
    • CT is insensitive for cerebellar or brainstem infarction.
      • MRI:DWI sensitivity for ischemic stroke = 0.99
      • CT sensitivity for ischemic stroke = 0.39
Locked-in syndrome
  • Patient is aware but cannot move or communicate verbally
  • Total paralysis except for the eyes
  • Results from occlusion of the basilar artery, resulting in infarction of the pons.
    • No vocal cord paralysis, though unable to communicate due to loss of voluntary control of diaphragm.
Stroke mimics:
  • Todd’s paralysis
    • Focal neurologic deficits presenting after seizure activity
    • Resolves in minutes to hours (most in < 48 hours)
  • Toxicology
  • Complex migraine
  • Hypoglycemia
  • Bell’s Palsy
  • Conversion disorder



References / Further reading:

– Brazzelli M, Sandercock PAG, Chappell FM, Celani MG, Righetti E, Arestis N, Wardlaw JM, Deeks JJ (2009) Magnetic resonance imaging versus computed tomography for detection of acute vascular lesions in patients presenting with stroke symptoms. Cochrane review. The Cochrane Collaboration The Cochrane Library. 2009, Issue 4

– Czuczman AD, Thomas LE, Boulanger AB, Peak DA, Senecal EL, Brown DF, Marill KA. (2013) Interpreting red blood cells in lumbar puncture: distinguishing true subarachnoid hemorrhage from traumatic tap. Academic Emergency Medicine. 2013 March: 247-56.

– Dennis R. Groothuis MD, Dr. Gary W. Duncan MD* and C. Miller Fisher MD. The human thalamocortical sensory path in the internal capsule: Evidence from a small capsular hemorrhage causing a pure sensory stroke. Annals of Neurology. Volume 2, Issue 4, pages 328–331, October 1977.

– Gipe B, McFarland D (1994): Subarachnoid hemorrhage: An unusual presentation of shock. Annals of Emergency Medicine. July 1994:26;85-89.

– JONATHAN A. EDLOW, M.D., AND LOUIS R. CAPLAN, M.D (2000). The New England Journal of Medicine. Avoiding Pitfalls in the Diagnosis of Subarachnoid Hemorrhage. January 6, 2000. Volume 342 Number 1 · Pg 29-36

– Jorge C. Kattah, Arun V. Talkad, David Z. Wang, Yu-Hsiang Hsieh, and David E. Newman-Toker. HINTS to Diagnose Stroke in the Acute Vestibular Syndrome: Three-Step Bedside Oculomotor Examination More Sensitive Than Early MRI Diffusion-Weighted Imaging. Stroke. 2009;40:3504-3510

– Julie Gorchynski, Jennifer Oman, and Todd Newton (2007). Interpretation of Traumatic Lumbar Punctures in the Setting of Possible Subarachnoid Hemorrhage: Who Can Be Safely Discharged? Journal of Emergency Medicine. Feb 2007.

– Perry JJ et al. Sensitivity of computed tomography performed within six hours of onset of headache for diagnosis of subarachnoid haemorrhage: Prospective cohort study. BMJ 2011 Jul 18; 343:d4277.

– Tintinalli’s Emergency Medicine 7th ed. Neurology. Section 14: Chapter 160-161; 1118-1135.


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