72yo male, acute right Hemiparesis and right facial droop

Hemorrhage - headache, altered mental status, seizures, nausea and vomiting, and/or marked hypertension - otherwise the site of the lesion is similar stroke

Stroke Mimics (Based on hemiparesis symptoms)

Stroke Lesion Localization

Endocrine: hypoglycemia, hypothyroidism, adrenal insufficiency (but endocrine causes can also cause myopathy)

Infection or sepsis

Fluids & electrolytes: Dehydration, K, Ca, Mg, or PO4 imbalance

Rheumatological: e.g. RA, SLE.

Cardiac: acute coronary syn, anemia, presyncope

General neurology: hemiplegic migraine, postictal paralysis after a seizure

Drugs & toxins: CO poisoning, meds

Psychiatric: e.g. conversion disorder.

Contralateral Hemiparesis

Ipsilateral Full Face

Lateral Gaze Weakness (CN VI)

Contralateral Face Lower Half Weakness

Sparing the face

Ventral Pontine Syndrome (Raymond) – Paramedian br.

Ventral Pontine Syndrome (Millard-Gubler) basilar a.: short circumferential br / paramedian br.

Contralateral loss of pain and temp sensation

Lateral pontine syndrome (basilar – long circumferential br / AICA)

  • Ipsilateral limb ataxia
  • CN VIII lesion – ipsilateral hearing loss, vertigo, and nystagmus

Ipsilateral Oculomotor nerve palsy: drooping eyelid, fixed wide pupil pointing down and out -> diplopia

Weber Syndrome (midbrain infarct – paramedian branches of PCA / Basilar bifurcation perforating arteries)

Lateral Gaze Weakness (CN VI) / Ipsilateral ataxia / Contralateral loss of proprioception and vibration (medial lemniscus)

Inferior medial pontine syndrome (Foville) Paramedian br / Short circumferential a. of basilar a.

Sensory loss of contralateral face, arm, and leg

Ataxia of contralateral extremities

Lacunar Infarct

Middle Cerebral Artery Infarct

  • Speech impairment (Broca’s, Wernicke’s or Global aphasia
  • Perceptual deficits
  • Visual Disorder (Deviation conjuguee – gaze toward size of lesion; contralateral homonymous hemianopia)
    *may be expressive in anterior MCA territory infarction (Broca), receptive in posterior MCA stroke (Wernicke), or global with extensive infarction

Diagnositic Tools

CT scan can near-perfectly detect haemorrhage but not small,recent ischaemia

Diffuse Weighted MRI (DWI-MRI) detects acute brain ischemia in about 90% & 33% of TIA

Gradient-echo T2-weighted susceptibility MRI is as sensitive as CT for acute haemorrhage and more sensitive for previous haemorrhage

Total anterior circulation syndrome (All 3) / Partial Anterior Circulation syndrome (2/3)

  • Contralateral motor or sensory deficit
  • Homonymous hemianopia
  • Higher cortical dysfunction

Face Arm and Speech Test (FAST) = Recognition of Stroke in the Emergency Room (ROSIER) score

Supratentorial hemorrhage (85%)

  • contralateral sensory or motor deficits
  • aphasia
  • neglect
  • gaze deviation
  • hemianopia.

Infratentorial hemorrhages

  • signs of brainstem dysfunction
  • cranial nerve abnormalities
  • ataxia
  • nystagmus
  • dysmetria