Classical stroke syndromes

There is a list of "classical" stroke syndromes arranged by arterial territory, which one needs to commit to memory. This list includes dominant and non-dominant MCA infarction, medial and lateral medullary syndromes,  anterior and posterior cerebral artery syndromes and the basilar artery syndrome. Thus far, CICM have not expected their exam candidates to make this sort of diagnosis in the written papers, perhaps with the exception of Question 10.1 from the second paper of 2013 and Question 27 from the first paper of 2019, both of which asked about lateral medullary syndrome.

The Internet Stroke Centre used to be an excellent summary of stroke syndromes, and was the main source for this summary. It even had references to the studies which describe each specific stroke syndrome. Unfortunately, this site has gone down (presumably because like other free online resources this one must have been powered by either a time-limited government grant or the energy of a single sleepless enthusiast). Much of their content has been recovered using archive.org and is preserved in the entries below. For those who want a peer-reviewed reference for their exam preparation, hopefully this link to Balami et al (2013) will have somewhat better longevity, it being an academic publication. 

Anterior cerebral artery

Anterior cerebral artery syndrome

  • Contralateral hemiparesis of lower limbs
  • Contralateral sensory loss of lower limbs
  • Anosmia- olfactory bulb is infarcted
  • These are fairly rare, as the anterior communicating artery allows collateral blood flow 

Alien hand syndrome (anterior corpus callosum or anterior cingulate)

  • Independent motor activity of the left limb (usually, relatively complex activity, some apparently goal-oriented, and all of it entirely involuntary)
  • This happens from infarction of A4 and A5, smallest branches of the ACA which supply the corpus callosum

Middle cerebral artery syndromes

Whole of the dominant MCA: Gerstmann syndrome

  • Agraphia
  • Acalculia
  • Finger agnosia
  • Right-left disorentation
  • Contralateral weakness
  • Contralateral sensory loss
  • Contralateral hemineglect
  • Contralateral homonymous hemianopia
  • Global aphasia (receptive and expressive)
  • See Gerstmann (1924), except you can't because it's not available anywhere. So, instead, see Rusconi (2018)

Inferior division of dominant MCA

  • Contralateral homonymous hemianopia or upper quadrant anopsia
  • Receptive aphasia (as it takes out Wernicke's area)

Superior division of dominant MCA

  • Contralateral weakness (mostly face and arm, not so much leg and foot)
  • Mainly the lower half of the contralateral face is affected
  • Contralateral sensory loss (including the face)
  • Contralateral hemineglect
  • Expressive aphasia (as it takes ot Broca's area)

Whole non-dominant MCA 

  • Contralateral weakness
  • Contralateral sensory loss
  • Contralateral hemineglect
  • Contralateral homonymous hemianopia
  • Constructional apraxia (where you lose the ability to reproduce drawing or 3D shapes)
  • Spatial disorientation

Inferior division of non-dominant MCA

  • Contralateral homonymous hemianopia or upper quadrant anopsia
  • Constructional apraxia

Superior division of non-dominant MCA

  • Contralateral weakness (mostly face and arm, not so much leg and foot)
  • Mainly the lower half of the contralateral face is affected
  • Contralateral sensory loss (including the face)
  • Contralateral hemineglect

Ataxic hemiparesis

  • small penetrating arteries of the MCA, or the basilar artery, affecting the posterior limb of external capsule and the pons (basis pontis)
  • Contralateral weakness (usually more in the leg then the arm)
  • Contralateral ataxia
  • No facial involvement

Posterior cerebral artery

Callosal branches: dominant occipital plus splenium of corpus collosum

  • Alexia (reading incomprehension) is the result of damage to the splenium, the thickest and most posterior portion of the corpus callosum. Weirdly, the sufferer remains able to spell words and even writing sentences, but is unable to understand them.
  • Contralateral homonymous hemianopia
  • This seems to be occasionally referred to as "alexia without agraphia"

Midbrain tegmentum, the "floor" of the midbrain (Claude syndrome)

  • Contralateral arm and leg ataxia with tremor (because the superior cerebellar peduncles are infarcted)
  • Ipsilateral oculomotor nerve palsy

Ventromedial midbrain (Weber syndrome)- penetrating midbrain branches of the PCA

Thalamic pain syndrome (Dejerine-Roussy syndrome) - ventroposterolateral thalamus

  • Contralateral hemisensory loss
  • Contralateral pain: neuropathic, usually burning it character, with hyperalgesia and allodynia
  • Theoretically, any lesion that interrupts the spinothalamic tract can cause this, at any point in its path

Unilateral occipital lobe  

  • Homonymous hemianopia
  • Depending on how much or how little of the lobe is taken out, there may be other weird visual disturbances, like colour anomia.

Bilateral occipital lobes - bilateral PCA, or top of the basilar artery (Anton syndrome)

  • Bilateral visual loss (cortical blindness)
  • Anosognosia, the unawareness or denial of blindness (this is the part which makes it Anton syndrome; the patient often confabulates to compensate for the lost visual information, refuses to admit that they are blind, complains that the room is dark because somebody has turned out the lights, etc)

Bilateral parietal and occipital lobes (Balint syndrome)

  • Loss of voluntary eye movements (but reflex movements are preserved)
  • Optic ataxia (poor coordination of eye motor movement)
  • Asimultagnosia (the inability to understand visual objects)
  • This disorder requires both posterior cerebral arteries to be occluded, which is a fairly uncommon event

Basilar artery

In order of higher to lower, moving down the brainstem:

Weber syndrome (occlusion of one of the paramedian branches of the basilar artery)

  • Ipsilateral oculomotor nerve palsy 
  • Contralateral hemiplegia

Paramedian midbrain syndrome (Benedikt syndrome) - infarction of PCA branches to oculomotor nerve fascicles and the red nucleus:

  • Ipsilateral oculomotor nerve palsy
  • Contralateral ataxia
  • Contralateral intention tremor

Inferior medial pontine syndrome (Foville syndrome)

  • Unilateral lesion in the dorsal pontine tegmentum in the caudal third of the pons
  • Results from the infarction of paramedian branches or the short circumferential branches of the basilar artery
  • Contralateral weakness
  • Ipsilateral facial weakness
  • Ipsilateral lateral gaze palsy (CN VI palsy)

Ventral pontine syndrome (Raymond syndrome)

  • Ipsilateral lateral gaze palsy (CN VI palsy)
  • Contralateral weakness
  • Apparently Millard-Gubler syndrome is an alternative name for this thing (when the facial nerve is also involved)

Medial medullary syndrome (Dejerine syndrome)

  • Alternative vascular culprits include the vertebral artery or the anterior spinal artery
  • Contralateral weakness 
  • Contralateral sensory loss of vibration and proprioception 
  • Ipsilateral tongue weakness, atrophy and fasciculations (hypoglossal nerve lesion)

Locked-in syndrome

  • Bilateral whole-body weakness
  • Bilateral facial weakness
  • Lateral gaze weakness
  • Dysarthria
  • Essentially, this syndrome (the infarction of the whole ventral pons) results in paralysis of all movements except vertical gaze and eyelid opening.

Anterior inferior cerebellar artery (AICA)

Lateral pontine syndrome (Marie-Foix Syndrome)

  • Ipsilateral cerebellar ataxia (arm and leg)
  • Ipsilateral facial weakness 
  • Ipsilateral hearing loss, vertigo and nystagmus (because CN VIII is taken out)
  • Theoretically, the ipsilateral cold caloric reflex will be absent
  • Contralateral weakness (corticospinal tract)
  • Contralateral pain and temperature loss (spinothalmic tract)
  • This could be the AICA, or it could be long circumferential branches from the basilar artery

Posterior inferior cerebellar artery (PICA)

Lateral medullary syndrome (Wallenberg Syndrome)

  • On the side of the lesion:
    • Facial sensory loss
    • Nystagmus
    • Horner's syndrome
    • Loss of gag reflex
    • Ipsilateral ataxia with a tendency to fall to the ipsilateral side
  • On the contralateral side:
    • Pain and temperature sensory loss in the extremities
  • Generally:
    • Vertigo
    • Nausea
    • Dysphagia

References

Balami, J. S., R. L. Chen, and A. M. Buchan. "Stroke syndromes and clinical management." QJM: An International Journal of Medicine 106.7 (2013): 607-615. (Readers should be grateful to Pri Patel for submitting this reference, and for drawing attention to the death of the Internet Stroke Centre)

Qureshi, Adnan I., et al. "Spontaneous intracerebral hemorrhage." New England Journal of Medicine 344.19 (2001): 1450-1460.

Caplan, L. R. "Basic Pathology, Anatomy, and Pathophysiology of Stroke." Caplan’s Stroke A Clinical Approach (2009): 23-4.

Gerstmann, Josef. "Fingeragnosie-Eine umschriebene Storung der Orientierung am eigenen Korper." Wiener Klinische Wochenschrift 37 (1924): 1010-1012.

Rusconi, Elena. "Gerstmann syndrome: historic and current perspectives." Handbook of clinical neurology 151 (2018): 395-411.

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