VASCULAR DISTRIBUTIONS AND STROKE SYNDROMES : APPROACH TO THE PATIENT SUFFERING STROKE Christine Holmstedt, D.O. Assistant Professor of Neurology Medical Director of Clinical Stroke Services MUSC OBJECTIVES • Help develop a systematic approach to the patient suffering stroke • Recognize specific stroke syndromes based on clinical presentations and physical exam findings • Correlate syndrome to vascular distribution Sidenotes • These are the SICKEST patients in your ED • WE NEED YOUR HELP – Don’t leave the bedside – Concurrent medical issues • Get the right story – LAST KNOWN NORMAL – MEDICATIONS Question • You are called emergently to see a stroke patient in the ED, the first thing you assess on arrival is? INITIAL PATIENT SURVEY • ABC’s, ABC’, ABC’s, • Vital signs – – – – Blood pressure Pulse rate and rhythm Respiratory rate Saturations • General survey – Mental Status • Level of consciousness – Distress – Trauma SECONDARY SURVEY • Quick patient neurologic overview – Forced deviation – Plegia – Aphasic – Dysarthria • • • • Which hemisphere is affected Anterior verses posterior Cortical verses subcortical Large vessel verses small vessel NIHSS • Standardized exam designed to improve communication between health care providers • Measure the level of impairment caused by a stroke. • Scores should reflect what the patient does, not what the clinician thinks the patient can do • Main use in clinical medicine is during the assessment of whether or not the degree of disability caused by a given stroke merits treatment with tPA • Useful for data collection • Not a neurologic exam Physical Exam • Complete physical exam • Neurologic exam Question? • While doing the NIHSS, do you include a patient’s previous neurologic disability? Anterior circulation • Internal Carotid arteries • Anterior cerebral arteries • Middle cerebral arteries Internal Carotid Artery • Internal carotid artery – Branch of the common carotid • Bifurcates in the neck – Divides into • ACA • MCA • Posterior communicating artery – Circle of Willis Internal Carotid Artery • • • • • • • Cervical C1 Petrous C2 Lacerum C3 Cavernous C4 Clinoid C5 Ophthalmic C6 Communicating C7 Clinical Syndromes • Variable depending on territorial stroke – – – – MCA ACA MCA/ACA MCA/ACA/Occipital lobe • Depends on hemisphere involved • Depends on dominance of brain • Depends on acuity of occlusion – Younger more acute occlusion typically more devastating – More chronic occlusion may by asymptomatic Clinical Syndrome • Dominant hemisphere – – – – – – Aphasia Contralateral hemiplegia/paresis face, arm and leg Visual field cut Sensory loss Gaze preference Dysarthria • Non-Dominant hemisphere – – – – – – – – Contralateral hemiplegia/paresis face, arm and leg Visual field cut Sensory loss Gaze preference Dysarthria Neglect Personality changes Apraxia Anterior Cerebral Arteries • Surface branches supply cortex and white matter of : – inferior frontal lobe – medial surface of the frontal and parietal lobes – anterior corpus callosum • Penetrating branches supply: – – – – – deeper cerebrum diencephalon limbic structures head of caudate anterior limb of internal capsule Clinical Syndrome • Left ACA – Right leg weakness – Right leg sensory loss – Grasp reflex – Frontal lobe behavior abnormalities – Motor aphasia – Larger infarcts can cause hemiplegia Clinical Syndrome • Right ACA – Left leg weakness – Left leg sensory loss – Grasp reflex – Frontal lobe behavior abnormalities – Left hemi-neglect Middle Cerebral Arteries • Surface branches supply – Cortex & white matter of hemispheric convexity • All four lobes. • Penetrating branches – Deep matter – Some diencephalic structures Middle Cerebral Arteries • Horizontal segment M1 • Lateral lenticulostriate vessels • Sylvian segment M2 • Cortical Segment M3 Middle Cerebral Arteries • Left MCA Stem M1 – Right hemiplegia/paresis – Right sensory loss – Right VF cut – Global aphasia – Left Gaze preference Middle Cerebral Arteries • Left anterior (superior) division – Right face, arm>leg weakness – Motor aphasia – Some right face and arm sensory loss Middle Cerebral Arteries • Left posterior (inferior) MCA – Fluent sensory aphasia – Right VF cut – Right face, arm and leg sensory loss – May appear confused or “crazy” Middle Cerebral Arteries • Right MCA Branch (M1) – Left hemiplegia/paresis – Left sensory loss – Left VF cut – Left hemi-neglect – Right gaze preference Middle Cerebral Arteries • Right anterior (superior) division – Left face, arm>leg weakness – Left hemi-neglect – Gaze preference Middle Cerebral Arteries • Right posterior (inferior) division – Left hemi-neglect – Left VF cut – Left sensory loss – Decreased voluntary movements – Left motor neglect (normal strength) Lacunar infarcts • Occlusion of one of the penetrating arteries that provides blood to the brain's deep structures • Lacunes are caused by occlusion of a single deep penetrating arteries that arises directly from the constituents of the Circle of Willis, cerebellar arteries, and basilar artery. • 37% putamen • 14% thalamus • 10% caudate • 16% pons • 10% posterior limb of the internal capsule Lacunar infarcts • Pure motor stroke/hemiparesis 33-50% – Posterior limb of the internal capsule, or the basis pontis • Weakness face, arm, or leg • May have dysarthria, dysphagia and transient sensory symptoms • Ataxic hemiparesis – Posterior limb of the internal capsule, basis pontis, and corona radiata • Weakness and clumsiness arm, or leg • Dysarthria/clumsy hand – Basis pontis • Dysarthria and clumsiness (i.e., weakness) of the hand, which often are most prominent when the patient is writing. • Pure sensory stroke – Thalamus • Persistent or transient numbness, tingling, pain, burning, or another unpleasant sensation on one side of the body. • Mixed sensorimotor stroke – Thalamus and adjacent posterior internal capsule • Hemiparesis or hemiplegia with ipsilateral sensory impairment Posterior circulation • • • • Posterior cerebral arteries Cerebellar arteries Vertebral arteries Basilar artery Posterior cerebral Artery • Supply midbrain, cerebral peduncles, medial temporal lobes, medial thalami, splenium of the corpus callosum,lateral ventriclar choroid plexus and bilateral occipital lobes. • Arises at the intersection of the posterior communicating artery and the basilar artery • Connects with the ipsilateral MCA and internal cerebral artery via the posterior communicating artery PCommA Clinical Syndrome • • • • Contralateral weakness Contralateral VF cut with macular sparing Contralateral sensory loss Posterior headache Cerebellar arteries • Posterior inferior cerebellar artery • Anterior inferior cerebellar artery • Superior cerebellar artery Posterior inferior cerebellar artery • Last branch off the vertebral artery • Supplies lateral medulla • Most of the inferior cerebellum and inferior vermis Clinical syndrome • • • • • • • • • Dysphagia Dysarthria Gait unsteadiness Ipsilateral limb ataxia Vertigo Hoarseness Ipsilateral Horner’s syndrome Ipsilateral hemianesthesia of the face Contralateral hemianesthesia of the limbs Anterior inferior cerebellar artery • • • • First paired branches off the basilar Supplies the inferior, lateral pons Middle cerebellar peduncle Strip of the ventral, anterior cerebellum(between the PICA and the SCA) Clinical syndrome • • • • • Vertigo Nystagmus Facial weakness Gait ataxia Acute unilateral deafness (internal auditory artery) Superior cerebellar artery Paired branches off basilar artery Supplies upper, lateral pons Superior cerebellar peduncle Most of the superior cerebellar hemisphere • Superior vermis • • • • Clinical syndrome • Ipsilateral cerebellar ataxias (middle and/or superior cerebellar peduncles) • Nausea and vomiting • Slurred (pseudobulbar) speech • Loss of pain and temperature over the opposite side of the body • Partial deafness • Tremor of the upper extremity • Ipsilateral Horner syndrome • Palatal myoclonus Brainstem infarctions • Basilar occlusion • Small vessel lacunar infarctions Basilar artery occlusion • Most important artery in the posterior circulation (the body) • Formed at the pontomedullary junction by the confluence of both vertebral arteries • Lies on the ventral surface of the pons • Gives off its median, paramedian, short, and long circumferential branches Clinical presentation • • • • • • • Hemiparesis or tetraparesis and facial paresis - 40-67% of cases Dysarthria and speech impairment - 30-63% of cases Vertigo, nausea, and vomiting - 54-73% of cases Visual disturbances - 21-33% of cases Altered consciousness - 17-33% of cases Convulsive-like movements along with hemiparesis (herald hemiparesis) Oculomotor signs – – – – – – Ipsilateral abducens palsy Ipsilateral conjugate gaze palsy Internuclear ophthalmoplegia One-and-a-half syndrome Ocular bobbing Skew deviation Clinical presentation • Locked-in syndrome: – Infarction of the basis pontis – Secondary to occlusive disease of the proximal and middle segments of the basilar artery, which leads to quadriplegia. spared level of consciousness, preserved vertical eye movements, and blinking. – Coma associated with oculomotor abnormalities and quadriplegia also indicates proximal basilar and midbasilar occlusive disease with pontine ischemia. • Top-of-the-basilar syndrome: – Upper brainstem and diencephalic ischemia caused by occlusion of the rostral basilar artery – Patients present with changes in the level of consciousness – Visual symptoms • Hallucinations and/or blindness. • Third nerve palsy and pupillary abnormalities are also frequent. • Motor abnormalities include abnormal movements or posturing. • Other reported signs of pontine ischemia include limb shaking, ataxia (usually associated with mild hemiparesis), facial weakness, dysarthria, dysphagia, and hearing loss. Syndrome?