Posterior Cerebral Artery Symptoms and signs Postcommunal PCA

Posterior Cerebral Artery Symptoms and signs: • Postcommunal PCA – Ventrolateral thalamus • sensory symptoms, usually paresthesias • Motor symptoms include mild hemiparesis, clumsiness and ataxia – PCA hemispheric infarction: • Contralateral homonymous hemianopia (striate cortex, optic radiation) • Macular region is often spared if occipital pole not affected

Posterior Cerebral Artery Symptoms and signs: • Dominant hemisphere infarction: – Alexia without agraphia(splenium of corpus callosum) – Visual agnosia (medial temporal lobe) • Non dominant hemisphere: – Neglect of contralateral visual field – Constructional apraxia

Panhemispheric Infarcts Etiology: – Total or partial anterior circulation occlusion – 17% of strokes Symptoms and signs: – Variété massive de l`hemiplégie (MCA) – Delayed (48 -72 hr) impaired consciousness

Panhemispheric Infarcts

Medullary infarcts Anatomy and supply areas: perforating branches from PICA, AICA, basilar

Medullary infarcts Lateral medullary infarcts (Wallenberg’s Syndrome) • Etiology: – Infarction of the lateral medulla and cerebellum caused by PICA occlusion – Sudden in 40%, may be progressive over 2448 hr or present as TIA – Vertebral artery dissection in 75% of cases

Medullary infarcts

Medullary infarcts

Medullary infarcts • Symptoms and signs: – Gait ataxia – Vertigo – Ipsilateral limb clumsiness(cerebellar) – Hypoesthesia of contraleral limbs(crossed spinothalamic) and ipsilateral face(uncrossed trigeminal) – Ipsilateral Horner’s – If AICA involved(lateral inferior pons) • Deafness, tinnitus, facial paresis

Lacunar Syndromes • Occlusion of small perforating arteries • 80% of lacunes are silent • Pure motor stroke – Commonest lacunar syndrome – Usually involves antrior part of posterior limb or internal capsule – Can occur also from basis pontis lacune • Pure sensory stroke: – Only 6% of total lacunar strokes – Thalamus or anterior limb of internal capsule

References • Stroke Syndromes: Bogousslavsky and Caplan eds. Cambridge University press 1995 • Introduction to cerebral angiography: A. G. Osborn auth, Harper and Row publishers, 1980