For the latest COVID-19 campus news and resources, visit

Search Close Search
Page Menu

Strokes involving the vertebral-basilar vessels or branches

Blocked Vessel/ Branch
Deficit Pattern

One vertebral artery in the rostral medulla, or in some cases its PICA branch 

termed "Wallenberg's syndrome
• sensory loss on ipsilateral side of face but contralateral trunk and limbs
• ipsilateral ataxia
• ipsilateral Horner's syndrome
• ipsilateral vocal cord paralysis
• hoarseness
• impaired swallowing
• vertigo, nausea, vomiting
Penetrating paramedian basilar branches in pons pure motor stroke
• contralateral hemiplegia
• involvement of face depends on infarction location
Basilar occlusion affecting the rostral pons bilaterally termed "locked-in syndrome"
• complete bilateral paralysis rendering patient motionless and mute yet capable of perceiving sensory stimuli
• vertical components of 3rd and 4th nerve function may be spared
Penetrating PCA branches supplying thalamus • pure sensory loss
• involves face, arm, trunk and leg
• initially hemianesthesia but may eventually develop into thalamic pain syndrome with painful dysesthesias in affected parts
Unilateral cortical branches of PCA supplying occipital lobe • contralateral homonymous hemianopsia
• may have macular sparing (central vision) depending on location of PCA-MCA border zone
Bilateral occlusion of all PCA cortical branches distal to thalamic penetrators • inability to form and/or consolidate new memories
• cortical blindness; in acute stage, possible denial of any vision problem