Objective: To present three cases of young adults with lateral medullary ischaemic events associated with a hypoplastic vertebral artery (VA). All three patients had two additional atherosclerotic or non-atherosclerotic risk factors for stroke.
Patients and methods: One female, aged 40 years, and two males, aged 38 and 37 years, each with two risk factors for stroke, presented to the emergency department with acute onset of symptoms and findings consistent with lateral medullary syndrome. All three patients underwent emergency CT scan of the brain followed by MRI and magnetic resonance angiography (MRA).
Results: The CT scans were negative in all patients. MRI revealed a lateral medullary lesion in only one patient. All three patients had a hypoplastic VA ipsilateral to the clinical ischaemic event on MRA.
Conclusions: Hypoplasia of VA is not considered a risk factor for stroke as it is a common variant in up to 75% of the general population. However, in our patients, hypoplastic VA coexisted with two risk factors and resulted in stroke. Thus although a hypoplastic VA may not be an uncommon asymptomatic finding, it may contribute to stroke if additional risk factors are present.