“Such knowledge as we have of these steps is derived from casual glimpses afforded when, as the outcome of one of Nature’s experiments, some particular line is interfered with…” E Garrod. Inborn errors of metabolism

Giannopoulos and colleagues,¹ in a paper in this issue of J Neurol Neurosurg Psychiatry, report three instances of lateral medullary infarcts in young patients (average age 38 years) associated with occlusion of ipsilateral hypoplastic vertebral arteries (see page 987).¹ All three patients had high blood pressure and one had hyperlipidaemia.

The two vertebral arteries are very often asymmetrical. Chuang et al investigated 191 patients with acute ischaemic stroke and found that 11.5% had a unilateral hypoplastic vertebral artery.² They found a significant relationship between vertebral artery …