Isolated ataxia after pure left insular cortex infarction

Acute insular infarction, due to its anatomic and functional complexity and wide connections, may present with various clinical presentations, such as somatosensory deficits, gustatory disorder, vestibular-like syndrome, cardiovascular disturbances, neuropsychological disorders, movement disorders, autonomic dysfunction and empathy impairment. However, there was no mention of the symptoms involving the cerebellar system in the related literature. We present a case of pure left insular cortex infarction with isolated truncal ataxia and demonstrate a crucial relationship between the left insular cortex and the cerebellar system. The possible connections are through the spinocerebellar and dentatorubrothalamic pathway. In conclusions, left insular cortex lesions should be considered in the differential diagnosis of isolated truncal ataxia.