Astasia induced by a small unilateral cerebral infarct in the posterolateral portion of the thalamus: a case report

An 87-year-old woman was admitted to our hospital because of disturbance in standing unsupported. She showed mild cerebellar ataxia on the right side. Although there was no paresis, she had marked truncal instability and fell backward or to the left side without support. Magnetic resonance imaging (MRI) showed a small infarct in the posterolateral portion of the right thalamus, and magnetic resonance angiography showed severe stenoses of the intracranial cerebral arteries. The patient was diagnosed with thalamic astasia based on clinical symptoms and MRI findings, and was treated for atherothrombotic cerebral infarction. During the following 26 days, her astasia gradually improved, and she was transferred to a rehabilitation hospital nearby. Thalamic astasia is very rare and may be overlooked. It is important to recognize astasia as a thalamic symptom.