Rationale: Due to the rarity of bilateral cerebral peduncular infarction (BCPI), its symptoms and prognosis are not clear. It is necessary to collect cases of pure cerebral peduncular infarction, explore the etiology and anatomy of midbrain infarction in depth, and develop meaningful tools for explaining clinical symptoms and predicting prognosis of patients.
Patient concerns: We here provide a case of isolated BCPI with uncommon symptoms of ataxia, dysarthria, sensory disturbance, normal muscular strength, and full eye movements.
Diagnoses: Diffusion weighted images and apparent diffusion coefficient map of our patient revealed acute and isolated bilateral peduncle cerebrum infarction.
Interventions: Drugs that could improve circulation and antiplatelet were used in therapy.
Outcomes: The infarct size was enlarged and new infarction was identified in the splenium of the corpus callosum and pons. The patient developed progressed disorder of consciousness and died at the eleventh day.
Lessons: We inferred that the symptoms of ataxia, dysarthria, sensory disturbance, and mild paresis of the extremities could be prominent features of patients with pure cerebral peduncular infarction. We hypothesize that pure BCPI is also related to severe basilar artery stenosis or occlusion and there is no collateral circulation from PCA. This may explain the corresponding distribution of cerebral peduncular infarction and its poor prognosis. For these reasons, exploring etiology and anatomy of midbrain infarction in depth would have clinical value for predicting symptoms and prognosis.