Clival Osteomyelitis and Abscess Leading to Bilateral Pontine Infarction and Basilar Artery Pseudoaneurysm

Brainstem infarction can be a critical condition, typically due to ischemic mechanisms such as large artery atherosclerosis, small vessel disease, or cardioembolic sources. In rare instances, infectious or inflammatory etiologies may lead to brainstem infarction, posing substantial diagnostic complexities. We report the case of a 74-year-old man presenting bilateral pontine infarctions secondary to clival osteomyelitis and an adjacent abscess, which was further complicated by a basilar artery pseudoaneurysm and subsequent subarachnoid hemorrhage. This case highlights the importance of considering uncommon infectious causes of brainstem infarction, especially in patients with intricate medical backgrounds and immunosuppression.