Teaching NeuroImages: Distinct brain microhemorrhage pattern in critical illness associated with respiratory failure.

Abstract

A 51-year-old man with dementia presented with altered mental status and unremarkable initial brain CT and MRI. Hospitalization was complicated by aspiration pneumonia, hypoxia, and acute respiratory distress syndrome requiring intubation. He improved with antibiotics, but 1 week later developed seizures. MRI revealed new multiple microhemorrhages involving the subcortical white matter, internal capsules, and corpus callosum, sparing the deep white matter and deep gray nuclei (figure). This distinctive pattern is seen in critically ill patients with respiratory failure1 and resembles high altitude exposure.2 It is important to distinguish this from other causes of microhemorrhages including hypertension, diffuse axonal injury, and amyloid angiopathy.