Changes over Time in Intracranial Air in Patients with Cerebral Air Embolism: Radiological Study in Two Cases

Abstract

Cerebral air embolism can be easily identified on computed tomography (CT) scans. However, changes in the distribution and amount of intracranial air are not well known. We report two patients with cerebral air embolism and present imaging findings on the serial changes in the intracranial air. We thought that the embolic source was venous in one patient because CT showed air inflow in cortical veins in the bilateral frontal areas, reflecting air buoyancy. In the other patient, CT showed air inflow into not only the cortical veins but also the bilateral cerebral hemispheres and we thought this to be a paradoxical cerebral air embolism. We found that intracranial air can be promptly absorbed and while cerebral infarcts due to air are clearly visualized on diffusion-weighted images (DWI), the air may rapidly disappear from images. In patients with suspected cerebral air embolism whose CT findings show no intracranial air, DWI should be performed because it may reveal cerebral infarction due to cerebral air embolism.

A Rare Case of Cerebral Air Embolism Caused by Pulmonary Arteriovenous Malformation After Removal of a Central Venous Catheter

“…In our case, MRI revealed multiple infarcts in the cortical area. Other studies have reported similar MRI findings in cases with cerebral venous air embolism [6,7]. Cerebral infarcts are often observed in the cortical area near air bubbles [6].…”

“…Intravascular air can lead to both arterial and venous infarcts [6]. In our case, MRI revealed multiple infarcts in the cortical area.…”

“…Other studies have reported similar MRI findings in cases with cerebral venous air embolism [6,7]. Cerebral infarcts are often observed in the cortical area near air bubbles [6]. Mechanisms that lead to air embolism ischemia are blood flow obstruction, vasospasm, and thrombus formation due to platelet activation [6].…”

“…Cerebral infarcts are often observed in the cortical area near air bubbles [6]. Mechanisms that lead to air embolism ischemia are blood flow obstruction, vasospasm, and thrombus formation due to platelet activation [6]. The blood-brain barrier is compromised by the migration of air bubbles to the arteries and arterioles because of endothelial damage [8,9].…”

Iatrogenic Cerebral Air Embolism During Esophago-Gastroduodenoscopy

“…Arterial and venous air emboli usually affect the frontal and parietal lobes. However, it has been described that in arterial air emboli, punctate air emboli can be found in the brain parenchyma, trapped in arterial capillaries [ 14 ]. Most patients with a clinical suspicion of ischemic stroke require a noncontrast brain MRI.…”