Unexpected Cardiac Arrest During MRI in a Patient With Acute Brainstem Infarction: A Case Report and Imaging Insights

Figures

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  Figure 1. Initial MRI findings on hospital admission. (a) Diffusion-weighted imaging demonstrates acute ischemic changes in the right brainstem, with restricted diffusion in the right vertebral artery territory (arrow). (b) Fluid-attenuated inversion recovery image shows chronic ischemic changes in cerebral white matter. (c) T2-weighted imaging (T2*-WI) depicts no abnormal venous or arterial engorgement at this stage. (d) Another slice of T2*-WI shows no significant vascular abnormalities. (e) The source images of magnetic resonance angiography (MRA) show normal arterial blood flow signals except for the right vertebral artery (arrows). (f) Maximum intensity projection of the MRA highlights the absence of flow in the right vertebral artery, correlating with brainstem ischemia (arrow).

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  Figure 2. MRI findings during a follow-up scan. (a) Diffusion-weighted imaging shows a slight expansion of the ischemic area, with increased diffusion restriction in the right brainstem compared to the initial scan (arrow). (b) Fluid-attenuated inversion recovery image remains largely unchanged from the initial scan. (c) T2*-weighted imaging (T2*-WI) shows dilated cerebral arteries (arrows) and veins (arrow heads) as low signal intensity. (d) Another T2*-WI slice shows venous congestion as low signal intensity (arrow heads). (e) Magnetic resonance angiography (MRA) source image displays the absence of arterial blood flow signals, which was initially misinterpreted as a technical malfunction. (f) Maximum intensity projection of the MRA confirms the complete loss of cerebral arterial flow, correlating with the patient’s cardiac arrest.