Delayed-onset Reversible Cortical Blindness after Resuscitation from Cardiac Arrest

Abstract

We present a patient who presented with cortical blindness (CB) 1 week after repeated cardiac arrest while undergoing treatment for an acute myocardial infarction. He had been revived within 5 min in each instance and was apparently neurologically normal until presentation. Magnetic resonance imaging showed subtle hyperintensities on fluid-attenuated inversion recovery and diffusion-weighted imaging in both temporooccipital cortices. A rapid recovery over the next 2 weeks was remarkable for the appearance of metamorphopsia. CB may present even days to weeks after hypoxic-ischemic encephalopathy following cardiac arrest, even in patients apparently without immediate neurological sequelae. The pathogenesis of this phenomenon remains to be fully elucidated, but is likely to be due to delayed effects of anoxia on the occipital cortex and may be analogous to the previously described syndrome of delayed posthypoxic leukoencephalopathy. Prognosis for visual recovery appears to be good.

Keywords: Cardiac arrest; cortical blindness; hypoxic-ischemic encephalopathy; occipital cortex.

Figure 1

Magnetic resonance imaging of the brain 10 days after onset of neurological symptoms shows subtle hyperintensities in bilateral parietooccipital cortices on fluid-attenuated inversion recovery and diffusion-weighted imaging (asterisks)

Figure 2

Visual fields were normal 2 weeks after onset of blindness