Long-term cognitive and neuroanatomical stability in patients with anoxic amnesia: A Case Report

ABSTRACT

Background: Anoxia can result in selective hippocampal damage with associated impairments in declarative memory. Whilst memory impairments and brain structures are thought to be stable, there are little data regarding the effects of ageing or change over time in patients with amnesia from anoxic brain injury.

Methods: To assess change over time, we compared structural magnetic resonance imaging (MRI) with data obtained over ten years previously in two well-characterized patients with amnesia (JRW and RS) who experienced an anoxic brain injury. Six healthy, age-matched control participants were recruited to compare brain volumes with the patients at Time 2. Wechsler adult intelligence scale-revised and Wechsler memory scale-revised scores were compared to scores on the same tests administered 13 and 19 years prior.

Results: Patients with amnesia had significantly smaller hippocampal volumes than controls, but comparable medial temporal lobe and ventricular volumes. Memory, intellectual function and brain volumes were stable over time.

Conclusion: Patients with an amnesia due to anoxia have memory impairments and smaller hippocampal volumes compared to controls; however, memory, intelligence and structural volumes remain stable over time. At ages 50 and 57, they do not appear to have early age-associated cognitive decline that is sometimes observed in patients with traumatic brain injury.

KEYWORDS:

• Hippocampus
• anoxia
• memory
• amnesia
• medial temporal lobe
• intelligence

Acknowledgments

The authors would like to thank Nathan Giles, Alex Dresden and Seth Spencer for their dedication in the collection of brain volumes.

Declaration of Interest

The authors report no conflicts of interest.