Advanced MRI Morphologic Study Shows No Atrophy in Healthy Individuals with Hippocampal Hyperintensity

SUMMARY: We have already shown that brain MR imaging of healthy individuals frequently reveals either unilateral or bilateral Hh, which is considered a hallmark of hippocampal sclerosis. We performed a follow-up (5-year interval) clinical and advanced imaging study of these individuals to address whether Hh may have masked occult brain atrophy or contributed to a later onset of epilepsy. Subjects with Hh (n = 13) underwent a detailed clinical-imaging protocol, with a 3T scan and were studied with automated hippocampal segmentation (FreeSurfer), whole brain voxel-based morphometry, and shape analysis. All 13 subjects with Hh had normal neurologic examination findings with no cognitive impairment. Multimodal structural neuroimaging methods did not show clear evidence of significant volumetric changes between subjects with or without Hh. We clearly showed that Hh is not associated with any occult brain atrophy; furthermore, none of the healthy subjects with MR imaging evidence of Hh developed epilepsy or trouble with cognition.