Could linear MRI measurements of hippocampus differentiate normal brain aging in elderly persons from Alzheimer disease?

• Published in: Surgical and radiologic anatomy (English ed.) Vol. 29; no. 1; pp. 77 - 81
• Main Authors: TARROUN, Abdullah, BONNEFOY, Marc, BOUFFARD-VERCELLI, Juliette, GEDEON, Claire, VALLEE, Bernard, COTTON, Francois
• Format: Journal Article
• Language: English
• Published: Berlin Springer 01.02.2007; Springer Nature B.V; Springer Verlag (Germany)
• Subjects: Acoustics; Aged; Aged, 80 and over; Aging; Aging - pathology; Alzheimer Disease - pathology; Alzheimer's disease; Anatomy & physiology; Atrophy; Bioengineering; Biological and medical sciences; Brain; Brain - pathology; Computer Science; Degenerative and inherited degenerative diseases of the nervous system. Leukodystrophies. Prion diseases; Engineering Sciences; Female; General aspects; Hippocampus - pathology; Humans; Image Processing; Imaging; Life Sciences; Magnetic Resonance Imaging; Male; Mechanics; Medical Imaging; Medical Physics; Medical sciences; Neurology; NMR; Nuclear magnetic resonance; Nuclear medicine; Physics; Signal and Image Processing; Human; Brain; Temporal lobe; Nervous system diseases; Senescence; Alzheimer disease; MRI; Ageing; Anatomy; Normal; Nuclear magnetic resonance imaging; Cerebral disorder; Medicine; Treatment; Surgery; Central nervous system disease; Aging; Medical imagery; Degenerative disease; Elderly; Age; Hippocampus; Quantitative analysis
• ISSN: 0930-1038; 1279-8517
• DOI: 10.1007/s00276-006-0163-3

Although mild progressive specific structural brain changes are commonly associated with normal human aging, it is unclear whether automatic or manual measurements of these structures can differentiate normal brain aging in elderly persons from patients suffering from cognitive impairment. The objective of this study was primarily to define, with a standard high resolution MRI, the range of normal linear age-specific values for the hippocampal formation (HF), and secondarily to differentiate hippocampal atrophy in normal aging from that occurring in Alzheimer disease (AD). Two MRI-based linear measurements of the hippocampal formation at the level of the head and of the tail, standardized by the cranial dimensions, were obtained from coronal and sagittal T1-weighted MR images in 25 normal elderly subjects, and 26 patients with AD. In this study, dimensions of the HF have been standardized and they revealed normal distributions for each side and each sex: the width of the hippocampal head at the level of the amygdala was 16.42 +/- 1.9 mm, and its height 7.93 +/- 1.4 mm; the width of the tail at the level of the cerebral aqueduct was 8.54 +/- 1.2 mm, and the height 5.74 +/- 0.4 mm. There were no significant differences in standardized dimensions of the HF between sides, sexes, or in comparison to head dimensions in the two groups. In addition, the median inter-observer agreement index was 93%. In contrast, the dimensions of the hippocampal formation decreased gradually with increasing age, owing to physiological atrophy, but this atrophy is more significant in the group of AD.