[Volumetric measurements of the hippocampus and amygdala with MRI in healthy adults].
BACKGROUND
Volumetric analysis of brain magnetic resonance images (MRI) measures structural changes associated with neurological and neuropsychiatric disorders. In recent years several studies have shown the utility of the volumetric measurement of the medial temporal lobe structures, especially the amygdala and the hippocampus in temporal lobe epilepsy, memory disorders, Alzheimer disease and schizophrenia.


OBJECTIVE
The purpose of this study was to measure and establish our normal values of the hippocampus and amygdala volumes.


METHODS
All studies were performed using a 1.0 T Siemens unit with FISP 3D sequence. One millimeter, contiguous coronal scans of 40 healthy volunteers aged 19-26 years were obtained. The regions of interest were outlined using a mouse driven cursor. To determine the anatomic boundaries of the hippocampus and the amygdala the authors followed a generally accepted protocol previously described by C. Watson.


RESULTS
The mean right and left hippocampal volumes were 2.12 cm3 (SD = 0.31) and 2.07 cm3 (SD = 0.3) and the mean right and left amygdaloid volume were 1.19 cm3 (SD = 0.19) and 1.2 cm3 (SD = 0.2) respectively. The mean asymmetry between the right and left hippocampus and amygdala was 3.17% and 3.48%, respectively. The inter-observer reliability range (alpha) was between 0.97 and 0.77. Subregional analysis of hippocampus was calculated as well.


CONCLUSIONS
Normal volumetric data measured in our study fell in the midrange of the values in the literature. The volumetric analysis of the hippocampal subregions may allow assessment of providing more sensitive determination of the atrophic area, which may be important in epileptic disorders.
Horváth
Krisztina
K
Pécsi Tudományegyetem, Altalános Orvostudományi Kar, Neurológia Klinika.
Kövér
Ferenc
F
Kovács
Norbert
N
Kállai
János
J
Nagy
Ferenc
F
D000328:Adult; D000679:Amygdala / Q000033:anatomy & histology*; D005260:Female; D006624:Hippocampus / Q000033:anatomy & histology*; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging / Q000379:methods; D015588:Observer Variation; D012016:Reference Values; D015203:Reproducibility of Results