title: Protocol for volumetric segmentation of medial temporal structures using high-resolution 3-D magnetic resonance imaging.
abstract: Quantitative analysis of brain structures in normal subjects and in different neurological conditions can be carried out in vivo through magnetic resonance imaging (MRI) volumetric studies. The use of high-resolution MRI combined with image post-processing that allows simultaneous multiplanar view may facilitate volumetric segmentation of temporal lobe structures. We define a protocol for volumetric studies of medial temporal lobe structures using high-resolution MR images and we studied 30 healthy subjects (19 women; mean age, 33 years; age range, 21-55 years). Images underwent field non-homogeneity correction and linear stereotaxic transformation into a standard space. Structures of interest comprised temporopolar, entorhinal, perirhinal, parahippocampal cortices, hippocampus, and the amygdala. Segmentation was carried out with multiplanar assessment. There was no statistically significant left/right-sided asymmetry concerning any structure analyzed. Neither gender nor age influenced the volumes obtained. The coefficient of repeatability showed no significant difference of intra- and interobserver measurements. Imaging post-processing and simultaneous multiplanar view of high-resolution MRI facilitates volumetric assessment of the medial portion of the temporal lobe with strict adherence to anatomic landmarks. This protocol shows no significant inter- and intraobserver variations and thus is reliable for longitudinal studies.
authors.affiliation: Neuroimage Laboratory, Department of Neurology, State University of Campinas, Campinas, Brazil.
authors.forename: Leonardo
authors.initials: L
authors.lastname: Bonilha
authors.forename: Eliane
authors.initials: E
authors.lastname: Kobayashi
authors.forename: Fernando
authors.initials: F
authors.lastname: Cendes
authors.forename: Li
authors.initials: L
authors.lastname: Min Li
mesh_terms: D000328:Adult; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods*; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D011859:Radiography; D015203:Reproducibility of Results; D013702:Temporal Lobe / Q000000981:diagnostic imaging*