TY - JOUR
T1 - In vivo DTI tractography of the rat brain
T2 - An atlas of the main tracts in Paxinos space with histological comparison
AU - Figini, Matteo
AU - Zucca, Ileana
AU - Aquino, Domenico
AU - Pennacchio, Paolo
AU - Nava, Simone
AU - Di Marzio, Alessandro
AU - Preti, Maria Giulia
AU - Baselli, Guseppe
AU - Spreafico, Roberto
AU - Frassoni, Carolina
PY - 2015/4/1
Y1 - 2015/4/1
N2 - Diffusion tensor imaging (DTI) is a magnetic resonance modality that permits to characterize the orientation and integrity of white matter (WM). DTI-based tractography techniques, allowing the virtual reconstruction of WM tract pathways, have found wide application in preclinical neurological research. Recently, anatomically detailed rat brain atlases including DTI data were constructed from ex vivo DTI images, but tractographic atlases of normal rats in vivo are still lacking. We propose here a probabilistic tractographic atlas of the main WM tracts in the healthy rat brain based on in vivo DTI acquisition. Our study was carried out on 10 adult female Sprague-Dawley rats using a 7. T preclinical scanner. The MRI protocol permitted a reliable reconstruction of the main rat brain bundles: corpus callosum, cingulum, external capsule, internal capsule, anterior commissure, optic tract. The reconstructed fibers were compared with histological data, proving the viability of in vivo DTI tractography in the rat brain with the proposed acquisition and processing protocol. All the data were registered to a rat brain template in the coordinate system of the commonly used atlas by Paxinos and Watson; then the individual tracts were binarized and averaged, obtaining a probabilistic atlas in Paxinos-Watson space of the main rat brain WM bundles. With respect to the recent high-resolution MRI atlases, the resulting tractographic atlas, available online, provides complementary information about the average anatomical position of the considered WM tracts and their variability between normal animals. Furthermore, reference values for the main DTI-derived parameters, mean diffusivity and fractional anisotropy, were provided. Both these results can be used as references in preclinical studies on pathological rat models involving potential alterations of WM.
AB - Diffusion tensor imaging (DTI) is a magnetic resonance modality that permits to characterize the orientation and integrity of white matter (WM). DTI-based tractography techniques, allowing the virtual reconstruction of WM tract pathways, have found wide application in preclinical neurological research. Recently, anatomically detailed rat brain atlases including DTI data were constructed from ex vivo DTI images, but tractographic atlases of normal rats in vivo are still lacking. We propose here a probabilistic tractographic atlas of the main WM tracts in the healthy rat brain based on in vivo DTI acquisition. Our study was carried out on 10 adult female Sprague-Dawley rats using a 7. T preclinical scanner. The MRI protocol permitted a reliable reconstruction of the main rat brain bundles: corpus callosum, cingulum, external capsule, internal capsule, anterior commissure, optic tract. The reconstructed fibers were compared with histological data, proving the viability of in vivo DTI tractography in the rat brain with the proposed acquisition and processing protocol. All the data were registered to a rat brain template in the coordinate system of the commonly used atlas by Paxinos and Watson; then the individual tracts were binarized and averaged, obtaining a probabilistic atlas in Paxinos-Watson space of the main rat brain WM bundles. With respect to the recent high-resolution MRI atlases, the resulting tractographic atlas, available online, provides complementary information about the average anatomical position of the considered WM tracts and their variability between normal animals. Furthermore, reference values for the main DTI-derived parameters, mean diffusivity and fractional anisotropy, were provided. Both these results can be used as references in preclinical studies on pathological rat models involving potential alterations of WM.
KW - DTI
KW - Histology
KW - MRI
KW - Rat brain
KW - Tractographic atlas
UR - http://www.scopus.com/inward/record.url?scp=84924863089&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84924863089&partnerID=8YFLogxK
U2 - 10.1016/j.mri.2014.11.001
DO - 10.1016/j.mri.2014.11.001
M3 - Article
C2 - 25482578
AN - SCOPUS:84924863089
VL - 33
SP - 296
EP - 303
JO - Magnetic Resonance Imaging
JF - Magnetic Resonance Imaging
SN - 0730-725X
IS - 3
ER -