Magnetic resonance diffusion tensor imaging (MRDTI) and tractography in children with septo-optic dysplasia.
BACKGROUND
Septo-optic dysplasia (SOD) refers to a heterogeneous group of midline brain developmental anomalies, with optic nerve hypoplasia (ONH) being one of the morphologic correlates of the condition. Traditionally, ONH has been diagnosed on fundoscopic exam. Conventional MRI is used in cases of suspected ONH to identify associated brain abnormalities and to compare findings to the fundoscopic exam. Advances in magnetic resonance diffusion tensor imaging (MRDTI) permit in vivo, noninvasive, quantitative characterization of the entire visual pathway at 3.0 T.


OBJECTIVE
To investigate the feasibility of MRDTI at 3.0 T in children with SOD to evaluate the entire visual pathway.


METHODS
MRDTI at 3T was performed in two children with SOD and seven age-matched controls. Manual region-of-interest analysis was used to evaluate the tensor metrics of the optic nerves. Deterministic tractography was used to evaluate the tensor metrics of the optic radiations.


RESULTS
The SOD patients demonstrated a significant decrease in anisotropy and increase in mean diffusivity of the optic nerves and radiations compared to the control subjects.


CONCLUSIONS
This study demonstrates the feasibility of MRDTI to evaluate the entire visual pathway in children, and it demonstrates pre- and post-chiasmatic diffusion tensor abnormalities in SOD patients.
Salmela
Michael B
MB
University of Vermont College of Medicine-Fletcher Allen Health Care, 111 Colchester Ave., Burlington, VT 05401, USA. msalmela@uvm.edu
Cauley
Keith A
KA
Nickerson
Joshua P
JP
Koski
Chris J
CJ
Filippi
Christopher G
CG
D001921:Brain / Q000473:pathology*; D056324:Diffusion Tensor Imaging / Q000379:methods*; D005260:Female; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D009413:Nerve Fibers, Myelinated / Q000473:pathology*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D025962:Septo-Optic Dysplasia / Q000473:pathology*