Comparing tract-based spatial statistics and manual region-of-Interest labeling as diffusion analysis methods to detect white matter abnormalities in infants with hypoxic-Ischemic encephalopathy.
OBJECTIVE
To compare manual region of interest (ROI) labeling and tract-based spatial statistics (TBSS) by their ability to detect group-wise differences in fractional anisotropy (FA) in the neonatal brain.


METHODS
Diffusion-weighted data were obtained for nine infants with hypoxic-ischemic encephalopathy (HIE) (six males, three females; gestational age [GA] range, 36-40 weeks; mean GA, 37.8 weeks) and 11 healthy-control infants (10 males, 1 female; GA range, 36-40 weeks; mean GA, 38.4 weeks) at 3T. For manual ROI labeling, ROIs were drawn freehand for each subject in eight, clinically relevant brain regions. For TBSS, all FA data underwent an optimized, automated protocol for neonates. Each method was evaluated for detection of decreased FA in HIE infants, sensitivity, specificity, and variability.


RESULTS
FA values from manual ROI and TBSS were strongly correlated (r = 0.94, P < 0.0001). Both methods found decreased FA in most ROIs for HIE infants. There was no significant interaction between method and group, indicating a similar ability to detect FA differences (F(1,19) = 0.599, P = 0.449). Sensitivity (manual: 0.709, TBSS: 0.694, 95% CI [-0.136, 0.163], P = 0.856), specificity (manual and TBSS: 0.716, 95% CI [-0.133, 0.133], P = 1), and standard error (manual: 0.009, TBSS: 0.007) were comparable.


CONCLUSIONS
Manual ROI labeling and TBSS are comparable methods of diffusion analysis to detect group differences in FA in the neonatal brain.
Center for Neuroscience, West Virginia University, Morgantown, West Virginia, USA.
Monica T
MT
Ly
Department of Pediatrics, Child Neurology, West Virginia University School of Medicine, Morgantown, West Virginia, USA.
Tania U
TU
Nanavati
Department of Physiology and Pharmacology, West Virginia University, Morgantown, West Virginia, USA.
Christopher A
CA
Frum
Department of Pediatrics, Child Neurology, West Virginia University School of Medicine, Morgantown, West Virginia, USA.
Paola
P
Pergami
D001921:Brain / Q000473:pathology*; D056324:Diffusion Tensor Imaging / Q000379:methods*; D005260:Female; D006801:Humans; D020925:Hypoxia-Ischemia, Brain / Q000473:pathology*; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D007231:Infant, Newborn; D007232:Infant, Newborn, Diseases / Q000473:pathology; D008297:Male; D015588:Observer Variation; D010363:Pattern Recognition, Automated / Q000379:methods*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D062211:Spatio-Temporal Analysis; D066127:White Matter / Q000473:pathology*
diffusion tensor imaging; fractional anisotropy; hypoxic-ischemic encephalopathy; neonates; tract-based spatial statistics