Original article Diffusion tensor MR imaging in spinal cord injury Maria M. D’souza* ,a , Ajay Choudhary b , Mahesh Poonia a , Pawan Kumar a , Subash Khushu a a INMAS, Brig SK Majumdar Marg, Delhi, 110054, India b Dept. of Neurosurgery, RML Hospital, New Delhi, India A R T I C L E I N F O Article history: Accepted 20 February 2017 Keywords: Diffusion tensor imaging Spinal cord injury Neurological outcome A B S T R A C T Background: The ability of diffusion tensor imaging (DTI) to complement conventional MR imaging by diagnosing subtle injuries to the spinal cord is a subject of intense research. We attempted to study change in the DTI indices, namely fractional anisotropy (FA) and mean diffusivity (MD) after traumatic cervical spinal cord injury and compared these with corresponding data from a control group of individuals with no injury. The correlation of these quantitative indices to the neurological profile of the patients was assessed. Material and methods: 20 cases of acute cervical trauma and 30 age and sex matched healthy controls were enrolled. Scoring of extent of clinical severity was done based on the Frankel grading system. MRI was performed on a 3T system. Following the qualitative tractographic evaluation of white matter tracts, quantitative datametrics were calculated. Results: In patients, the Mean FA value at the level of injury (0.43+/À0.08) was less than in controls (0.62+/À0.06), which was statistically significant (p value <0.001). Further, the Mean MD value at the level of injury (1.30+/À0.24) in cases was higher than in controls (1.07+/À0.12, p value <0.001). Statistically significant positive correlation was found between clinical grading (Frankel grade) and FA values at the level of injury (r value = 0.86). Negative correlation was found between clinical grade and Mean MD at the level of injury (r value = À0.38) which was however statistically not significant. Conclusion: Quantitative DTI indices are a useful parameter for detection of spinal cord injury. FA value was significantly decreased while MD value was significantly increased at the level of injury in cases as compared to controls. Further, FA showed significant correlation with clinical grade. DTI could thus serve as a reliable objective imaging tool for assessment of white matter integrity and prognostication of functional outcome. © 2017 Elsevier Ltd. All rights reserved. Introduction Spinal trauma can result in devastating medical, social, emotional and financial consequences, especially when associated with neurological damage. Diagnostic imaging plays a crucial role in evaluating and detecting spinal trauma. The imaging assessment of these patients has undergone dramatic changes over the past several years. Today, conventional MR imaging is performed routinely to demonstrate soft tissue and spinal cord injuries in spinal trauma [1–3]. Many advantages of MRI such as higher contrast resolution, absence of bony artifacts, multiplanar capa- bility, and choice of various pulse sequences make it possible to diagnose spinal trauma more accurately. Conventional MRI relies heavily on changes in signal intensity for depiction of pathology. However, the literature is ambivalent about the relationship between MRI findings and extent of neurological damage. According to certain reports, edema and hemorrhage in the spinal cord following trauma are well demonstrated by MR imaging and may help to predict neurologic outcome [4–6]. However, some studies suggest that although spinal cord edema, hemorrhage and interstitial fibrosis will appear as changes in signal intensity on conventional MRI, they may not always be successful in the prediction of functional deficit [7]. Diffusion tensor imaging (DTI) is a novel MR imaging technique which assesses the microstructural integrity of nerve fiber tracts. It is based on the simple principle of diffusion of water molecules in tissue. In neuronal tissue, this mobility is restricted to one particular direction by the presence of biological barriers such as cell membranes and myelin sheath, hence the diffusion is termed anisotropic. Interruption or alteration of this linear molecular diffusion at any point along the neuron can be the first sign of a * Corresponding author. E-mail address: maria.md@rediffmail.com (M.M. D’souza). http://dx.doi.org/10.1016/j.injury.2017.02.016 0020-1383/© 2017 Elsevier Ltd. All rights reserved. Injury, Int. J. Care Injured xxx (2016) xxx–xxx G Model JINJ 7094 No. of Pages 5 Please cite this article in press as: M.M. D’souza, et al., Diffusion tensor MR imaging in spinal cord injury, Injury (2017), http://dx.doi.org/ 10.1016/j.injury.2017.02.016 Contents lists available at ScienceDirect Injury journal homepa ge: www.elsev ier.com/locate /injury