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Table of Contents
ORIGINAL ARTICLE
Year : 2020  |  Volume : 7  |  Issue : 1  |  Page : 44-50

Role of diffusion tensor imaging scores in patients with spinal trauma


Department of Radiodiagnosis, Teerthanker Mahaveer Medical College and Research Centre, Moradabad, Uttar Pradesh, India

Date of Submission18-Mar-2020
Date of Acceptance01-May-2020
Date of Web Publication11-Jun-2020

Correspondence Address:
Dr. Shruti Chandak
Department of Radiodiagnosis, Teerthanker Mahaveer Medical College and Research Centre, Moradabad - 244 001, Uttar Pradesh
India
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Source of Support: None, Conflict of Interest: None


DOI: 10.4103/ami.ami_22_20

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  Abstract 

Background: Many patients of spinal trauma who have an apparently normal conventional magnetic resonance imaging (MRI) scan ultimately progress to neurological degradation in the long run. Diffusion tensor imaging (DTI) can play a vital role in such patients and can be used to assess the true extent of injury. Aims: The aims are to study the utility of DTI in detecting abnormalities in patients with spinal cord trauma and to obtain DTI scores. Materials and Methods: The study comprised 30 individuals including 20 cases and 10 apparently healthy controls who underwent conventional MRI, followed by DTI of involved spine. Fractional anisotropy (FA) and apparent diffusion coefficient (ADC) values were obtained by planning three regions of interest in the spinal cord at, above, and below the level of trauma. Results: Signal changes in the cord on conventional MRI were seen in 8 cases and were absent in 12. A significant difference was observed in mean FA values at the level of injury in cases without any change in signal intensity in the cord on conventional MRI (0.391 ± 0.12) as compared to controls (0.65 ± 0.165) as well as in mean ADC values in cases (1.534 ± 0.511) and controls (1.132 ± 0.616). Conclusions: DTI is an invaluable modality in assessment of the spinal cord following traumatic injury because it can detect subtle disruption of white matter leading to significant difference in the FA and ADC values.

Keywords: Apparent diffusion coefficient, diffusion tensor imaging, fractional anisotropy, magnetic resonance imaging, spinal cord trauma


How to cite this article:
Malhotra A, Chaudhary M, Agarwal A, Chandak S, Singla D. Role of diffusion tensor imaging scores in patients with spinal trauma. Acta Med Int 2020;7:44-50

How to cite this URL:
Malhotra A, Chaudhary M, Agarwal A, Chandak S, Singla D. Role of diffusion tensor imaging scores in patients with spinal trauma. Acta Med Int [serial online] 2020 [cited 2020 Oct 1];7:44-50. Available from: http://www.actamedicainternational.com/text.asp?2020/7/1/44/286418


  Introduction Top


Spinal trauma is one of the important causes of morbidity throughout the world. The increasing number of high-speed Road Traffic Accidents has led to a drastic rise in number of patients with traumatic spinal cord injury (TSCI). TSCI leads to potentially upsetting consequences regarding physical, emotional, social, and vocational conditions of the patients. It has a very significant impact over lives of not only the injured persons but also their families as well. Without timely treatment and proper rehabilitation, there is the risk of lifelong complications of motor, sensory, and autonomic dysfunction. The prognosis of neurological recovery following TSCI is difficult and uncertain.

Radiography and multidetector computed tomography are the investigations used for detection of bony spinal injuries. Magnetic resonance imaging (MRI) is indispensable for the assessment of injuries involving the spinal cord and soft tissues and is being extensively used as an ideal noninvasive technique for evaluation of patients with TSCI.[1] However, there are many patients of spinal trauma who have an apparently normal conventional MRI scan and ultimately progress to neurological degradation in the long run. Diffusion tensor imaging (DTI), being a relatively newer MRI technique, has the property of noninvasively producing quantitative information regarding the direction as well as integrity of the white matter tracts and to detect pathology in those areas that are apparently normal on the conventional MRI.[2],[3],[4] The role of DTI to detect abnormalities in the spinal cord which appears normal on conventional MRI has been proposed previously, and thus, it can be used to assess the true extent of injury.[5]

In this study, we aim to obtain DTI parameters in patients with spinal trauma and to compare them with apparently healthy controls and also to find the correlation between conventional MRI spine and DTI scores in patients of traumatic spinal injury.


  Materials and Methods Top


The institutional ethical committee approved the study. All the patients involved in our study were enrolled only after obtaining written informed consent. The study population comprised 30 individuals including 10 apparently healthy age- and sex-matched controls for comparison purpose. Patients with spinal trauma (within 2 weeks of injury) coming to the radiology department for spinal MRI were included in the study as cases. Patients undergoing spinal MRI for other indications such as low backache who had a normal conventional MRI were taken as controls. Patients having contraindication for undergoing MRI were excluded from the study. All patients underwent MRI of the spine using 1.5 Tesla Siemens Avanto machine using spine coils. Conventional MRI images were obtainedfirst, followed by DTI of the involved spine. Apparent diffusion coefficient (ADC) and fractional anisotropy (FA) values were obtained by planning region of interest in the spinal cord at, above, and below the level of trauma in cases as well as controls [Figure 1]. Signal intensity was considered increased in conventional MRI T2-weighted sequence if there was a hyperintense signal in the cord at the site of injury as compared to the unaffected spinal cord.
Figure 1: (a) Magnetic resonance imaging T2-weighted sagittal image in a healthy control showing normal spinal cord. (b) Diffusion tensor imaging image showing placement of three regions of interest. (c) Chart showing normal fractional anisotropy and apparent diffusion coefficient values at the three regions of interest

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The data were entered in Microsoft Excel sheet (2010 version, Microsoft Corporation, Redmond, Washington, USA). Statistical analysis was performed using SPSS analyzer (IBM Corp. Released 2013. IBM SPSS Statistics for Windows, Version 22.0. Armonk, NY: IBM Corp). Mean and standard deviation were obtained. The results were considered to be “statistically significant” if the P values were below 0.05.


  Results Top


The study consists of 30 individuals, with 20 cases and 10 controls. The mean age of the cases was 38.8 years and that of controls was 40.4 years.

The mean ADC value between cases and controls was compared using the unpaired Student's t-test [Table 1]. No significant difference in mean ADC values was noted above and below the level of trauma among cases and controls. However, the mean ADC value at injury level among cases (1.58 ± 0.52) was significantly more as compared to values in controls (1.132 ± 0.616). The mean FA value was also similarly compared between cases and controls [Table 2]. The mean FA value at the level of trauma among cases (0.334 ± 0.155) was significantly lesser than that of controls (0.65 ± 0.165) [Figure 2].
Table 1: Comparison of mean apparent diffusion coefficient value between cases and controls

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Table 2: Comparison of mean fractional anisotropy value between cases and controls

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Figure 2: (a) Magnetic resonance imaging T2-weighted sagittal image in a trauma patient showing compression fracture of lumbar vertebra. (b) Diffusion tensor imaging image showing placement of three regions of interest at, above, and below the level of injury. (c) Chart showing reduced fractional anisotropy and raised apparent diffusion coefficient values at injury level

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The Chi-square test was used to analyze the signal changes in the cord on conventional MRI, and this was compared between the cases and the control group [Table 3]. Signal intensity changes in the spinal cord on conventional MRI were seen in 8 cases and were absent in 12.
Table 3: Comparison of cord intensity changes on conventional magnetic resonance imaging sequences in cases and controls

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The DTI values were also compared at the level of trauma in cases without cord signal changes and controls [Table 4]. The mean FA value at injury level in cases without any cord intensity changes on standard MRI (0.391 ± 0.12) was significantly lesser compared to controls (0.65 ± 0.165). The mean ADC value at injury level among cases without any changes in the cord signal intensity (1.534 ± 0.511) was significantly higher as compared to controls (1.132 ± 0.616) [Figure 3].
Table 4: Comparison of diffusion tensor imaging values in cases without signal intensity changes and controls

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Figure 3: (a) Magnetic resonance imaging T2-weighted sagittal image in traumatic injury patient showing normal signal intensity of the spinal cord. (b) Diffusion tensor imaging image showing placements of three regions of interest. (c) Chart showing reduced fractional anisotropy and raised apparent diffusion coefficient values in the cord despite normal conventional magnetic resonance imaging

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  Discussion Top


Detection and assessment of spinal trauma is primarily dependent on diagnostic imaging. Tremendous changes have occurred in the imaging evaluation of these patients in the last few years. MRI is presently modality of choice for evaluating patients after TSCI, especially among cases of Spinal Cord Injury without Radiographic Abnormality (SCIWORA), which has been defined “as clinical symptoms of traumatic myelopathy with no radiographic or computed tomographic features of spinal fracture or instability.”[6] Nowadays, conventional MRI is routinely performed to delineate injuries to the spinal cord, ligaments, and other soft tissues. The numerous benefits of MRI such as better contrast resolution, multiplanar imaging, and different sequences make it an excellent modality to diagnose spinal injuries more precisely.[7],[8],[9]

Conventional MRI is based mainly on signal intensity alteration for portrayal of abnormality.[10] Past studies reveal uncertainty about the association of MRI findings and the extent of neurological injury, although spinal cord edema and hemorrhage may help to forecast neurologic outcome.[11],[12],[13] On the other hand, some authors propose that myeloedema and hemorrhage may not effectively estimate the actual functional neurological deficit.[14]

DTI has been estimated to be an innovative MRI sequence which evaluates the integrity of microstructure of nerve fiber tracts. It relies on the molecular diffusion of water molecules in tissues. Within neural tissues, the diffusion is anisotropic since the mobility of water molecules is limited to one specific route by biological barricades such as cellular membranes and myelin sheath. Any disruption or modification of this facilitated molecular diffusion anywhere along the neuronal path can herald a disturbance in the physiology which explains why DTI is most sensitive to initial changes, even earlier than the appearance of gross physical changes on conventional MRI sequences.[15],[16] DTI is presently the only noninvasive technique for evaluation of integrity of white matter tracts in living beings.[17],[18]

The diffusion pattern is indicated by FA which ranges from 0 to 1. Totally isotropic diffusion is indicated by a value of 0, whereas extremely anisotropic diffusion is indicated by 1. The ADC quantifies the diffusion magnitude with increased values of ADC indicating smaller amount of restriction which, in turn, implies less amount of undamaged fibers.[19]

It is imperative to know alterations in normal values of DTI regarding factors which may potentially influence them to deliver a consistent interpretation of parameters of DTI among patients. Previous studies conducted by Ellingson et al.,[3] Lindberg et al.,[20] Mamata et al.,[21] Song et al.,[22] and Vedantam et al.[23] have reported that FA decreases linearly in the rostrocaudal direction. This has been thought probably to be due to the variation in proportion of gray and white matter at different spinal levels.[24] Some differences could be due to interruption of the “directional coherence” of fibers by the exiting nerve roots of brachial plexus in the inferior cervical levels[24] and the varying diameters of axons at different spinal cord levels.[3] In our study, to overcome these variations, the measurement of DTI parameters was made using region of interests at three various anatomic sections of the spinal cord as performed by Ellingson et al. in their study.[2]

Vedantam et al.[25] concluded that there was no significant correlation between age and DTI metrics in cases <55 years of age. However, in cases ranging between 55 and 85 years, they found a linear and negative association of FA values with age. Studies reported by Mamata et al.[21] and Petersen et al.[26] showed a substantial effect of age on DTI metrics. However, other researchers have demonstrated no link among these parameters.[27],[28] Detailed evaluation of these studies showed that the age range was wider[21] and mean age higher[26] in studies showing a significant age correlation. In addition, a study reported by Lindberg et al. demonstrated a negative association of age with FA values in the lateral aspect of the cord.[20] Since our study population consisted mostly of younger individuals, we did not consider the impact of age in our study. The average age of the cases in our study was 38.85 ± 15.68 years and that of controls was 40.40 ± 12.80 years. Furthermore, the assessment of the impact of age on DTI parameters was out of the scope of our study.

Fractional anisotropy values

In recent times, FA has been proposed to be the most extensively used index of anisotropy which facilitates comparison with statistics from other studies. FA is the value which signifies the anisotropic part of diffusion and is the tendency of water molecules to diffuse in one direction and not randomly. FA is being used as anisotropy index due to its rotational invariance and good signal-to-noise ratio.[29]

In our study, we found that FA values were the most sensitive parameter of DTI for assessment of TSCI. We found that the mean FA values at injury level among cases (0.334 ± 0.155) were significantly lesser compared to controls (0.650 ± 0.165). This decrease could be due to the restriction of anisotropic diffusion in the traumatized spinal cord. Since FA values indirectly measure the extent of myelination, higher FA values indicate the integrity of spinal nerves.[10] No significant difference was observed in the mean FA values above or below the injury level in our cases as compared to controls.

Ellingson et al. also demonstrated a decrease in FA values in TSCI patients similar to our study. They could also distinguish between patients with complete or incomplete injuries with FA values. They also found that FA values measured at injury level were considerably reduced in patients with chronic TSCI, as compared to healthy controls.[2]

Czyz et al.[1] also found that FA values in cases with TSCI were considerably lower as compared to the controls (0.48 and 0.55, respectively). Similarly, Vedantam et al.[25] and Rao et al.[30] found decreased FA values in TSCI patients compared to neurologically intact volunteers (0.61 and 0.22, respectively).

Our study was also in accordance with the findings of Shanmuganathan et al. and Cheran et al. who again showed reduced FA values in patients with TSCI as compared to controls.[31],[32]

Our study did not reveal any significant difference in mean FA values above or below the injury level, which was in concordance with the findings of D'souza et al.[10] who also found the same. However, Kamble et al.[33] in their study showed that the FA values in the cord above and below injury level were significantly reduced. They concluded that, as a result of trauma, there is resultant descending as well as ascending Wallerian degeneration, and this fact leads to altered DTI metrics.

Similar findings were also found by Mohamed et al. who conducted a study on DTI in children with spinal trauma.[34] Few other studies have also demonstrated a reduction in FA values distant to the site of trauma or the lesion.[2],[35],[36],[37],[38],[39] The reason for not finding any variation in DTI metrics above or below the level of injury in our study could probably be due to the timing of the imaging which was held soon after trauma in majority of our cases, whereas other studies have followed up the patients for a longer period of time.

Due to the significant difference in the FA values at the site of trauma among patients as compared to controls, it is logical to conclude that DTI is an invaluable instrument in assessment of the spinal cord following TSCI.

Apparent diffusion coefficient values

ADC is a measure of degree of motion of molecules of water.[40] ADC declines with increasing amount of barriers to arbitrary water motion such as myelinated axons, cellular membranes, and extracellular molecules.[41]

In our study, we determined that the mean ADC value at the level of injury among cases (1.58 ± 0.52) was significantly more as compared to values in controls (1.13 ± 0.61). No significant difference was observed in mean ADC values above or below injury level among the cases and controls.

Previous studies have also shown an increase in ADC values (mean diffusivity) in patients with acute TSCI in accordance with our study.[20],[22],[42] Cheran et al.[32] have also reported higher ADC values at the site of the injury. They found ADC and FA values to be inversely related as in our study.

Our findings were also consistent with those of D'souza et al. who reported that ADC is significantly increased in patients with TSCI signifying disorganization within the spinal cord fibers. Lower ADC values indicate that the fiber tracts of the spinal cord are intact.[10]

Our findings differ from Shanmuganathan et al. who reported that ADC is significantly decreased in patients with acute TSCI and patients with spinal cord hemorrhage exhibiting the greatest decrease. This could be due to the different patient populations in their study. They included patients with hemorrhagic cord contusions, and the blood products could play a role in the ADC values hence obtained.[31]

In contrast to our study, Ellingson et al. have reported lower ADC values in the cervical cord of patients with chronic TSCI. They suggested that these low ADC values are suggestive of the fact that there is a decrease in overall diffusion magnitude away from the injury site due to restructuring of the axons and chronic widespread spinal cord degeneration, as proved in previous animal models.[2]

The substantial DTI variations at the site of injury possibly replicate the results of both the primary as well as secondary neuronal injury and the outcome of secondary neuronal degeneration. The distraction of coherent axonal architecture possibly reduces the FA values. The increased ADC values could possibly be due to the increased extracellular fluid in the damaged tissue.[42] Tsuchiya et al. have previously predicted that raised ADC values could be due to necrosis and cord edema in the early phase and myelomalacia changes in the late phase.[43]

Due to the significant difference in the ADC values at the site of trauma among patients as compared to controls, this parameter is also of great value in diagnosing and predicting the course of TSCI.

Diffusion tensor imaging parameters in patients without any signal changes on conventional magnetic resonance imaging

MRI is an ideal technique for the evaluation of acute spinal injuries because of its extremely high sensitivity in picking up injuries to the soft tissues. It is the ideal modality for assessment of the spinal cord, ligaments, disc, and soft tissues.[44],[45] The usual protocol employed for spinal trauma consists of T1W image, T2W image, and short-tau inversion recovery sequences.

Previous reports state that SCIWORA accounts for 6%–19% and 9%–14% of spinal trauma in pediatric and adult patients, respectively, and MRI is an excellent tool for evaluation of the same.[46],[47] Patients with SCIWORA who have normal MRI findings have been classified as “Spinal Cord Injury without Neuroimaging Abnormality (SCIWNA).”[48] The usefulness of “diffusion-weighted imaging (DWI)” has already been proved in clinical evaluation of SCIWNA, wherein hyperintense lesions in the spinal cord have been observed.[49] It has previously been predicted that DTI can be an indispensable imaging tool in patients with SCIWNA who do not show any signal abnormality on DWI,[50] and our study proves the same.

We found in our study that even though 12 patients did not show any spinal cord abnormality on conventional MRI, they showed reduced FA and raised ADC values. The mean FA value in these cases was 0.391, and the mean ADC value was 1.53 in these cases, which was significantly different from those of controls (mean FA value = 0.65 and mean ADC value = 1.13). This shows that DTI is of utmost importance to evaluate patients with spinal trauma, especially in those patients in whom altered signal intensity is not demonstrated on routine MRI sequences.

Therefore, we conclude that DTI shows great promise in predicting and diagnosing early cord injury even in those patients with spinal trauma who do not demonstrate any alteration in the signal intensity on conventional MRI sequences. This fact was proved in our study by the reduced FA and raised ADC values in patients with spinal trauma who showed an apparently normal spinal cord on conventional MRI as compared to the controls.


  Conclusions Top


DTI is an invaluable instrument in assessment of the spinal cord following TSCI due to the significant difference in the FA and ADC values. FA values reflect the cord functionality, whereas ADC may serve as a potential prognostic factor. We also propose that a correlation between the quantitative parameters of diffusion such as FA and ADC can be used for monitoring the response to therapy. DTI parameters can also detect subtle disruption of white matter in patients with spinal trauma and thus can have a better clinical correlation with neurological deficit. Spinal cord DTI has a very high potential in forecasting the severity of spinal injury and is of high predictive value in the prognosis of neurological recovery. Our study also shows that DTI is indispensable for diagnosing cord injury even in those patients with apparently normal cord on conventional MRI sequences.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.



 
  References Top

1.
Czyz M, Tykocki T, Szewczyk P, Jarmundowicz W. Application of diffusion tensor imaging in the prognosis of outcome after traumatic cervical spinal cord injury. J Spinal Stud Surg 2017;1:25-8.  Back to cited text no. 1
  [Full text]  
2.
Ellingson BM, Ulmer JL, Kurpad SN, Schmit BD. Diffusion tensor MR imaging in chronic spinal cord injury. AJNR Am J Neuroradiol 2008;29:1976-82.  Back to cited text no. 2
    
3.
Ellingson BM, Ulmer JL, Kurpad SN, Schmit BD. Diffusion tensor MR imaging of the neurologically intact human spinal cord. AJNR Am J Neuroradiol 2008;29:1279-84.  Back to cited text no. 3
    
4.
Virta A, Barnett A, Pierpaoli C. Visualizing and characterizing white matter fiber structure and architecture in the human pyramidal tract using diffusion tensor MRI. Magn Reson Imaging 1999;17:1121-33.  Back to cited text no. 4
    
5.
Sąsiadek MJ, Szewczyk P, Bladowska J. Application of diffusion tensor imaging (DTI) in pathological changes of the spinal cord. Med Sci Monit 2012;18:RA73-9.  Back to cited text no. 5
    
6.
Szwedowski D, Walecki J. Spinal cord injury without radiographic abnormality (SCIWORA) – Clinical and radiological aspects. Pol J Radiol 2014;79:461-4.  Back to cited text no. 6
    
7.
Silberstein M, Tress BM, Hennessy O. Prediction of neurologic outcome in acute spinal cord injury: The role of CT and MR. AJNR Am J Neuroradiol 1992;13:1597-608.  Back to cited text no. 7
    
8.
Katzberg RW, Benedetti PF, Drake CM, Ivanovic M, Levine RA, Beatty CS, et al. Acute cervical spine injuries: Prospective MR imaging assessment at a level 1 trauma center. Radiology 1999;213:203-12.  Back to cited text no. 8
    
9.
Flanders AE, Schaefer DM, Doan HT, Mishkin MM, Gonzalez CF, Northrup BE. Acute cervical spine trauma: Correlation of MR imaging findings with degree of neurologic deficit. Radiology 1990;177:25-33.  Back to cited text no. 9
    
10.
D'souza MM, Choudhary A, Poonia M, Kumar P, Khushu S. Diffusion tensor MR imaging in spinal cord injury. Injury 2017;48:880-4.  Back to cited text no. 10
    
11.
Kulkarni MV, McArdle CB, Kopanicky D, Miner M, Cotler HB, Lee KF, et al. Acute spinal cord injury: MR imaging at 1.5 T. Radiology 1987;164:837-43.  Back to cited text no. 11
    
12.
Bondurant FJ, Cotler HB, Kulkarni MV, McArdle CB, Harris JH Jr. Acute spinal cord injury. A study using physical examination and magnetic resonance imaging. Spine (Phila Pa 1976) 1990;15:161-8.  Back to cited text no. 12
    
13.
Flanders AE, Spettell CM, Tartaglino LM, Friedman DP, Herbison GJ. Forecasting motor recovery after cervical spinal cord injury: Value of MR imaging. Radiology 1996;201:649-55.  Back to cited text no. 13
    
14.
Matsumoto M, Toyama Y, Ishikawa M, Chiba K, Suzuki N, Fujimura Y. Increased signal intensity of the spinal cord on magnetic resonance images in cervical compressive myelopathy. Does it predict the outcome of conservative treatment? Spine (Phila Pa 1976) 2000;25:677-82.  Back to cited text no. 14
    
15.
Rajasekaran S, Kanna RM, Shetty AP. Diffusion tensor imaging of the spinal cord and its clinical applications. J Bone Joint Surg Br 2012;94:1024-31.  Back to cited text no. 15
    
16.
Bosma R, Stroman PW. Diffusion tensor imaging in the human spinal cord: Development, limitations, and clinical applications. Crit Rev Biomed Eng 2012;40:1-20.  Back to cited text no. 16
    
17.
Niogi SN, Mukherjee P, Ghajar J, Johnson C, Kolster RA, Sarkar R, et al. Extent of microstructural white matter injury in postconcussive syndrome correlates with impaired cognitive reaction time: A 3T diffusion tensor imaging study of mild traumatic brain injury. AJNR Am J Neuroradiol 2008;29:967-73.  Back to cited text no. 17
    
18.
Stroman PW, Wheeler-Kingshott C, Bacon M, Schwab JM, Bosma R, Brooks J, et al. The current state-of-the-art of spinal cord imaging: Methods. Neuroimage 2014;84:1070-81.  Back to cited text no. 18
    
19.
Alicata D, Chang L, Cloak C, Abe K, Ernst T. Higher diffusion in striatum and lower fractional anisotropy in white matter of methamphetamine users. Psychiatry Res 2009;174:1-8.  Back to cited text no. 19
    
20.
Lindberg PG, Feydy A, Maier MA. White matter organization in cervical spinal cord relates differently to age and control of grip force in healthy subjects. J Neurosci 2010;30:4102-9.  Back to cited text no. 20
    
21.
Mamata H, Jolesz FA, Maier SE. Apparent diffusion coefficient and fractional anisotropy in spinal cord: Age and cervical spondylosis-related changes. J Magn Reson Imaging 2005;22:38-43.  Back to cited text no. 21
    
22.
Song T, Chen WJ, Yang B, Zhao HP, Huang JW, Cai MJ, et al. Diffusion tensor imaging in the cervical spinal cord. Eur Spine J 2011;20:422-8.  Back to cited text no. 22
    
23.
Vedantam A, Jirjis M, Eckhardt G, Sharma A, Schmit BD, Wang MC, et al. Diffusion tensor imaging of the spinal cord: A review. Coluna/Columna 2013;12:64-9.  Back to cited text no. 23
    
24.
Wheeler-Kingshott CA, Cercignani M. About “axial” and “radial” diffusivities. Magn Reson Med 2009;61:1255-60.  Back to cited text no. 24
    
25.
Vedantam A, Jirjis MB, Schmit BD, Wang MC, Ulmer JL, Kurpad SN. Diffusion tensor imaging of the spinal cord: Insights from animal and human studies. Neurosurgery 2014;74:1-8.  Back to cited text no. 25
    
26.
Petersen JA, Wilm BJ, von Meyenburg J, Schubert M, Seifert B, Najafi Y, et al. Chronic cervical spinal cord injury: DTI correlates with clinical and electrophysiological measures. J Neurotrauma 2012;29:1556-66.  Back to cited text no. 26
    
27.
Cui JL, Wen CY, Hu Y, Li TH, Luk KD. Entropy-based analysis for diffusion anisotropy mapping of healthy and myelopathic spinal cord. Neuroimage 2011;54:2125-31.  Back to cited text no. 27
    
28.
Hesseltine SM, Law M, Babb J, Rad M, Lopez S, Ge Y, et al. Diffusion tensor imaging in multiple sclerosis: Assessment of regional differences in the axial plane within normal-appearing cervical spinal cord. AJNR Am J Neuroradiol 2006;27:1189-93.  Back to cited text no. 28
    
29.
Guo AC, Cummings TJ, Dash RC, Provenzale JM. Lymphomas and high-grade astrocytomas: Comparison of water diffusibility and histologic characteristics. Radiology 2002;224:177-83.  Back to cited text no. 29
    
30.
Rao JS, Zhao C, Yang ZY, Li SY, Jiang T, Fan YB, et al. Diffusion tensor tractography of residual fibers in traumatic spinal cord injury: A pilot study. J Neuroradiol 2013;40:181-6.  Back to cited text no. 30
    
31.
Shanmuganathan K, Gullapalli RP, Zhuo J, Mirvis SE. Diffusion tensor MR imaging in cervical spine trauma. AJNR Am J Neuroradiol 2008;29:655-9.  Back to cited text no. 31
    
32.
Cheran S, Shanmuganathan K, Zhuo J, Mirvis SE, Aarabi B, Alexander MT, et al. Correlation of MR diffusion tensor imaging parameters with ASIA motor scores in hemorrhagic and nonhemorrhagic acute spinal cord injury. J Neurotrauma 2011;28:1881-92.  Back to cited text no. 32
    
33.
Kamble RB, Venkataramana NK, Naik AL, Rao SV. Diffusion tensor imaging in spinal cord injury. Indian J Radiol Imaging 2011;21:221-4.  Back to cited text no. 33
[PUBMED]  [Full text]  
34.
Mohamed FB, Hunter LN, Barakat N, Liu CS, Sair H, Samdani AF, et al. Diffusion tensor imaging of the pediatric spinal cord at 1.5T: Preliminary results. AJNR Am J Neuroradiol 2011;32:339-45.  Back to cited text no. 34
    
35.
Chang Y, Jung TD, Yoo DS, Hyun JK. Diffusion tensor imaging and fiber tractography of patients with cervical spinal cord injury. J Neurotrauma 2010;27:2033-40.  Back to cited text no. 35
    
36.
Cohen-Adad J, El Mendili MM, Lehéricy S, Pradat PF, Blancho S, Rossignol S, et al. Demyelination and degeneration in the injured human spinal cord detected with diffusion and magnetization transfer MRI. Neuroimage 2011;55:1024-33.  Back to cited text no. 36
    
37.
Koskinen E, Brander A, Hakulinen U, Luoto T, Helminen M, Ylinen A, et al. Assessing the state of chronic spinal cord injury using diffusion tensor imaging. J Neurotrauma 2013;30:1587-95.  Back to cited text no. 37
    
38.
Freund P, Weiskopf N, Ward NS, Hutton C, Gall A, Ciccarelli O, et al. Disability, atrophy and cortical reorganization following spinal cord injury. Brain 2011;134:1610-22.  Back to cited text no. 38
    
39.
Ghosh A, Haiss F, Sydekum E, Schneider R, Gullo M, Wyss MT, et al. Rewiring of hindlimb corticospinal neurons after spinal cord injury. Nat Neurosci 2010;13:97-104.  Back to cited text no. 39
    
40.
Coleman WP, Geisler FH. Injury severity as primary predictor of outcome in acute spinal cord injury: Retrospective results from a large multicenter clinical trial. Spine J 2004;4:373-8.  Back to cited text no. 40
    
41.
Schwartz ED, Chin CL, Shumsky JS, Jawad AF, Brown BK, Wehrli S, et al. Apparent diffusion coefficients in spinal cord transplants and surrounding white matter correlate with degree of axonal dieback after injury in rats. AJNR Am J Neuroradiol 2005;26:7-18.  Back to cited text no. 41
    
42.
Pierpaoli C, Barnett A, Pajevic S, Chen R, Penix LR, Virta A, et al. Water diffusion changes in Wallerian degeneration and their dependence on white matter architecture. Neuroimage 2001;13:1174-85.  Back to cited text no. 42
    
43.
Tsuchiya K, Katase S, Fujikawa A, Hachiya J, Kanazawa H, Yodo K. Diffusion-weighted MRI of the cervical spinal cord using a single-shot fast spin-echo technique: Findings in normal subjects and in myelomalacia. Neuroradiology 2003;45:90-4.  Back to cited text no. 43
    
44.
Wilmink JT. MR imaging of the spine: Trauma and degenerative disease. Eur Radiol 1999;9:1259-66.  Back to cited text no. 44
    
45.
Shah LM, Ross JS. Imaging of Spine trauma. Neurosurgery 2016;79:626-42.  Back to cited text no. 45
    
46.
Eleraky MA, Theodore N, Adams M, Rekate HL, Sonntag VK. Pediatric cervical spine injuries: Report of 102 cases and review of the literature. J Neurosurg 2000;92:12-7.  Back to cited text no. 46
    
47.
Burke DC. Traumatic spinal paralysis in children. Paraplegia 1974;11:268-76.  Back to cited text no. 47
    
48.
Yucesoy K, Yuksel KZ. SCIWORA in MRI era. Clin Neurol Neurosurg 2008;110:429-33.  Back to cited text no. 48
    
49.
Shen H, Tang Y, Huang L, Yang R, Wu Y, Wang P, et al. Applications of diffusion-weighted MRI in thoracic spinal cord injury without radiographic abnormality. Int Orthop 2007;31:375-83.  Back to cited text no. 49
    
50.
Thurnher MM, Law M. Diffusion-weighted imaging, diffusion-tensor imaging, and fiber tractography of the spinal cord. Magn Reson Imagfing Clin N Am 2009;17:225-44.  Back to cited text no. 50
    


    Figures

  [Figure 1], [Figure 2], [Figure 3]
 
 
    Tables

  [Table 1], [Table 2], [Table 3], [Table 4]



 

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