1. with MR Imaging Correlation
EP - 154
Evaluation for Soft Tissue Injuries on CT in Acute Cervical Spine Trauma
with MR Imaging Correlation
Naoko Saito 1, Margaret N Chapman 2,3, Akira Uchino 1
Fumikazu Sakai 1,Osamu Sakai 3
1 Radiology, Saitama International Medical Center, Saitama Medical University
2 Radiology, Boston VA Healthcare System
3 Radiology, Boston Medical Center, Boston University School of Medicine 1

2. Introduction
Methods
Results
Discussion
Conclusion
☑ The authors have no conflict of interest to disclose with respect to this presentation. 2

3. Introduction
Methods
Results
Discussion
Conclusion
Soft tissue injuries, including ligamentous injury, muscular injury, and prevertebral edema/hematoma, are common imaging findings of cervical spine trauma.
These injuries are believed to correlate with the severity of the spinal cord injury. (Song KJ, et al. Martínez-Perez R et al. Goradia D et al.)
Although MR can clearly demonstrate these injuries, the utility of CT in their detection is often underappreciated. 3

4. Introduction
Methods
Results
Discussion
Conclusion
Purpose
To assess whether CT with soft tissue window can help identify soft tissue injuries
To compare CT with MR imaging findings in patients with acute cervical spine trauma 4

5. Subjects Retrospective imaging review
Introduction
Methods
Results
Discussion
Conclusion
Subjects
Retrospective imaging review
From January 2010 to November 2014
Patients who underwent both CT and MR imaging of cervical spine for acute traumatic spinal injury were identified
Medical records were reviewed for demographics and admitting diagnosis
The indication for MRI at our institution
Neck pain, midline cervical pain
Neurological deficits on examination
Subjective neurological complaints
Altered mental status 5

6. Imaging techniques CT imaging MR imaging
Introduction
Methods
Results
Discussion
Conclusion
Imaging techniques
CT imaging
64-slice MDCT (LightSpeed VCT, GE Healthcare)
Reviewed in bone (WL/WW: 350/1500) and soft tissue (WL/WW: 55/450) windows
MR imaging
1.5 MRI (MAGNETOM Avanto, SIEMENS)
Reviewed in T1, T2-weighted, and STIR images
Sagittal T1 weighted image: TR/TE 550/10
Sagittal T2 weighted image: TR/TE 3500/85
Sagittal STIR： TR/TE 5000/60, TI 170
Axial gradient-recalled image: TR/TE 500/24, FA 30° 6

7. Introduction
Methods
Results
Discussion
Conclusion
Image analysis
Images were reviewed by a single observer with special attention directed toward soft tissue changes CT
Fracture
Dislocation
Soft tissue abnormality
Interspinous soft tissue
Supraspinous soft tissue
Prevertebral soft tissue
Posterior cervical musculature
MRI
Fracture
Dislocation
Soft tissue abnormality
Interspinous soft tissue
Supraspinous soft tissue
Prevertebral soft tissue
Posterior cervical musculature
Spinal cord abnormality 7

8. Evaluation for soft tissue injury: sagittal
Introduction
Methods
Results
Discussion
Conclusion
Evaluation for soft tissue injury: sagittal CT
soft tissue window
STIR
A 74-year-old man with interspinous (arrows) and supraspinous (arrows) soft tissue injuries and prevertebral edema (arrowheads). 8

9. Evaluation for soft tissue injury: axial
Introduction
Methods
Results
Discussion
Conclusion
Evaluation for soft tissue injury: axial
CT soft tissue window
T2*
A 74-year-old man with interspinous (arrows) and supraspinous (arrows) soft tissue injuries and prevertebral edema (arrowheads). 9

10. Patient characteristics
Introduction
Methods
Results
Discussion
Conclusion
Patient characteristics
157 patients with acute cervical spine trauma were identified during the 5-year period
Age: (avg. 59.5) years old
Gender: 34 women, 123 men
Mechanism: Fall 108, MVC/MCA 45, others 4
MVC = motor vehicle collision, MCA = motorcycle accident
Days between CT and MR: (avg. 1.2) days 10

11. Patient characteristics
Introduction
Methods
Results
Discussion
Conclusion
Patient characteristics
157 patients with acute cervical spine trauma were identified during the 5-year period
Fracture 52 patients
MR imaging abnormality
Spinal cord injury 83 patients
Paraspinal soft tissue injury 92 patients 11

12. Soft tissue abnormalities
Introduction
Methods
Results
Discussion
Conclusion
Soft tissue abnormalities
Out of 157 patients,
59 patients (37.6%) showed abnormalities in the paraspinal soft tissues on CT
92 patients (58.6%) showed abnormalities in the paraspinal soft tissues on MR imaging
Of 92 patients with paraspinal soft tissue injuries by MR,
CT identified the abnormalities in 57 patients (62.0%) 12

13. Soft tissue abnormalities
Introduction
Methods
Results
Discussion
Conclusion
Soft tissue abnormalities
Of 59 patients with paraspinal soft tissue abnormalities on CT,
38 patients (64.4%) demonstrated the abnormalities adjacent to the fractures
18 patients (15.3%) showed prevertebral edema
Of 18 patients with prevertebral edema on CT,
12 patients (66.7%) had cervical spine fractures 13

14. Soft tissue injury with spinal cord injury
Introduction
Methods
Results
Discussion
Conclusion
Soft tissue injury with spinal cord injury
Of 59 patients with paraspinal soft tissue abnormalities on CT,
37 patients (62.7%) had spinal cord signal abnormalities on MR imaging
11 patients (18.6%) did not have fracture or dislocation but had spinal cord abnormalities on MR imaging
Of 18 patients with prevertebral edema on CT,
13 patients (72.2%) had spinal cord injury on MR imaging 14

15. Soft tissue injury with spinal cord injury
Introduction
Methods
Results
Discussion
Conclusion
Soft tissue injury with spinal cord injury
Paraspinal soft tissue injury
Prevertebral edema
+ CT findings 59 18
Cord signal abnormality on MRI 37 13
Odds Ratio
1.9 (95% CI 0.9 to 3.7)
2.6 (95% CI 0.9 to 7.6) 15

16. Introduction
Methods
Results
Discussion
Conclusion
Representative case 1
Soft tissue injury with fracture and spinal cord injury. A 75-year-old man after a fall from 16 stairs presented with lost of consciousness.
STIR
There is a posterior spinous process fracture of C4 (arrows). CT with soft tissue window shows fat stranding within the intraspinous soft tissues (arrow) adjacent the to fracture. STIR image demonstrates intra- and supraspinous soft tissues injuries (arrows) and spinal cord injury with hemorrhage at the level of C4/5 (arrow). 16

17. Introduction
Methods
Results
Discussion
Conclusion
Representative case 2
Prevertebral edema with spinal cord injury. A 73-year-old woman after a fall from standing presented with quadriplegia.
STIR
There is no fracture on CT. CT with soft tissue window shows prevertebral edema (arrowheads) and fat stranding within the intra- and supraspinous (arrows) soft tissues, correlating with STIR image. Spinal cord injury at the level of C2-5 is seen (arrow). 17

18. Evaluation for soft tissue injuries in acute cervical spine trauma
Introduction
Methods
Results
Discussion
Conclusion
Evaluation for soft tissue injuries in acute cervical spine trauma
Soft tissue injuries are believed to correlate with the severity of the spinal cord injury
Could be useful in predicting neurologic outcome (Song KJ, et al. Martínez-Perez R et al. Goradia D et al.)
Ligamentous injury: anterior longitudinal ligaments, posterior longitudinal ligaments, and ligamentum flavum
MR imaging has been reported as clearly superior to CT in detecting soft tissue injuries
Utility of CT in their detection is often underappreciated 18

19. Evaluation for soft tissue injuries on CT
Introduction
Methods
Results
Discussion
Conclusion
Evaluation for soft tissue injuries on CT
CT identified approximately 2/3 of the soft tissue abnormalities observed on MR imaging
CT findings of soft tissue abnormality:
Fat stranding within the interspinous and supraspinous regions
Posterior cervical musculature swelling
Prevertebral soft tissue swelling
These CT findings may be associated with ligamentous injuries
Soft tissue abnormalities were often seen adjacent to the fractures on CT
Evaluation with soft tissue window could help to detect subtle fractures 19

20. Evaluation for soft tissue injuries on CT
Introduction
Methods
Results
Discussion
Conclusion
Evaluation for soft tissue injuries on CT
About 60% of the patients with paraspinal soft tissue abnormality on CT had spinal cord injury on MR imaging
Furthermore, approximately 20% of those patients did not have fracture or dislocation
Evaluation of paraspinal soft tissue abnormality on CT could also be useful in predicting neurologic outcome 20

21. Prevertebral edema/hematoma
Introduction
Methods
Results
Discussion
Conclusion
Patients with prevertebral edema on CT were more likely to have spinal cord injury
Prevertebral edema is thought to be associated with more severe cervical spine trauma
Prevertebral edema/hematoma
Occurred mainly in hyperextension and whiplash injuries (Hutter G et al.)
Disruption of the anterior ligaments
Fractures of the anterior bony elements
Occurred in the elderly or anticoagulated patients (Hutter G et al.)
Caused by high-energy trauma in younger patients (Kuhn JE et al.) 21

22. Evaluation for soft tissue on CT Retrospective nature
Introduction
Methods
Results
Discussion
Conclusion
Limitations
Evaluation for soft tissue on CT
Beam hardening artifacts
Retrospective nature
Time difference between CT and MR examinations
Sampling bias
A single observer
Correlation of surgical findings or clinical outcome
Future study 22

23. Introduction
Methods
Results
Discussion
Conclusion
Conclusion
Although MR imaging is highly sensitive for detecting ligamentous and paraspinal soft tissue injuries, CT with soft tissue window can also demonstrate paraspinal soft tissue abnormalities in patients with acute cervical spine injury.
Patients with soft tissue abnormalities, especially prevertebral edema on CT, are 3 times more likely to have spinal cord injuries. 23

24. References Thank you! Introduction Methods Results Discussion
Conclusion
References
Martínez-Perez R, Paredes I, Cepeda S, et al. Spinal Cord Injury after Blunt Cervical Spine Trauma: Correlation of Soft-Tissue Damage and Extension of Lesion. AJNR Am J Neuroradiol. 2014;35:
Hutter G, Benz R, Taub E, et al. Extensive cervical prevertebral hemorrhage with airway obstruction after low-energy hyperextension injury. Injury Extra 2014;45:53-55.
Tan LA, Kasliwal MK, Traynelis VC. Comparison of CT and MRI findings for cervical spine clearance in obtunded patients without high impact trauma. Clin Neurol Neurosurg 2014;120: 23–26.
Song KJ, Kim GH, Lee KB. The efficacy of the modified classification system of soft tissue injury in extension injury of the lower cervical spine. Spine 2008;33:E488–93.
Goradia D, Linnau KF, Cohen WA, et al. Correlation of MR Imaging Findings with Intraoperative Findings after Cervical Spine Trauma. AJNR Am J Neuroradiol. 2007;28:
Kuhn JE, Graziano GP. Airway compromise as a result of retropharyngeal hematoma following cervical spine injury. J Spinal Disord 1991;4:264-9.
Thank you! 24