Feasibility of identifying acute traumatic vertebral body fractures on routine Spectral CT imaging

Introduction: Spectral CT offers superior material differentiation compared to conventional CT and has increasing clinical applications, including identifying bone marrow edema(BME) to characterize vertebral body fracture(VBF) acuity. Patients presenting with suspected traumatic spine injury routinely undergo CT imaging to identify any fractures. As the management of traumatic VBF largely depends on chronicity, MRI is utilized to assess for BME and identify acuity. The adjunct of MRI is expensive, cumbersome, and contraindicated in an increasing number of patients who have implants/devices that preclude them from MRI in an acute setting. While prior studies have begun to assess the utility of dual-energy CT for the identification of BME the goal of this study is to observe the feasibility of determining the acuity of traumatic VBF utilizing routine imaging obtained on the Spectral CT scanner.

Methods: A retrospective review was performed of patients who presented to a Level 1 trauma center with acute traumatic VBF scanned on a Spectral CT scanner(Philips IQon,Philips Healthcare,Best,Netherlands) with a corresponding MRI within 3 months. Spectral images were post-processed and analyzed utilizing Philips IntelliSpace Portal - Spectral CT Viewer module with a calcium suppression index of 80 and a slice thickness of 2.0-2.5 mm. Post-processed images were evaluated for suggestion of BME and compared to the corresponding MRI. Sensitivity, specificity, and accuracy of Spectral CT for the assessment of VBF acuity were computed.

Results: A total of 59 VBF were identified in 40 patients, including 44 acute and 15 chronic confirmed on MRI. Of these, 40 acute fractures were correctly classified on spectral imaging. The sensitivity, specificity, and accuracy for identifying acute VBF were 90.9%, 86.7%, and 89.8%, respectively. Calcium suppression failed to correctly identify the acute fracture in one patient with osteopenia.

Conclusion : Routine Spectral CT imaging may allow identification of acute traumatic VBF with comparable accuracy to standard MRI. This may be particularly helpful in the management of patients with VBF who cannot acutely obtain an MRI in the setting of trauma. Future investigation is necessary to validate the utility of Spectral CT for this purpose, including blinded and prospective studies with larger sample sizes.