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Background/Objectives: Imaging technology is an important part of the diagnosis and management of spinal trauma. Indications and findings in post-traumatic imaging of the vertebral column and spinal cord are reviewed. Methods: An extensive literature review was performed on the imaging of vertebral and spinal cord injury. Relevant images from a Level I trauma center were included as examples. Results: Imaging plays an important role in the evaluation of acute and chronic spinal injury. Spinal cord and soft-tissue injuries are best evaluated by magnetic resonance imaging (MRI), whereas spinal fractures are better characterized by computed tomography (CT). Vascular injuries can be evaluated using CT or MR angiography. Conclusions: Imaging using CT and MRI is essential in the management of spinal cord injuries, both in the acute and in the chronic settings. MRI shows the status of ligamentous integrity and visualizes internal derangement of the spinal cord. Vascular compromise can be diagnosed by MR and CT angiography. Plain radiography now has a more limited, adjunctive role, and the need for higher risk myelography has been minimized.

Purpose The purpose of this study was to compare and correlate standardized uptake values (SUV) derived from magnetic resonance attenuation correction (MRAC) with those derived from computed tomography attenuation correction (CTAC) in an oncology patient population. Procedures The HIPAA-compliant study was approved by the Internal Review Board and all subjects gave written informed consent prior to inclusion in the study. Forty patients (mean age 61±15.1; 20 male) referred for clinically indicated 2-deoxy-2-[18F]fluoro-D-glucose (FDG) positron emission tomography/computed tomography (PET/CT) scans also underwent a PET/magnetic resonance imaging (MRI) examination. MRAC was performed using an automatic three-segment model. Regions of interest were drawn over eight normal structures in order to obtain SUVmax and SUVmean values. Spearman rank correlation coefficients (r) were calculated and two-tailed paired t tests were performed to compare the SUVmax and SUVmean values obtained from CTAC with those from MRAC. Results The mean time after FDG injection was 66±7 min for PET/CT and 117±15 min for PET/MRI examination. MRAC SUV values were significantly lower than the CTAC SUV values in mediastinal blood pool (p<0.001 for both SUVmax and SUVmean) and liver (p=0.01 for SUVmean). The MRAC SUV values were significantly higher in bone marrow (p<0.001 for both SUVmax and SUVmean), psoas major muscle (p<0.001 for SUVmax), and left ventricular myocardium (p<0.001 for SUVmax and p=0.01 for SUVmean). For the other normal structures, no significant difference was observed. When comparing SUV values generated from CTAC versus MRAC, high correlations between CTAC and MRAC were observed in myocardium (r=0.96/ 0.97 for SUVmax/mean), liver (r=0.68 for SUVmax), bone marrow (r=0.80/0.83 for SUVmax/mean), lung tissue (r=0.70 for SUVmax), and mediastinal blood pool (r=0.0.68/.069 for SUVmax/mean). Moderate correlations were found in lung tissue (r=0.67 for SUV mean), liver (r=0.66 for SUVmean), fat (r=0.48/0.53 for SUVmax/mean), psoas major muscle (r=0.54/0.58 for SUVmax/mean), and iliacus muscle (r=0.41 for SUVmax). Low correlation was found in iliacus muscle (r=0.32 for SUVmean). Conclusions Using the automatic three-segment model, our study showed high correlation for measurement of SUV values obtained from MRAC compared to those from CTAC, as the reference standard. Differences observed between MRAC and CTAC derived SUV values may be attributed to the time-delay between the PET/CT and PET/MRI scans or biologic clearance of radiotracer. Further studies are required to assess SUV measurements when performing different MR attenuation correction techniques.