title: Multidimensional Analysis of Magnetic Resonance Imaging Predicts Early Impairment in Thoracic and Thoracolumbar Spinal Cord Injury.
abstract: Literature examining magnetic resonance imaging (MRI) in acute spinal cord injury (SCI) has focused on cervical SCI. Reproducible systems have been developed for MRI-based grading; however, it is unclear how they apply to thoracic SCI. Our hypothesis is that MRI measures will group as coherent multivariate principal component (PC) ensembles, and that distinct PCs and individual variables will show discriminant validity for predicting early impairment in thoracic SCI. We undertook a retrospective cohort study of 25 patients with acute thoracic SCI who underwent MRI on admission and had American Spinal Injury Association Impairment Scale (AIS) assessment at hospital discharge. Imaging variables of axial grade, sagittal grade, length of injury, thoracolumbar injury classification system (TLICS), maximum canal compromise (MCC), and maximum spinal cord compression (MSCC) were collected. We performed an analytical workflow to detect multivariate PC patterns followed by explicit hypothesis testing to predict AIS at discharge. All imaging variables loaded positively on PC1 (64.3% of variance), which was highly related to AIS at discharge. MCC, MSCC, and TLICS also loaded positively on PC2 (22.7% of variance), while variables concerning cord signal abnormality loaded negatively on PC2. PC2 was highly related to the patient undergoing surgical decompression. Variables of signal abnormality were all negatively correlated with AIS at discharge with the highest level of correlation for axial grade as assessed with the Brain and Spinal Injury Center (BASIC) score. A multiple variable model identified BASIC as the only statistically significant predictor of AIS at discharge, signifying that BASIC best captured the variance in AIS within our study population. Our study provides evidence of convergent validity, construct validity, and clinical predictive validity for the sampled MRI measures of SCI when applied in acute thoracic and thoracolumbar SCI.
authors.affiliation: 1 Department of Radiology and Biomedical Imaging, University of California San Francisco and San Francisco General Hospital , San Francisco, California.
authors.forename: Marc C
authors.initials: MC
authors.lastname: Mabray
authors.affiliation: 1 Department of Radiology and Biomedical Imaging, University of California San Francisco and San Francisco General Hospital , San Francisco, California.|5 Brain and Spinal Injury Center, San Francisco General Hospital , San Francisco, California.
authors.forename: Jason F
authors.initials: JF
authors.lastname: Talbott
authors.affiliation: 2 Department of Emergency Medicine, University of California San Francisco and San Francisco General Hospital , San Francisco, California.|5 Brain and Spinal Injury Center, San Francisco General Hospital , San Francisco, California.
authors.forename: William D
authors.initials: WD
authors.lastname: Whetstone
authors.affiliation: 3 Department of Neurological Surgery, University of California San Francisco and San Francisco General Hospital , San Francisco, California.|5 Brain and Spinal Injury Center, San Francisco General Hospital , San Francisco, California.
authors.forename: Sanjay S
authors.initials: SS
authors.lastname: Dhall
authors.affiliation: 3 Department of Neurological Surgery, University of California San Francisco and San Francisco General Hospital , San Francisco, California.|5 Brain and Spinal Injury Center, San Francisco General Hospital , San Francisco, California.
authors.forename: David B
authors.initials: DB
authors.lastname: Phillips
authors.affiliation: 4 Department of Anesthesia and Perioperative Care, University of California San Francisco and San Francisco General Hospital , San Francisco, California.|5 Brain and Spinal Injury Center, San Francisco General Hospital , San Francisco, California.
authors.forename: Jonathan Z
authors.initials: JZ
authors.lastname: Pan
authors.affiliation: 3 Department of Neurological Surgery, University of California San Francisco and San Francisco General Hospital , San Francisco, California.|5 Brain and Spinal Injury Center, San Francisco General Hospital , San Francisco, California.
authors.forename: Geoffrey T
authors.initials: GT
authors.lastname: Manley
authors.affiliation: 3 Department of Neurological Surgery, University of California San Francisco and San Francisco General Hospital , San Francisco, California.|5 Brain and Spinal Injury Center, San Francisco General Hospital , San Francisco, California.
authors.forename: Jacqueline C
authors.initials: JC
authors.lastname: Bresnahan
authors.affiliation: 3 Department of Neurological Surgery, University of California San Francisco and San Francisco General Hospital , San Francisco, California.|5 Brain and Spinal Injury Center, San Francisco General Hospital , San Francisco, California.
authors.forename: Michael S
authors.initials: MS
authors.lastname: Beattie
authors.affiliation: 3 Department of Neurological Surgery, University of California San Francisco and San Francisco General Hospital , San Francisco, California.|5 Brain and Spinal Injury Center, San Francisco General Hospital , San Francisco, California.
authors.forename: Jenny
authors.initials: J
authors.lastname: Haefeli
authors.affiliation: 3 Department of Neurological Surgery, University of California San Francisco and San Francisco General Hospital , San Francisco, California.|5 Brain and Spinal Injury Center, San Francisco General Hospital , San Francisco, California.|6 San Francisco Veteran's Affairs Medical Center, San Francisco, California.
authors.forename: Adam R
authors.initials: AR
authors.lastname: Ferguson
mesh_terms: D000328:Adult; D005260:Female; D006801:Humans; D008159:Lumbar Vertebrae; D008279:Magnetic Resonance Imaging / Q000379:methods* / Q000592:standards; D008297:Male; D008875:Middle Aged; D025341:Principal Component Analysis; D011379:Prognosis; D015203:Reproducibility of Results; D012720:Severity of Illness Index; D013119:Spinal Cord Injuries / Q000000981:diagnostic imaging* / Q000503:physiopathology*; D013904:Thoracic Vertebrae; D055815:Young Adult
keywords: BASIC; MRI; T2 hyperintensity; TLICS; spinal cord injury; thoracic