title: Less Is More: Efficacy of Rapid 3D-T2 SPACE in ED Patients with Acute Atypical Low Back Pain.
abstract: Emergency department (ED) patients with acute low back pain (LBP) may present with ambiguous clinical findings that pose diagnostic challenges to exclude cauda equina syndrome (CES). As a proof of concept, we aimed to determine the efficacy of a rapid lumbar spine (LS) magnetic resonance imaging (MRI) screening protocol consisting of a single 3D-T2 SPACE FS (3D-T2 Sampling Perfection with Application optimized Contrasts using different flip angle Evolution fat saturated) sequence relative to conventional LS MRI to exclude emergently treatable pathologies in this complex patient population.
  
  
  
  LS MRI protocol including a sagittal 3D-T2 SPACE FS pulse sequence was added to the routine for ED patients presenting with acute atypical LBP over a 12-month period. Imaging findings were categorically scored on the 3D-T2 SPACE FS sequence and separately on the reference standard conventional LS MRI sequences. Patients' symptoms were obtained from review of the electronic medical record. Descriptive test statistics were performed.
  
  
  
  Of the 206 ED patients who obtained MRI for acute atypical LBP, 118 (43.3 ± 13.5 years of age; 61 female) were included. Specific pathologies detected on reference standard conventional MRI included disc herniation (n = 30), acute fracture (n = 3), synovial cyst (n = 3), epidural hematoma (n = 2), cerebrospinal fluid leak (n = 1), and leptomeningeal metastases (n = 1), and on multiple occasions these pathologies resulted in nerve root impingement (n = 36), severe spinal canal stenosis (n = 13), cord/conus compression (n = 2), and cord signal abnormality (n = 2). The 3D-T2 SPACE FS sequence was an effective screen for fracture (sensitivity [sens] = 100%, specificity [spec] = 100%), cord signal abnormality (sens = 100%, spec = 99%), and severe spinal canal stenosis (sens = 100%, spec = 96%), and identified cord compression not seen on reference standard. Motion artifact was not seen on the 3D-T2 SPACE FS but noted on 8.5% of conventional LS MRI.
  
  
  
  The 3D-T2 SPACE FS sequence MRI is a rapid, effective screen for emergently actionable pathologies that might be a cause of CES in ED patients presenting with acute atypical LBP. As this abbreviated, highly sensitive sequence requires a fraction of the acquisition time of conventional LS MRI, it has the potential of contributing to increased efficiencies in the radiology department and improved ED throughput.
authors.affiliation: Department of Radiology, University of Utah Health Sciences Center, 30 North 1900 East #1A071, Salt Lake City, UT 84132-2140; Department of Radiology and Imaging Sciences, Indiana University School of Medicine, Indianapolis, Indiana. Electronic address: nakoontz@iupui.edu.
authors.forename: Nicholas A
authors.initials: NA
authors.lastname: Koontz
authors.affiliation: Department of Radiology, University of Utah Health Sciences Center, 30 North 1900 East #1A071, Salt Lake City, UT 84132-2140.
authors.forename: Richard H
authors.initials: RH
authors.lastname: Wiggins
authors.affiliation: Department of Radiology, University of Utah Health Sciences Center, 30 North 1900 East #1A071, Salt Lake City, UT 84132-2140.
authors.forename: Megan K
authors.initials: MK
authors.lastname: Mills
authors.affiliation: Department of Radiology, University of Utah Health Sciences Center, 30 North 1900 East #1A071, Salt Lake City, UT 84132-2140.
authors.forename: Michael S
authors.initials: MS
authors.lastname: McLaughlin
authors.affiliation: Department of Radiology, University of Utah Health Sciences Center, 30 North 1900 East #1A071, Salt Lake City, UT 84132-2140.
authors.forename: Elaine C
authors.initials: EC
authors.lastname: Pigman
authors.affiliation: Department of Radiology, University of Utah Health Sciences Center, 30 North 1900 East #1A071, Salt Lake City, UT 84132-2140.
authors.forename: Yoshimi
authors.initials: Y
authors.lastname: Anzai
authors.affiliation: Department of Radiology, University of Utah Health Sciences Center, 30 North 1900 East #1A071, Salt Lake City, UT 84132-2140.
authors.forename: Lubdha M
authors.initials: LM
authors.lastname: Shah
mesh_terms: D059787:Acute Pain / Q000000981:diagnostic imaging / Q000209:etiology; D000328:Adult; D016477:Artifacts; D003287:Contrast Media; D004636:Emergency Service, Hospital; D005260:Female; D046748:Hematoma, Epidural, Spinal / Q000150:complications / Q000000981:diagnostic imaging; D006801:Humans; D021621:Imaging, Three-Dimensional / Q000379:methods; D007405:Intervertebral Disc Displacement / Q000150:complications / Q000000981:diagnostic imaging; D017116:Low Back Pain / Q000000981:diagnostic imaging* / Q000209:etiology; D008159:Lumbar Vertebrae / Q000000981:diagnostic imaging; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D009408:Nerve Compression Syndromes / Q000150:complications / Q000000981:diagnostic imaging*; D012680:Sensitivity and Specificity; D013117:Spinal Cord Compression / Q000150:complications / Q000000981:diagnostic imaging*; D016103:Spinal Fractures / Q000150:complications / Q000000981:diagnostic imaging*; D013130:Spinal Stenosis / Q000150:complications / Q000000981:diagnostic imaging; D013581:Synovial Cyst / Q000150:complications / Q000000981:diagnostic imaging
chemical_list: D003287:Contrast Media
keywords: 3D-T2 SPACE; Acute LBP; MRI