title: Evaluation of transforaminal ligaments by magnetic resonance imaging.
abstract: OBJECTIVE
  Three-part study to (1) identify and describe transforaminal ligaments (TFLs), (2) determine the best low-field-strength magnetic resonance imaging (MRI) technique for TFLs, and (3) determine the ability of low-field-strength MRI to obtain images of TFLs.
  
  
  METHODS
  Part I-descriptive anatomic study; part II-descriptive MRI study; part III-blinded comparison of diagnostic test against gold standard (MRI vs anatomic dissection).
  
  
  METHODS
  Chiropractic college gross anatomy laboratory and MRI facilities.
  
  
  METHODS
  Three anatomic specimens of male cadavers age 60 to 85 years; a fourth specimen was used for training radiologists in part III.
  
  
  METHODS
  Part I-number and size of TFLs; part II-subjective grading of highest quality MRI images; part III-specificity, sensitivity, positive predictive value, negative predictive value, percent agreement, and accuracy of identifying TFLs from MRI scans.
  
  
  RESULTS
  Part I-19 TFLs identified in 30 intervertebral foramina (IVFs) (60% of IVFs had TFLs), thick = 4 (21%), medium thickness = 12 (63.2%), thin = 3 (15.8%); part II-TFLs demonstrated to best advantage with pure sagittal plane, T(1)-weighted MRI; part III-average: specificity = 88.9%, sensitivity = 45.6%, positive predictive value = 86.7%, negative predictive value = 50.8%, percent agreement = 78%, and accuracy = 62.4%.
  
  
  CONCLUSIONS
  The number of TFLs was in general agreement with previous research. Images of TFLs can be successfully imaged with low-field-strength MRI. If a trained radiologist identifies a TFL, there is an 87% chance that one is present, and if a trained radiologist does not identify a TFL in an intervertebral foramen, there remains a 51% chance that one is present.
authors.affiliation: Department of Research, National University of Health Sciences, 200 E Roosevelt Road, Lombard, IL 60148, USA. gcramer@nuhs.edu
authors.forename: Gregory D
authors.initials: GD
authors.lastname: Cramer
authors.forename: Dennis R
authors.initials: DR
authors.lastname: Skogsbergh
authors.forename: Barclay W
authors.initials: BW
authors.lastname: Bakkum
authors.forename: James F
authors.initials: JF
authors.lastname: Winterstein
authors.forename: ShiWei
authors.initials: S
authors.lastname: Yu
authors.forename: Nathaniel R
authors.initials: NR
authors.lastname: Tuck
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D002102:Cadaver; D005069:Evaluation Studies as Topic; D006801:Humans; D008023:Ligaments, Articular / Q000473:pathology*; D008159:Lumbar Vertebrae / Q000473:pathology*; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male