title: Ultrasound-guided lumbar transforaminal injections: feasibility and validation study.
abstract: METHODS
  Preclinical feasibility study.
  
  
  OBJECTIVE
  Evaluation and validation of ultrasound-guided lumbar transforaminal injections.
  
  
  BACKGROUND
  Lumbar transforaminal injections are routinely implemented in the interventional management of spinal radicular pain. Typically, these injections are administered under fluoroscopy or computed tomography. Although radiological guidance provides anatomical precision and accuracy, it is associated with radiation exposure and cannot be performed during outpatient visits or at bedside. Ultrasound-guided techniques have been previously described; however, the methodological generalizability remained unknown and validation against routine fluoroscopy has never been conducted on multiple spinal levels.
  
  
  METHODS
  We addressed the procedural accuracy of ultrasound-guided lumbar transforaminal injections and proposed anatomically sound approach. Fluoroscopic validation was performed.
  
  
  RESULTS
  Of the 50 planned injections, 46 procedures were performed. L5/S1 foraminal access was impossible in 4 cases (8%). Fluoroscopy confirmed the correct foraminal placement in all 46 injections (100%). The contrast-spread pattern was intraforaminal in 42 cases (91.3%) and extraforaminal (nerve root) in 4 cases (8.7%). When intraforaminal pattern was detected on anteroposterior image, lateral fluoroscopy demonstrated ventral epidural flow in all occasions. In 3 cases, intravascular injection was detected (6.5%).
  
  
  CONCLUSIONS
  Ultrasound-guided lumbar transforaminal injections are accurate and feasible in the preclinical setting.
authors.affiliation: University of Washington, Anesthesiology & Pain Medicine and Neurological Surgery, Seattle, WA 98105, USA. gofeld@uw.edu
authors.forename: Michael
authors.initials: M
authors.lastname: Gofeld
authors.forename: Sandee J
authors.initials: SJ
authors.lastname: Bristow
authors.forename: Sheila C
authors.initials: SC
authors.lastname: Chiu
authors.forename: Carlton K
authors.initials: CK
authors.lastname: McQueen
authors.forename: Laurent
authors.initials: L
authors.lastname: Bollag
mesh_terms: D000369:Aged, 80 and over; D059925:Anatomic Landmarks; D002102:Cadaver; D003287:Contrast Media / Q000008:administration & dosage*; D005240:Feasibility Studies; D005260:Female; D005471:Fluoroscopy; D006801:Humans; D007278:Injections, Spinal; D007472:Iohexol / Q000008:administration & dosage*; D008159:Lumbar Vertebrae / Q000000981:diagnostic imaging*; D008297:Male; D015203:Reproducibility of Results; D012447:Sacrum / Q000000981:diagnostic imaging*; D018084:Ultrasonography, Interventional
chemical_list: D003287:Contrast Media; D007472:Iohexol