title: Cervical foraminal steroid injections under CT guidance: retrospective study of in situ contrast aspects in a serial of 248 cases.
abstract: OBJECTIVE
  To describe all the CT findings after in situ contrast injection just before steroid injection and to recognize the abnormal aspects associated with intravascular contamination.
  
  
  METHODS
  We retrospectively evaluated 248 cervical transforaminal steroid injections done at the university hospital in Dijon, France, in 2008-2012, to treat cervicobrachial neuralgia inadequately improved by optimal medical treatment for at least 3 weeks. Features describing the opacification patterns were recorded.
  
  
  RESULTS
  Five main nonvascular opacification patterns were identified: clumps of contrast agent outside the foramen (16 %), a crab claw pattern surrounding the ganglion (13 %), a "French" circumflex accent pattern (15 %), reflux along the needle (7 %), and facet joint capsule opacification (22 %). Concerning the situations requiring a change in needle position, intravenous injection occurred in 26 % of the patients, with a crab claw pattern in half the cases and a clump pattern in half the cases. Intraarteriolar injection was noted in two patients.
  
  
  CONCLUSIONS
  CT after in situ contrast injection ensures proper needle positioning outside the blood vessels before steroid injection. Penetration of the needle tip into a vein is very common, whereas arteriolar puncture is extremely rare.
authors.affiliation: Département de Radiologie et Imagerie Diagnostique et interventionnelle, CHU Dijon Bocage Central, Dijon, France, pierre.pottecher@gmail.com.
authors.forename: Pierre
authors.initials: P
authors.lastname: Pottecher
authors.forename: Denis
authors.initials: D
authors.lastname: Krausé
authors.forename: Lucy
authors.initials: L
authors.lastname: Di Marco
authors.forename: Romaric
authors.initials: R
authors.lastname: Loffroy
authors.forename: Louis
authors.initials: L
authors.lastname: Estivalet
authors.forename: Romain
authors.initials: R
authors.lastname: Duhal
authors.forename: Xavier
authors.initials: X
authors.lastname: Demondion
mesh_terms: D000293:Adolescent; D020968:Brachial Plexus Neuritis / Q000000981:diagnostic imaging* / Q000188:drug therapy*; D002574:Cervical Vertebrae / Q000000981:diagnostic imaging; D005260:Female; D006801:Humans; D015552:Injections, Intralesional; D008297:Male; D011843:Radiculopathy / Q000000981:diagnostic imaging* / Q000188:drug therapy*; D015641:Radiography, Interventional / Q000379:methods*; D013256:Steroids / Q000008:administration & dosage*; D014057:Tomography, X-Ray Computed / Q000379:methods; D016896:Treatment Outcome
chemical_list: D013256:Steroids