title: Adverse central nervous system sequelae after selective transforaminal block: the role of corticosteroids.
abstract: BACKGROUND
  Selective transforaminal epidural injections are frequently employed in the treatment of pain emanating from the spine. Complication rates are typically low and include paresthesia, hematoma, epidural abscess, meningitis, arachnoiditis and inadvertent subdural or subarachnoid injection. Persistent paraplegia after lumbar transforaminal block has been recently reported. Undetected intra-arterial injection has been implicated as a possible cause.
  
  
  OBJECTIVE
  We present a case of massive cerebellar infarction after uneventful selective cervical transforaminal block. Intra-arterial injection of corticosteroid is implicated with focus on particulate size of compound versus blood vessel dimension. Light microscopic data are presented to confirm the potential for embolic vascular occlusion.
  
  
  METHODS
  Case report; light microscopic data.
  
  
  METHODS
  A patient underwent selective transforaminal block on the right at the C5-C6 level. There was C5-C6 disc herniation documented by magnetic resonance imaging and C6 radiculopathy by electromyographic studies.
  
  
  METHODS
  Patient follow-up from medical office records.
  
  
  METHODS
  Needle placement at the C5-C6 foramen on the right was confirmed by biplanar fluoroscopy and injection of contrast medium. Frequent heme-negative aspirations were documented.
  
  
  RESULTS
  In this patient, quadriparesis ensued shortly after injection of corticosteroid solution. The patient was admitted to the neurosurgical intensive care unit and ultimately underwent brainstem decompressive surgery when focal neurologic deficits became evident. Working diagnosis was massive cerebellar infarct. Light microscopic data are presented to illustrate particulate size in corticosteroid solutions and potential for embolic microvascular occlusion. Corticosteroid suspensions (and to a lesser extent solutions) contain large particles capable of occluding metarterioles and arterioles.
  
  
  CONCLUSIONS
  We present a case of quadriparesis and brainstem herniation after selective cervical transforaminal block. We propose a potential role for corticosteroid particulate embolus during unintended intra-arterial injection as a potential mechanism.
authors.affiliation: New York Pain Center, 7209 Buckley Road, Suite 2R, Liverpool, NY 13088, USA. northpain@cnymail.com
authors.forename: Robert L
authors.initials: RL
authors.lastname: Tiso
authors.forename: Thomas
authors.initials: T
authors.lastname: Cutler
authors.forename: Joseph A
authors.initials: JA
authors.lastname: Catania
authors.forename: Karen
authors.initials: K
authors.lastname: Whalen
mesh_terms: D000305:Adrenal Cortex Hormones / Q000009:adverse effects* / Q000627:therapeutic use; D002544:Cerebral Infarction / Q000139:chemically induced* / Q000601:surgery; D002574:Cervical Vertebrae; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007268:Injections, Epidural / Q000009:adverse effects* / Q000379:methods; D008875:Middle Aged; D009407:Nerve Block / Q000009:adverse effects* / Q000379:methods; D018570:Risk Assessment; D012720:Severity of Illness Index
chemical_list: D000305:Adrenal Cortex Hormones