title: Visual field defect after posterior spine fusion.
abstract: METHODS
  Case report and literature review.
  
  
  OBJECTIVE
  Review cases and literature regarding visual loss following posterior spine fusion for scoliosis and emphasize right-to-left atrial shunt as a risk factor for paradoxical embolus resulting in a postoperative visual field defect.
  
  
  BACKGROUND
  The existing literature discusses various possible etiologies of postoperative visual loss including direct pressure, hypotension, blood loss, and anemia. One study shows higher rates of cerebral microemboli in patients with right-to-left atrial shunts.
  
  
  METHODS
  Chart and literature review.
  
  
  RESULTS
  A paradoxical embolus to a branch of the central retinal artery resulted in a unilateral quadrant defect (homonymous quadrantanopsia) in a girl with a previously undiagnosed right-to-left atrial shunt.
  
  
  CONCLUSIONS
  Right-to-left atrial shunts may predispose to cerebral emboli during scoliosis surgery. These emboli may be a cause of postoperative visual field defects.
authors.affiliation: Department of Orthopaedic Surgery, Children's Hospital, Boston, Massachusetts, USA. katzdortho@aol.com
authors.forename: Danielle A
authors.initials: DA
authors.lastname: Katz
authors.forename: Lawrence I
authors.initials: LI
authors.lastname: Karlin
mesh_terms: D002648:Child; D005260:Female; D006344:Heart Septal Defects, Atrial / Q000150:complications / Q000473:pathology; D006423:Hemianopsia / Q000209:etiology* / Q000473:pathology; D006801:Humans; D020766:Intracranial Embolism / Q000473:pathology; D011183:Postoperative Complications; D012161:Retinal Artery / Q000473:pathology; D015356:Retinal Artery Occlusion / Q000150:complications / Q000473:pathology; D012600:Scoliosis / Q000150:complications / Q000601:surgery*; D013123:Spinal Fusion / Q000009:adverse effects*; D014794:Visual Fields