title: Accuracy of visible retinal emboli for the detection of cardioembolic lesions requiring anticoagulation or cardiac surgery. Retinal Emboli of Cardiac Origin Study Group.
abstract: OBJECTIVE
  To determine the accuracy of visible retinal emboli as a diagnostic "test" for the likelihood of receiving anticoagulation or cardiac surgery based on the results of transthoracic echocardiography, in the setting of acute retinal arterial occlusion.
  
  
  METHODS
  A multicentre retrospective diagnostic study at Kingston Eye Centre, Queen's University, Kingston, Ontario; Wills Eye Hospital, Philadelphia; Ottawa Eye Institute, Ottawa, Ontario; and the Halifax Infirmary, Halifax, Nova Scotia of 104 patients with both embolic and nonembolic acute retinal arterial obstruction who underwent transthoracic echocardiography was performed, to determine the accuracy of visible retinal emboli as a diagnostic "test" for anticoagulation or cardiac surgery. Anticoagulation or surgical intervention on the basis of abnormalities was detected solely through the technology of transthoracic echocardiography.
  
  
  RESULTS
  41 patients had visible retinal emboli (calcific, cholesterol, or fibrin). The remaining 63 had no evidence of embolic disease. The sensitivity of emboli for the likelihood of a patient receiving anticoagulation or cardiac surgery was 50%. The specificity, positive predictive value, and negative predictive value were 62%, 15%, and 90%, respectively. The likelihood ratio (LR = 1.31) obtained given the presence of a visible retinal embolus was neither clinically nor statistically significant (LR+ve = 1.31; 95% CI (0.91, 3.16)). This likelihood ratio, when applied to a patient with a pretest probability of 50%, results in a post-test probability of 56.7%.
  
  
  CONCLUSIONS
  These results demonstrate that the presence of a visible retinal embolus should not be the sole determinant of whether to order transthoracic echocardiography, as the likelihood ratio for a patient receiving anticoagulation or cardiac surgery, given the presence of a visible retinal embolus was only 1.31.
authors.affiliation: Coordinating Centre, Queen's University, Kingston Ontario, Canada.
authors.forename: S
authors.initials: S
authors.lastname: Sharma
authors.forename: G C
authors.initials: GC
authors.lastname: Brown
authors.forename: A F
authors.initials: AF
authors.lastname: Cruess
mesh_terms: D000925:Anticoagulants / Q000627:therapeutic use*; D004452:Echocardiography; D004617:Embolism / Q000175:diagnosis* / Q000188:drug therapy / Q000601:surgery; D006331:Heart Diseases / Q000175:diagnosis* / Q000188:drug therapy / Q000601:surgery; D006801:Humans; D008875:Middle Aged; D018579:Patient Selection; D011237:Predictive Value of Tests; D012164:Retinal Diseases / Q000175:diagnosis*; D012171:Retinal Vessels; D012189:Retrospective Studies; D012680:Sensitivity and Specificity
chemical_list: D000925:Anticoagulants