EFFICACY OF ANTERIOR-CHAMBER PARACENTESIS AND CARBOGEN IN TREATING ACUTE NONARTERITIC CENTRAL RETINAL ARTERY-OCCLUSION

Purpose: To determine whether anterior chamber paracentesis and Carbog en inhalation therapy (95% oxygen, 5% carbon dioxide) produce a signif icant difference in final Visual acuity in eyes with acute nonarteriti c central retinal artery occlusion (CRAO), compared with untreated eye s. Methods: in this retrospective study, the records of 89 consecutive patients seen at the Retina Vascular Unit of Wills Eye Hospital with acute CRAO who received either both anterior chamber paracentesis and Carbogen therapy, or neither anterior chamber paracentesis or Carbogen therapy, were reviewed. Forty patients were treated with both therapi es, whereas 49 received neither modality. Visual acuities before treat ment and at subsequent follow-up visits were measured. All patients se en within 24 hours of the onset of symptoms were treated, whereas most of those seen after 24 hours were not treated, Results: Stratified Wi lcoxon analysis showed no statistically significant difference between the treated and untreated groups (P = 0.87) after adjusting for initi al vision. A posthoc power analysis for the difference between two pro portions showed that the study had adequate power (0.80) to detect a d ifference of the proportion of improved patients of 10% versus 25% bet ween the treated and untreated groups. Conclusion: The data suggest th at anterior chamber paracentesis and Carbogen therapy offer little ben efit for treating acute nonarteritic CRAO.