Efficacy and safety of hyperbaric oxygen therapy for acute central retinal artery occlusion in Hong Kong: results of the first 3 years

Purpose: To review the efficacy and safety of hyperbaric oxygen therapy (HBOT) for central retinal artery occlusion (CRAO) in Hong Kong patients. Methods: Patients diagnosed with CRAO with symptom onset ≤6 hours who failed emergency bedside ocular treatment were referred to a course of HBOT. Changes in best corrected visual acuity (VA) after HBOT and adverse effects and complications of HBOT were recorded. Changes in best corrected VA between the pre-COVID-19 group and the COVID-19-pandemic group were compared. Results: 34 men and 26 women with CRAO aged 27 to 89 years were included for analysis. The mean follow-up period was 169±226 days. The mean number of HBOT sessions received was 8.6±3.2. The mean best corrected VA improved from 2.02±0.36 to 1.53±0.61 logMAR after HBOT (p<0.00001). 65% of patients had improvement and 33.3% had no improvement. VA changes between the pre-COVID-19 group (n=22) and COVID-19-pandemic group (n=38) were comparable (-0.53±0.58 vs -0.46±0.57 logMAR, p=0.59), despite a delay in hospital attendance. 41.7% of patients failed to equalize the pressure during treatment requiring myringotomy or even grommet insertion. 20% of patients had barotrauma. Other adverse events included convulsion, confusion, sinus pain, and hypoglycemia. Conclusion: In patients with CRAO, HBOT is effective in improving best corrected VA, even during the COVID-19 pandemic.