Hyperbaric oxygen therapy for central retinal artery occlusion: Presenting visual acuity and time to treatment as factors associated with visual recovery

Purpose: To evaluate the effectiveness of hyperbaric oxygen (HBO2) therapy as a treatment for central retinal artery occlusion (CRAO). Methods: A total of 38 patients who underwent HBO2 for non-arteritic CRAO were identified. Patients with arteritic CRAO, branch retinal artery occlusion, ophthalmic artery occlusion, and other diagnoses were excluded from the analysis. The main outcome measured was the change in visual acuity at the most recent follow-up exam compared to the visual acuity at presentation before the initiation of HBO2 therapy. Results: The overall visual acuity after HBO2 compared with the visual acuity at presentation showed a mean improvement of 0.5 logMAR from 2.2 to 1.7 logMAR (p=0.0003). Patients who presented with hand motion and light perception vision had a mean improvement of 0.4 logMAR (p=0.058) and 0.8 logMAR (p=0.004) after HBO2, respectively. An average visual acuity improvement of 0.5 logMAR (p=0.012) was observed when patients underwent HBO2 earlier than 24 hours of symptom onset. This mean improvement increased to 0.9 logMAR (p=0.009) if HBO2 was initiated within eight hours. Conclusions: HBO2 may be an effective treatment for non-arteritic CRAO, especially if patients are treated early and present with salvageable vision. The time to treatment and the presenting visual acuity may be predictive factors on the visual prognosis following HBO2. Further studies with a prospective design and more patients are necessary to determine the long-term outcomes and the optimal protocol for HBO2 in CRAO patients.