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Updated: Sep 18, 2025
Retinal Vascular Reactivity as Assessed by Optical Coherence Tomography Angiography
Published on: March 26, 2020
Prognostic factors for acute central retinal artery occlusion treated with hyperbaric oxygen: The Hong Kong study
Sunny Chi Lik Au1,2, Steffi Shing Yee Chong1,3
1Department of Ophthalmology, Tung Wah Eastern Hospital, Hong Kong 999077, China.
Insights
Hyperbaric oxygen therapy (HBOT) can improve vision in central retinal artery occlusion (CRAO) patients. A thinner macular rim and shorter perfusion delay on angiography predict better visual outcomes in CRAO treated with HBOT.
Area of Science:
- Ophthalmology
- Retinal Vascular Diseases
- Hyperbaric Medicine
Background:
- Central retinal artery occlusion (CRAO) is a severe condition with significant vision loss potential.
- Hyperbaric oxygen therapy (HBOT) is an emerging treatment for CRAO, supported by growing evidence.
- Current acute management strategies lack a definitive gold standard treatment for CRAO.
Purpose of the Study:
- To identify key factors and imaging parameters predicting visual recovery in CRAO patients undergoing HBOT.
- To guide ophthalmologists in selecting appropriate CRAO patients for HBOT treatment.
- To establish prognostic indicators for visual outcomes in CRAO.
Main Methods:
- Prospective collection of data from CRAO patients treated with HBOT within 6 hours of symptom onset.
- Inclusion of patient demographics, onset time, ocular parameters, and medical history.
- Analysis of visual acuity (VA) improvement and correlation with imaging findings post-HBOT.
Main Results:
- Mean VA improvement of 0.48 logMAR (approx. 9 ETDRS letters) observed post-HBOT (P=0.0001).
- A 1-to-3 mm circular rim of central macular thickness (CMT) showed a fair association with VA changes (P=0.02).
- Shorter retinal perfusion delay on fundus fluorescein angiography (FFA) was moderately associated with better visual outcomes (P=0.01).
Conclusions:
- A thinner 1-to-3 mm circular rim of CMT, not the central 1 mm zone, correlates with improved visual outcomes in CRAO patients.
- Reduced perfusion delay during FFA is a significant predictor of better visual recovery.
- These findings aid in tailoring HBOT for CRAO based on specific imaging markers.
Background:
Central retinal artery occlusion (CRAO) is a potentially blinding disease, and hyperbaric oxygen therapy (HBOT) is becoming increasingly popular with the support of scientific evidence. Despite the presence of various acute management measures, there is no clear evidence on the gold standard treatment for CRAO.
Aim:
To identify factors and imaging parameters associated with good visual outcome, which guide ophthalmologists in the triage of CRAO patients for HBOT.
Methods:
Patients who suffered from CRAO and had a symptom onset ≤ 6 h were recruited for a course of HBOT in a tertiary hospital after failing bedside treatment. Patient demographics, onset time, CRAO eye parameters, and past medical history were prospectively collected. Visual outcomes after HBOT were also analyzed.
Results:
A total of 26 patients were included; the female-to-male ratio was 1:1.6, and the mean age was 67.5 years ± 13.3 years (range 44-89 years). The mean duration of follow-up and mean visual acuity (VA) improvement were 10.0 mo ± 5.3 mo and 0.48 logarithm of minimal angle of resolution (logMAR) ± 0.57 logMAR (approximately 9 letters in ETDRS) (P = 0.0001, Z = -3.67), respectively. The 1 mm zone of central macular thickness (CMT) on optical coherence tomography was not associated with VA changes (P = 0.119); however, the 1-to-3 mm circular rim of CMT was fairly associated (P = 0.02, Spearman's coefficient = 0.45). Complete retinal perfusion time during fundus fluorescein angiography (FFA) was moderately associated (P = 0.01, Spearman's coefficient = 0.58) with visual outcome.
Conclusion:
A thinner 1-to-3 mm circular rim of CMT, but not the central 1 mm zone, is associated with better visual outcome. A shorter perfusion delay on FFA is also associated with better visual outcome.
