Characterising a UK cohort with retinal ischaemic events

Objective: Retinal ischaemic events (RIE), consisting of central retinal artery occlusions (CRAO), branch retinal artery occlusion (BRAO), and amaurosis fugax (Amfug), are commonly observed in older adults, often manifesting as sudden painless monocular visual loss. CRAO and BRAO are regarded as minor strokes, while Amfug is likened to a cerebral TIA. We present an RIE patient cohort, their clinical characteristics, and outcomes as a first step in evaluating our patient outcomes, service provision, and potentially highlighting areas for improvement.

Design and method: This study is a retrospective consecutive case series from a major stroke centre in the UK: Royal Sussex County Hospital, Brighton. The electronic patient records of the stroke department were reviewed to identify all patients between August 2018 and December 2021 who had been managed following a diagnosis of RIE. Descriptive and inferential statistics were conducted on detailed clinical and demographic data of study participants, exploring their frequency distributions and testing associations between the three groups of RIE.

Results: One hundred and eleven (111) study participants with RIE were identified from the stroke register, with 56.8% (n=63) diagnosed with amaurosis fugax, 25.2% (n=28) with BRAO, and 18.0% (n=20) with CRAO. Mean age was 70.6 ± 1.2 years (SEM) and 35.1% (n=39) were female. Characteristics such as blood pressure, total cholesterol, glucose and inflammatory markers (ESR and CRP) were noted to be higher in CRAO and BRAO compared to Amfug, though not statistically significant (p>0.05). Similarly, 97%(n=195) carotid doppler scans showed greater or equal stenosis ipsilateral to the RIE, with calculated Fazeka scores showing 1.2 ± 0.1 (SEM) (n=49). Outcomes post RIE demonstrated 6.8% mortality within one year of RIE diagnosis and 14.3% of this attributable to ischaemic stroke.

Conclusions: Our cohort demonstrates that RIE is largely a large vessel disease as depicted in the risk factors identified and scores from carotid doppler and Fazeka. With RIE showing similar risk factors as that for strokes, it is essential that patients presenting with RIE should have their risk factors strictly addressed to reduce complications, morbidity and mortality associated with RIE as in all large vessel diseases.