New research published in Ophthalmology details a novel protocol developed by experts at the New York Eye and Ear Infirmary (NYEE) of Mount Sinai designed to rapidly diagnose and treat retinal artery occlusions (RAOs).
Give me some background.
First and foremost: RAOs are better known as “eye strokes” to the general public.
Symptoms can include sudden, painless visual acuity (VA) loss within just seconds.
In this condition, retinal blood flow is blocked, limiting oxygen delivery to the retina and, as a result, causing severe vision loss in the area of retinal ischemia.
RAO patients require immediate medical attention that typically includes an evaluation and transfer to a stroke center for potential treatment.
Gotcha. Now explain this study.
Investigators used optical coherence tomography (OCT) machines positioned in the stroke center or emergency department of three hospital locations within the Mount Sinai health system for 18 months.
The participants: 59 adult patients presenting with painless monocular vision loss and who were diagnosed with nonarteritic RAO.
How were these patients evaluated?
Each patient was examined by the hospital’s stroke neurology service via OCT; high-resolution retinal images were then interpreted and diagnosed remotely by a team of on-call retina specialists.
If the specialists confirmed a diagnosis, the vascular interventional neuroradiologists could then dissolve the clot via an infusion of tissue plasminogen activator (tPA)—a clot-dissolving therapeutic—into the patient’s blocked ophthalmic artery.
What was measured?
- VA both pre- and post-treatment (intra-arterial [IA]- tPA)
- Time from last known well (LKW) to treatment
- Time from presentation to treatment
And how long did this take, from start to finish?
The investigators reported that, on average, time to treatment (from hospital arrival) was an estimated 2.5 hours.
From the onset of symptoms, patient treatment was roughly 9 hours (including the time to arrive at hospital).
So how many patients were diagnosed?
A total of 25 patients (42%) were diagnosed with RAO based on the OCT imaging findings and remote consultation follow-up.
Of those, 10 patients were eligible for treatment and nine were treated with an infusion of tPA.
What was the resulting data?
The investigators noted a statistically significant improvement in mean VA from:
- First 24 hours after treatment (P = 0.0001)
- Logarithm of the minimum angle of resolution (logMAR) 2.14 to logMAR 0.7 (Snellen equivalent of 20/2760 to 20/100)
- After 4 weeks (P = 0.01)
- logMAR 1.04 (20/219)
Also within 24 hours of treatment, 66% of participants demonstrated a clinically significant improvement that was maintained through one month for 56% of all patients.
Go on …
Patients' vision improved, on average, from being unable to view an eye chart (referred to as “count fingers”) to 20/100; further, 44% of patients treated with the IA-tPA improved to 20/40 or better.
Expert input?
Gareth Lema, MD, PhD, the study’s leader author as well as vice chair of Quality, Safey, and Experience at NYEE, noted the protocol’s potential for not just saving eye stroke patients’ vision, but also, “the potential to use remote consultation for time-sensitive ophthalmic emergencies,” he stated.
Conclusions.
The study authors concluded a successful implementation of the remote consult protocol via a point-of-care automated OCT. This novel paradigm demonstrates the potential utility of remote consult services for the diagnosis of time-sensitive ophthalmic emergencies,” they stated.
Lastly … what’s next for this protocol?
The researchers plan on expanding OCT camera availability within the Mount Sinai Health System emergency rooms to improve the eye stroke outcomes, with an intent to reach the greater medical community and general public.
Their goal: