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Intermediate impacts of COVID-19 lockdowns on surgical glaucoma cases in Quebec, Canada: insights from a tertiary eye
Huixin Anna Zhang1, Sarah McIntyre1, Yosra Er-Reguyeg1
1Faculty of Medicine, Laval University, Quebec, G1V 5C3, Canada.
Aim:
To assess the effect of the coronavirus disease 2019 (COVID-19) pandemic on the wait times and severity of surgical glaucoma cases in a single tertiary referral center in Quebec, Canada.
Methods:
Preoperative severity data included mean visual field (VF) deficit, intraocular pressure (IOP), the number of topical glaucoma medication classes, and preoperative best corrected visual acuity (BCVA). The times from referral to procedure (referral time) and from listing date to procedure (waitlisting time) were calculated.
Results:
This retrospective cohort study involved 181 eyes of patients undergoing glaucoma surgery from March 1 to June 30, 2019 (pre-pandemic period), and 201 eyes in the same timeframe in 2021 (pandemic period) at Saint-Sacrement Hospital in Quebec City. There was no significant difference in the severity data of surgical glaucoma across both periods (VF deficit: P=0.48; IOP: P=0.14; BCVA: P=0.24; topical medication classes: P=0.27). The number of patients referred with oral glaucoma medication increased slightly from 45 to 70 in 2019 and 2021 respectively (P=0.08). Delay data were also comparable. Mean referral time was 122±120d in 2019 versus 144±136d in 2021 (P=0.09), whereas waitlisting time before the pandemic was 43±44.5 versus 39±41.8d in 2021 (P=0.13).
Conclusion:
Despite North America's strictest pandemic restrictions, limited negative impact is observed on waitlisting delays and the severity of glaucoma cases presenting at our center. A larger subset of patients is treated with oral medications indicating a possible increase in advanced glaucoma.
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