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Severe retinopathy of prematurity: longitudinal observation of disease and screening implications
1Faculty of Medicine, University of Calgary, Calgary, Alberta, Canada. anna.ells@calgaryhealthregion.ca
Insights
Canadian retinopathy of prematurity (ROP) screening guidelines effectively identified high-risk infants. The study refined ROP screening recommendations for premature infants based on gestational age and postmenstrual age.
Area of Science:
- Ophthalmology
- Neonatology
- Public Health
Background:
- Retinopathy of prematurity (ROP) is a significant cause of visual impairment in premature infants.
- Effective screening protocols are crucial for early detection and treatment of severe ROP.
Purpose of the Study:
- To evaluate the efficacy of Canadian ROP screening guidelines in high-risk premature infants.
- To provide evidence-based recommendations for optimizing ROP screening protocols.
Main Methods:
- A retrospective longitudinal cohort study analyzed data from 969 premature infants screened between 1991 and 2000.
- Data on ROP screening examinations, gestational age, birth weight, and treatment were collected and analyzed.
Main Results:
- The incidence of severe ROP requiring treatment was 48.3 per 1000 eligible infants.
- Infants treated had a mean gestational age of 25.5 weeks and birth weight of 750 g.
- Key ROP stages were identified at specific chronological and postmenstrual ages, guiding treatment timelines.
Conclusions:
- Recommended screening for infants ≤28 weeks gestational age (GA) at 31 weeks postmenstrual age (PMA) or 4 weeks chronological age (CA).
- Infants 28-30 weeks GA should have a single examination at ~37 weeks PMA.
- Close monitoring (1-2 weeks) for active ROP and weekly for stage 3 is advised.
Purpose:
To test the effectiveness of our Canadian retinopathy of prematurity (ROP) screening guidelines as applied to high-risk premature infants.
Study Design:
Retrospective longitudinal cohort study.
Subjects:
A total of 969 infants were examined longitudinally between 1991 and 2000 and 46 of these infants screened were treated for severe ROP.
Methods:
Data from weekly ROP screening examination results were collected from a geographical area and analysed.
Results:
The average incidence of severe ROP requiring treatment in the population of premature infants eligible for screening was 48.3 per 1000. In all, 46 infants were treated in this cohort. The mean gestational age (GA) was 25.5 weeks of age and the mean birth weight was 750 g. The mean chronological age (CA) and postmenstrual age (PMA) at the time of first screening was 36 days and 30.7 weeks, respectively. The first identification of any ROP in this group was at a mean CA 60 days and PMA of 34.1 weeks. The mean CA and PMA of the first observation of stage 3 were 74 days and 36.3 weeks. The mean CA and PMA at the time of treatment were 86 days and 37.7 week.
Conclusions:
Our observations and analysis indicate the following ROP screening recommendations: infants of 28 weeks of GA or less, infants with a GA between 28 weeks and 30 weeks should have a single 'spot examination' at approximately 37 weeks of PMA (or prior to discharge from hospital) to include possible outliers; infants born with a birth weight of 1250 g or less; initial screening examination should be at 31 weeks of PMA or 4 weeks of CA, whichever is later; in the presence of any active ROP, the infant should be followed every 1-2 weeks; and stage 3 should be followed at least every 7 days.
