Timing of Retinopathy of Prematurity Diagnosis and Treatment in Micro-Premature and Nano-Premature Infants during Inpatient Screening.

Objective: We aimed to determine the timing of retinopathy of prematurity (ROP) diagnosis and treatment in a cohort of infants meeting criteria for micro- and/or nano-prematurity with the goal of informing screening protocols in this high-risk group.

Design: Retrospective consecutive study.

Participants: We included all screened infants who met the criteria for micro-prematurity (24-26 weeks gestational age [GA] and/or birth weight [BW] 600-799 grams) or nano-prematurity (<24 weeks GA and/or BW <600 grams).

Methods: Data collected from 2013 to 2023 included GA at birth, BW, postmenstrual age (PMA) at ROP diagnosis, PMA at type 1 ROP diagnosis, and number of inpatient examinations.

Main outcome measures: Rates of ROP and treatment-warranted ROP, timing to first ROP diagnosis and treatment-warranted ROP, and the number of examinations.

Results: 3239 infants were screened during this time period for ROP, and 650 infants met inclusion criteria. The median GA at birth and BW were 25.3 weeks and 682.5 g, respectively. Four hundred fifty-six infants (70.2%) were micro-premature and 194 (29.8%) were nano-premature. Retinopathy of prematurity was detected in 524 patients (80.6%). The median PMA at first ROP diagnosis was 33.7 weeks. The median interval from birth to first ROP diagnosis was 8.4 weeks. The median examination number at first ROP diagnosis was the second examination. The median number of inpatient examinations was 9. Of ROP patients, 180 (34.4%) had ROP diagnosis at their first examination. A total of 126 (19.4% of all infants and 24.0% of those with ROP) infants met type 1 treatment criteria. The median PMA at type 1 ROP diagnosis was 37 weeks. The median interval from birth to type 1 ROP was 12 weeks. The median examination number at type 1 diagnosis was the fifth examination.

Conclusions: In this modern cohort of high-risk extremely premature infants, 9 patients (1.4%) were diagnosed with type 1 ROP on the first or second inpatient exams. These infants had generally good outcomes after treatment, with only 2 eyes of 1 patient progressing to stage 4 disease. Our findings support maintaining current screening guidelines for high-risk extremely premature infants, while suggesting opportunities for optimizing screening approaches through risk stratification.

Financial disclosure(s): Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.