A comparison of cardiorespiratory responses during ROP screening using ultra-widefield scanning laser ophthalmoscopy (UWF-SLO) versus binocular indirect ophthalmoscopy (BIO)

Abstract

Purpose : Imaging-based retinopathy of prematurity (ROP) screening using UWF-SLO provides a potential alternative to traditional indented BIO examination, and may be better tolerated by infants. We aim to assess the safety of UWF-SLO based ROP screening by comparing physiological responses of infants examined using both methods.

Methods : Pooled data from three prospective cohorts totaling 86 infants (46 males and 40 females) undergoing ROP screening were included in the study. 44 infants were examined by optomap imaging (California rg, Optos plc, Dunfermline, UK) with ‘flying baby’ technique and 42 by BIO with scleral indentation. The same neonatal wire speculum was used for both groups. Infants were aged between 30+3 and 44+3 weeks postmenstrual age. Vital signs were continuously recorded via a laptop connected to hospital monitors. Heart rate (HR) and oxygen saturation (SpO₂) were examined for 10 min before and after the start of ROP screening. Increase in HR and decrease in SpO₂ were calculated above or below the infant’s baseline range (mean ± two standard deviations). The maximum change in HR and minimum change in SpO₂ were calculated from the infant’s baseline mean. Bradycardia, tachycardia and oxygen desaturation were identified using standard clinical definitions. Data was analysed using linear regression, correcting for birthweight, gestational age at birth/examination, and baseline HR and SpO₂ for their respective parameters.

Results : Figure 1 shows the average change in HR and SpO₂ in the two groups. No significant difference in terms of increase in HR (p=0.18) or decrease in SpO₂ (p=0.88) was detected between the two screening methods. The maximum change from baseline in HR was lower in the UWF-SLO group by a mean of 9.1 beat/min (p=0.024). There was no statistical difference in the occurrence of bradycardia (p=0.73), tachycardia (p=0.32) or oxygen desaturation (p=0.93).

Conclusions : Our results indicate that ROP screening using UWF-SLO is safe when evaluated using cardiorespiratory markers. Less fluctuation (changes from baseline) in HR was seen in the UWF-SLO group, indicative of good tolerability. Although there was no statistically significance difference in the rate of tachycardia between the two groups, the mean HR trended lower during ROP examination with UWF-SLO.

This abstract was presented at the 2023 ARVO Annual Meeting, held in New Orleans, LA, April 23-27, 2023.