Optimizing visible retinal area in pediatric ultra-widefield fundus imaging: The effectiveness of mydriasis and eyelid lifting

• Combining mydriasis with manual eyelid lifting significantly enhances the VRA in ultra-widefield fundus imaging. • Eyelid lifting eliminated the significance of VRA differences between dilated and undilated conditions, suggesting that children need to lift their eyelids as much as possible to expose the VRA when taking ultra-widefield fundus images. • UCVA,SER and AL correlate with VRA in children on ultra-widefield fundus imaging. The increase in visible retinal area (VRA) enhances the detection of peripheral retinal pathologies. This study aims to maximize the VRA in children using ultra-widefield (UWF) fundus imaging. This cross-sectional, observational study included 53 children (106 eyes) who underwent examination in the Ophthalmology Department of Zhoupu Hospital from February to October 2023. Fundus images were captured using the ultra-widefield Optos imaging system (Daytona P200T). Parameters such as uncorrected visual acuity (UCVA), Spherical equivalent refraction (SER), axial length (AL), non-contact tonometry (NCT), and pupil diameters (both undilated and dilated) were measured. A custom image segmentation tool based on deep learning technology was used to quantify the VRA. The eyes were categorized into four groups: undilated without eyelid lifting, undilated with eyelid lifting, dilated without eyelid lifting, and dilated with eyelid lifting. Significant differences in VRA between the four groups (χ² = 79.686, P < 0.001). Mydriasis increased VRA by 8.4 % ( P = 0.001), eyelid lifting increased VRA by 18.1 % ( P < 0.001), and combining both increased VRA by 20 % ( P < 0.001). UCVA was negatively correlated with VRA in the undilated condition without eyelid lifting ( r = -0.237, P = 0.014), SER was negatively correlated with VRA and AL was positively correlated with VRA under dilation without eyelid lifting ( r = -0.310, P = 0.001; r = 0.264, P = 0.006). Combining mydriasis with manual eyelid lifting significantly enhances the VRA in UWF fundus imaging, effectively mitigating the effects of artifacts caused by eyelashes and eyelids. This technique improves the detection rate of peripheral retinal pathologies.