Very premature babies are at high-risk for many health issues including permanent blindness associated with retinopathy of prematurity (ROP). Because of the risk of blindness, routine eye tests are performed to determine the presence and severity of ROP. Screening for the condition requires the use of pupil dilating medications which are associated with a host of side-effects including increased blood pressure, apnoea and necrotising enterocolitis. Inconsistencies in best-practice for pupil-dilation dosage have been found, with some hospitals using higher doses than what is used in adults. This study could answer important questions as to the effectiveness and safety of low dose and very low dose microdrop regimens when screening premature babies for ROP. This research has the potential to inform guidelines both here and internationally, which would represent a significant impact on health outcomes for vulnerable babies.