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Randomized Controlled Trial Comparing the Efficacy of Mydrin-P Microdrops Over Standard Dose Mydrin-P for Pupil
Evelyn Lu1,2, Ka Yin Leung3, Wilfred Hing Sang Wong1
1The Department of Paediatrics and Adolescent Medicine, School of Clinical Medicine, The University of Hong Kong, Hong Kong, China.
Purpose:
To compare the efficacy of a reduced dose of Mydrin-P (0.5% tropicamide and 0.5% phenylephrine hydrochloride) (Santen Pharmaceutical) using micro-drops with standard Mydrin-P eye drops for retinopathy of prematurity (ROP) examinations.
Methods:
A prospective, randomized controlled, non-inferiority study was conducted in a single neonatal intensive care unit in Hong Kong. Eighteen infants with an estimated gestational age at birth of 32 weeks or less and/or birth weight of 1,500 g or less were recruited and randomized to receive either standard Mydrin-P eye drops or Mydrin-P microdrops (one-third of the standard dose). All patients were subsequently examined by an ophthalmologist for the presence of ROP. Serial pupil diameters and other clinical parameters were also measured after mydriatics were applied.
Results:
Eighteen infants with 46 eye examinations for ROP were included. All fundus examinations with microdrop instillation led to successful ROP assessments with no statistically significant difference compared to standard eye drops (P = .233). Mean pupil diameter did not differ between the microdrop (5.73 mm) and standard eye drop (5.47 mm) groups at the time of examination. No statistically significant difference in systemic side effects was observed between the two groups.
Conclusions:
Mydriatic Mydrin-P microdrops demonstrated similar efficacy compared to standard Mydrin-P eye drops and should replace standard Mydrin-P for ROP screening in preterm infants with potentially fewer side effects.
Insights
Reduced-dose Mydrin-P micro-drops are as effective as standard Mydrin-P eye drops for retinopathy of prematurity (ROP) screening in preterm infants. This micro-drop approach may offer fewer side effects.
Area of Science:
- Ophthalmology
- Neonatology
- Pharmacology
Background:
- Retinopathy of prematurity (ROP) requires timely screening in preterm infants.
- Standard mydriatic eye drops are used for ROP examinations.
- Optimizing drug delivery and minimizing side effects are crucial in neonatal care.
Purpose of the Study:
- To compare the efficacy of reduced-dose Mydrin-P micro-drops versus standard Mydrin-P eye drops for ROP examinations.
- To assess pupil dilation and potential systemic side effects of both formulations.
Main Methods:
- A prospective, randomized controlled, non-inferiority study.
- 18 infants (gestational age ≤32 weeks or birth weight ≤1,500 g) received either standard or micro-dose Mydrin-P.
- Ophthalmological examination for ROP and measurement of pupil diameter and clinical parameters.
Main Results:
- Successful ROP assessments were achieved in all fundus examinations using microdrops, with no significant difference compared to standard drops (P = .233).
- Mean pupil diameters were similar between the microdrop (5.73 mm) and standard (5.47 mm) groups.
- No statistically significant differences in systemic side effects were observed between the groups.
Conclusions:
- Mydrin-P micro-drops demonstrate comparable efficacy to standard Mydrin-P eye drops for ROP screening.
- Reduced-dose Mydrin-P micro-drops are a viable alternative for ROP screening in preterm infants.
- This approach may lead to a reduction in potential side effects.
