Pupillary dilatation with single eyedrop mydriatic combinations

Area of Science:

• Ophthalmology
• Pharmacology

Background:

• Pupillary dilation is essential for indirect ophthalmoscopy.
• Current methods may require multiple drug instillations, increasing time and toxicity risks.

Purpose of the Study:

• To evaluate the mydriatic effect of three combination eyedrop solutions.
• To assess the impact of pre-instilled proparacaine on mydriasis.
• To determine the efficacy of a single-instillation mydriatic regimen.

Main Methods:

• Studied 80 adult patients using three mydriatic combinations: cyclopentolate HCl 0.5%/phenylephrine 2.5%, tropicamide 0.5%/phenylephrine 2.5%, and tropicamide 1.0%/phenylephrine 2.5%.
• Evaluated the effect of prior proparacaine 0.5% eyedrop instillation.
• Measured pupillary dilatation and its resistance to light.

Main Results:

• All three combination solutions achieved ~7 mm pupillary dilatation within 60 minutes.
• Proparacaine pre-instillation added ~1 mm of further dilatation.
• Mydriasis was sustained and resistant to bright light.
• Younger patients, sex, and iris color influenced dilatation extent.

Conclusions:

• A single drop of proparacaine followed by one drop of the tested mydriatic combinations provides adequate and sustained pupillary dilatation for indirect ophthalmoscopy.
• This regimen is convenient, saves time, and minimizes the risk of systemic drug toxicity compared to multiple instillations.