Purchase this article with an account.
Michael Bannon, Jaana Ashtiana-Zarandi, Alexandra Beachnau, Pranaya Bista, Russell Lake, Pedram Pourhosseini, Maria-Alessandra Roa, Nazli Sammak, George McArdle, Rebecca K Zoltoski; Combining dilating drops in different solutions can provide a larger dilation. Invest. Ophthalmol. Vis. Sci. 2019;60(9):3361.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
Mydriasis is an important tool used in ophthalmological and optometric clinical practice since a large or very large pupil size and stable dilation is necessary for a complete fundus exam or any procedure that needs to visualize as much of the lens as possible. The most commonly used drugs to obtain a large dilation that occurs quickly but last a long time are 2.5 % phenylephrine (P) and 0.5% tropicamide (T) as separate drops administered 5 – 15 seconds apart. Methods to make these tools quicker and more long-lasting, but still safe are being assessed to reduce the clinical costs of repeated administration of these drops. The addition of topical nonsteroidal anti-inflammatory drops, as a new therapy method, such as 0.5% ketorolac (K) have been shown to be effective in controlling post-operative pain, inflammation and maintenance of mydriasis during cataract surgery. We conducted a quantitative study to assess if using the drugs together in one thicker solution and adding K would cause increase size or duration of dilation.
After verifying eligibility, we measured pupil size using a Neuroptics pupillometer prior to and every 30 minutes for two hours following dilation of one eye using one drop of each solution. The 3 groups we used were 2.5% P and 0.5% T, one drop of each separated by 15 secs (P&TD, n=55), 2.5 % P, 0.5% T, and 0.5% K in an artificial tear solution (PTKD, n=24) or 2.5 % P, 0.5% T, and 0.5% K in a thicker artificial tear solution (PTKG, n=26).
Following one drop application an increase in pupil size was seen starting at the 30 min measurement and latest the entire two hours in all groups. The time to maximal dilation was about an hour and 15 mins in all groups. The average maximal dilation was 1.9 ± 0.1 mm, 3.5 ± 0.2 mm, and 4.0 ± 0.2 mm in P&TD, PTKD, and PTKG, respectively. However, the largest pupil size was similar across all 3 groups, 8.2 ± 0.1 mm, 7.7 ± 0.2 mm, and 8.1 ± 0.2 mm in P&TD, PTKD, and PTKG, respectively.
The addition of K to the drug grouping as well as combining the drops appears to have increased the maximal dilation obtained. Making the dilating solution thicker did not cause any increased benefit. Time in pre-operative care might be reduced by using a solution containing all 3 drugs. Analysis of the data across age, race, and iris color might provide further information on the usefulness of these solutions.
This abstract was presented at the 2019 ARVO Annual Meeting, held in Vancouver, Canada, April 28 - May 2, 2019.
This PDF is available to Subscribers Only