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  • Nanodropper Versus Standard Eyedropper for Pupillary Dilation

    By Lynda Seminara
    Selected by Russell N. Van Gelder, MD, PhD
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    Journal Highlights

    Ophthalmology, March 2023

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    Concerns about standard eyedroppers include product waste, potential over­medication, and patient discomfort. For instance, evidence suggests that for every drop instilled successfully, seven drops are wasted. In a random­ized noninferiority study in children, Hoppe et al. compared efficacy for a standard-of-care (SOC) eyedropper (50-μL dispersion) and smaller-volume administration (10.4-μL dispersion) via the Nanodropper adapter. For pupillary dilation, they found that the Nano­dropper was not inferior to SOC.

    Participants of the study were chil­dren (mean age, 9 years) scheduled for routine pupillary dilation at a pediatric ophthalmology clinic in San Francisco. Each received SOC in one eye and Nanodropper delivery in the other eye. SOC eyes served as the controls. The eye selected for each treatment was determined randomly for each patient. Pupillary dilation was performed with one drop of 1% cyclopentolate, fol­lowed by one drop of 1% tropicamide, then one drop of 2.5% phenylephrine. The right eye of each patient was the first to receive drops, regardless of its treatment assignment. Refraction and pupillometry were conducted before instillation of the drops and 30 minutes afterward. The main outcomes were changes from baseline (before drop in­stillation) in spherical equivalent, pupil constriction percentage, and maximum pupil diameter.

    Fifty patients (100 eyes) were in­cluded. After controlling for baseline variables, the spherical equivalent 30 minutes after drop instillation was .05 D greater in the Nanodropper group, which did not meet criteria for nonin­feriority.

    The maximum pupil diameter achieved from dilation was lower in the Nanodropper group, but the difference was small enough to denote noninfe­riority. The constriction percentage achieved from dilation was .57 percent­age points higher in the Nanodropper group, which did not represent nonin­feriority. When accounting for multi­plicity, statistical significance was not achieved for any outcome measure.

    Although strict noninferiority was achieved for pupillary dilation but not for cycloplegia or constriction per­centage, the between-group difference in any outcome was not clinically significant, said the authors. Even so, they concluded, replacing SOC with small-volume eyedroppers should decrease medical waste and reduce the risk of local and systemic toxicity.

    The original article can be found here.