[Investigation of Successful Eyedrop Instillation Rates and Analysis of Drop Positions Using High-speed Digital Video...

Area of Science:

• Ophthalmology
• Biomedical Engineering
• Patient Adherence Studies

Background:

• Eyedrop adherence studies often assume successful instillation.
• The optimal distance between the eyedropper and the cornea is not well-defined, with a common estimate of 2.54 cm (1 inch).
• Understanding accurate eyedrop instillation techniques is crucial for effective ocular treatment.

Purpose of the Study:

• To investigate the success rates of eyedrop instillation in a volunteer cohort.
• To determine the relationship between the distance from the dropper tip to the cornea and successful eyedrop delivery.
• To assess current eyedrop instillation practices and identify areas for improvement.

Main Methods:

• High-speed digital video recording was used to analyze eyedrop instillation in 100 volunteers.
• Successful instillation was defined as accurate delivery of one drop on the first attempt.
• Distances were measured from paused video frames using a digital ruler.

Main Results:

• The overall success rate for first-time eyedrop instillation was 70.1%.
• The average distance between the dropper tip and cornea was 2.62±1.75 cm (median 2.20 cm).
• Success rates varied with distance: 77% at 1.6±0.88 cm versus 54.9% at 4.8±1.25 cm.

Conclusions:

• The generally recommended eyedrop instillation distance is often followed, but not always optimal.
• A shorter distance (around 1.6 cm) between the dropper tip and cornea significantly improves successful eyedrop instillation rates.
• Patient education on proper eyedrop technique is essential, as 40% of volunteers received no prior instructions.