Validation of a device for assessing the severity of Meibomian gland dysfunction

This study aimed to validate the efficacy of a handheld force-measuring device in quantifying the severity of obstructive Meibomian gland dysfunction. Utilizing a force-sensitive resistor (FSR 400 series, Interlink Electronics, CA, USA), the device's precision and accuracy were assessed. Masses were incrementally placed on the FSR, and the resulting data were recorded with an ATmega328P and ATMega 16U2 processor microcontroller (Arduino, Italy). A 3D-printed device weighing 18.3g applied the masses in a logarithmic sequence, mirroring the forces from a gentle blink (1.25 g/square mm) to a painfully high pressure of 1005.3 g (80 g/square mm). For each mass, the FSR recorded 60 readings over 3 seconds (at intervals of 50 milliseconds), which were then averaged. Three trials per mass ensured reliability, with a randomized sequence and interspersed 20-minute breaks to emulate clinical conditions. The decision tree model yielded a mean square error (MSE) of 65.08 and an R-squared score of 0.999, indicating high accuracy. Polynomial regression analysis, used to check for overfitting, revealed a degree-3 model with an MSE of 2133.39 and an R-squared of 0.98. Predicted values within a 95% confidence interval are detailed in Table 1. Bland-Altman analysis confirmed the agreement limits (28.44 to 48.11) for the lower mass experiment, with data evenly spread and no proportional bias detected. The FSR demonstrated high accuracy and consistent performance, with suitably narrow limits of agreement. The device effectively measures the force applied to the eyelid for Meibomian gland expression, providing an objective metric for the degree of obstruction. This abstract was presented at the 2024 ARVO Annual Meeting, held in Seattle, WA, May 5-9, 2024. Predicted values (95% confidence interval)