Development and Assessment of an Inexpensive Smartphone-Based Respiratory Droplet Simulation Model

Abstract

Background. Droplet simulation often requires expensive and inaccessible equipment. Herein, we develop and assess a low-cost droplet simulation model using easily accessible materials, open-source software, and a smartphone-based cobalt blue light. Methods. The simulation model was developed using commercial-grade materials and fluorescein dye. A clear face shield was assessed ten times following a simulated cough using fluorescein dye. A conventional ultraviolet Woods lamp was compared to a smartphone-based cobalt blue light to detect fluorescein illumination. Results. The simulation platform and smartphone-based cobalt blue light cost $20.18. A Wilcoxon signed rank test revealed that the median droplet area of fluorescence under the UV Wood’s lamp was not significantly different than that of the smartphone-based cobalt blue light (2.89 vs 2.94, P = .386). Conclusions. This simulation model is inexpensive and easily reproducible. The smartphone application may be a convenient alternative to standard ultraviolet lights. This model has great potential for use in financially restricted academic centers during the COVID-19 pandemic and beyond.

Detecting corneal injury with a selfie

“…Our group has previously demonstrated the fluorescein‐illuminating capabilities of a cobalt blue smartphone LCD screen 6,8,9 . However, its use was previously limited by the need for two smartphones: one presenting the cobalt blue screen to the patient's affected eye and a second to capture a photograph.…”

“…7 Our group has previously demonstrated the fluoresceinilluminating capabilities of a cobalt blue smartphone LCD screen. 6,8,9 However, its use was previously limited by the need for two smartphones: one presenting the cobalt blue screen to the patient's affected eye and a second to capture a photograph. The new "Cobalt Blue Selfie" mode obviates the need for a second smartphone, allowing providers and patients to capture fluorescein-illuminated photographs much like they would obtain a selfie.…”