Future Research Perspective on the Interfacial Physics of Non-Invasive Glaucoma Testing in Pathogen Transmission from the Eyes

TL;DR

This paper reviews the physics of non-contact tonometry (NCT) in glaucoma testing, emphasizing the need for interdisciplinary research on fluid dynamics and pathogen transmission to improve safety and understanding.

Contribution

It highlights unexplored interfacial physics and pathogen transmission routes in NCT, proposing future research directions for safer and more effective glaucoma testing.

Findings

Identification of complex fluid-solid interactions during NCT

Potential pathogen transmission via tear film droplets

Need for interdisciplinary research on ocular biointerface

Abstract

Non-contact Tonometry (NCT) is a non-invasive ophthalmologic technique to measure intraocular pressure (IOP) using an air puff for routine glaucoma testing. Although IOP measurement using NCT has been perfected over many years, various phenomenological aspects of interfacial physics, fluid structure interaction, waves on corneal surface, and pathogen transmission routes to name a few are inherently unexplored. Research investigating the interdisciplinary physics of the ocular biointerface and of the NCT procedure is sparse and hence remains to be explored in sufficient depth. In this perspective piece, we introduce NCT and propose future research prospects that can be undertaken for a better understanding of the various hydrodynamic processes that occur during NCT from a pathogen transmission viewpoint. In particular, the research directions include the characterization and measurement of the incoming air puff, understanding the complex fluid-solid interactions occurring between the air puff and the human eye for measuring IOP, investigating the various waves that form and travel; tear film breakup and subsequent droplet formation mechanisms at various spatiotemporal length scales. Further, from ocular disease transmission perspective, the disintegration of the tear film into droplets and aerosols poses a potential pathogen transmission route during NCT for pathogens residing in nasolacrimal and nasopharynx pathways. Adequate precautions by opthalmologist and medical practioners are therefore necessary to conduct the IOP measurements in a clinically safer way to prevent the risk associated with pathogen transmission from ocular diseases like conjunctivitis, keratitis and COVID-19 during the NCT procedure.