J Korean Ophthalmol Soc.  2022 Jan;63(1):44-50. 10.3341/jkos.2022.63.1.44.

Effect of Mask Mandates on the Intraocular Pressure Measured via Goldmann Applanation Tonometry

• Choi WS
• Lee CH
• Lee CE
• Seo S
• Lee KW

• KMID: 2524937
• DOI: http://doi.org/10.3341/jkos.2022.63.1.44

Abstract

Purpose
The corona virus disease-19 (COVID-19) pandemic has resulted in mandatory masking of patients and physicians during outpatient visits. This study evaluated the changes in intraocular pressure (IOP) according to mask use.
Methods
This prospective study enrolled 30 healthy volunteers (60 eyes). IOP was measured via Goldmann applanation tonometry (GAT) for the subjects wearing one of four commonly used masks: dental, bi-folding Korean Filter (KF)94, tri-folding KF94, and dust masks. Subjects with IOP measurement errors of more than 5 mmHg were rechecked with another GAT type.
Results
The mean IOP measured via GAT before mask wearing was 13.7 ± 1.7 mmHg. It was 13.5 ± 2.1, 14.0 ± 2.3, 14.3 ± 2.5, and 13.8 ± 1.6 mmHg with the dental, bi-folding KF94, tri-folding KF94, and dust masks, respectively. There were no significant differences in IOP according to mask type (p = 0.635). IOP errors above 5 mmHg were detected in three subjects who had contact between the GAT feeler arm and tri-folding KF94 mask during IOP measurement.
Conclusions
The IOP as measured via GAT is artificially elevated by mechanical interference from the tri-fold KF94 mask. To minimize such mask-induced artifacts in GAT measurements, compress the patient’s mask or change the mask type to prevent any contact during measurement.

Keyword

Goldmann applanation tonometry; Mask mandates; Measurement error