Face Masks may cause Visual Symptoms and Artifacts in Ophthalmic Patients

28 Purpose: To investigate the characteristics of mask wearing and the effect of masks on visual 29 symptoms and clinical measurements in a sample of ophthalmic patients in Ghana. 30 Methods: A clinic-based cross-sectional descriptive study was conducted among ophthalmic 31 patients who visited two primary care eye clinics in the Central Region of Ghana. Participants 32 included 71 randomly sampled patients aged 18 years and above and consented to take part in the 33 study. Their mean ages (SD) was 36.94±17.46 and they were made up of 27(38%) males and 34 44(62%) females. The patients responded to symptoms assessment questionnaire before their 35 visual acuity (VA) for distance and near and IOPs with and without their face masks were 36 measured. 37 Results: The majority 45(63.4%) of the patients’ used fabric masks and 25(35.2%) reported 38 ocular problems with the use of the masks. Of those who observed ocular problems, 8(32%) 39 observed problems with the use of spectacles, and 5(20%) also observed problems with their 40 vision. The mean difference in distance VA with and without face mask for the right eye was 41 0.08(0.36) and left eye was 0.05(0.25) MAR, indicating slight aberrations in vision. Mean 42 differences in measurements with and without face masks were not statistically significantly 43 different ( P < 0.05). A higher proportion of persons wearing KN95 experience nausea or 44 headaches ( ꭓ =18.610, p<0.001) and discomfort of wearing of nose mask ( ꭓ =7.803, p=0.020). 45 None of those wearing a fabric face mask reported of difficulty in accurately reaching for objects 46 with the nose mask on. ( ꭓ = 8.664, p=0.13). Face may oculo-visual in ophthalmic patients, which practitioners must


Introduction
Ghana, have enacted legislation making it compulsory for individuals to wear face masks at 77 every social gathering including hospitals and clinics 14,15 . Recent survey conduct in Ghana 78 revealed that 82% of persons surveyed were using face masks. The same survey however found 79 that only 44.3% of those who have mask use them correctly. The incorrect use of a face masks

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Material and methods

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The study employed a clinic-based cross-sectional study design by recruiting regular ophthalmic 93 patients who reported to the Eye Clinics of two hospital facilities in the Central Region of 94 Ghana, that is, the University of Cape Coast Hospital and Our Lady of Grace Hospital, Breman

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Esikuma during the period 20 th July to 3 rd August 2020, and following the lifting of lockdown 96 rules.
Data were collected in two parts. First, questionnaires were interviewer-administered by questionnaire contained questions on patients' demographics, type of face mask worn, and ocular 102 symptoms experienced when wearing their face masks.

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The second part involved optometrists measuring the patients' visual acuities for both distance 104 and near visions, with and without their face masks on. Also, their intraocular pressures were 105 measured during the slit-lamp examination of patients with and without their face masks on for 106 each eye. All measurements were repeated twice and an average used. For visual measurements taken without face masks, patients were instructed to take their masks off briefly, 30 minutes after the initial measurement while the examiner wore their facemask and goggles under a 109 transparent shield at all times. Examiners crosschecked to make sure that their face masks were 110 at all times properly fitted and did not interfere with measurements taken. The examination room 111 was frequently sanitized and ophthalmic equipment sterilized after each patient's examination.

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Visual acuity measurements were recorded in LogMAR acuity and the intraocular pressure were 113 recorded in millimeters of mercury (mmHg). LogMAR acuity measurements have been known 114 to be more sensitive when observing interocular differences in Visual acuity compared to other 115 visual acuity measures especially snellen 19 .
Data was recorded in Microsoft Excel spreadsheets (Microsoft Corporation, Redmond, WA, distributions. A two-tailed t-test was used to determine mean differences (MD) in visual acuity 121 and intraocular pressure measures at a confidence interval of 95%. LogMAR values were 122 linearised by converting them MAR to calculate the mean deviation from the "unlogged" 123 values. P-values < 0.05 were considered to be statistically significant. 152 (ꭓ= 8.664, p=0.13). The association between symptoms reported and types of face mask worn 153 are shown in Table 2.

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Though the data from this study did not support the hypothesis that face marks may bias or skew 210 clinical measurements, as seen from the lack of meaningful differences in Table 2

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This study revealed that the most common face mask used by the patients was the fabric masks

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To the best of our knowledge, no study has been clinically reported on the introduction of ocular presence of a pre-shaped rigid nose area that may have pressed against the Goldmann tonometer.

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The lack of information may be attributed to the changing dynamics of the coronavirus disease, Whiles this study is relevant for clinical practice and patient education, the application of the results is limited by the small number of patients sampled, and the possible errors introduced by 268 examiners wearing face masks whiles taking the measurements despite the precautions taken.

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We recommend further large-scale studies that involve a large number of subjects and designs 270 that will possibly expunge errors introduced by examiners face masks.

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The authors did not receive support from any organization for the submitted work.

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Data used for this study is contained in the manuscript and available from the authors upon