Association Between Screen Time and Tear Film Stability

Tear �lm is a layer that nourishes, lubricates and protects the anterior surface of eye. The usage of electronic gadgets can affect the tear �lm stability causing ocular dryness. Recently, due to the increased frequency of online educational and leisure activities, there has been reported increase in the prevalence of dry eye among users of electronic gadgets. Objective: To evaluate association between screen time and stability of tear �lm. Methods: A descriptive cross-sectional study was conducted from January to august 2021 at The University of Lahore. 120 participants aged above 18 years were recruited using nonprobability sampling technique. After taking consent from the participant's questionnaire was completed, followed by slit lamp examination for evaluation tear �lm breakup time (TBUT). Results: 120 healthy people of either gender who were at least 18 years old participated in this study, selected through random sampling, informed consent was acquired from all participants. The TBUT test was performed on all subjects, 74 had severe dry eyes, 21 had moderate dry eyes, and just 24 had normal eyes. Each subject's screen time was tracked after the subjects were divided into four groups. The Chi square was used to assess the relationship between screen time and tear �lm break up time. Results had a p value less than 0.01 and were statistically signi�cant. Conclusions: This study concluded that as the screen time increases it effects the stability of tear �lm.


Association Between Screen Time and Tear Film Stability
provide a smooth surface and retard the rate of tear evaporation from the cornea [5]. The aqueous layer, which is made of water and helps the tear lm spread, gives the cornea oxygen and nutrients [6]. The accessory lacrimal glands, such as the wolfring and Krause glands, are responsible for the basal secretion of the second layer of tear lm [7] whereas the primary lacrimal gland is responsible for re ex tear lm secretion. This layer is mildly alkaline and has an osmolarity of 300 mOsm/l [8]. The tear lm's innermost layer acts as an anchor and promotes tear lm adhesion to the eye [9]. It is important for protection of anterior corneal surface, act as a polish for cornea. One of the most signi cant characteristics of tear lm is its stability, which is required for ocular surface protection. All Screen Time and Tear Film Stability

I N T R O D U C T I O N
Tear lm is a layer that nourishes, lubricates and protects the anterior surface of eye. The usage of electronic gadgets can affect the tear lm stability causing ocular dryness. Recently, due to the increased frequency of online educational and leisure activities, there has been reported increase in the prevalence of dry eye among users of electronic gadgets. Objective: To evaluate association between screen time and stability of tear lm. Methods: A descriptive crosssectional study was conducted from January to august 2021 at The University of Lahore. 120 participants aged above 18 years were recruited using nonprobability sampling technique. After taking consent from the participant's questionnaire was completed, followed by slit lamp examination for evaluation tear lm breakup time (TBUT). Results: 120 healthy people of either gender who were at least 18 years old participated in this study, selected through random sampling, informed consent was acquired from all participants. The TBUT test was performed on all subjects, 74 had severe dry eyes, 21 had moderate dry eyes, and just 24 had normal eyes. Each subject's screen time was tracked after the subjects were divided into four groups. The Chi square was used to assess the relationship between screen time and tear lm break up time. Results had a p value less than 0.01 and were statistically signi cant. Conclusions: This study concluded that as the screen time increases it effects the stability of tear lm.

M E T H O D S
of the tear lm's components and layers, such as the lipid layer, aqueous layer, and mucin layer, must be present to keep the tear lm stable [10]. Tear lm not only protects from dryness, infection it also maintains the transparency of cornea and is essential for the optimal functioning of the eyes. It nourishes, lubricates and protects anterior surface of eyes. Tears are continuously absorbed and evaporated from the ocular surface [11]. When digital devices are excessively used then blink rate decreases signi cantly because of which Meibomian glands are not su ciently stimulated to release the tear lm's lipid layer [12]. The use of computers, laptops, tablets, and smartphones has steadily increased over the past few years with the passage of time and the development of technology [13]. The intermediate holding distance required by these digital devices puts pressure on the visual system, which is designed for comfortable near and distant vision [14]. The use of these electronic devices has signi cantly increased during the previous few years [15]. According to optometric association two hours of continuous screen time per day is enough for causing eye related problems like decrease blink rate and dryness [16]. Digital eye strain is a manifestation of evaporative dry eye it is increased in COVID pandemic [17] as the whole learning system has been shifted to the online classes and are using their tablets, mobiles and laptop more often for educational as well as sports/leisure time [18].
From January 2021 to August 2021, 120 (n=z2pq/e2) subjects selected through convenient sampling were included in this descriptive cross-sectional study conducted at The University of Lahore. All the subjects with age limit 18-30 were included. patients with mental retardation, systemic, congenital, or ocular disorders were excluded, as well patients who had undergone any eye surgery or who had worn contact lenses. Each subject's proper informed consent was obtained. Depending on their age, patients were placed into three groups. Group 1 includes respondents between the ages of 18 and 21; Group 2 includes subjects between the ages of 22 and 25; and Group 3 includes subjects between the ages of 26 and 30. Data were collected from the subjects with the help of selfdesigned Performa The Performa was created to gather data regarding screen time. After taking proper history, Performa was administered to evaluate subjects screen time then tear lm stability was examined by tear lm break up time in which uorescein dye was instilled in eyes then subject is instructed to not blink adjust patient on slit lamp and start examining on cobalt blue illumination The length of time between the nal blink and the appearance of the rst dry area in the tear lm is known as the tear break up time. Three categories are used to classify tear lm breakup times. Less than ve seconds are regarded as low, between ve and ten seconds as marginal, and more than ten seconds as normal. SPSS version 21.0 was used to analyze the data.

R E S U L T S
This study consisted of both eyes of 120 normal subjects of either gender aged above 18years from all subjects informed consent was obtained. The overall number of subjects in Group 1 (18 to 21 years), Group 2 (22 to 25 years), and Group 3 (26 to 30 years) was 37 (30.8%), 50 (41.7%), and 33 (27.5%), respectively. A total of 57 females and 63 guys made up the sample. Males were more common than females (52.5% vs. 47.5%), by a wide margin. TBUT test was performed on all 120 subjects out of which 79(65.8%) had severe dry eye while 26(21.7%) had moderate dry eye and only 15(12.5%) subjects were normal. Screen use of total 120 subjects were divided in to four categories, screen time was measured in 120 subjects out of which 79(63.3%) had screen time more than 8 , 24(21.7%) subjects had screen time more than 6 hours, 12 subjects had screen time of 3-5(10.0%) hours while on only 8(6.7%) subjects had screen time less than 1-2 hours. Chi square was used to assess the relationship between screen time and tear lm break up time. Chi square shows signi cant p value < 0.01 relationship between screen time and tear lm stability.it means as the screen time increases it effects the stability of tear lm. Total 120 subjects were included in this study of either gender male or female age ranging from 18 above years of age. All individuals were divided in to three age groups. Total 37 subjects were lies in 18-251years of age. 50 individuals are in group 22-25 and only 33subjects were presented with ages 26-30 year of age. As shown in table 1.  Table 2 shows chi square analysis of total 120 subjects were included on which TBUT was performed on screen users, divided into 3 categories. (74) subjects having screen time of more than 8 hours have sever tear lm instability (< 5 seconds), 21 subjects having screen time more than 6 hours have moderate tear lm instability (5-10 seconds), 24 subjects having screen time more than 6 hours are normal (> 10 seconds). Study shows signi cant results(p<0.01). In this clinical research we assessed the relationship between screen time and tear lm stability, screen time was assessed by self-designed Performa while tear lm stability was assessed by tear lm break up time. Screen time was divided into 4 categories while tear lm stability was divided into three categories. Our study shows signi cant relationship (p=<0.01). In 2021, Verma et al., did a cross-sectional study at a teaching institute to determine the prevalence of computer vision syndrome and dry eye in computer operators. One hundred participants were included in the study based on the inclusion criteria [19]. A questionnaire was created to enquire about CVS symptoms. The Ocular Surface Disease Index (OSDI), refraction, Schirmer's test 1, and tear lm break-up time (TBUT) were all carried out. The data were gathered and analyzed using SPSS software. 74% of people were found to have CVS. 39 women and 61 men made up the study's sample size. Depending on the working hours, the majority of the participants (37.84%) worked 4-8 hours every day. 37.84% of participants who worked between 4 and 8 hours did so. According to the OSDI score, 41 individuals had moderate dry eye and 23 individuals had mild dry eye. 58% of the left eye and 59% of the right eye both had dry eyes. The study's conclusion is that the prevalence of dry eye has increased as a result of the increased use of computers in daily lives. Similarly, in our study120 subjects those who were screen users, divided into 3 categories. (74) subjects having screen time of more than 8 hours have sever tear lm instability (< 5 seconds), 21 subjects having screen time more than 6 hours have moderate tear lm instability (5-10 seconds), our study co relate with results of our study that screen time has signi cant effect on tear lm stability [19]. Peak Kyung's study, which he conducted among college students to evaluate the association between addictive smart phone use, dry eye syndrome, upper extremity discomfort, and depression, produced results that were in agreement with those of our study. A self-report questionnaire was utilized to gather data from 286 college students for this study. 15.0 % of people reported having a smartphone addiction. Our study likewise came to the same conclusion that increasing screen time has a serious negative impact on eyes, inducing dryness, comparable to his study's conclusion that addicted smart phone use has large disparities in dry eye [20]. Our ndings were consistent with a study conducted by Loebis et al., on the relationship between exposure time to mobile devices and the prevalence of evaporative dry eyes as one of the symptoms of computer vision syndrome among Senior High School Students. The data show that 94 students participated in this study. There were 82 students overall who had evaporative dry eyes (87.2%). Thirteen kids (11.7%), 18 students (19.1%), and 53 students (56.4%) had dry eyes as a result of low exposure, moderate exposure, or high exposure, respectively. A chi square analysis revealed that all HEV exposures have a comparable likelihood of resulting in dry eyes in high school students (p 0.05). This study found that even minimal exposure to mobile devices may increase the risk of developing evaporative dry eyes, one of the symptoms of CVS in young persons with normal tear production [21].
C O N C L U S I O N S < 5 seconds (Low) 5-10 seconds (Marginal) >10seconds (normal) Total

TBUT
According to my study there is greatest statistical signi cance between screen time and dry eyes. Stability of tear lm greatly decrease with the increased screen time(p<0.01). Results of study concluded that screen time has signi cantly increased during COVID time which has greatly affected the stability of tear lm and daily number of students are reporting to clinical set ups with the problem of dry eye.
Yokoi N and Georgiev GA. Tear-lm-oriented

S o u r c e o f F u n d i n g
The authors received no nancial support for the research, authorship and/or publication of this article.