The Effect of Using Blue Light Filter Feature on Smartphones with Asthenopia Occurrence

Background: Smartphone users can be found in almost every class society in Indonesia. Excessive use of smartphones and the blue light emitted by smartphones play an important role in causing asthenopia symptoms. Smartphone development companies have developed a blue light filter feature, which is expected to reduce the incidence of Asthenopia symptoms.Objective: To evaluate the Asthenopia questionnaire's comparison results before and after smartphone use with various levels of opacity in the blue light filter.Methods: This study used a quasi-experimental pre-posttest study. The research subjects were students of the Faculty of Medicine, Diponegoro University (n = 30), selected by purposive sampling. In this study, research subjects saw an hour-long smartphone with a predetermined opacity level for the blue light filter, with the same room lighting. Before and after the treatment, the subjects were asked to fill out the Asthenopia questionnaire. Data were analyzed using the Wilcoxon test, Mann Whitney U test, and Kruskal Wallis test.Results: The results of the Asthenopia questionnaire before and after using a smartphone with a blue light filter opacity level of 0% and 100% showed a significant difference in results (p <0.05), and there was no significant difference for the pre-posttest using a smartphone with a blue light filter with 50% opacity level. The comparison results of the Asthenopia questionnaire between smartphone use with the opacity level of the blue light filter 0% and 50% only showed a significant difference in sore/aching eye symptoms. The comparison results of the Asthenopia questionnaire between smartphone use with the opacity level of the blue light filter 50% and 100% only showed a significant difference in sleepy eye symptoms. The comparison results of the Asthenopia questionnaire between smartphone use with the opacity level of the blue light filter 0%, 50%, and 100%, did not show a significant difference.Conclusion: There were no significant differences between the Asthenopia questionnaire results with 0%, 50%, and 100% opacity blue light filters after one hour of smartphone use.

Airborne aerosol olfactory deposition contributes to anosmia in COVID-19

Introduction Olfactory dysfunction (OD) affects a majority of COVID-19 patients, is atypical in duration and recovery, and is associated with focal opacification and inflammation of the olfactory epithelium. Given recent increased emphasis on airborne transmission of SARS-CoV-2, the purpose of the present study was to experimentally characterize aerosol dispersion within olfactory epithelium (OE) and respiratory epithelium (RE) in human subjects, to determine if small (sub 5μm) airborne aerosols selectively deposit in the OE. Methods Healthy adult volunteers inhaled fluorescein-labeled nebulized 0.5–5μm airborne aerosol or atomized larger aerosolized droplets (30–100μm). Particulate deposition in the OE and RE was assessed by blue-light filter modified rigid endoscopic evaluation with subsequent image randomization, processing and quantification by a blinded reviewer. Results 0.5–5μm airborne aerosol deposition, as assessed by fluorescence gray value, was significantly higher in the OE than the RE bilaterally, with minimal to no deposition observed in the RE (maximum fluorescence: OE 19.5(IQR 22.5), RE 1(IQR 3.2), p<0.001; average fluorescence: OE 2.3(IQR 4.5), RE 0.1(IQR 0.2), p<0.01). Conversely, larger 30–100μm aerosolized droplet deposition was significantly greater in the RE than the OE (maximum fluorescence: OE 13(IQR 14.3), RE 38(IQR 45.5), p<0.01; average fluorescence: OE 1.9(IQR 2.1), RE 5.9(IQR 5.9), p<0.01). Conclusions Our data experimentally confirm that despite bypassing the majority of the upper airway, small-sized (0.5–5μm) airborne aerosols differentially deposit in significant concentrations within the olfactory epithelium. This provides a compelling aerodynamic mechanism to explain atypical OD in COVID-19.

Preliminary Results: The Impact of Smartphone Use and Short-Wavelength Light during the Evening on Circadian Rhythm, Sleep and Alertness

Smartphone usage strongly increased in the last decade, especially before bedtime. There is growing evidence that short-wavelength light affects hormonal secretion, thermoregulation, sleep and alertness. Whether blue light filters can attenuate these negative effects is still not clear. Therefore, here, we present preliminary data of 14 male participants (21.93 ± 2.17 years), who spent three nights in the sleep laboratory, reading 90 min either on a smartphone (1) with or (2) without a blue light filter, or (3) on printed material before bedtime. Subjective sleepiness was decreased during reading on a smartphone, but no effects were present on evening objective alertness in a GO/NOGO task. Cortisol was elevated in the morning after reading on the smartphone without a filter, which resulted in a reduced cortisol awakening response. Evening melatonin and nightly vasodilation (i.e., distal-proximal skin temperature gradient) were increased after reading on printed material. Early slow wave sleep/activity and objective alertness in the morning were only reduced after reading without a filter. These results indicate that short-wavelength light affects not only circadian rhythm and evening sleepiness but causes further effects on sleep physiology and alertness in the morning. Using a blue light filter in the evening partially reduces these negative effects.

Considerations in Management of Acute Otitis Media in the COVID-19 Era

Objectives: To present the otologic findings of a patient with COVID-19 and complicated acute otitis media, evaluate for the presence of SARS-CoV-2 in middle ear fluid, and assess whether suctioning of middle ear fluid may be aerosol- generating. Methods: The case of a man with SARS-CoV-2 infection and complicated acute otitis media with facial paralysis is presented to illustrate unique clinical decisions made in context of the COVID-19 pandemic. A cadaveric temporal bone was used to simulate droplet spread during suctioning of fluorescein-labelled middle ear fluid and visualized with a blue-light filter. Results: A 23-year-old male who presented with complicated acute otitis media with facial paralysis was found to have an acute infection with SARS-CoV-2, with positive viral PCR of nasopharyngeal swab, and a negative PCR of the middle ear fluid. He was placed on isolation precautions and treated with myringotomy, topical and systemic antibiotics, and antivirals. Consistent with observations during endonasal suctioning, suctioning of middle ear fluid was not found to be aerosol or droplet generating. Conclusion: The case of a patient with active COVID-19 presenting with complicated acute otitis media in whom middle ear fluid was sampled to evaluate the etiology of the infection and the potential middle ear predilection of SARS-CoV-2 is described. This study has implications for the clinical management of patients with both known and unknown SARS-CoV-2 infection who present with ear disease. While middle ear suctioning may not be aerosol-generating, the risk of coughing or prolonged close contact requires heightened precautions during otologic procedures in patients with suspected or confirmed COVID-19.

STUDYING NARROW-BAND BLUE LIGHT FILTER FOR WHITE LEDS

In this paper, we investigated the properties of the developed optical filter, that cuts off part of the blue light range in the spectrum of a white LED, which is harmful to the human eye. The developed filter allows reflecting up to 30 % of blue light in the range from 435 to 440 nm.