The tear function in electronic cigarette smokers

SIGNIFICANCE Prominent ocular surface dryness and poor tear film quality among electronic cigarette (e-cigarette) smokers (or vapers) indicate potential harm to the eyes from vaping. These findings may serve as precautionary signs for e-cigarette users and exposed bystanders. PURPOSE Little is known about the effect of e-cigarettes on the eyes except for reported eye irritation among individuals who were exposed to e-cigarette vapors and e-liquids. This study aims to investigate the effect of vaping on ocular surface health of long-term vapers. METHODS Twenty-one vapers and 21 healthy nonsmokers who are all male underwent measurements of the Ocular Surface Disease Index, noninvasive tear breakup time, fluorescein breakup time, ocular surface staining, tear meniscus height, and the Schirmer test. The effect of voltage used during vaping was also evaluated against the measurements. RESULTS Vapers experienced moderate-to-severe eye dryness (25.0 [interquartile range, 14.6 to 43.7]) as indicated by the Ocular Surface Disease Index. Significant reductions of noninvasive tear breakup time (3.13 ± 0.97 vs. 6.57 ± 2.31 seconds; P < .0001), fluorescein breakup time (2.68 [interquartile range, 2.33 to 3.18] vs. 4.12 [3.56 to 5.07] seconds; P < .0001), and tear meniscus height (203.0 [193.0 to 225.5] vs. 235.0 [210.0 to 253.50] μm; P = .002) were noted in vapers, but the Schirmer test showed higher results (14.5 [12.0 to 17.0] vs. 8.0 [7.0 to 11.0] mm; P = .001) compared with nonsmokers. Increase in vaping voltage aggravated the dry eye symptoms and tear instability (P < .05). Higher Schirmer test result was also noted as voltage increases. CONCLUSIONS Vapers showed moderate-to-severe symptomatic dry eye and poorer tear film quality compared with nonsmokers. High vaping voltage may have aggravated the dry eye syndrome because of hazardous by-products from pyrolysis of the e-liquid constituents. Investigation of the ocular surface health at cellular and molecular levels is warranted to gain a deeper understanding on the effect of e-cigarette to the eyes

Temporal characteristics of sodium fluorescein in the tear meniscus

Purpose To observe the emission intensity profile of sodium fluorescein in the human tear film as a function of time and concentration. Methods Twenty-two participants with no dry eye signs or symptoms were randomly allocated to receive 1 μL of either a 2 or 10% concentration of fluorescein to one eye. Images of the inferior tear meniscus were captured at regular intervals over 30 minutes and the process repeated for the other eye with the alternate concentration. Fluorescence intensity was quantified on the basis of the grayscale pixel values in the tear meniscus images. The fluorescein-decay profile over time and between concentrations was determined. Results Peak fluorescence intensity was reached in 3.9 ± 3.0 and 8.7 ± 4.4 minutes after instillation for the 2 and 10% concentrations, respectively. The 10% concentration of fluorescein maintained its peak fluorescence intensity longer than the 2% concentration (about 9 and 2 minutes, respectively). The peak fluorescence intensity was not significantly different between the higher and lower concentrations (44 ± 37 vs. 38 ± 32 units, P = .22). For both concentrations, the observed intensity did not return to baseline levels by the end of the 30-minute observation time. Conclusions The fluorescence intensity of fluorescein in a clinical setting varies with time such that both the onset and duration of maximum brightness are concentration dependent. At low concentration (2%), maximum brightness occurs almost immediately after instillation and lasts about 2 minutes. With a higher concentration (10%), the effective working window is delayed for about 7 to 8 minutes. Irrespective of initial concentration, observable fluorescence remains in the tear film beyond 30 minutes post-instillation

Computer vision syndrome and blue light filtering lens wear in architecture community

INTRODUCTION: Computer vision syndrome (CVS) is a multifaceted condition, displaying range of ocular and visual symptoms. To curb CVS, blue light filtering lens (BLFL) wear is promoted in reducing chronic radiation exposure from digital devices, reported to damaging the eyes. Nonetheless, the efficacy of BLFL is equivocal. This study aims to explore the influence of BLFL on CVS among architecture personnel – a susceptible community due to their work. METHODS: Student and professional architects provided info on computer exposure, awareness on CVS, ergonomic practices, and BLFL wear through a cross-sectional survey. CVS is identified when CVS-Q questionnaire score is ≥6. Chi-square and logistic regression analyses were used to identify the factors influencing the condition. RESULTS: Of 209 respondents, 43.5% were identified with CVS. The student and professional architects suffered from CVS similarly in prevalence (45.2%, n=42 vs. 42.2%, n=49) and severity suggested by the CVS-Q score (Median= 13.5 [interquartile range= 8.0─19.7] vs. 13.0 [8.50─15.0]). Sixty-eight percent with CVS indicated wearing BLFL, yet no significant effect was found with the non-wearing group (P=0.491). CVS is more likely to worsen by longer computer use (Odds ratio=3.80; 95% CI, 2.28─6.32; P 4 hours. Only 19.6% of them taking frequent breaks while working. CVS was also influenced by the lack of awareness on visual hygiene 20-20-20 rule (P=0.017). DISCUSSION: The notion of BLFL wear in reducing CVS requires cautious interpretation. Instead, taking frequent breaks could curb CVS as longer duration of computer use aggravated the condition. The 20-20-20 rule is a recommended visual hygiene practice to prevent CVS. It entails taking a 20-second break for every 20 minutes of computer use by looking at far (20 feet). As student and professional architects suffered from CVS similarly, imparting awareness on CVS and visual hygiene practices in architecture education is crucial to prevent the condition when working

The Impact of E-Cigarette Smoking and Vaping Voltage on Tear Film

Background: The impact of e-cigarette (EC) vaping to the eyes is not much known except for reported eye irritation from exposure to EC vapor and e-liquid. Dubbed as “healthier” version of smoking due to lesser toxicants compared to conventional cigarette, studies found that e-liquid product label often do not represent the actual components. Carcinogens and free radicals were also found in EC vapor and they were associated with e-liquid compositions, device power output, and puffing profile. This study aims to investigate the effect of vaping on tear film and ocular comfort of long-term vapers. Methodology: Twenty-one vapers and 21 non-smokers (age range: 18 -30 years old) were evaluated on their Ocular Surface Disease Index (OSDI) score, non-invasive tear break-up time (NITBUT), fluorescein break-up time (FBUT), tear meniscus height (TMH), and Schirmer test. The influence of regular vaping voltage was assessed against the parameters. Results: The OSDI score shows vapers experienced moderate-to-severe eye dryness [25.0 (IQR 14.6—43.7)]. Significantly lower NITBUT (P < .0001, r = 0.70), FBUT (P < .0001, r = -0.76), and TMH (P = .002, r = -0.40) but higher Shirmer test score (P = .001, r = -0.49) were found in vapers compared with non-smokers. Increase in vaping voltage deteriorate the dry eye symptoms and tear stability (P < .05). Higher Schirmer test result was also noted as voltageincreases. Conclusion: Moderate-to-severe ocular discomfort and poor tear film function among vapers signaled disadvantages of vaping to the eyes. Exposure to the by-products of e-liquid pyrolysis during high voltage vaping may have deteriorated the tear function. Investigation on other ocular surface health parameters is necessary to gain a deeper understanding on the impact of vaping to the eyes

The potential of nigella sativa and thymoquinone in salvaging the embryo from effects of toxic paternal exposure

Objectives/Research Problem: Studies have reported that exposure to the alkylating drug, cyclophosphamide (CPA), for cancer treatment results in adverse reproductive consequences. Over-production of reactive oxygen species causes oxidative stress thus affecting the DNA in male germ cell inducing sperm defects. Our goal is to assess the potential of Nigella sativa extract (NSE) and thymoquinone (TQ) in the enhancement of sperm and embryo quality following exposure to the damaging effects of the anticancer drug. Materials and Method: Thirty male ICR mice were divided into six groups; Group 1: Vehicle-treated control (normal saline), Group 2: CPA-only, Group 3: TQ-only, Group 4: NSE-only, Group 5: CPA followed by TQ and Group 6: CPA followed by NSE. CPA is a one-time administration at a dose of 200 mg/kg via intraperitoneal injection. Both NSE and TQ were administered at 10 mg/kg on alternate days either on their own or in the combination with CPA. Animals were sacrificed at 33 days by cervical dislocation and sperm from caudal epididymis were taken for analysis, followed by in vitro fertilization (IVF) with the eggs from untreated female ICR mice. Fertilization rates and embryo development were assessed and monitored for 5 days. Results and Discussion: Results showed that NSE and TQ supplementation to CPA-exposed male mice have no significant effect (p>0.05) on the total number of sperm. NSE and TQ supplementation have been shown to have significant effect (p<0.05) on the percentage of motile sperm as well as the number of abnormal sperm. Four types of abnormalities of the sperm were found which include folded sperm, amorphous, banana-like and the lack of usual hook. Embryo quality showed a significant improvement following supplementation of TQ and NSE (p<0.05). Conclusion: Overall, both NSE and TQ have indicated chemo-preventive potential against the cytotoxicity of CPA on reproductive capacity and fertility in mice