scholarly journals Repeatability and Reproducibility of Tear Film Evaporation Rate Measurement using a new Closed-Chamber Evaporimeter

2021 ◽  
Vol 15 (1) ◽  
pp. 117-121
Author(s):  
Ali A. Abusharha ◽  
Ali Al Yami ◽  
Khaled Alsreea ◽  
Raied Fagehi ◽  
Ali Alsaqr ◽  
...  

Purpose: This study evaluates the repeatability and reproducibility of tear film evaporation rate measurement using a commercially available handheld closed-chamber evaporimeter (VapoMeter, Delfin Technologies, Finland). Study Design: This was a randomized observational study, in which two visits were required. At visit 1, screening tests were performed on the participants. Subsequently, tear evaporation was measured thrice by examiner 1 (E1). The procedure was then repeated by examiner 2 (E2) at visit 2. Methods: 40 healthy participants with no ocular diseases were recruited for this study. A closed chamber evaporimeter was used in this study (VapoMeter, Delfin Technologies, Finland). Primary investigations, including slit-lamp examination, tear production test, and ocular discomfort, were performed during the first visit for the purpose of screening. Results: The mean of the three measurements of tear evaporation obtained by examiner 1 at visit 1 was 19.38 ± 0.79 g/m2/h, and the mean of the three readings obtained by examiner 2 at visit 2 was 20.49 ± 0.48 g/m2/h. The average Intraclass Correlation Coefficient (ICC) among the three readings of tear evaporation was 0.84 and 0.63 with a 95% confidence interval (CI) at visits 1 and 2, respectively. A comparison of the reliability of the measurements from the two examiners revealed an ICC of 0.69 with a 95% CI. Conclusion: The VapoMeter provides repeatable and reproducible measurements of tear film evaporation. This study demonstrates that the VapoMeter could provide clinicians with a readily available method for rapid evaluation of tear film evaporation. By considering the significance of tear evaporation as a diagnostic tool for dry eyes, the VapoMeter may help to diagnose better and manage dry eye syndrome.

2021 ◽  
Vol 15 (1) ◽  
pp. 299-304
Author(s):  
Ali Abusharha ◽  
Abdulrhman A. Shbear ◽  
Raied Fagehi ◽  
Mana A. Alanazi ◽  
Ali Alsaqr ◽  
...  

Background: The most common factor that could lead to dryness is the accelerated tear evaporation rate. Controlling the tear evaporation rate is increasingly used as a method to control dry eye complications. The present study explores the effects of different tear supplements formulations on tear film evaporation rate. Objective: This study aimed to evaluate the short-term effects of Systane ULTRA and Artelac Advanced eye drops on the tear film evaporation rate. Methods: Fifteen male dry eye subjects were enrolled in the current study. Tear film parameters were observed at several time points post installation (10, 20, 30, and 60 min). The tear film parameters observed in the current study were tear evaporation rate, noninvasive breakup time (NITBUT) and tear meniscus height (TMH). Two visits were required to conduct this study. One visit was conducted to assess the physiological tear film parameters with the use of Systane® ULTRA eye drop. The other visit was conducted to assess tear film parameters with the use of Artelac Advanced eye drop. Results: The mean tear evaporation rate at baseline was 52.58 ± 23.24 g/m2 h. A box plot of tear evaporation showed a reduction in tear film evaporation rate after instillation of Systane eye drop. A drop in tear film evaporation rate of 14% was observed at 20 and 60 min time point after instillation of Systane ULTRA eye drop. A significant increase in NITBUT was found after instillation of Systane ULTRA (P = 0.01) and Artelac Advanced (P = 0.02). Conclusion: The current study indicates a significant improvement in the tear film parameters using both HP-Guar and hyaluronic acid formulations. However, it was apparent that the use of HP-Guar was superior to hyaluronic acid in controlling the tear evaporation rate in dry eye subjects.


2021 ◽  
Vol 8 ◽  
Author(s):  
Yunru Liao ◽  
Zhenlan Yang ◽  
Zijing Li ◽  
Rui Zeng ◽  
Jing Wang ◽  
...  

Purpose: Purpose of this study is to evaluate the measuring consistency of central refraction between multispectral refraction topography (MRT) and autorefractometry.Methods: This was a descriptive cross-sectional study including subjects in Sun Yat-sen Memorial Hospital from September 1, 2020, to December 31, 2020, ages 20 to 35 years with a best corrected visual acuity of 20/20 or better. All patients underwent cycloplegia, and the refractive status was estimated with autorefractometer, experienced optometrist and MRT. We analyzed the central refraction of the autorefractometer and MRT. The repeatability and reproducibility of values measured using both devices were evaluated using intraclass correlation coefficients (ICCs).Results: A total of 145 subjects ages 20 to 35 (290 eyes) were enrolled. The mean central refraction of the autorefractometer was −4.69 ± 2.64 diopters (D) (range −9.50 to +4.75 D), while the mean central refraction of MRT was −4.49 ± 2.61 diopters (D) (range −8.79 to +5.02 D). Pearson correlation analysis revealed a high correlation between the two devices. The intraclass correlation coefficient (ICC) also showed high agreement. The intrarater and interrater ICC values of central refraction were more than 0.90 in both devices and conditions. At the same time, the mean central refraction of experienced optometrist was −4.74 ± 2.66 diopters (D) (range −9.50 to +4.75D). The intra-class correlation coefficient of central refraction measured by MRT and subjective refraction was 0.939.Conclusions: Results revealed that autorefractometry, experienced optometrist and MRT show high agreement in measuring central refraction. MRT could provide a potential objective method to assess peripheral refraction.


2018 ◽  
Vol 95 (1) ◽  
pp. 5-12 ◽  
Author(s):  
Thomas J. Dursch ◽  
Wing Li ◽  
Baseem Taraz ◽  
Meng C. Lin ◽  
Clayton J. Radke

2020 ◽  
Vol 104 (10) ◽  
pp. 1373-1377
Author(s):  
Jacqueline Tan ◽  
Tianni Jia ◽  
Roslyn Liao ◽  
Fiona Stapleton

AimTo evaluate the effects of a proprietary formulated eye drop with Leptospermum spp honey versus a conventional lubricant eye drop on tear film properties in subjects with symptoms related to dry eye disease after 28 days of treatment.MethodsForty-six subjects with symptoms related to dry eye (Ocular Surface Disease Index (OSDI) score >12) were enrolled and randomly assigned to receive either the test formulated eye drop (Optimel by Melcare Biomedical Pty Ltd) or control eye drops (Alcon, USA) in this double-masked study. Inferior lipid layer thickness (LLT), tear film evaporation rate (TER), fluorescein tear film break-up time (TBUT), corneal staining and subjective symptoms (OSDI and visual analogue scales (VAS)) were measured before and after 28 days of instilling the eye drops.ResultsForty-two subjects completed the study (21 subjects in each group). After 28 days of treatment, TER showed a significantly greater reduction with the formulated eye drop compared with the control (p=0.01). TBUT showed a slight but not statistically significant increase with the formulated eye drop compared with the control (p=0.06), and a significantly greater reduction (improvement) in OSDI scores was observed with the formulated eye drop compared with the control (p=0.01). No significant differences were found between the two groups for inferior LLT, corneal staining and any of the VAS scores.ConclusionsThe formulated eye drops were effective in reducing tear film evaporation rate and were more effective for improving symptoms of dry eye compared with the control eye drops after 28 days of treatment.Trial registration numberNCT03622619.


2015 ◽  
Vol 2015 ◽  
pp. 1-6 ◽  
Author(s):  
Jinhai Huang ◽  
Giacomo Savini ◽  
Chengfang Wang ◽  
Weicong Lu ◽  
Rongrong Gao ◽  
...  

Purpose.To assess the reliability and comparability of measuring central corneal thickness (CCT) and thinnest corneal thickness (TCT) using a new Scheimpflug-Placido analyzer (TMS-5, Japan) and ultrasound (US) pachymetry.Methods.Seventy-six healthy subjects were prospectively measured 3 times by 1 operator using the TMS-5, 3 additional consecutive scans were performed by a second operator, and ultrasound (US) pachymetry measurements were taken. The test-retest repeatability (TRT), coefficient of variation (CoV), and intraclass correlation coefficient (ICC) were calculated to evaluate intraoperator repeatability and interoperator reproducibility. Agreement among the devices was assessed using Bland-Altman plots and 95% limits of agreement (LoA).Results.The intraoperators TRT and CoV were <19 μm and 2.0%, respectively. The interoperators TRT and CoV were <12 μm and 1.0%, respectively, and ICC was >0.90. The mean CCT and TCT measurements using the TMS-5 were 15.97 μm (95% LoA from −26.42 to −5.52 μm) and 20.32 μm (95% LoA from −30.67 to −9.97 μm) smaller, respectively, than those using US pachymetry.Conclusions.The TMS-5 shows good repeatability and reproducibility for measuring CCT and TCT in normal subjects but only moderate agreement with US pachymetry results. Caution is warranted before using these techniques interchangeably.


2015 ◽  
Vol 2015 ◽  
pp. 1-6 ◽  
Author(s):  
Ayaka Iijima ◽  
Kimiya Shimizu ◽  
Hidenaga Kobashi ◽  
Aya Saito ◽  
Kazutaka Kamiya

Purpose. To assess the repeatability, reproducibility, and comparability of measurements of subjective and objective forward scattering in healthy subjects.Methods. We prospectively examined twenty eyes of 20 healthy volunteers (7 men and 13 women; ages, 28.4 ± 4.1 years). The logarithmic straylight value (log(s)) and the objective scattering index (OSI) were measured with a straylight meter (C-Quant) and a point-spread function meter (OQAS), respectively.Results. The 95% limits of agreement (LoA) between first and second measurements ranged from −0.211 to 0.207 for the C-Quant and from −0.302 to 0.477 for the OQAS. The intraclass correlation coefficients for the repeatability of the log(s) and OSI measurements were 0.815 and 0.926, respectively. The mean difference between examiners was −0.051 ± 0.133 (95% LoA; −0.311 to 0.209) for the C-Quant and 0.080 ± 0.307 (−0.522 to 0.682) for the OQAS. There was a modest, but significant, correlation between the log(s) and the OSI (Spearman correlation coefficientr=0.498,p=0.026).Conclusions. The C-Quant and the OQAS provide good repeatability and reproducibility, although the OQAS measurement provides a slightly higher ICC than the C-Quant measurement. The subjective forward scattering may be to some extent expressed in the objective forward scattering in healthy subjects.


2020 ◽  
Vol 29 (2) ◽  
pp. 259-264 ◽  
Author(s):  
Hasan K. Saleh ◽  
Paula Folkeard ◽  
Ewan Macpherson ◽  
Susan Scollie

Purpose The original Connected Speech Test (CST; Cox et al., 1987) is a well-regarded and often utilized speech perception test. The aim of this study was to develop a new version of the CST using a neutral North American accent and to assess the use of this updated CST on participants with normal hearing. Method A female English speaker was recruited to read the original CST passages, which were recorded as the new CST stimuli. A study was designed to assess the newly recorded CST passages' equivalence and conduct normalization. The study included 19 Western University students (11 females and eight males) with normal hearing and with English as a first language. Results Raw scores for the 48 tested passages were converted to rationalized arcsine units, and average passage scores more than 1 rationalized arcsine unit standard deviation from the mean were excluded. The internal reliability of the 32 remaining passages was assessed, and the two-way random effects intraclass correlation was .944. Conclusion The aim of our study was to create new CST stimuli with a more general North American accent in order to minimize accent effects on the speech perception scores. The study resulted in 32 passages of equivalent difficulty for listeners with normal hearing.


2021 ◽  
Vol 7 (1) ◽  
Author(s):  
Aristeidis A. Villias ◽  
Stefanos G. Kourtis ◽  
Hercules C. Karkazis ◽  
Gregory L. Polyzois

Abstract Background The replica technique with its modifications (negative replica) has been used for the assessment of marginal fit (MF). However, identification of the boundaries between prosthesis, cement, and abutment is challenging. The recently developed Digital Image Analysis Sequence (DIAS) addresses this limitation. Although DIAS is applicable, its reliability has not yet been proven. The purpose of this study was to verify the DIAS as an acceptable method for the quantitative assessment of MF at cemented crowns, by conducting statistical tests of agreement between different examiners. Methods One hundred fifty-one implant-supported experimental crowns were cemented. Equal negative replicas were produced from the assemblies. Each replica was sectioned in six parts, which were photographed under an optical microscope. From the 906 standardized digital photomicrographs (0.65 μm/pixel), 130 were randomly selected for analysis. DIAS included tracing the profile of the crown and the abutment and marking the margin definition points before cementation. Next, the traced and marked outlines were superimposed on each digital image, highlighting the components’ boundaries and enabling MF measurements. One researcher ran the analysis twice and three others once, independently. Five groups of 130 measurements were formed. Intra- and interobserver reliability was evaluated with intraclass correlation coefficient (ICC). Agreement was estimated with the standard error of measurement (SEM), the smallest detectable change at the 95% confidence level (SDC95%), and the Bland and Altman method of limits of agreement (LoA). Results Measured MF ranged between 22.83 and 286.58 pixels. Both the intra- and interobserver reliability were excellent, ICC = 1 at 95% confidence level. The intra- and interobserver SEM and SDC95% were less than 1 and 3 pixels, respectively. The Bland–Altman analysis presented graphically high level of agreement between the mean measurement of the first observer and each of the three other observers’ measurements. Differences between observers were normally distributed. In all three cases, the mean difference was less than 1 pixel and within ± 3 pixels LoA laid at least 95% of differences. T tests of the differences did not reveal any fixed bias (P > .05, not significant). Conclusion The DIAS is an objective and reliable method able to detect and quantify MF at ranges observed in clinical practice.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Manjot Kaur Grewal ◽  
Shruti Chandra ◽  
Alan Bird ◽  
Glen Jeffery ◽  
Sobha Sivaprasad

AbstractTo evaluate the effect of aging, intra- and intersession repeatability and regional scotopic sensitivities in healthy and age-related macular degeneration (AMD) eyes. Intra- and intersession agreement and effect of age was measured in healthy individuals. The mean sensitivity (MS) and pointwise retinal sensitivities (PWS) within the central 24° with 505 nm (cyan) and 625 nm (red) stimuli were evaluated in 50 individuals (11 healthy and 39 AMD eyes). The overall intra- and intersession had excellent reliability (intraclass correlation coefficient, ICC > 0.90) and tests were highly correlated (Spearman rs = 0.75–0.86). Eyes with subretinal drusenoid deposit (SDD) had reduced PWS centrally, particularly at inferior and nasal retinal locations compared with controls and intermediate AMD (iAMD) without SDD. There was no difference in MS or PWS at any retinal location between iAMD without SDD and healthy individuals nor between iAMD with SDD and non-foveal atrophic AMD groups. Eyes with SDD have reduced rod function compared to iAMD without SDD and healthy eyes, but similar to eyes with non-foveal atrophy. Our results highlight rod dysfunction is not directly correlated with drusen load and SDD location.


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