Joaquín Fernández1,2, Manuel Rodríguez-Vallejo1, Javier Martínez1, Ana Tauste1, Javier García-Montesinos1, David P Piñero3,4. 1. Department of Ophthalmology (Qvision), Vithas Virgen del Mar Hospital, 04120, Almería, Spain. 2. Department of Ophthalmology, Torrecárdenas Hospital Complex, 04009, Almería, Spain. 3. Department of Optics, Pharmacology and Anatomy, University of Alicante, Alicante, Spain. david.pinyero@ua.es. 4. Department of Ophthalmology (OFTALMAR), Vithas Medimar International Hospital, Alicante, Spain. david.pinyero@ua.es.
Abstract
PURPOSE: To assess the agreement and repeatability of two objective systems for measuring the tear film stability. METHODS: Retrospective analysis of the tear film stability of 99 healthy right eyes measured with a videokeratoscope (VK) and the Optical Quality Analysis System (OQAS, Visiometrics). Two consecutive measures were taken with both systems, with an interval of 10 min between them. Variables included in the study were first and mean non-invasive break-up times (NIBUT and MNIBUT) measured with VK, and mean and standard deviation of the optical scattering index (OSIm and OSIsd) measured with OQAS. The agreement and repeatability of grading scales provided by both devices were also evaluated using the Cohen's k with quadratic weights. The Ocular Surface Disease index (OSDI) questionnaire was also passed out to all subjects. Correlations and associations between subjective and objective metrics were analyzed. RESULTS: Significant differences were found between consecutive measurements of NIBUT (p = 0.04) and MNIBUT (p = 0.01), but not for OSIm (p = 0.11) and OSIsd (p = 0.50). Grading scales resulted in fair (k = 0.20) or poor agreement (k = 0.04) between systems depending if the first or second trial was considered. The repeatability of the grading scale was good for OQAS (k = 0.59) and fair for VK (k = 0.37). No significant correlations or associations were found between OSDI and any of the metrics obtained with both devices (p ≥ 0.36). CONCLUSIONS: The two devices evaluated cannot be used interchangeably for the assessment of tear film stability. Good intrasession repeatability was obtained for tear film grading of the OQAS whereas it was fair for VK.
PURPOSE: To assess the agreement and repeatability of two objective systems for measuring the tear film stability. METHODS: Retrospective analysis of the tear film stability of 99 healthy right eyes measured with a videokeratoscope (VK) and the Optical Quality Analysis System (OQAS, Visiometrics). Two consecutive measures were taken with both systems, with an interval of 10 min between them. Variables included in the study were first and mean non-invasive break-up times (NIBUT and MNIBUT) measured with VK, and mean and standard deviation of the optical scattering index (OSIm and OSIsd) measured with OQAS. The agreement and repeatability of grading scales provided by both devices were also evaluated using the Cohen's k with quadratic weights. The Ocular Surface Disease index (OSDI) questionnaire was also passed out to all subjects. Correlations and associations between subjective and objective metrics were analyzed. RESULTS: Significant differences were found between consecutive measurements of NIBUT (p = 0.04) and MNIBUT (p = 0.01), but not for OSIm (p = 0.11) and OSIsd (p = 0.50). Grading scales resulted in fair (k = 0.20) or poor agreement (k = 0.04) between systems depending if the first or second trial was considered. The repeatability of the grading scale was good for OQAS (k = 0.59) and fair for VK (k = 0.37). No significant correlations or associations were found between OSDI and any of the metrics obtained with both devices (p ≥ 0.36). CONCLUSIONS: The two devices evaluated cannot be used interchangeably for the assessment of tear film stability. Good intrasession repeatability was obtained for tear film grading of the OQAS whereas it was fair for VK.
Authors: Kimberly L Miller; John G Walt; David R Mink; Sacha Satram-Hoang; Steven E Wilson; Henry D Perry; Penny A Asbell; Stephen C Pflugfelder Journal: Arch Ophthalmol Date: 2010-01
Authors: María García-Montero; Laura Rico-Del-Viejo; Irene Martínez-Alberquilla; Jose Luis Hernández-Verdejo; Amalia Lorente-Velázquez; David Madrid-Costa Journal: J Ophthalmol Date: 2019-07-09 Impact factor: 1.909