Publication Type : Journal Article
Thematic Areas : Center for Computational Engineering and Networking (CEN), Amrita Center for Cybersecurity Systems and Networks
Source : Investigative Ophthalmology & Visual Science June 2021, Vol.62, 1426.
Url : https://iovs.arvojournals.org/article.aspx?articleid=2774667
Campus : Coimbatore
School : School of Engineering
Center : TIFAC CORE in Cyber Security
Verified : No
Year : 2021
Abstract : Purpose : In our previous study, the intensity of light scatter (ILS) from the anterior chamber was measured in cataract subjects as a measure of aqueous flare using a custom-made ocular fluorometer (TVST; 2018). While the data was sensitive, we observed a poor correlation between ILS and SUN grades for patients with mild to moderate inflammation (i.e., SUN grades 0 and 1+). To further explore the variability, we are continuing to establish the repeatability and reproducibility of ILS in uveitis patients.
Methods : Uveitis (n = 111; with SUN scores of 0 to 2+) and healthy subjects (n = 93) were included in the study. One clinician performed SUN grading. For repeatability, ILS was measured twice by the same observer. For reproducibility, ILS was recorded by two observers. We calculated the intra-observer variability (expressed as the repeatability coefficient (Rc)) and intra-class correlation coefficient (ICC) to assess intra- and inter-observer variability. The latter was further analyzed by Bland- Altman (BA) plots.
Results : The intra-observer measurements in healthy subjects revealed no statistical difference in the mean ILS (0.1480 ± 0.0700 mV; n = 93; p > 0.98). The corresponding within-subject standard deviation (Sw) is 0.0272 mV, which corresponds to a repeatability coefficient (Rc) of 0.0754 mV (= 2.77 * Sw). Uveitis patients with SUN scores of 2+ showed much higher ILS (0.3740 ± 0.1090 mV; n = 5) with Sw = 0.0418 mV, and Rc of 0.1159 mV. The inter-observer analysis with uveitis patients (n = 72 for SUN 0 and n = 8 for SUN 1) revealed an ICC of 0.63 and 0.95 for measurements with SUN grades 0 and 1, respectively. In healthy subjects (SUN grade 0), ICC was 0.73 (n = 76). Corresponding Bland-Altman plot analysis in uveitis subjects indicated 0.0044 mV and 0.0046 mV as the difference between the mean ILS between observers for SUN grades 0 and 1, respectively.
Cite this Research Publication : Sirisha Tadepalli, Hadiya Farhath Pattan, Bongoni Vishwanath, Prema Padmanabhan, Rachapalle Reddi Sudhir, Surekha Paneerselvam, Abhilash Ravi Kumar, Jyotirmay Biswas, Sangly P Srinivas "Inter and intra-observer variabilities in the measurement of aqueous flare with a custom-made ocular spot fluorometer", Investigative Ophthalmology & Visual Science June 2021, Vol.62, 1426.