Abstract
Purpose :
To evaluate the utility of swept-source optical coherence tomography (SS-OCT) to objectively image and grade the degree of anterior chamber (AC) inflammation.
Methods :
In this IRB-approved, prospective, observational study, we enrolled 29 eyes from 23 patients with AC-involving uveitis. The severity of AC inflammation was performed by an experience uveitis specialist (OLL) using the Standardization of Uveitis Nomenclature (SUN) criteria (0,0.5+, 1+,2+,3+,4+). Swept source OCT imaging was performed using a Triton OCT (Topcon Medical Systems, Inc., Oakland, NJ) fitted with an anterior segment lens attachment. For each eye, 3-5 anterior segment (AS) B-scans (3-mm horizontal single B-scan at the central cornea) were obtained. The number of cells in the AS B-scans were quantified using two methods: (1) manual grading using the Point Picker plugin (http://bigwww.epfl.ch/thevenaz/pointpicker/ ); (2) automated grading using the Image J particle analysis algorithm (http://imagej.net/Particle_Analysis ). The number of cells among the B-scans for each eye were averaged. The automated as well as manual AC cells counts were correlated with the clinical inflammation severity score using a Spearman’s correlation.
Results :
In this cohort of 29 eyes (23 patients), the average number of AC cells on SS AS-OCT by automated analysis for each clinical grade category were 12.2 ± 5.5 SD, 57.6 ± 27.5 SD, 111.7 ± 60.0 SD, 173.6 ± 72.2 SD and 377.6 ± 92.0 SD for grades 0, 1+, 2+, 3+, and 4+, respectively. For these same clinical categories, the average manual cell counts were 8.6 ± 5.6 SD, 47.6 ± 21.2 SD, 98.2 ± 56.7 SD, 134.2 ± 55.0 SD and 231.6 ± 88.6 SD, respectively. One eye with 0.5+ clinical grade had 27 cells on SS AS-OCT measured by both methods. The range of mean AC cell numbers detected by the manual and automated methods were 2-334 and 2-475, respectively. The manual and automated cell counts were highly correlated (r=0.98, p<0.001). Both manual (r=0.88; p<0.001) and automated (r=0.89; p<0.001) methods also showed good correlation with the clinical severity grading.
Conclusions :
Quantitative AC cells counts from SS AS-OCT show good correlation with categorical clinical assessments of severity in eyes with AC-involving uveitis. This approach may provide a more precise and reliable method for monitoring uveitis and response to therapy.
This is an abstract that was submitted for the 2017 ARVO Annual Meeting, held in Baltimore, MD, May 7-11, 2017.