Abstract
Purpose :
To evaluate the conjunctival vessel density (CVD), as a sign of inflammation, before and after treatment with a solution of Sodium Hyaluronate, Xanthan gum and osmoprotectants (HX) in mild-moderate dry eye disease (DED), and to compare it with clinical parameters: matrix metalloprotease 9 (MMP9) test, break-up time (BUT), corneo-conjunctival vital staining, Schirmer test I (STI).
Methods :
Images were acquired by Keratograph 5m (OCULUS Optikgeräte GmbH, Wetzlar, Germany) using the R-scan for automatic classification of bulbar redness (BR) and vessel-enhanced images to perform CVD analysis (Fig 1A).
Data collected before (V0) and 4 months-after treatment (V1) with HX artificial tears q.i.d.
Images were exported in TIFF format and loaded in ImageJ software. Images were normalized in terms of grayscale distribution. In order to work in the same conjunctival area, the same ovaloid area was used (Fig 1B). Then, images were binarized by using Otsu threshold. Finally, the ratio of the white pixels, corresponding to conjunctival vessels, with respect to the black pixels of the images, to obtain the CVD (Fig. 1C).
Clinical MMP9 test, BUT, SICCA score, STI were performed.
Adverse events data (burning, blurred vision) were collected.
Continuous variables (mean±standard deviation) were analyzed by using two-tailed T test and chi-square test. Statistical significance was set to p<0.05.
Results :
We collected data from 12 eyes of 12 patients. None presented adverse events.
MMP9 positivity was 66.7% at V0 and 16.7% at V1 (p=0.03); BUT was 4.6±1.4 at V0 and 5±1.3 at V1 (p=0.0001); V0 SICCA score was 2.8±1.4, and 1.2±1.1 at V1 (p<0.0001); STI was 10.7±6.9 at V0 and 12.9±7.2 at V1 (p=0.01). BR score was 0.9±0.3 at V0 and 1±0.5 at V1 (p=0.001). CVD was 0.07±0.03 at V0, resulting 0.05±0.02 at V1 (p<0.0001) (Figure 2).
Conclusions :
The HX formula was effective in improving the anatomical and functional parameters.
CVD seems to offer a more reliable method than BR in evaluating inflammation. In fact, BR score is linked to the area explored, that vary in accordance to ocular discomfort and, for this reason, resulted higher at V1. This bias is overcome calculating CVD in a fixed area. In conclusion, HX formula is effective in treating ocular surface; CVD seems promising as inflammatory marker.
This abstract was presented at the 2022 ARVO Annual Meeting, held in Denver, CO, May 1-4, 2022, and virtually.