Noninvasive high-contrast in vivo imaging of conjunctival goblet cell using moxifloxacin-based fluorescence microscopy in a rabbit model with ocular surface damage induced by 0.2% benzalkonium chloride.

Abstract

Purpose : To investigate the non-invasive examination of conjunctival goblet cells (GCs) by moxifloxacin-based fluorescence microscopy (MBFM) in a rabbit model with ocular surface damage (OSD) induced by 0.2% Benzalkonium Chloride (BAC)

Methods : Moxifloxacin-based axially swept wide-field fluorescence microscopy, which can image the conjunctiva with 2.0-μm resolution, 1.2 × 1.2 mm field of view, 2.2-mm depth of field, and 1-fps imaging speed, was used in the study. Four control and eight OSD rabbits were used. For the OSD rabbit model, 0.2% BAC was topically instilled once daily to one eye of each rabbit for 7 days. The same procedure was performed in the control group using Balanced Salt Solution (Alcon, Fort Worth, TX) instead of BAC. MBFM imaging of the superior bulbar conjunctiva was conducted after topical instillation of moxifloxacin 0.5% ophthalmic solution (Vigamox^®; Alcon). The imaging was conducted longitudinally every 7 days for 21 days and the changes of GC density were analyzed. Clinical examinations, including fluorescein staining and tear film break-up time (TBUT), were conducted together to measure dry eye severity.

Results : In-vivo GC imaging of rabbits was possible without significant motion artifacts. Longitudinal MBFM imaging of the BAC-induced OSD rabbit model showed significant GC density loss at days 7 (447±246 GCs/mm²) and 14 (470±260 GCs/mm²) post administration compared to that at the baseline (877±181 GCs/mm²) and their recovery at day 21 (833±437 GCs/mm²). The GC density of control rabbits was unchanged during the longitudinal MBFM imaging for 3 weeks. The corneal staining score and TBUT significantly worsened at days 7 (8.1±2.2, 3.4±1.5 s, respectively) and 14 (6.4±1.6, 4.3±1.3 s, respectively) compared to those at the baseline (1.8±0.5, 6.8±1.6 s, respectively), and had recovered on day 21 (0.8±0.9, 8.4±1.2 s, respectively). They showed strong correlations with GC density.

Conclusions : MBFM visualized conjunctival GCs of rabbit models non-invasively with high-contrast. In the OSD model, the changes of GC density, observed with MBFM, were correlated with clinical severity, demonstrating the potential of MBFM for clinical GC evaluation in ocular surface diseases.

This abstract was presented at the 2022 ARVO Annual Meeting, held in Denver, CO, May 1-4, 2022, and virtually.