Abstract
Purpose :
Create a model of evaporative dry eye or meibomian gland dysfunction in the rabbit via closure of meibomian glands, building on the Gilbard et al.’s previous work.
Methods :
Six (6) New Zealand White rabbits were divided into two equal groups. Meibomian gland closure was achieved by cauterization of either alternating (Group 1) or all (Group 2) meibomian glands orifices in upper and lower eyelid of right eyes (OD), while left eyes (OS) were left untreated. Two (2) animals served as a control (no cauterization in either eye). Tear break-up time (TBUT) and tear production were measured on Day -2 and Day -1 (baseline), and slit lamp evaluations were performed prior to cauterization. Animals were followed for five weeks, with daily clinical observations (Draize score), weekly measurements of TBUT, tear production, and slit lamp evaluation prior to termination at Day 35.
Results :
Clinical observations revealed eschar formation and swelling of the eyelids post cauterization that completely resolved at three weeks. Fluorescein staining did not reveal any corneal epithelial defect. There were no consistent differences in tear production between eyes or between time points in either group during the study. Cauterization of all meibomian gland orifices (Group 2) resulted in a consistent decrease in TBUT relative to baseline or untreated eye (Baseline Day -1 TBUT: 10.3 ± 1.5 sec in OD and 12.7 ± 2.1 sec in OS), which was significant at Day 14 (TBUT: 8.7 ± 1.5 sec in OD and 16.3 ± 2.1 sec in OS), Day 21 (TBUT: 7.7 ± 1.5 sec in OD and 15.7 ± 1.5 sec in OS) and Day 28 (TBUT: 8.7 ± 4.2 sec in OD and 16.7 ± 0.6 sec in OS), p= 0.039. Histopathological evaluation of eyes (sacrificed at Day 35) including eyelids, lacrimal, harderian, and meibomian glands did not reveal any significant findings.
Conclusions :
Cauterization of all meibomian glands of rabbits yielded a significant reduction in tear film stability after 2 weeks and through 28 days. This model may be further optimized to serve as a tool to screen formulations for their ability to restore tear film stability and alleviate evaporative dry eye condition.
This is a 2021 ARVO Annual Meeting abstract.