Generation of a novel rabbit model for meibomian gland dysfunction

Abstract

Purpose : To generate an MGD model using chemical cauterization and to compare the structural and functional alterations with an electrocauterized MGD model

Methods : This experimental animal study includes eight New Zealand white rabbits. The Meibomian gland orifices of the upper and lower eyelid of the left eye were subjected to chemical cautery (CC) using 1M NaOH (n=4) or electrocautery (EC) (n=4), taking right eye as control. Alterations in the tear film, corneal surface and meibomian glands were evaluated by performing Schirmers test and non-invasive tear film break up time (NITBUT), tear meniscus height (TMH) and meibography using keratography-5M (Oculus,Wetzlar,Germany) on Day 7, 14, 30, 60 and 90. Structural alterations in the eyelids and meibomian glands were evaluated by histopathological examination at day 30 and 90 in both the groups (n=2).

Results : The average tear film metrics at baseline were 21 ± 1.76, 0.43 ± 0.06, 12.88 ± 2.08 for Schirmer’s test, TMH, and NITBUT respectively. A significant increase in Schirmer’s and TMH values was noted at Day 7 (p<0.03) following intervention and no significant difference from baseline was noted in the subsequent follow ups in both the groups. NITBUT showed significant reduction by day 30 (p<0.02) which persisted at day 60 (p<0.02) and 90 (p<0.02) in both the groups. Meibography showed areas of partial and complete gland dropouts on day 30, 60 and 90 in both the groups. Histopathological examination revealed appearance of structural changes like epithelial hyperplasia, keratinization, duct dilatation and acinar atrophy of the adjacent meibomian glands by day 30 that got established by day 90 in both the groups. The mean ductal dilatation of meibomian glands on histological sections stained with hematoxylin and eosin at day 90 was 1321 ± 46.5m and 1121 ± 337.2 min in CC and EC group respectively. The histopathological changes at day 90 were more marked in the CC group as compared to EC group.

Conclusions : Chemical cauterization is a simple, cost-effective, equipment independent method to successfully induce MGD rabbit model. The alterations in the tear film induced by this model were similar in both chemical and electrocauterization models.

This abstract was presented at the 2023 ARVO Annual Meeting, held in New Orleans, LA, April 23-27, 2023.