EVALUATION OF THE HISTOPATHOLOGICAL CHANGES IN THE LACRIMAL SAC AFTER EXPERIMENTAL OBSTRUCTION OF THE NASOLACRIMAL DUCT IN THE RABBITS

Abstract

This study was perfonned in order to evaluate the histopathological changes. that might occur in the lacrimal sac of the rabbits after experimental ligation of the nasolacrimal duct and to study the role of N.L.D. obstruction in the pathogenesis of dacryocystitis. The study was conducted on 30 adul' rabbits, weighing I-1.5 Kg; each of them was subjected to ligation of the right nasolacrimal duct under general anaesthesia using the operative microscope. The left nasolacrimal duct was left as a control. According to the duration of ligation the animals were divided into 3 groups (each contains 10 rabbits) -The first group was sacrificed lweek following ligation. -The second group was sacrificed lmonth following ligation. -The third group was sacrificed 3 months following ligation. After each group has been sacrificed, the lacrimal sac on both sides was dissected. Paraffin sections were used to study the histopathological changes in the lacrimal sac using Haematoxylin and Eosin stain The histopathological findings can be summarized as follows: In animals subjected to nasolacrimal duct obstruction for short period (1 week), the lacrimal sac showed different degrees of inflammation, ulceration, venous congestion and oedema.