AN ANIMAL-MODEL STUDYING RECONSTRUCTION TECHNIQUES AND HISTOPATHOLOGICAL CHANGES IN REPAIR OF CANALICULAR LACERATIONS

We designed an animal model using sheep to evaluate three methods of c analicular reconstruction after laceration: direct sutured reappositio n of the canaliculus without silicone intubation (4 eyelids), silicone intubation of the canalicular system with, out mucosal anastomosis (1 4 lids) and silicone intubation with mucosal anastomosis (10 lids). We also wished to determine the appropriate time of silicone tube remova l. In the canaliculi repaired using silicone intubation the tubes were removed at 4, 8 or 12 weeks. Patency of the canalicular system was as sessed at 16 weeks by probing. Sections of eyelid tissue were examined histopathologically to confirm patency and to compare the tissue alte ration caused by the various methods of repair. We found that silicone intubation was necessary to reestablish patency of the canaliculus an d that silicone intubation with and intubation without mucosal anastom osis were equally efficacious in restoring canalicular patency. The op timum time for removal of the tube was 12 weeks. Histopathologically, all canaliculi found to be patent by probing demonstrated mucosal cont inuity along the canalicular lumen.