Micro-endoscopy of the lacrimal apparatus combined with Erbium YAG laser: an anatomical study. New methods of imaging]

PURPOSE: To study the anatomic structure and the endoscopic aspect of the lacrimal drainage system and to evaluate the efficacy of the Erbium laser with microendoscope in lacrimal obstruction. METHODS: Twenty lacrimal ducts from ten fresh cadaver heads were used to lead a special rigid probe of 1.1. mm diameter (Endognost Schwind). This probe combined a flexible endoscopic probe of 500 mu, an Erbium laser fiber of 375 mu and an irrigation. The probe was introduced through the inferior canaliculus. Progressing in the lacrimal system, all the images were analysed. Then, we used the laser fiber to open the lacrimal sac mucosa and the lacrimal bone. RESULTS: The anatomo-endoscopic analysis was performed using endoscopic data. We appreciated essentially the walls of valves and sinuses that appeared only functional when increasing the irrigation flow. The laser could easily open the mucosa and the lacrimal bone but not the maxilla. DISCUSSION: The small size of the cannula allows to use the system for the diagnosis of lacrimal obstructions. The combined laser allows to treat at same time canalicular obstructions and lower obstructions. CONCLUSION: The endocanalicular study of the lacrimal drainage system can diagnose the type of obstruction and can treat it. A clinical study is requested to confirm these results.