[Endonasal dacryocystorhinostomy (DCR) with protected drill]

To analyze the interest of protected drills to perform endoscopic endonasal DCR.[corrected] Fifty patients suffering from chronic epiphora were operated successively. None of those patients had had prior nasal surgery. The same surgeons (BF and ER) did the surgical procedure for all the cases. The technical steps were: endoscopic visualization of the middle meatus and evaluation of the anatomic variations of the nose; identification of the lacrymal bag with a 1 mm light in the canaliculus; unciformectomy; the maxillary bone was drilled with a 3.2 mm bit (straightshot Xomed), protected and irrigated; the lacrymal bag was opened by cissors and the flap was pushed in the ethmoid and coagulated.The suction-irrigation system was efficient to clean the surgical site, with a good endoscopic control. The protected bit didn't damage the 4-mm optics and the septal wall mucosa, even in narrow noses. The staightshot bit (Xomed) was tough enough to drill the maxillary bone in only 68 % of the surgical cases. In 28 % the drilling was unsatisfactory and in 4 % it was inefficient. The functional results at 6 month were good in 85 %. There was no difference between normal and narrow noses.The concept of protected bits perfectly matches the endoscopic endonasal DCR. The visual comfort and security of the surgical procedure are increased. Short term results are equivalent to external DCR, but are rather inefficient and expensive.