End-to-side Anastomosis for Obstruction of the Naso-lacrimal Duct.

IN all the operations commonly performed for obstruction of the nasolacrimal duct, the side of the sac, and not the end, is used for the anastomosis (Fig. 1). The medial wall of the sac is incised vertically over the greater part of its extent to provide the anterior and posterior flaps. This radically alters the anatomy and destroys any chance of pumping action by the orbicularis. The upper end of the sac, in which lie the opening of the common canaliculus and the mucous folds which guard it, is laid open and left in close proximity to the raw upper edge of the bony opening. Gaps are left above and below the anastomosis unlined by mucous membrane, extensive removal of bone is necessary in the course of which ethmoid cells may be entered, and the anterior and posterior suture lines are liable to adhere-all features which favour obstruction of the anastomosis by granulation and fibrous tissue. These operations are mostly modifications of the flap technique introduced by Dupuy-Dutemps and Bourguet (1921); they work well on the whole, but failures still occur in some 5 to 10 per cent. of cases and imperfect results in a larger number, which must be attributed, at least in part, to the defects of the method. The end of the naso-lacrimal duct normally opens into the side of the nose (Fig. 2). It therefore seems logical, when the duct is obstructed, to excise the obstruction (Fig. 3) and to join the proximal cut end once more to the side of the nose making an accurate anastomosis with a circular hole in the mucosa (Fig. 4). In this way the only change produced is that the duct opens into the nose somewhat higher than before. The anatomy of the upper part of the sac is unaffected, there are no gaps unlined by mucous membrane, the bony hole is small, leaving the ethmoidal cells untouched, and the suture lines cannot adhere because the opening is circular. Such a procedure may be called end-to-side anastomosis.