STENOSIS OF THE I.ACHRYMO-NASAI, DUCT. 



Obliteration of the lachrymal duct may occur from stricture of 

 the canal, the result of wounds or other irritants : from pres- 

 sure by the inflamed mucosa in nasal catarrh, or strangles : from 

 polypus or osseous tumor in the nose : from actinomycosis or 

 other disease of the Bones. 



The one manifest symptom is the escape of the tears on to 

 the face. To complete the diagnosis, injection of one punctum 

 will cause distension of the lachrymal sac. 



Treatment. This may be attempted by bougies. In the horse 

 a small sound, metallic or whalebone bougie, thoroughly sterilized 

 and smeared with aseptic vaseline, or oil, is inserted from the 

 nasal opening and carefully passed on into the sac. In the dog 

 the nasal opening cannot be reached and the bougie must be 

 passed by the puncta and lachrymal sac. To secure the requisite 

 dilation, it is usually necessary to probe the passage daily, using 

 a larger probe when the first passes easily, until the canal has 

 been sufiiciently dilated. 



A second resort is to distend the canal by a liquid injection 

 thrown into the nasal opening. This will succeed when the ob- 

 struction is only caused by concretions in the canal. 



A somewhat similar resort is the insufflation of the duct by 

 means of a finely pointed tube inserted from below into the nasal 

 orifice of the duct. 



Still another method is to make a new opening for the escape 

 of the tears into the nose. When the stenosis is at or near the 

 nasal opening of the duct, an artificial opening is easily made and 

 usually satisfactory. Under anaesthesia, . a sterilized silver 

 probe is passed through the upper punctum, the sac and 

 canal. When it meets definite obstruction its position is ascer- 

 tained inside the nose, and an incision is made so as to allow its 

 escape. The constant escape of tears tends to prevent it from 

 closing up again, but it is well to examine into this until it 

 has thoroughly healed. A silk thread worn in the duct and 

 held in place by a copper or aluminum ring on each end may be 

 resorted to. 

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