Crawford tube placement to treat persistent nasolacrimal obstruction

   This procedure gives a better one-operation success rate for tearing and infection due to nasolacrimal obstruction which recurs after an office probing or in cases where it is clear that the anatomical obstruction is more than a simple "membrane" in the duct. Small-gauge silicone tubing is glued to metal probes which have a special ball-tipped end, allowing reasonably easy recovery in the nasal cavity. One end of the probe-tube set is placed into the upper canalicular system, advanced into the lacrimal sac, then turned downward and pushed into the nasal cavity beneath the inferior turbinate. The ball-tipped end is engaged with a special hook and the probe is pulled from the nasal cavity, dragging its attached tubing through the duct (left photo). The opposite end of the probe-tube set is introduced into the lower canalicular system and advanced into the lacrimal sac, nasolacrimal duct, and nasal cavity as previously done for the upper system. The probes are cut free of the tubing which is tied in several knots (right photo), cut short, and allowed to retract into the nasal cavity. At the conclusion of the procedure, the tubing forms a continuous loop connecting the upper and lower canalicular systems in the eyelids with the knot lying in on the floor of the nose. The tubing acts as a stent to prevent recurrent duct obstruction. It is usually removed 6 to 8 weeks following the procedure, though it may be left in place longer in some difficult cases.

   Short-term side effects may include nosebleeding and bloody tears which generally subside in the recovery area. The tube is visible at the inner corner of the eye, but it is harmless due to the inert nature of silicone. I usually prescribe an oral antibiotic to use for 10 days following the procedure.  Occasionally, the tube will extrude, looping in front of the eye or even onto the cheek, requiring earlier-than-anticipated removal. Even when this occurs, the problem is usually cured and the tube does not need to be replaced. Some surgeons sew the tube into the nose to prevent premature extrusion, but this can make office removal difficult, requiring another anesthetic when the tube has to be removed.