Pushed monocanalicular intubation. Pitfalls, deleterious side effects, and complications.

Purpose: To present our experience with pushed monocanalicular nasolacrimal intubation in the management of 90 consecutive cases of nasolacrimal outflow obstruction.

Materials And Method: This paper reports a non-randomized study of 90 consecutive cases treated with a pushed Monoka intubation system (Masterka™). A metal guide is placed inside a silicone tube rather than being attached at the distal end of the tube, as done with traditional pulled intubations. Three probe lengths are available: 30, 35, and 40 mm.

Surgical Procedure: The silicone stent was pushed into a punctum, canaliculus, and nasolacrimal duct by means of the guide. After passing through the valve of Hasner and reaching the nasal floor, the guide was then delicately withdrawn while remaining oriented along the axis of the lacrimal sac and duct. Throughout this phase, the anchoring plug was held in contact with the punctum. Three study groups were set up chronologically: group 1: endo-DCR procedures done with Masterka insertions under endoscopic observation. Group 2: Masterka insertions done with endoscopic guidance. Group 3: blind Masterka insertions without endoscopic guidance. The patients in groups 2 and 3 were selected on the information obtained by lacrimal probing. Only cases with mucosal nasolacrimal stenoses were included. All patients had surgery under general anesthesia with mechanically assisted ventilation (groups 1 and 2) or spontaneous ventilation (group 3). The anchoring plug was inserted into the punctum and vertical canaliculus, either by pulling on the probe (group 1) or using an inserting instrument.

Results: A total of 90 pushed Monoka intubations were done. Endoscopic examination (groups 1 and 2) demonstrated visually that the pushed intubation method was effective. In none of the 28 cases did the silicone bunch up when the guide was withdrawn. DEGREE OF DIFFICULTY: This was dependent upon proper selection for pushed Monoka intubation; the length of the probe and confirmation that there no false passage was created. The pushed intubation technique was only slightly more difficult than a simple lacrimal probing. The average operating time, excluding the anesthetic procedures, was respectively 5 min (group 2) and 4 min (group 3). COMPLICATIONS DURING SURGERY: There were no anesthetic or general problems observed in the three groups. Epistaxis was also not noted.

Postoperative Complications: Fifteen percent (13/90). The 13 complications noted were: two cases of canaliculitis, one intracanalicular migration, eight probes that disappeared, one keratitis, and one case of involuntary removal by the patient. DELETERIOUS SIDE EFFECTS: Tearing with the probe was in place was noted in 21.1% of the cases (19/90). This tearing disappeared as soon as the probe was removed in 50% of these cases (10/19).

Functional Results: Overall, the success rate (absence of epiphora, absence of mucous discharge) was 90% (81/90) with an average follow-up period of 19 weeks (Range, 1 day to 60 weeks). Two cases were lost to follow-up at day 1 and day 7. Group 1: 90.9% (20/22 cases; average age: 65 years, with an average follow-up period of 24 weeks). Group 2: 100% (6/6 cases; average age: 3.1 years, with an average follow-up period of 14 weeks). Group 3: 88.3% (53/60 cases excluding the two cases that were lost to follow-up; mean age: 2.3 years, with an average follow-up period of 16 weeks).

Conclusions: From a technical perspective, pushed nasolacrimal intubation is much simpler than the traditional pulled types of nasolacrimal intubation. The anesthetic procedure required is the same as that for a late probing procedure, but the functional results are better. The Masterka is an alternative to simple late probing in the treatment of mucosal nasolacrimal stenoses in patients of over 12 months of age.