"Pushed" monocanalicular intubation in children under general anesthesia with spontaneous ventilation. A preliminary report.

PURPOSE: We studied the possibility of placing a new type of monocanalicular nasal intubation under general anesthesia with spontaneous mask ventilation in congenital nasolacrimal duct obstruction. PATIENTS AND
METHOD: This was a non-randomized study of consecutive cases using a monocanalicular stent called the "pushed Monoka". The benefits of anchoring with meatus fixation are similar to the original Monoka device, but the probe guide or introducer is inside the silicone tube. The external diameter of the "pushed Monoka" is 0.96 mm (versus 0.64 mm in the traditional Monoka). There are three lengths: 30, 35, and 40 mm. General anesthesia was administered by inhalation of a halogen gas using a facial mask. The technique was selected by lacrimal exploration to evaluate the extent of the stenosis (simple or complex). The location and freedom of movement of the stent into the inferior nasal meatus was tested using a second lacrimal probe. Only simple stenosis cases with positive metal-to-metal contact were included in the study. INSERTION TECHNIQUE: The introducer pushes the stent into the lacrimal duct. The introducer should be removed from the silicone sleeve very carefully by gently pulling it out, millimeter by millimeter. This action is carried out while paying careful attention to keeping the stent aligned with the major axis of the lacrimal sac. Throughout this phase, the anchoring plug should remain in contact with the lacrimal punctum. Once the introducer is completely removed, the anchoring plug is secured into the vertical canaliculus. A single-use plug inserter was used.
RESULTS: Fourteen children (18 sides) with congenital nasolacrimal duct obstruction were consecutively included in the study. The pushed intubations were all performed under general anesthesia with spontaneous ventilation. The average age of the children was 26.2 months (range: 14 to 46 months). The average duration of the procedure, measured between the moment that the facial mask was put into place and the child's awakening (crying, restlessness) was 14 minutes (range: 9 to 27 minutes). The most variable parameter was the use of the venous portal. The introduction of the pushed probe itself required an average 7 minutes (range: 3 to 11 minutes). None of the children showed epistaxis. In general terms, no intraoperative or postoperative complications were noted. The "pushed Monoka" tubes were withdrawn during postoperative appointments with a mean intubation duration of 34 days (range: 1 to 59 days). Postoperative success (absence of epiphora, absence of mucous discharge) was achieved in 88% of cases (16/18 sides). The average follow-up was 8.7 weeks (range: 3 to 26 weeks). Complications and side effects were minimal. One stent was withdrawn on day 1 due to a keratitis with respect to the anchoring plug. Three stents were spontaneously lost (16%) between day 2 and day 30. Anterior rhinoscopy found none of the stents in the inferior nasal meatus. These four cases were all considered successful as there was no postoperative epiphora noted.
CONCLUSIONS: Pushed nasolacrimal intubation can be safely utilized under general anesthesia with spontaneous mask ventilation. This technique appears to be a simple and safe alternative to late and very late probing in the treatment of membranous congenital nasolacrimal duct obstruction in children older than 12 months.