Conclusion: Extra-endolaryngeal cavity puncturing with reasonable puncturing angles is an alternative method for implantation of silastic sheets when the Lichtenberger needle holder is unavailable.
Objectives: To determine reasonable extra-endolaryngeal puncturing angles for implantation of laryngeal silastic sheet and to observe the effect on treating and preventing glottic webs.
Methods: Puncture processes were conducted via extra-endolaryngeal access. For the upper puncture, the needle was inserted into the bottom of the epiglottic petiole superior to the anterior commissure through the thyrohyoid membrane. For the lower puncture, the needle was delivered into the inferior to anterior commissure (equivalent to the inferior border of the vocal cords) through the cricothyroid membrane. The upper and lower puncture angles between puncture needles and the tangential line of the thyroid cartilage were measured in 14 cadavers. Silastic sheets were implanted into laryngeal cavities in 20 patients to treat or prevent anterior glottic webs.
Results: The mean value of the upper puncture angle was 30° (range 23.5-39°) while the lower puncture angle was also 30° (24-40°). Surgery procedures for implanting silastic sheets succeeded in 20 patients by extra-endolaryngeal puncture access. The average numbers of upper and lower punctures were 2 and 1.6, respectively. At follow-up none of the 20 patients had webs or had only 1 mm adhesion area.