Various methods have been reported to prevent cicatricial closure of the ostium, including osteotomies of sufficient size [3], uncinectomy [10], suturing of the lacrimal sac to the nasal mucosa [11], use of adjunctive MMC [5], silicone tube intubation [12, 13], use of synthetic polyurethane foam as nasal packing [9, 14], lacrimal irrigation during the follow-up period [15], and use of agents, such as sodium hyaluronate, to reduce postoperative granuloma formation [16]. Among these methods, the adjunctive use of MMC is a popular choice and an accepted modality to prevent cicatrix formation at the osteotomy site during wound healing [17].
Various adjunctive methods of MMC application have been reported, including intraoperative application, topical postoperative eye drops, circumostial injections, or multiple postoperative applications with intraoperative use [18, 19]. However, topical postoperative eye drop use may pose a risk of corneal epithelial erosion if it persists for over 3 days. Additionally, circumostial MMC injections directly into the nasal mucosa should be studied at the cellular level in the future. For reducing postoperative granuloma formation, intraoperative application of MMC to the osteotomy site to cover the entire margin of the ostium site may be considered rather than topical MMC.
TA acetonide is a synthetic corticosteroid that is known to suppress fibrosis and inflammatory responses throughout the early wound-healing process to theoretically reduce scar formation [20]. Kang et al. [16] recently reported the efficacy of TA-impregnated nasal packing in endoscopic DCR combined with postoperative 0.03% MMC eye drops, with overall success rates and granulation occurrence of 96.0% and 10.0%, respectively. However, they did not compare the clinical outcomes between the single use of adjunctive MMC and TA-impregnated nasal packing.
In our study, we used the intraoperative application of adjunctive MMC at a 0.04% concentration for 5 min. We hypothesized that intraoperative MMC application would allow a more adequate application to the entire margin of the ostium site than postoperative MMC with topical eye drops. The combined use of intraoperative MMC and TA-impregnated nasal packing in endoscopic DCR resulted in a surgical success rate of 98.7% and a granuloma incidence rate of 5%. All clinical results were better than those reported in a previous study. However, there was no significant difference in either the success rate or the incidence of granulomas between the single use of adjuvant MMC and TA-impregnated nasal packing. Furthermore, the success rates with granulation were significantly lower than those without. However, granulation did not affect the absolute condition of surgical failure. Granulation occurred in some patients with surgical success, whereas it did not occur in some patients with surgical failure (Table 3). In endoscopic sinus surgery, steroid-impregnated biodegradable nasal dressings have shown positive effects on wound healing [21] by reducing scarring, edema, crusting, and synechiae after surgery [22, 23]. The intranasal application of TA-impregnated absorbable nasal packing, which gradually dissolves in 2 to 3 weeks, would allow the sustained release of corticosteroids, resulting in less scarring and granuloma formation in the nasal ostial opening.
Our study had several limitations. First, we did not assess the size, position, and period of occurrence of ostium granulomas after DCR. We only evaluated the presence or absence of granuloma formation, and did not investigate the degree of granuloma formation or the time of occurrence. Second, the positive effects of absorbable packing materials on granuloma tissue formation were not considered. Nasopores help to enhance rapid reepithelialization and prevent excessive secondary scarring and fibrosis [14], and are believed to accelerate wound healing by providing a wet dressing environment, which helps decrease granuloma formation. Third, steroid eye drops may also affect the surgical outcomes of DCR. We did not exclude the steroid action on the wound-healing process during topical application.
In conclusion, the differences in success rates and granuloma development between the single use of adjuvant MMC and steroid-impregnated nasal packing were not significant. However, the combined use of intraoperative MMC and steroid-impregnated absorbable nasal packing was effective in preventing granulomas and enhancing the surgical success rate. Further studies are needed to investigate the consistency and duration of steroid delivery. More research needs to be done to compare surgical outcomes between nonabsorbable and absorbable nasal packing materials.