Fallopian canal dehiscence at pediatric cholesteatoma surgery.

The objectives of the study were to investigate the characteristics of ears with dehiscence of the fallopian canal at the time of cholesteatoma surgery and the relationship between dehiscence and age, and to consider the reasons why the fallopian canal tends to be preserved in pediatric patients. This study included 37 ears with cholesteatoma in pediatric patients (mean age 9.2 years, age range 4-14 years) and 273 ears with cholesteatoma in non-pediatric patients (mean age 45 years, age range 15-84 years). Patients were treated between January 2006 and April 2012. All patients had undergone prior tympanoplasty under general anesthesia at our institution. Facial canal dehiscence was evaluated by inspection and through palpation by blunt picking after the pathological tissues had been removed. The size of fallopian canal dehiscence was not investigated in this study. The frequency of dehiscence of the fallopian canal according to the type of cholesteatoma and coexisting pathological conditions, including destruction of the stapes, presence of a labyrinthine fistula, and dural exposure, were compared between the pediatric and non-pediatric groups. The frequency of dehiscence in cases with destruction of the stapes was also compared between the pediatric and non-pediatric groups. Dehiscence of the fallopian canal occurred in 6 of 37 ears (16.8 %) in the pediatric group and 91 of 273 ears (33.3 %) in the non-pediatric group (p < 0.05). In congenital cholesteatoma, the frequency of dehiscence was lower in the pediatric group than in the non-pediatric group (p < 0.05). However, in other types of cholesteatoma there was no statistically difference between the two types of cholesteatoma. The frequency of the destruction of the stapes was higher in the pediatric group than in the non-pediatric group (43.2 vs. 16.5 %, p < 0.001). In patients with severe destruction of the stapes, the fallopian canal was preserved more frequently in the pediatric group than in the non-pediatric group (p < 0.05). The frequency of dehiscence of the fallopian canal at the time of cholesteatoma surgery was lower in the ears of pediatric patients than in the ears of non-pediatric patients. This is probably due to the difference in types of cholesteatoma between the two groups and other unknown mechanisms.