Analysis of postoperative effects of different semicircular canal surgical technique in patients with labyrinthine fistulas

Abstract

Objective: Different semicircular canal surgery techniques have been used to treat patients with labyrinthine fistulas caused by middle ear cholesteatoma. This study evaluated postoperative hearing and vestibular function after various semicircular canal surgeries.

Materials and methods: In group 1, from January 2008 to December 2014, 29 patients with middle ear cholesteatoma complicated by labyrinthine fistulas were treated with surgery involving covering the fistulas with simple fascia. In group 2, from January 2015 to October 2021, 36 patients with middle ear cholesteatoma complicated by labyrinthine fistulas were included. Cholesteatomas on the surface of type I labyrinthine fistulas were cleaned using the "under water technique" and capped with a "sandwich" composed of fascia, bone meal, and fascia. Cholesteatomas on the surface of type II and III fistulas were cleaned using the "under water technique," and the labyrinthine fistula was plugged with a "pie" composed of fascia, bone meal, and fascia, and then covered with bone wax.

Results: Some patients with labyrinthine fistulas in group 1 exhibited symptoms of vertigo after surgery. In group 2 Patients with type II labyrinthine fistulas experienced short-term vertigo after semicircular canal occlusion, but no cases of vertigo were reported during long-term follow-up. "sandwich." In patients with type II labyrinthine fistulas, the semicircular canal occlusion influenced postoperative hearing improvement. However, postoperative patient hearing was still superior to preoperative hearing.

Conclusion: The surface of type I labyrinthine fistulas should be capped by a "sandwich" composed of fascia, bone meal, and fascia. Type II and III labyrinthine fistulas should be plugged with a "pie" composed of fascia, bone meal, and fascia, covered with bone wax.

Keywords: analysis; hearing; labyrinthine fistula; middle ear cholesteatoma; semicircular canal occlusion.

FIGURE 1

(A,B) Shows the preoperative and postoperative pattern diagram of a patient with type I labyrinteric fistula. The red arrows (a–f) respectively, represent the bony labyrinth, endosteum, perilymphatic space, membranous labyrinth, bone meal, fascia. Pictures (C–F) are intraoperative of a patient with type I labyrinthine fistula. (C): Type I labyrinthine fistula with endosteum and cholesteatoma epithelium covered with surface (the black arrow). (D): Fascia placed on the surface of the fistula (the black arrow). (E): Surface of the fascia with clean bone meal (the black arrow). (F): Fascia placed on the surface of the bone meal (the black arrow).

FIGURE 2

(A,B) Shows the preoperative and postoperative pattern diagram of a patient with type II labyrinteric fistula. The red arrows (a–f) respectively, represent the bony labyrinth, endosteum, perilymphatic space, membranous labyrinth, bone meal, fascia. Pictures (C–F) are intraoperative of a patient with type II labyrinthine fistula. (C): Labyrinthine type II fistula with superficial cholesteatoma epithelium showing deep invagination within the external semicircular canals (the black arrow). (D): Destruction of the endosteum is visible after “under water” cleaning of the cholesteatoma epithelium on the surface of the fistula (the black arrow). (E): Placement of clean bone meal inside the fascia with a “pie” filling of the external semicircular canal (the black arrow). (F): Filling the posterior surface of the semicircular canal by application of fascia is observed (the black arrow).

FIGURE 3

Pictures (A–E) are intraoperative of a patient with type III labyrinthine fistula. (A): Type III labyrinth fistula with the superficial cholesteatoma epithelium located deep in the external semicircular canal (the black arrow). (B): Cholesteatoma epithelium on the surface of the fistula (the black arrow). After the cholesteatoma epithelium is cleaned “under water,” the membrane labyrinth is destroyed. (C): The fascia is placed on the surface of the fistula (the black arrow). (D): Clean bone powder is placed on the fascia and the external semicircular canal is filled with a “pie” shape (the black arrow). (E): The surface of the semicircular canal is covered with bone wax (the black arrow). (F,G) Show the preoperative and postoperative pattern diagram of a patient with type III labyrinteric fistula. The red arrows (a–f) respectively, represent the bony labyrinth, endosteum, perilymphatic space, membranous labyrinth, bone meal, fascia.

FIGURE 4

Caloric test results [summed maximum slow phase velocity of the eye, caloric sMSPV (°/s)] of the operated side of 8 patients with vertigo in group 2 before and after surgical plugging of external semicircular canal. Each patient is color coded. Vestibular function examinations performed at 1 week and 3 months postoperatively revealed that the affected side was weakened in all eight patients. The vestibular function of the patient was the worst one week after the operation, and gradually recovered in the later period, but it was not normal.

FIGURE 5

Computed tomography (CT) images acquired (A,B) preoperatively from a patient with type I labyrinthine fistula. Preoperative (A,B): The right cholesteatoma is adjacent to bone resorption, the boundary with the external semicircular canal is unclear, and the shape of the external semicircular canal is acceptable (the red arrows). Postoperative (C,D): The cholesteatoma has been removed, the shape of the lateral semicircular canal is acceptable, and intraoperative fillers are applied to fill the external semicircular canal (the red arrows).

FIGURE 6

CT images acquired before and after surgery from a patient with type II labyrinthine fistula undergoing a second surgery. Preoperative (A,B): The left cholesteatoma is adjacent to the bone resorption with a normal external semicircular canal shape (the red arrows). Postoperative (C,D): The removal of cholesteatoma, the abnormal shape of the external semicircular canal, and the intraoperative fillers inside and adjacent to it (the red arrows).

FIGURE 7

Pre- and postoperative CT images acquired from a patient with a type III labyrinthine fistula. Preoperative (A,B): The left cholesteatoma is adjacent to the bone destruction (the red arrows). Postoperative (C,D): The removal of the cholesteatoma, the abnormal shape of the external semicircular canal, and intraoperative fillers inside and adjacent to it (the red arrows).