Hearing Preserved Four Cases of Iatrogenic Labyrinthine Fistula Treatment

Suh, Seock Bum; Lee, Kwang Sun

Abstract

Evaluation of postoperative hearing acuity and equilibrium was performed in four patients with labyrinthine fistula caused by iatrogenic procedure. Surgical trauma inflicted upon the membranous labyrinth is an uncommon, but often catastrophic, complication of chronic ear surgery. The most vulnerable areas are the oval window and the lateral semicircular canal. Methods of injury include subluxation of the foot plate, fracture of the lateral canal by drill or chisel, and accidental opening of the labyrinth. Three cases of fistula of the lateral and posterior canal during ear surgery are presented. All of three occured while drilling. The other one occured due to iatrogenic stapedectomy. The interrupted semicircular canals were obliterated firmly with autologous materials such as fascia, perichondrium, bone chips, and cartilage. These cases were documented by pre and post operative audiograms, vestibular function tests. One interesting finding was that none of these cases were compromised cochlear function. The dictum that an accidentally opened labyrinth will automatically result in a dead ear is shown to be not necessarily true. These cases indicates that manipulation of the semicircular canal with awareness can be conducted without damaging the cochlear function, and that the treatment of labyrinthine fistulas shoud be performed very carefully but not so conservatively as to lead to future problems.