Delayed Facial Paralysis following Uneventful KTP Laser Stapedotomy: Two Case Reports and a Review of the Literature

Abstract

Facial palsy that occurs immediately after middle ear surgery (stapedectomy, stapedotomy, and tympanoplasty) can be a consequence of the local anesthetics and it regresses completely within a few hours. In the case of delayed facial palsy, the alarming symptom occurs several days or even weeks after uneventful surgery. The mechanism of the neural dysfunction is not readily defined. Surgical stress, intraoperative trauma, or laceration of the chorda tympani nerve with a resultant retrograde facial nerve edema can all be provoking etiological factors. A dehiscent bony facial canal or a multiple microporotic fallopian canal (microtrauma or laser effect) can also contribute to the development of this rare phenomenon. The most popular theory related to the explanation of delayed facial palsy at present is the reactivation of dormant viruses. Both the thermal effect of the laser and the elevation of the tympanomeatal flap can reactivate viruses resting inside the ganglion geniculi, facial nerve, or facial nuclei. The authors report the case histories of a 55-year-old female, and a 45-year-old male who presented with a delayed facial palsy following laser stapedotomy. The clinical characteristics, the therapeutic options, and the possibility of prevention are discussed.