Background:  We presented of an experience of fiberoptic intubation for a patient with bilateral arytenoid dislocation and fixation. 
Case Report:A 55-year old woman was scheduled for laparoscopic staging operation for endometrial cancer. Preoperative studies and laboratory exams had no notable findings. The anesthesia was induced with propofol 2 mg/kg and rocuronium 0.6 mg/kg, intravenously, and inhalation of 3% sevoflurane was used for maintenance.  Intubation was attempted with direct laryngoscopy. Cormack-Lahene laryngoscopy grade was 2, however, glottic opening was small. 6.0 mm endotracheal tube was inserted while counterclockwise rotating, but it was only advanced at 18 cm depth of insertion. We cancelled the operation. Consultation was requested to otolaryngologist. She had undergone neck CT, indirect laryngoscopy and laryngeal electromyogram.
Conclusively, she was diagnosed with both arytenoid dislocation and fixation. After a few days, awake fiberoptic guided intubation was planned.  A 4.2-mm fiberoptic bronchoscope was inserted through the left nostril and it was advanced into the nasopharynx and further down till the epiglottis and vocal cords were visualized. Similar to laryngoscopic finding, arytenoid cartilages were dysmorphic and fixed, and normal free movement of arytenoids was not shown. Two vocal cords were only partially abducted. We encouraged the patient to make an high pitched phonation. Fiberoptic bronchoscopy was gently passed through vocal cord, and 6.0-mm endotracheal tube was inserted over the bronchoscopy successfully. 6 hours of operation was uneventful.  
Discussion: Arytenoid abnormality is rarely associated with difficult intubation in previous reports, however, bilateral fixed morphology of the structures may hinder inserting appropriate size of endotracheal tube under general anesthesia. Careful history taking and physical examination as well as preoperative laryngoscopy and imaging study are helpful for planning of anesthesia of patients.
References: 1.     New insights into the pathomechanism of postintubation arytenoid subluxation. Anesthesiology. 1999 ;91:659-66. Paulsen FP, Rudert HH, Tillmann BN.
Learning points: Bilateral arytenoid dislocation and fixation is rare disease but challenging for intubation. It may impinge the tracheal tube advancing during general anesthesia or awake intubation. Selection of appropriate size of endotracheal tube, fiberscope size, intubation route and cooperation of patient are important factors for successful intubation.

Bilateral arytenoid dislocation and fixation - a rare cause of difficult intubation