[Unexpectedly complicated laryngoscopy caused by a massive mandibular tori].

Here, we report a case of an unexpectedly complicated laryngoscopy caused by massive mandibular tori. A 64-year-old man with mitral regurgitation and aortic regurgitation was scheduled for a double valve replacement. Thyromental distance and the Mallampati score were used as predictive factors of difficult intubation, and both factors were within the normal range. Anesthesia with controlled ventilation was started with fentanyl, propofol and vecuronium. After the attainment of full muscle relaxation, an experienced anesthesiologist performed direct laryngoscopy. It was not possible to intubate the patient under direct laryngoscopy because of massive mandibular tori which had not been detected prior to induction. Following the failure of direct laryngoscopy, a McCoy laryngoscope and a gum elastic bougie were deployed to improve vision. Intubation with a 7.5 mm tube was successful at the third attempt. We hope our experience will serve as a reminder to clinicians that mandibular tori, although benign and without subjective symptoms, could have significant effects upon direct laryngoscopy by compromising the line of vision. Preoperative oral evaluation is critical and aggressive treatment should be considered.