Abstract: Objective To investigate the predictive effect of the laryngoscopy scoring system on cases of difficult glottic exposure during laryngoscopy. Methods This was a double-blind study, in which the laryngoscopy scoring system was used to preoperatively examine and score patients who were undergoing laryngoscopy. The surgeon assessed and graded the difficulty in glottis exposure during the operation, to assess whether it was relevant and could analyze the associated factors. Results When the patient had a preoperative laryngoscope score of ≤6, an acceptable laryngeal exposure was observed at an 82.8% probability, while a difficult laryngeal exposure was found at 17.2%. When the patient's preoperative laryngoscopy score exceeded 6, a 100% probability of surgery would lead to difficult laryngeal exposure. The sensitivity, specificity, misdiagnosis, and missed-diagnosis rates of the difficult laryngeal exposure prediction system(>6 points)were 100%(20/20), 82.8%(48/58), 0%(0/20), and 17.2%(10/58), respectively. Statistically significant variables included open cleavage distance, thyroid cartilage angle-underarm distance, neck extension angle, body mass index, and small jaw deformity. Conclusion Using the simple and feasible preoperative support laryngoscopy scoring system, a threshold of 6 points was used to distinguish cases with difficult laryngeal exposure from those with acceptable laryngeal exposure, with relatively high accuracy. Furthermore, this scoring system proved to be simple and easy to operate in clinical practice and could be certainly considered practicable.

Key words: Laryngoscopy, Sugery, Exposure