Acute onset of peripheral facial nerve palsy necessitates a prompt evaluation and treatment by otorhinolaryngologists. Generally, most patients are of the opinion that treatment of facial palsy is in the domain of otolaryngology. Although several reports on cases of peripheral facial nerve palsy are available, few reports on cases of central facial nerve palsy exist. In this study, we elucidated the etiological background of patients with types of facial nerve palsy, such as peripheral and central facial nerve palsy, at Aizawa Hospital, a regional core hospital in Japan. We conducted a retrospective chart review of 374 patients with peripheral and central facial nerve palsies who visited our hospital from January 2016 to December 2020. Out of the 374 patients, 258 (69%), 108 (29%), and eight (2%) patients had peripheral, central, and unknown facial nerve palsies, respectively. The most prevalent causes of peripheral and central facial nerve palsies were Bell's palsy (211 out of 258 patients, 81%) and cerebral infarction (72 out of 108 patients, 67%), respectively. On the one hand, patients who visited the emergency department for initial medical care accounted for 40% of patients with peripheral facial nerve palsy and 73% of patients with central facial nerve palsy. On the other hand, only 16% of patients with peripheral facial nerve palsy visited the otolaryngology department. Patients with facial palsy, irrespective of the type, visited the emergency department more frequently than the otorhinolaryngology department. For an appropriate workup and treatment of patients with peripheral facial nerve palsy at the otorhinolaryngology department, co-operation with other medical departments is necessary.

　 In recent years, artificial intelligence (AI) technologies, such as image recognition and natural language processing, have been increasingly used in the medical field, and its range of application is expanding with technological innovation. However, some limitations to its capabilities in some fields have been acknowledged. Therefore, our understanding of its use and associated risks is necessary for safe and effective medical applications. ChatGPT is one of the natural language processing technologies that were released in 2022. AI, which uses data from the Internet and other sentences, generates responses to input instructions (prompts) and can further increase its accuracy depending on the instruction method. Few studies have reported on the effectiveness of Japanese, a non-English language, in the medical field, as it has been reported to attain the passing scores of bar examinations and medical licensing examinations in the United States. In this study, we evaluated the performance of ChatGPT in the 2022 Otolaryngology Specialist Examination and discussed its effectiveness in the field of Japanese language otolaryngology and the challenges of using AI.

　 In this study, 48 questions from the 2022 Otolaryngology Specialist Examination, including multiple choice questions but excluding those with diagrams, were used in this evaluation. In inputting the question statements as prompts, we used four different methods: original questions, Japanese prompts, English translations of the Japanese prompts, and English prompts. Since two different versions of ChatGPT-GPT-3.5 and GPT-4-are currently available, eight different methods were validated at five different times. The accuracy of their responses were compared to the correct answers and evaluated.

　For ChatGPT-3.5 and GPT-4, the average accuracies were 31.67% and 45.42%, when the question statements were used as prompts. The accuracies when Japanese prompts were used were 35.00% and 43.75% for ChatGPT-3.5 and GPT-4, respectively. For the translated English instructions, the accuracies were 39.58% and 52.08% for ChatGPT-3.5 and GPT-4, respectively. For the direct English prompts, the accuracies were 50.42% and 65.00% for ChatGPT-3.5 and GPT-4, respectively. The percentage of correct answers improved with the GPT version and English translations. A similar trend was observed, with respect to the types of questions answered correctly by GPT-3.5 and GPT-4. With respect to questions with low percentages of correct answers, we observed similarities. The questions with the highest percentage of incorrect answers tended to be related to otology, vertigo equilibrium, voice, and institutions.

　ChatGPT had a maximum correct response rate of 65% in the Otolaryngology Specialist Examination. In the future, higher correct response rates may be achieved by improving the accuracy of ChatGPT and developing new prompts. From our study findings, a non-English language, Japanese, can achieve a certain level of accuracy in the field of otolaryngology, and this finding is necessary in improving our understanding of the usefulness and challenges of AI in clinical otolaryngology. ChatGPT did not always provide correct answers. Additionally, it had correct response rates that varied with the types of prompt. Therefore, at this time, the final judgement must be made by a person on the answers provided by ChatGPT. In the field of otolaryngology, physicians would need to be tactful in the use of artificial intelligence in clinical management practices, such as low-risk medical treatments.

　 Extracranial trigeminal schwannoma, a rare tumor, accounts for about 5% of all trigeminal schwannomas. We report two cases of extracranial trigeminal schwannoma located in the pterygopalatine fossa, which were treated by the endoscopic endonasal trans-maxillary approach. Intracapsular subtotal tumor removal was performed. In one patient, maxillary artery ligation was necessary. The symptoms of cheek paresthesia were relieved in both patients after the surgery. Though surgical indications for trigeminal schwannomas are limited, tumor removal is required in symptomatic or young patients. Symptomatic trigeminal schwannoma located in the pterygopalatine fossa could be removed by the endoscopic trans-maxillary approach.

　 For the initial management of Otitis Media with Effusion (OME) in children using a ventilation tube, the guidelines for OME in children (2022 edition) recommend the use of short-term ventilation tubes. In our hospital, the type D tube is used for managing all cases. In this study, we evaluated the use of type D tubes among 69 patients (122 ears) under the age of 15 years who underwent treatment at our hospital from April 2013 to December 2017. The average age of this cohort was 5.5 years (Range: 1-13 years). We retrospectively reviewed patients' clinical characteristics (age, sex, medical history, characteristics of middle ear fluid, tube insertion time, recurrence rates, perforation rates, and infection rates), preoperative neutrophil-lymphocyte rates (NLR), and platelet-lymphocyte rates (PLR). The average tube extrusion time was 15.9 months. The rates of recurrence, infection, and perforation were 13.1% (16 ears), 7.4% (9 ears), and 6.0% (7 ears), respectively. The group with recurrence had a significantly longer tube extrusion time than the group without recurrence. In comparing patients based on middle ear fluid characteristics and recurrence rate, no differences in NLR and PLR were observed. Based on our findings, the characteristics of type D tubes are essential in choosing a ventilation tube for OME management in children.