Introduction : We previously studied the mouse inner ear by 7.05 Tesla (T) MRI after the intratympanic administration of gadolinium. The appearance of the endolymphatic space (ES) in the cochlea is similar to the pathological appearance, and cochlear endolymphatic hydrops could thus be detected. However, we had not previously detected the ES in the vestibule. The aim of this study was to visualize the ES in the mouse vestibule using MRI. Materials and methods : The vestibular structures of 56 C57BL/6 mice were visualized using 7.05T MRI at 1-2 hours after the intratympanic injection of gadolinium contrast media. We observed the ES on the modiolar plane. We counted both the pixel counts of the ES and the vestibular space on the plane in which the ES showed its maximum diameter. The ES ratio, which was defined as the pixel count of the ES divided by the pixel count of the vestibular space was measured in each case. Results : The ES was visualized in all ears. The mean ES ratio was 0.419 ± 0.05 and the median ES ratio was 0.420. Conclusion : The living mouse ES could be accurately visualized by MRI. This method could visualize morphological changes in the ES of model animals with endolymphatic hydrops and therefore is considered to be useful for investigating the cause of vertigo attacks in patients with Meniere's disease.

We performed OK-432 (Picibanil^®) injection therapy to treat 2 cases of lymphangioma, and 3 cases of ranula (1 sublingual type, 2 mixed type) in children from January 2015 to December 2018. The therapeutic effect was disease disappearance in 2 cases, disease reduction in 2 cases, and unchanged in 1 case. The cases with disease disappearance were all cystic lymphangioma cases. In our department, the first choice of treatment for cystic lymphangioma is OK-432. For ranulas, first choice of treatment is OK-432 if minimally invasive therapy is desired. However, we perform sublingual gland resection if there is a strong hope of a radical cure in the short term. Regarding the side effects associated with OK-432, postoperative dyspnea may occur if the cystic lesion extends to the posterior pharyngeal wall or parapharyngeal space, and it is therefore necessary to consider the likely patient response before starting this treatment regimen.

We investigated the incidence and risk factors of pharyngocutaneous fistula (PCF) after total laryngectomy. The study subjects were 36 patients who had received total laryngectomy at Miyazaki University Hospital between April 1, 2013, and December 31, 2019. PCF developed in 9 patients (25%). This rate was even higher among patients with diabetes (3/6 ; 50%). However, we should have evaluated the disease severity of diabetes at the degree of the tissue disorder, and not at the blood sugar level. The incidence of PCF in salvage cases was 31.6% (6/19). As a result, we concluded that the operation using the prophylactic flaps for all salvage cases was somewhat excessive. In the future, we will continue to deal with the PCF by early treatment.

Periodic fever, aphthous stomatitis, pharyngitis, and cervical adenitis (PFAPA) syndrome is an autoinflammatory disease. It often occurs in children ranging from 3 to 4 years of age. The episode of fever itself does not affect growth and development, and it often demonstrates spontaneous remission. Tonsillectomy and medication are the alternatives to treat the symptoms. Tonsillectomy leads to a high rate of complete remission, while corticosteroids promptly stop disease episodes and a H₂ blocker, cimetidine can postpone febrile episodes. Of the 7 cases we experienced in our department, 5 cases underwent tonsillectomy, and all cases achieved remission. Medication was also efficient, with fever resolution and extension of the interval between fever episodes. PFAPA syndrome may be diagnosed and treated as chronic tonsillitis, since some of the symptoms are common, but this syndrome should be included in the differential diagnosis in order to expand the treatment options and contribute to improving the QOL of patients and their families.

HIV (human immunodeficiency virus) lowers the immune capacity of the host and causes AIDS (acquired immunodeficiency syndrome) when it progresses. HIV infection is known to have a variety of symptoms, and it is often diagnosed based on the occurrence of various otorhinolaryngological conditions. We experienced a case in which an HIV infection was diagnosed based on delayed wound healing after tonsillectomy. The early initiation of treatment for HIV infection is known to be effective for controlling progression, so it is important to detect HIV infection as early as possible. Preoperative HIV screening tests may lead to the early detection of HIV, and such tests are also important to prevent delayed wound healing. In Japan, it remains a problem that preoperative HIV screening is sometimes not allowed under by the Japanese National health insurance system.

Provox^® is used as a substitute voice after laryngectomy, but we may sometimes need to remove this device. This time, we report that we had difficulty in closing a tracheoesophageal fistula after removing a Provox^®. The patient was a 78-year-old man. After removing the Provox^®, we could not close the tracheoesophageal fistula by repeated simple suturing. We finally succeeded in closing the fistula by interpositioning the previously transferred pectoral major muscle flap between the esophagus and the trachea. The closure of the fistula after Provox^® removal may require a procedure to separate the trachea from the esophagus and then to interposition well vascularized tissue. This case suggests that there is a high possibility of encountering difficulty in closing such a fistula, especially in cases who have undergone radiation therapy. As a result the decision to select Provox^® placement should be made very carefully and after such placement it should only be removed when it is absolutely necessary.

Bezold abscess is a rare complication of acute otitis media with mastoiditis presenting as a laterocervical abscess. Acute mastoiditis may develop anatomically in six directions and may cause complications. As one such complication, a Bezold abscess occurs due to the inferior medial and mastoid directions. We herein report a 43-year-old man who progressed from otitis media to Bezold abscess with a history of schizophrenia and poor overall understanding of his disease. He was referred to our hospital with left head pain and swelling. Computed tomography revealed mastoiditis with neck abscesses. The patient received a post- auricular incision for drainage of the neck abscess under local anesthesia ; mastoidectomy was not performed. After the operation, intravenous antibiotics and saline irrigation for the wound were continued, and the inflammation was relieved. The patient was discharged 12 days after surgery.