Primary ciliary dyskinesia (PCD) is a hereditary disorder caused by biallelic mutations of genes related to the cilia. The estimated prevalence of PCD is 1 in 20,000 live births. In cases without situs inversus, the diagnosis can be very difficult. In Japan, PCD without situs inversus is underdiagnosed at present. In many cases reported in Japan, the diagnosis of PCD is based only on detection of inner dynein arm defect by electron microscopy. Since the inner dynein arms may not be visualized even in normal subjects, diagnosis based on this finding alone needs further validation. Since PCD is a hereditary disease, a diagnosis of this condition would not only have an impact on the patients themselves, but also on his/her family members. Thus, caution should be exercised in making the diagnosis of PCD. Otorhinolaryngologists inspect nasal cavities and eardrums in daily practice, and can perform the biopsies necessary for the diagnosis by electron microscopy. For making a definitive diagnosis of PCD, nasal nitric oxide concentration measurement, electron-microscopic study of the cilia, and genetic tests are required. Taking all these aspects into consideration, I firmly believe that a correct diagnosis of PCD is of great importance. Therefore, basic knowledge about cilia and three kinds of diagnostic criteria are explained. Tips for obtaining biopsy specimens for electron microscopy are shown. Since there is a known correlation between genetic changes and ciliary ultrastructure, it is desirable that both tests be performed and that the test results are compatible. At present, no specific therapies are available for PCD. In the near future, treatment based on genetic mutational changes may be developed as personalized medicine. Making a genetic diagnosis is important for each patient to receive such treatment.

Several studies until the early 2000’s reported the occurrence of hearing loss and other auditory deficits as a result of deployment of airbags in vehicles. Although the number of publications on acoustic trauma caused by airbag deployment appears to have decreased recently, patients with acoustic trauma caused by airbag inflation are still encountered, and early intensive treatment after acoustic trauma is thought to be essential for recovery from hearing loss. Herein, we present a case of acoustic trauma of the right ear caused by side-airbag inflation.

A 32-year-old male was driving at the speed of about 40 km/h, when he was hit by a car from the right rear; the collision caused the airbag on the right side to deploy with a crashing sound. The subject developed persistent tinnitus and hearing loss in the right ear, and presented to our clinic. He had no history of vertigo or dizziness at the first referral. Otoscopic examination revealed no signs of bleeding or perforation of the tympanic membrane. Pure-tone audiometry revealed sensorineural hearing loss affecting high frequencies in the right ear. Computed tomography of the temporal bone revealed no abnormal findings. The patient was started on treatment with prednisolone and vitamin B12. Repeat pure-tone audiometry after nine days of medication revealed improvement of the hearing loss in intermediate frequencies, but no improvement in the tinnitus in the right ear. Subsequent treatment 8 sessions of hyperbaric oxygen therapy also failed to improve the hearing loss in high frequencies or tinnitus.

In summary, permanent hearing loss or tinnitus can sometimes occur as a result of airbag deployment. It is important to be aware of the possibility of inner ear damage as one of the complications of air bag deployment.

Nasopalatine duct cyst is one of the nonodontogenic epithelial cysts that arises from the epithelial remnants of the nasopalatine duct of the fetus. We present the case of a 76-year-old male patient who presented to us with a large nasopalatine duct cyst in the middle portion of the hard plate. Elevation of the floor of the right nasal cavity and a bone defect of the hard plate were observed. The patient complained of palatal swelling and nasal obstruction. We performed transnasal endoscopic surgery and performed mucosal resection, to the extent possible, in the floor of the nasal cavity over the cyst roof. The palatal swelling and nasal obstruction resolved after the surgery, and the patient had an uneventful clinical course.

A review of the operative methods for treating nasopalatine cysts showed the importance of multiple directional drainage, especially in the presence of a bone defect, and for that purpose, transnasal drainage is useful.

Sialodochitis fibrinosa is a rare disorder characterized by repetitive swelling of the salivary gland resulting from obstructive changes of the salivary duct caused by the presence of fibrinous plugs. We report two cases of sialodochitis fibrinosa in which CT revealed a calcified shadow in the salivary gland. Both cases presented with recurrent swelling of the salivary gland and were initially diagnosed, based on the CT findings, as having sialolithiasis. However, after a long duration of follow-up, fibrinous plugs were detected in the salivary duct, with eosinophilic infiltration. Based on the above findings, we made the definitive diagnosis of sialodochitis fibrinosa. The patients’ symptoms were successfully controlled by the administration of antiallergic drugs. We should bear in mind the possibility of sialodochitis fibrinosa during the management of sialolithiasis, especially in cases without salivary colic.

Kawasaki disease, also known as acute febrile mucocutaneous lymph node syndrome, is a systemic vasculitis of unknown etiology. We report a rare case of incomplete Kawasaki disease in a 24-month-old male infant presenting with swelling of the right neck. CT showed ring enhancement in the retropharyngeal space. Based on the findings, we made the clinical diagnosis of retropharyngeal abscess. Puncture drainage via the oral approach was performed with ultrasonographic guidance under general anesthesia. The symptom was relieved immediately and the patient was discharged six days after the operation.

It is necessary to consider the possibility of incomplete Kawasaki disease in a patient presenting with neck swelling suggestive of a retropharyngeal abscess.

Submucosal pharyngeal foreign bodies are generally surgically removed. Herein, we report the case of a patient with a buried fish bone in the hypopharynx that was successfully removed by transoral videolaryngoscopic surgery (TOVS). A 68-year-old woman presented with odynophagia after swallowing a fish bone on the day before admission. The bone could not be identified on endoscopic examination. Subsequent computed tomography (CT) revealed a 26-mm linear foreign body deeply embedded in the wall of hypopharynx. TOVS was performed under general anesthesia, which provided excellent visibility and easy access to the hypopharynx. The mucosal incision was executed with a unipolar coagulation knife. The buried fish bone was detected in the submucosal layer of hypopharynx and removed with forceps. The incised mucosa was left open, but with no bleeding or infection. The TOVS approach was used for removal of a pharyngeal foreign body without a cervical incision. This technique of transoral surgery could potentially be utilized for a variety of cases.

Ectopic thyroid refers to the presence of thyroid tissue in locations other than the normal anterior neck location. Herein, we report 2 cases of ectopic lingual thyroid in two 73-year-old and 61-year-old women who presented with a mass at the base of the tongue. Neither patients had any thyroid tissue in the normal anterior neck location. Scintigraphy showed ^99mTc accumulation only at the base of tongue in both cases. In one of the two patients, we performed fine needle aspiration cytology (FNAC) from the mass at the lingual base and confirmed the presence of follicular epithelial cells. In addition, a high level of thyroglobulin was identified in the FNAC specimen. Immunostaining of the cell block of the FNAC specimens showed positive staining for both TTF1 and TPO. The current cases suggest the usefulness of FNAC-based cell block staining for a precise diagnosis of the ectopic lingual thyroid.

It is the most frequent form of thyroid dysgenesis, accounting for 48%–61% of all the cases. Lingual thyroid is the most common type accounting for 90% of the cases, while the sublingual types are less frequently encountered.

It has been suggested that FNAC, and measurement of the thyroglobulin level in FNAC specimens are very useful for definitive diagnosis of ectopic thyroid.

In many cases, synchronous parotid gland tumors are multiple occurrences of Warthin’s tumors, and occurrence of histologically different tumors in the same parotid gland is rare. We report a case of synchronous occurrence of a pleomorphic adenoma and myoepithelioma in the same parotid gland.

A 74-year-old man presented with two masses in the left parotid gland. On magnetic resonance imaging, the inferior tumor was visualized on T2-weighted images as a mixture of high signal intensity and low signal intensity; on the other hand, the superior tumor showed high signal intensity in the peripheral region and uniform low signal intensity in the central region. Therefore we considered the two tumors as being of different histological types. The tumors were resected by superficial parotidectomy. The histopathological diagnosis of the inferior tumor was pleomorphic adenoma, while that of the superior tumor was myoepithelioma. Until now, two years since the surgery, there has been no recurrence of either type of tumor in the parotid gland.

In patients with multiple parotid gland tumors, diagnosis of the tissue types of the tumors prior to the operation is important, because it has an influence on the prognosis of the patients.

Kimura disease (soft eosinophilic granulomatosis) is a chronic inflammatory granulomatous condition characterized by eosinophilic infiltration of the soft tissues. We treated a 40-year-old male patient with steroid-resistant Kimura disease on the left side of the neck by radiotherapy. The patient presented with a mass in the left side of the neck that he had first noticed 5 years earlier. He had received steroid therapy, but developed recurrent disease and was judged as being resistant to steroid therapy. The lesion was irradiated with 30 Gy, in five-weekly fractions of 2 Gy. After radiotherapy, complete remission of the lesion was observed, with improvements in both the peripheral blood eosinophil count and the serum IgE level. Neither lesion recurrence, nor delayed complications were detected up to 5 years after the radiotherapy. This case indicates that radiotherapy is an effective treatment option for Kimura disease. However, careful follow-up and informed consent for the treatment are necessary.