A precise knowledge of the local three-dimensional anatomy is necessary for temporal bone surgeons, because of the narrow surgical field available to them under the microscope or endoscope and the need to avoid irreversible damage to critical structures. In addition, temporal bone surgery has until now been considered challenging because it has been mainly learnt directly in the operating room through On the Job training (OJT). Recently, however, there have been greater opportunities for OFF the job training (OFF-JT), in that training and simulation for temporal bone surgery has become possible using cadavers, virtual reality, and 3D models. Each OFF-JT has its own advantages and disadvantages, but the 3D temporal bone model has the advantages of being free from ethical issues, of high anatomical reproducibility, and of allowing training using the same instruments as in actual surgery. The 3D temporal bone model is effective for surgical training and is also useful for preoperative and intraoperative simulation. By allowing the problems of cost and manufacturing complexity to be overcome, the 3D model is expected to be more widely used and to contribute to safe and reliable temporal bone surgery.

Background: Patients with idiopathic sudden sensorineural hearing loss (ISSNHL) in Japan are generally initiated on steroid therapy as soon as possible following the onset of hearing loss. On the other hand, there are several reports to suggest that some patients with ISSNHL are cured even without oral or intravenous steroid therapy.

Subjects and Methods: In the current study, data of five patients with ISSNHL who did not receive steroid therapy, batroxobin, or prostaglandin E1, and of 169 patients with ISSNHL who had received these treatments were retrospectively analyzed. The severity and type of hearing loss, hearing level change, and past clinical history were evaluated. The inclusion criteria of the cases, severity of hearing loss, and hearing improvement were evaluated using the criteria defined by the Research Committee of the Ministry of Health and Welfare for Acute Profound Deafness of Japan.

Results: The five patients with ISSNHL who did not receive steroid therapy included three Grade 2 cases, and two Grade 3 cases. The cure rate in these five cases was 40.0%, and those in the Grade 2 and Grade 3 cases were 33.3%, and 50.0%, respectively.

Conclusions: Some cases of ISSNHL appeared to be cured even without steroid therapy.

Japan is a rapidly aging society, and one area of concern is hearing loss among the elderly. Hearing loss is often treated by cochlear implantation in the non-elderly population, and while the number of cochlear implant surgeries for the elderly with hearing loss has been increasing, relatively few reports are available on the effectiveness of cochlear implantation for this group. We thus collected the data of elderly patients who underwent cochlear implantation at our department between 2016 and 2020. The total of 20 patients were divided into two groups: the early elderly group (65 to 74 years) of 10 patients (10 ears) and the late elderly group (75 years or older) of 10 patients (10 ears).

We collected data on the patient background, the speech discrimination ability based on objective preoperative and one-year-postoperative measurement of word sound listening performance using the 67-S word chart and comparison of the CI-2004 word sound listening performance (monosyllables, words, and sentences), a subjective postoperative hearing questionnaire and a subjective satisfaction questionnaire based on the Nijmegen Cochlear Implant Questionnaire (NCIQ) Both patients and family members were asked to fill out the NCIQ for all the patients.

The results of the 67-S word chart assessment showed postoperative improvement within each group while assessment by the CI-2004 showed a similar degree of improvement in the two groups; and the subjective postoperative hearing questionnaire showed that both groups adequately used their cochlear implants. The results of the NCIQ assessment showed that patients in the early group felt there was significant improvement in the postoperative period, while those in the late group did not. However, the NCIQ responses of the family members suggested significant improvement in the postoperative period in both groups.

Our study results suggest that cochlear implantation may yield improvements even in elderly patients with hearing loss.

We encountered a case of cholesterol granuloma caused by an iron fragment trapped at the tympanic orifice of the eustachian tube. The patient was an 80-year-old man who presented with a 4-year history of recurrent bloody otorrhea on the left side. While he was engaged in iron welding 25 years ago, a molten iron fragment had accidentally entered his left ear. Two weeks after the welding accident, the patient had undergone tympanoplasty at another hospital, and postoperative audiometry had revealed total deafness in the left ear.

High-resolution temporal bone CT revealed a high-density material measuring 4 mm in diameter that appeared to be a metal piece at the tympanic orifice of the eustachian tube. Tympanoplasty was performed for the purpose of removing the foreign body. Granulation tissue around the mastoid antrum, superior tympanic cavity, and ossicles was removed, and then the foreign body trapped in the tympanic orifice of the eustachian tube was separated and removed. Histopathological examination of the granulation tissue in the mastoid antrum revealed a cholesterol granuloma. The otorrhea resolved postoperatively, and 6 months after the surgery, CT no longer revealed any diffuse soft tissue opacity in the middle ear cavity. Cholesterol granuloma in this case was presumably caused by long-term obstruction of the eustachian tube by the foreign body.

A 77-year-old man presented to our hospital with bilateral hearing loss and bilateral ear canal stenosis. We considered that his ear canals had gradually narrowed due to medial meatal fibrosis caused by chronic otitis media, since he had a history of habitual ear scratching in both ears. Computed tomography revealed external auditory canal stenosis on both sides. The tympanic cavity was filled with soft tissue, with destruction of the ossicles, in the left ear. On the basis of these findings, we assumed that the destruction of the ossicles in the left ear was caused by external auditory canal cholesteatoma developing as a result of the stenosis. Exploratory tympanotomy showed that the left middle ear was filled with a cholesteatoma, with erosion of the ossicles. The cholesteatoma was located inside the tympanic membrane without any connection, suggesting that it was congenital. Thus, in this patient, the congenital cholesteatoma had remained undetected until the age of 77. That is because the tympanic membrane could not be observed due to stenosis of the external auditory canal, and even his hearing loss had been diagnosed as mixed hearing loss due to both aging and the stenosis of the external auditory canal, without examination by computed tomography. In patients where it is difficult to observe the tympanic membrane because of ear canal stenosis, it is important to perform imaging to check for internal lesions.

Nasopharyngeal angiofibroma (NA) is a benign mesenchymal tumor that usually occurs in adolescent males, and rarely affects middle-aged patients. We report a case of NA in a middle-aged man with a mental disorder who presented with airway obstruction that required emergency tracheostomy. Our patient had difficulty in communicating his complaints because he had suffered from schizophrenia from his adolescent years, so that the tumor had remained unrecognized until it had grown to a huge size. Endoscopy-assisted transoral resection was performed to resect the tumor. The tumor was a pedunculated lesion whose base arose from the right side of the nasopharynx, and was removed completely without major bleeding. There has been no recurrence so far. The present case indicates that NA needs to be included in the differential diagnosis of airway obstruction, especially in patients with communication difficulties caused by mental disorders.

Elongated styloid processes cause a variety of symptoms in the head and neck, and because of the diverse symptoms, accurate diagnosis may be difficult and appropriate treatment may be delayed. This report describes two cases of giant elongated styloid processes (Eagle’s syndrome). Case 1 was a 21-year-old man who presented with a 6-month history of right neck pain, and Case 2 was a 61-year-old man who presented with a 10-month history of neck pain and sore throat. In both cases, computed tomography revealed elongated styloid processes connecting to the hyoid bone. Surgical treatment using a transcervical approach was undertaken under general anesthesia. After the styloid processes were identified, they were resected and shortened by about 40 mm in Case 1 and by 70 mm in Case 2. Both the patients’ symptoms resolved immediately after the surgery. We suggest that three-dimensional computed tomography (3D-CT) is useful for the diagnosis and for planning the surgical procedure. Transcervical resection of an elongated styloid process is safe and effective, especially when the styloid process is extremely long and associated with complete ossification of the stylohyoid ligament.

Metastases to the thyroid cartilage are rare due to the absence of vessels within cartilaginous tissue. Herein, we report a rare case of thyroid cartilage metastasis in a patient treated for rectal cancer.

An 80-year-old male patient who had undergone low anterior resection for rectal cancer presented with multiple metastases. 9 months later, and underwent partial liver resection and pelvic tumor removal. One year after the first operation, he presented with throat pain and was found to have airway obstruction. Computed tomography of the neck showed a tumor in the thyroid cartilage. We performed tracheostomy and histopathological examination of the neck tumor revealed metastasis from rectal cancer. The thyroid cartilage metastasis gradually grew in size, the patient complained of pain, and we performed radiation therapy. The tumor shrank, however, other metastases increased in size, and the patient received palliative treatment.

Our review of the literature published between 1983 and 2021 revealed that the most frequently encountered metastatic cancer to the head and neck region from the thoracoabdominal viscera is metastasis of renal cancer to the paranasal sinuses, the most frequent primary lesion is in the kidney and the most frequent metastatic lesion is in the thyroid.

We report a case of subdural abscess secondary to abscess of the infratemporal fossa as a complication of odontogenic infection. The patient was an 84-year-old woman who was referred to our hospital because of swelling in her right temporal region and poor oral intake following extraction of the right lower jaw canine and first premolar teeth. Contrast-enhanced computed tomography revealed an infratemporal fossa abscess. Surgical drainage of the abscess was performed under general anesthesia via a temporal skin incision, and intravenous antibiotic therapy was initiated. Although there were no signs of active inflammation, three weeks after the surgery, contrast-enhanced magnetic resonance imaging revealed multiple subdural abscesses extending from the left temporal lobe to the frontal lobe. Thus, craniotomy was performed to drain the abscess. The patient discharged 32 days after the operation, without sequelae.

While treating an infratemporal abscess, it is necessary to consider the possibility of complication by intracranial abscess formation.

Tracheomalacia is a condition characterized by weakened tracheal walls, due to which the trachea collapses during expiration, resulting in dyspnea. Patients with severe motor and intellectual disabilities have many causes of tracheomalacia. They need to lie in bed for long periods; therefore, their chest wall becomes deformed and the thoracic vertebrae and brachiocephalic artery compress the trachea. In addition, they frequently develop aspiration pneumonia.

The patient was a 37-year-old man with spastic cerebral palsy who underwent surgical implantation of an intrathecal baclofen pump. He developed aspiration pneumonia after the intrathecal baclofen pump replacement and could not be weaned off the ventilator. We performed laryngotracheal separation (LTS) to prevent aspiration. One week after the LTS, the patient was taken off the ventilator, but he developed lower airway obstruction the same night. Tracheomalacia was confirmed by bronchoscopy. We treated the patient with antibiotics and positive pressure ventilation. No operation to expand the trachea was performed.

The patient had many causes of tracheomalacia, but had never developed lower airway obstruction. The findings suggests that the tracheomalacia was aggravated by the tracheal stoma. During spontaneous breathing, a positive end-expiratory pressure of approximately 3 to 5 cm H₂O is maintained during expiration to prevent alveolar collapse. When a tracheal stoma is present, that negative intrathoracic pressure is lost because the glottis cannot close properly. In tracheomalacia, the trachea may be obstructed by the loss of this small intrathoracic positive pressure, due to the loss of rigidity of the trachea. Patients who are asymptomatic but are at a high risk of tracheomalacia should be carefully monitored for asphyxiation after tracheostomy or LTS.

The number of infected and critically ill patients rose to a record high between July and September 2021 in Japan, with rampant transmission of the delta variant of the SARS-CoV-2 virus during the fifth wave of the coronavirus disease 2019 (COVID-19) pandemic. The increase in the number of critically ill patients was associated with a dramatic rise in the number of tracheostomies performed for patients on prolonged mechanical ventilation. We analyzed the data of 14 COVID-19 patients who underwent tracheostomy between August 2021 and September 2021. Eleven of the patients were men, and three were women. The average age was 48 years, and the average BMI was 30.8; four subjects had a BMI of ≥30, one had a BMI of ≥25 but <30, and eight had a BMI of <25. The procedure was performed in the operating room in 12 cases and in the ICU in 2 cases. To prevent infection, all the healthcare workers participating in the operations wore personal protective equipment, including an N95 mask and a face shield. The interval from the onset of COVID-19 to tracheostomy ranged from 21 to 46 days. None of the healthcare workers participating in the surgery contracted COVID-19. Where possible, performing a tracheostomy at 14–21 days or later after symptom onset in patients with COVID-19 can reduce the risk of infection in healthcare workers.

Infectious mononucleosis (IM), typically caused by the Epstein-Barr virus, is a commonly occurring, but self-limiting disease. However, its clinical findings and symptoms are very similar to those of tonsillitis or pharyngitis, and patients often receive treatment with antibiotics, which could result in the development of skin rashes or other side effects. However, the effect of antibiotic therapy for IM is still controversial; we have treated almost all our patients with IM by the same clinical pathway as that for acute tonsillitis or pharyngitis, which involves the use of antibiotics (ceftriaxone, clindamycin, or cefazolin). Therefore, we aimed to retrospective analysis of the data of our treated patients, aimed at improving our management of IM.

We analyzed the medical records of a total of 54 patients admitted to our department between 2013 and 2019, who met our diagnostic criteria for IM. The patients included 15 (27.8%) men and 39 (72.2%) women, ranging in age from 15–29 years (median 19 years), and the duration of hospitalization was 3–14 days (median 6 days). Pharyngeal culture was performed in 20 cases (37.0%), and pathogenic bacteria were isolated in 90% of cases. Thirty-nine patients (72.2%) had already received antibiotics before visiting our hospital; amoxicillin and cefditoren pivoxil were the most commonly prescribed (28.2%) antibiotics. The incidences of hepatic dysfunction and skin rashes were relatively low in patients who had received ceftriaxone, clindamycin, or cefazolin.

Amoxicillin use is known to be associated with a high incidence of skin rash in patients with IM, although our research demonstrated that patients who had received the antibiotic for less than 3 days were unlikely to develop skin rash. We believe that prescribing antibiotics to patients with IM is reasonable, and that especially when the diagnosis is still unclear, a very short course of amoxicillin is a helpful treatment option.

Gas gangrene is a progressive necrotizing soft tissue infection caused by bacteria. Cervical gas gangrene carries a poor prognosis, because of the risk of vital complications such as sepsis, disseminated intravascular coagulation, and descending necrotizing mediastinitis. We report a case of cervical gas gangrene that resolved leaving an intractable residual pharyngeal fistula. A 67-year-old man visited our hospital with the chief complaint of neck swelling. CT showed abscesses with gas, extending from the deep neck spaces to the mediastinum. We performed emergency transcervical and transthoracic drainage of the abscesses and tracheotomy, with administration of broad-spectrum antibiotics. At the same time, we also administered treatment to control glycemia, because the patient was severely diabetic. After drainage of the remaining abscesses and several sessions of debridement to remove the necrotic tissues, the patient recovered from the gas gangrene, but had an intractable residual pharyngeal fistula which failed to close even after two attempts at primary closure. We then sutured the fistula and covered it with a polyglycolic acid (PGA) sheet and fibrin glue. This led to effective closure of the fistula and the patient was discharged with moderate dysphagia. PGA is a biocompatible material that is used to cover mucosal defects. A PGA sheet not only useful to reinforce sutures, but also activates both proliferation of fibroblasts and formation of granulation tissue to enhance wound healing. Our results suggest that use of a PGA sheet is effective to close intractable pharyngeal fistula.

Adult-onset Still’s disease (AOSD) is a multisystemic autoimmune disease characterized by fever, arthritis, and skin rash, with negative test results for rheumatoid factor and antinuclear antibody. Diagnosis of AOSD is often difficult because of the lack of specific symptoms and laboratory findings.

We report the case of a 39-year-old woman with AOSD who presented to our Department of Otorhinolaryngology with fever and sore throat. The patient was treated with antibacterial drugs and a steroid for acute pharyngitis. During the steroid taper, the fever and sore throat flared up again, and the patient developed signs of liver damage, a skin rash, and arthralgia. She was suspected as having AOSD because of marked elevation of the serum ferritin level and negative tests for antinuclear antibody and rheumatoid factor. After ruling out infection, malignancy, and other collagen diseases, we confirmed the diagnosis of AOSD. The patient developed macrophage activation syndrome, which improved following treatment with immunosuppressive drugs and IL-6 antagonists.

Fever and sore throat are often treated as upper respiratory infection in the field of otorhinolaryngology. However, in patients with other systemic symptoms such as skin rash and arthralgia who also show a poor response to antibacterial drugs, it is essential to consider the possibility of AOSD in the differential diagnosis. The prognosis of AOSD is generally good; however, as the disease could become severe in some cases, it is necessary to collaborate with a rheumatologist as early as possible during the management of these patients.