A chirp stimulus is designed to compensate for the temporal dispersion in the cochlea related to the traveling wave delay. In response to a brief stimulus the cochlear traveling wave takes some time to propagate from the base of the cochlea to its apex. Therefore, the different neural units along the cochlear partition will not be stimulated at the same time and the neural activity across all nerve fibers will be smeared. This lack of temporal synchrony can be partly neutralized by an upward chirp stimulus, consisting of higher frequency components. The design of chirp stimuli must be based on a model of the cochlear delay. Chirp stimuli provide larger wave V amplitude compare with click stimuli.

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Primary macroglobulinemia is called Waldenström’s macroglobulinemia (WM), which is defined as lymphoplasmacytic lymphoma (LPL). The excessive and abnormal production of immunoglobulin M (IgM) monoclonal macroglobulin protein in bone marrow is characteristic of WM.
Clinical signs and symptoms are presented by hyperviscosity with excessive IgM protein disordering the vessel flow with sensory and motor peripheral neuropathy derived from the myelin-associated glycoprotein (MAG) in IgM.
The clinical features in the hyperviscosity syndrome are the different kinds of mucosal hemorrhage, retinal vein thrombosis and hemorrhage, headache, vertigo, hearing loss and so on. However, sensorineural hearing loss is rarely caused by WM, and WM with hearing loss has been reported only in eight studies to the best of my knowledge. Although the etiology of the hearing loss is unclear, but the past reports have concluded that the most probable of the cause of the hearing loss is the hyperviscosity syndrome and reported that hearing loss improved with plasma exchange treatment or chemotherapy.
We experienced a case which proved to be WM after the recovery of sensorineural hearing loss with steroid therapy followed by plasma exchange and chemotherapy. The patient reached remission status for the WM and the hearing loss has not recurred.

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A lateralized tympanic membrane is one of the complications that may arise after surgery of the middle ear. This is mainly due to the layer of skin associated with the tympanic membrane that is displaced outside the ring of the eardrum, and results in conductive hearing loss. As a method of treatment, surgery to return the tympanic membrane to the original position is usually performed, but the results are inconsistent. In many cases, a reconstructed tympanic membrane may become lateralized again when the surgery is performed. For these cases, we have developed a longer artificial ceramic columella to reconstruct the tympanic cavity without changing the position of the lateralized tympanic membrane. Better results have been shown during short-term observation of 6 months.

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Treatment targeting facial nerve schwannomas in the parotid gland have been controversial because of the occurrence of facial paralysis after excision. We experienced a single case of a facial nerve schwannoma in the parotid gland.
A 67-year-old woman was referred to us for evaluation of a tumor in the deep lobe of the left parotid gland that was detected by chance during magnetic resonance imaging at another department. Although excision of the deep parotid gland lobe was planned, a facial nerve schwannoma in the parotid gland was considered according to the preoperative and intraoperative findings. Only a biopsy was performed, after which the incision was closed. The pathological diagnosis was schwannoma. Although 2 years have passed since the operation, physical examination and magnetic resonance imaging findings have not revealed any aggravation.
Because postoperative facial palsy consequent to excision of a facial nerve schwannoma can remarkably reduce the quality of life, the goal should be function preservation to the greatest extent possible.

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The frontal sinus is prone to blockade because of the anatomical structure of its excretion path, the frontonasal duct, and it is often difficult to treat frontal sinusitis and frontal sinus cysts. When conservative management is ineffective, frontal sinus operations are performed via nasal endoscopes or an external approach, however, the incidence of postoperative recurrence is high. Obstruction of the front nasal duct causes stagnation of secretions in the frontal sinus, which may result in pressure necrosis of the sinus wall, and rarely, formation of a frontal sinus fistula on the forehead.
Herein, we report a patient with no history of operation or trauma who had refractory frontal sinusitis with a cutaneous fistula. The 60-year-old male had been diagnosed as having frontal sinusitis and undergone five operations over a period of eight years.

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In 2014, the Onodi cell was defined as the most posterior ethmoid cell which is situated laterally and/or superiorly to the sphenoid cell. It is closely connected to the optic nerve. So, if it is not recognized during endoscopic sinus surgery, it may result in some optic nerve injury or failure to open the sphenoid sinus.
The objective of the present study was to determine the prevalence of the Onodi cell and variations of the optic canal. Paranasal thin slice CT scans obtained from 237 patients in Osaka Kouseinenkin Hospital were analyzed. Patients with previous histories of facial trauma, paranasal sinus surgery or nasal cancer were excluded.
The prevalence of the Onodi cell was 27.4% (130 sides). The optic canal exposure types were classified into 4 groups: A: posterior ethmoid only; B: Sphenoid sinus only; C: posterior ethmoid and sphenoid sinus; and D: no exposure. Group A comprised 97 sides, group B 300 sides, group C 49 sides, and group D 28 sides. The prevalence of a pneumatized anterior clinoid process was 21.7% (103 sides). There was a significant correlation between the Onodi cell and sphenoid sinus and paranasal sinus lesions in the Chi-square test. Our data should prove useful in endoscopic sinus surgery. We must take care to avoid the optic nerve injury in patients with Onodi cell and a pneumatized anterior clinoid process.

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The adenomatoid odontogenic tumor (AOT) is a rare benign odontogenic tumor that is mostly found in jawbone. It is generally found in the incisor region of the maxilla of young females. It rarely extends into the paranasal sinuses. This article describes a case of AOT found in the maxilla and occupying the maxillary sinus and nasal cavity.
A 20-year-old woman was referred to our department because of swelling of the left cheek. CT examination showed a cystic lesion in the left maxillary sinus including calcified structures and an impacted tooth. A biopsy specimen of the lesion revealed an adenomatoid odontogenic tumor. We performed tumor extirpation combined with the Caldwell-Luc operation. There is no evidence of recurrence 3 years after the operation.

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We treated 62 cases of peritonsillar abscess between January 2011 and July 2014. The patients were classified into 2 groups according to whether the abscesses was located in the superior pole (superior pole group; 50 cases) or the inferior pole (inferior pole group; 12 cases). There were significant differences between the inferior pole group and superior pole group in the age of onset (52.6±6.6 vs. 39.5±2.6, P=0.04), leukocyte count (15900±1600/μl vs. 12800±5600/μl, P=0.02), degree of the laryngeal edema (58% vs. 22%, P=0.01), size of the retropharyngeal abscess (8% vs. 0%, P=0.04) and the percentage of patients needing drainage construction (33% vs. 88%, P<0.01).
In addition, all the patients were classified into four groups depending on the type of antimicrobial agents administerd, namely, the “penicillin” group, “penicillin or cephem plus clindamycin (CLDM)” group, “doripenem (DRPM)” group, and the “DRPM plus CLDM” group. We selected DRPM as the carbapenem antibiotic. All of the patients of the inferior pole group who were treated with DRPM with or without CLDM were cured. Three patients of the superior pole group were not cured with a penicillin, with or without CLDM.
The overall efficacy rates in the “penicillin” group, “penicillin or cephem plus CLDM” group, “DRPM” group, and “DRPM plus CLDM” group were 50%, 77%, 86% and 67%, respectively. There were significant differences in the efficacy between the “penicillin” group” and the other groups (P<0.01).
We concluded that a cephem/penicillin plus CLDM should be selected for the treatment of peritonsillar abscesses in the superior pole. For abscesses in the inferior pole, the selection of a carbapnem would be the more desirable for the purpose of preventing exacerbations. However, we need to revise the treatment policy from the viewpoint of proper use of antimicrobials.

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Schwannomas, which are tumors originating from the Schwann cells, are well-capsulated benign tumors, and are not common in the larynx. We describe the case of a 70-year-old woman with schwannoma of the epiglottis. The patient, who was scheduled to undergo mastectomy, was found to have a spherical mass in the larynx during intubation for general anesthesia. The mass was located on the pharyngeal aspect of the epiglottis. As she complained of a sense of incongruity of the pharynx, the tumor measuring 2 × 2 cm in size was completely resected by laryngomicrosurgery. Histopathology of the resected specimen revealed a laryngeal schwannoma. The nerve from which the tumor originated was uncertain. No recurrence has been noted during a follow-up period of more than 1 year.

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Patient profiles, compliance with palliative radiotherapy and the treatment outcomes were investigated in head and neck cancer patients who received palliative radiotherapy from 2006 to 2012. Clinicians selected patients who received palliative radiotherapy considering the clinical stage and the general body condition. There were no patients with severe acute or late toxicities during treatment and the completion rate of palliative radiotherapy was 79.3%. The palliative irradiation group showed significantly better overall survival rates as compared to the no-treatment group. Paliative irradiation of the primary tumor and lymph node metastases at the dose of over 50 Gy contributed to long-term disease-free survival and improvement of the quality of life (QOL), including reduction of tumorigenic pain and dysphasia. Thus, palliative radiotherapy may be a useful treatment option for patients with advanced head and neck cancer under the careful management.

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Introduction: The salivary duct carcinoma (SDC) is an uncommon aggressive malignant tumor of the salivary glands with frequent metastasis leading to a poor prognosis. SDC resembles high-grade breast ductal carcinoma and frequently overexpress human epidermal growth factor receptor-2 (HER-2). We report herein on a case of recurrent metastatic SDC treated with trastuzumab-based chemotherapy. A 77-year-old female was diagnosed as having a malignant tumor of the right parotid gland and underwent total parotidectomy and bilateral neck dissection. The resected tumor was histologically investigated and diagnosed as an SDC. No amplification of the HER-2 gene was found but overexpression of the HER-2 protein was detected (2+). Multiple metastases at the bilateral axillary and superior mediastinal lymph nodes were detected 10 months after surgery. We treated the patient with triweekly chemotherapy with a combination of trastuzumab and docetaxel for 4 cycles. However CT scan showed disease progression after chemotherapy. Conclusion: It is important to check out not only the overexpression of HER-2 protein with IHC, but HER-2 gene amplification also should be checked before trastuzumab-based chemotherapy for SDC.

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The surgical technique for Meniere’s disease is divided into 3 types, i.e., vestibular neurectomy, ablation of the vestibular potion of the labyrinth, and endolymphatic decompression. Approximately 40 years ago, when I began surgical treatment for Meniere’s disease, I preferred the decompression technique initiated by Georges Portmann because of the following reasons; first, this technique had continued uninterrupted for more than 40 years; second, the safety of this technique had been confirmed by many otologists; and third, the decompression technique seemed to be adaptable to our major consideration, i.e., improvement of hearing ability and prevention of hearing loss. In this paper, the 90-year-old technique pioneered by Georges Portmann is discussed from various points of view.

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