To investigate the characteristic physical properties of the oscillating system in the intact middle ear using a high-speed camera.

We analysed the oscillation of the guinea pig stapes using a high-speed camera. The specimens were prepared so that the middle-ear structures were intact. Tones of various frequencies were delivered into the external auditory canal.

We found that the stapes showed a damped oscillation after the sound stimulation had stopped. The damped oscillation after the sound stimulation showed a specimen-specific frequency that was independent of the frequency of the stimulating sound. An injury to the bony labyrinth, which removed most of the mass from the oscillating system, attenuated the damped oscillation. Therefore, this damped oscillation is likely a passive motion, rather than a reverberation of the stimulating sound.

Analysing the passive damped oscillation may reveal the characteristic physical properties of the oscillating system in the near-intact middle ear. Further refinement of this simple and straightforward system may enhance basic and clinical research on the middle ear in a more intuitive way.

To investigate the pathogenesis of cholesteatoma, we planned to conduct a cohort study. As a first step, we conducted an epidemiological study in Fukuoka City, Japan to determine the incidence of cholesteatoma treated both with and without surgery. We also conducted a case–control study to investigate the pathogenesis of cholesteatoma.

The annual incidence of cholesteatoma, including cases treated without surgery, was 6.8–10.0 in a population of 100 000. The results of the case–control study suggested that a past history of otitis media and habitual sniffing caused by a patulous eustachian tube play a role in the pathogenesis of cholesteatoma.

The annual incidence of cholesteatoma, including cases treated without surgery, was considered to not be high enough to perform a cohort study. The results of the case–control study suggest that otitis media and habitual sniffing due to a patulous eustachian tube, contribute to the onset of cholesteatoma.

This project compares access to the anterolateral part of the jugular foramen provided by the lateral microsurgical preauricular and the anterior endoscopic approaches, and defines the important landmarks involved in each approach.

Cadaveric study.

The endoscopic transnasal/transmaxillary transpterygoid corridor provides a less invasive route for selected lesions in the jugular foramen than the traditional open route through the preauricular subtemporal infratemporal fossa approach. However, the anterior endoscopic approach provides a smaller channel to the jugular foramen than the preauricular approach.

The anterior endoscopic approach to the anterolateral part of the jugular foramen is a useful alternative to the lateral microsurgical preauricular approach in carefully selected cases. The vaginal process of the tympanic part of the temporal bone provides a valuable landmark to aid in accessing the jugular foramen in both procedures and can be drilled to open the foramen in the preauricular approach.

We used an artificial dermis (Terdermis®), which is an atero-collagen sponge covered with a sheet of silicon.

Nineteen ears of 17 patients with perforation of the tympanic membrane under various conditions, including large and wet perforations, underwent operation using this collagen sponge.

The success rate of closure after the initial surgery was 8/19. The overall success rate of closure after initial and re-operation was 14/19. The success rate of closure was 12/14 for small-sized perforations, 1/4 for middle-sized perforations and 1/1 for a large-sized perforation. Middle- and large-sized perforations required multiple surgeries. The success rate of closure was 11/11 for dry perforations, 3/4 for perforations with light otorrhoea and 0/4 for perforations with extensive otorrhoea.

This surgery is a low-cost and minimally invasive surgery and has a high closure rate. This surgery is effective on small-sized, dry perforations although it can also close middle- and large-sized dry perforations.

Our aim was to determine if stapes surgery is useful for treating inflammatory ear diseases.

Thirteen patients underwent single-stage or staged surgery for stapes fixation due to tympanosclerosis alone or with cholesteatoma. Operative criteria were: no tympanic membrane retraction, perforation or adhesion; middle-ear cavity with aeration >1 year; a fixed stapes. Computed tomography was used to analyse the relation between operative success and pre-operative pneumatisation.

Success rate at six months was 75 per cent. Hearing results were stable with little deterioration and no complications. Patients with poor pneumatisation had good results (with improved air–bone gap) only after staged surgery. Well-aerated ears heard better even with single-stage surgery.

Pre-operative computed tomography and intra-operative findings are necessary to determine the pneumatisation status of tympanic mastoid cavities. If criteria approved, poorly pneumatised patients underwent staged surgery. Stapedectomy achieved good hearing results for inflammatory middle-ear disease with stapes fixation.

We investigated the ossicular movement in the near-intact middle ear in response to acoustic stimulation using a high-speed video camera and video analysis software program.

We have designed a good visual access to the middle ear of the guinea pig by opening the ventral wall of the otic capsule, without injuring the sound-conducting structures, from the external auditory canal to the oval window. The high-speed video camera could record analysable ossicular motion up to 4000 frames per second.

The stapes showed reciprocal movement in the same frequency as the stimulating tone, and with an amplitude proportional to the stimulating sound intensity. Injury to the tympanic membrane attenuated the stapedial motion, which was recovered to that of the control level by patch repair of the perforation.

Our experimental set-up was capable of evaluating the conductive hearing, regardless of the status of the animal's sensorineural hearing or even life. Such a video analysis may provide a powerful tool to investigate the physiology of the middle ear.

Good outcomes have been reported regarding the use of cochlear implants for mumps deafness. The mumps virus induces meningitis and/or encephalitis, which can cause central nervous system damage resulting in retrolabyrinthine hearing loss, for which a cochlear implant would be less effective.

We installed a cochlear implant in two patients with bilateral mumps deafness; one achieved a good result with the cochlear implant, but the other did not. We discuss two possible reasons for the different outcomes. Case 1 was a three-year-old girl with bilateral parotid swelling, vomiting and walking disorder. One year after cochlear implant insertion, speech perception did not develop despite of good pure tone thresholds. Case 2 was an eight-year-old girl with bilateral parotid swelling. A cochlear implant enabled her to improve hearing perception.

Although cochlear implants have been reported to be helpful for mumps deafness, cases that involve central nervous system damage may not achieve good results.

Fibrous dysplasia is a bone disorder of unknown origin in which normal bone is replaced with fibrotic tissue and disorganised bone trabeculae. The temporal bone is rarely affected. Because of the slowly progressive course of the disease, many mild cases may never be recognised and are found incidentally. We present a patient with fibrous dysplasia of the right temporal bone, who had few complaints.

A 62-year-old man was incidentally found to have fibrous dysplasia of the temporal bone on routine computed tomography scan.

One case report.

Computed tomography showed a thickening of the right temporal bone with a ground-glass appearance. The 62-year-old man opted for watchful waiting.

We have presented an asymptomatic fibrous dysplasia of the temporal bone. Mild cases may never be recognised and are found incidentally because of their slow progression.

The present study investigates the indications for transnasal endoscopic surgery in treating post-operative maxillary cysts.

In this retrospective study, the records of 118 patients with post-operative maxillary cysts (88 unilateral and 30 bilateral) consisting of 148 procedures were reviewed.

A transnasal endoscopic approach was performed in 144 lesions (97.3 per cent). A combined endonasal endoscopic and canine fossa (external) approach was performed in 4 of 148 lesions, because the cysts were located distant from the nasal cavity and had a thick bony wall. A ventilation stent was placed in four patients (four cysts) to avoid post-operative meatal antrostomy stenosis. Recurrence was observed in five patients (4.2 per cent), all of whom subsequently underwent transnasal endoscopic revision surgery.

Transnasal endoscopic surgery is an effective treatment for post-operative maxillary cyst with the exception of cysts located distant from the nasal cavity.

The purpose of this study was to evaluate the effectiveness of the combination of inferior and middle meatal antrostomies for treatment of a maxillary sinus fungus ball by functional endoscopic sinus surgery.

A retrospective analysis including 28 patients with non-invasive fungal maxillary sinusitis was performed. Fourteen patients underwent FESS with both middle and inferior meatal antrostomies (combined group). The remaining 14 patients were treated with FESS through only the middle meatal antrostomy (control group).

Post-operative computed tomography showed normal maxillary sinuses in all patients in the combined group. In contrast, in the control group, five patients (36 per cent) exhibited a normal maxillary sinus, seven (50 per cent) showed maxillary mucosal thickening and two (14 per cent) had persistent fungus balls in the maxillary sinus.

FESS with a combination of middle and inferior meatal antrostomies proved more effective for treating fungal maxillary sinusitis.

The aim of this study was to determine whether allergic rhinitis can induce structural changes in the synapse formation in the hippocampus of BALB/c mice immunocytochemically.

Allergic rhinitis was induced in mice by two intra-peritoneal injections of ovalbumin administered with a one-week interval. After two weeks, the sensitised mice were challenged with an intra-nasal injection of ovalbumin for two weeks. To analyse the hippocampal synaptic structures, sections were immunostained with antibodies against glutamic acid decarboxylase 65 and glutamic acid decarboxylase 67 (for γ-aminobutyric acid-ergic terminals), synaptophysin (for glutamatergic and γ-aminobutyric acid-ergic terminals) and spinophilin (for dendritic spines). The number of nasal rubbing movements was significantly greater in the allergic rhinitis mice than in the control mice. However, the expression patterns of the four above-mentioned synaptic markers in the hippocampus showed no detectable difference between the allergic rhinitis and control mice.

These data indicate that the synaptic structure in the hippocampus might remain unaltered in allergic rhinitis patients.

Bone contouring is currently the best treatment for fibro-osseous lesions after bone growth arrest. Navigation systems available for this surgery allow intra-operative visualisation with improved cosmetic outcomes. However, conventional navigation systems using superficial skin registration cannot prevent subtle discrepancies.

To address this problem, we used a non-invasive cranial bone registration that uses patient-specific dental templates to maintain exact registration. We created the preset goal using the mirror image of the unaffected side for unilateral lesions, and using images obtained before the onset of symptoms for bilateral lesions. This system achieved precise pre-operative simulation. A sound aid in the navigation system provided information regarding proximity to critical structures and to the preset goal.

We used this system to contour fibro-osseous lesions in three patients. All patients achieved good facial contours and improvement in symptoms.

This method offers a safe, rapid surgical aid in treating orbital fibro-osseous lesions.

The purpose of the present study was to examine the clinical outcomes of using tracheoesophageal diversion for preventing intractable aspiration.

We retrospectively reviewed 25 patients who underwent tracheoesophageal diversion from 2003 to 2009 at our hospital (median age, 25 years; range, 0–78 years). End-to-side anastomosis was used in 16 cases and side-to-side anastomosis was used in 9.

The average operative time was 141 minutes for end-to-side anastomosis and 191 minutes for side-to-side anastomosis. Peri-operative complications were observed in only two (8 per cent) cases: one with infection and one with haematoma. No fistulas were observed. Aspiration was prevented in all cases, but the nutritional route depended on the swallowing function of the patient. Oral feeding was the main nutritional route after surgery in only four patients (16 per cent).

This procedure is well suited to patients who lack speech communication and are at high risk of aspiration.

In the present report, we describe the use of narrow band imaging during video-laryngomicrosurgery for laryngeal papillomatosis.

It is difficult to peri-operatively locate all the superficial papillomatous lesions when the disease is widespread, which then results in tumor recurrence. Therefore, we have constructed a narrow band imaging video-laryngomicrosurgery system, which we have used for two cases of laryngeal papillomatosis.

Our narrow band imaging-assisted video-laryngomicrosurgery system to visualise superficial laryngeal papillomatosis more clearly.

The object of this study was to analyse our experience with the effects of concurrent chemoradiotherapy for oropharyngeal squamous cell carcinoma, the treatment results of this therapeutic strategy and a salvage treatment for recurrent oropharyngeal squamous cell carcinoma.

Seventy-five patients with oropharyngeal squamous cell carcinoma were treated with chemoradiotherapy. The study included twenty-five of these patients who had recurrent oropharyngeal squamous cell carcinoma after chemoradiotherapy

The three-year actuarial survival rates for 75 patients by disease stage were as follows: stage II, 100 per cent; stage III, 71.1 per cent; stage IV, 51.7 per cent and overall, 58.2 per cent. The mean time of detection of recurrence was 6.2 months. The total salvage rates of recurrence were 21 per cent. The one and three-year tumour-free actuarial survival rates of those patients who received salvage treatment were 83 and 33 per cent.

Surgical salvage was only feasible for early recurrent tumour. Close follow-up surveillance of early recurrence is essential after primary treatment of patients with chemoradiotherapy.

The management of extrapulmonary small cell carcinoma has not been standardised to date. This study reviewed the clinical course, management and survival outcomes of patients with extrapulmonary small cell carcinoma in the head and neck region.

Nine patients with extrapulmonary small cell carcinoma in the head and neck were included in this study.

Five patients received radical surgery followed by adjuvant chemotherapy or radiotherapy or both. Two other patients were treated with chemotherapy consisting of CPT11 plus cisplatin or CPT11 plus cisplatin plus VP-16 three times. Two other patients received chemoradiotherapy consisting of S-1 or CPT11 plus cisplatin. The median overall survival was 14.5 months, with a three-year survival rate of 23.7 per cent.

The prognosis of extrapulmonary small cell carcinoma is generally poor. Further prospective multicentre studies are required for better understanding of disease entities and response to treatment modalities.

Liposarcomas rarely occur in the parapharyngeal space and only a few case reports exist. For curative therapy of liposarcoma, surgical excision remains the dominant modality. Although a wide surgical margin is important to prevent local recurrence, wide excision is often difficult in the head and neck region.

We report a case of a 19-year-old female with a well-differentiated liposarcoma arising in the parapharyngeal space. We removed the tumour surgically utilising a cervical–parotid approach. The histological diagnosis was well-differentiated sclerosing liposarcoma. There is no recurrence after five years and nine months of follow up.

The patient's age and the tumour site made it difficult for us to make a quantitative diagnosis before the operation. Well-differentiated liposarcoma rarely develop distant metastasis, but often recur locally. The benefit of adjuvant radiotherapy for well-differentiated liposarcoma is still not clear and careful and long-term follow up is necessary.

Adenosquamous carcinoma is a rare variant of semicircular canal that can affect various regions, including the head and neck. Adenosquamous carcinoma is characterised pathologically by the simultaneous presence of distinct areas of semicircular canal and adenocarcinoma, and usually takes an aggressive course with local recurrences, early lymph node metastases and distant disseminations.

We report a rare case of neck adenosquamous carcinoma of unknown primary origin, which was well-controlled by thorough resection without any other additional therapy.

We discuss the diagnosis and treatment of adenosquamous carcinoma along with a review of pertinent literature. We also consider the potential differential diagnosis of branchiogenic carcinoma.

Hyalinizing clear cell carcinoma is a rare minor salivary gland neoplasm. The treatment of choice is surgical resection with or without post-operative radiotherapy. This tumour often demonstrates a good prognosis.

We report a case of hyalinizing clear cell carcinoma arising in the nasopharynx. A 27-year-old female presented with progressive hearing disturbance and tinnitus. On examination, an expansile mass was observed in her nasopharynx. Biopsy was performed and the pathology results returned as clear cell carcinoma.

Surgical resection was performed trans-orally accompanied by trans-palatal approach. She has no recurrence during more than two years of follow up.