Application of machine learning in the diagnosis of vestibular disease.

Machine learning is considered a potential aid to support human decision making in disease prediction. In this study, we determined the utility of various machine learning algorithms in classifying peripheral vestibular (PV) and non-PV diseases based on the results of equilibrium function tests. A total of 1009 patients who had undergone our standardized neuro-otological examinations were recruited. We applied five supervised machine learning algorithms (random forest, adaboost, gradient boosting, support vector machine, and logistic regression). After preprocessing the data, optimizing the hyperparameters using GridSearchCV, and performing a final evaluation on the test set using scikit-learn, we evaluated the predictive capability using various performance metrics, namely, accuracy, F1-score, area under the receiver operating characteristic curve, precision, recall, and Matthews correlation coefficient (MCC). All five machine learning algorithms yielded satisfactory results; the accuracy of the algorithms ranged from 76 to 79%, with the support vector machine classifier having the highest accuracy. In cases where the predictions of the five models were consistent, the accuracy of the PV diagnostic results was improved to 83%, whereas it increased to 85% for the non-PV diagnostic results. Future research should increase the number of patients and optimize the classification methods to obtain the highest diagnostic accuracy.

Long-term effect of transtympanic intermittent pressure therapy using a tympanic membrane massage device for intractable meniere's disease and delayed endolymphatic hydrops.

BACKGROUND: A 12-month follow-up study showed that middle ear pressure treatment with a transtympanic membrane massage (TMM) device had a similar effect to a Meniett device. OBJECTIVES: The effects of pressure treatment with a TMM device were retrospectively compared to the effects of treatment with a Meniett device in patients with Meniere's disease (MD) and delayed endolymphatic hydrops (DEH) who were followed for a minimum of 24 months. MATERIALS AND METHODS: Twenty-seven patients were treated with the TMM device and 14 patients were treated with a Meniett device. The insertion of a transtympanic ventilation tube was necessary for the Meniett device but not for the TMM device. RESULTS: In patients treated with the TMM and Meniett devices, the frequency of vertigo significantly improved at 19-24 months after treatment. The distribution of vertigo at 19-24 months after treatment did not differ between the patients treated with the two types of devices. Pressure treatment for 8 months or more was suitable to achieve remission. CONCLUSIONS AND SIGNIFICANCE: Middle ear pressure treatment for 8 months or more with a TMM or Meniett device was equally effective and provided minimally invasive treatment options for intractable MD and DEH.

Effects of transtympanic intermittent pressure therapy using a new tympanic membrane massage device for intractable Meniere's disease and delayed endolymphatic hydrops: a prospective study.

BACKGROUND: The retrospective study showed that the effect of the middle ear pressure treatment by the tramstympanic membrane massage (TMM) device was similar to that of the Meniett device. OBJECTIVES: The new TMM device named EFET device was prospectively evaluated in patients with Meniere's disease (MD) and delayed endolymphatic hydrops (DEH) and we compared the effects to the Meniett device. MATERIALS AND METHODS: 23 ears of 19 patients were treated with an EFET device, and 17 ears of 15 patients were treated with the Meniett device. All patients suffering from intractable MD and DEH were treated for 4 months. The insertion of a transtympanic ventilation tube was necessary for the Meniett device, but not the EFET device. RESULTS: In patients treated by the EFET and Meniett devices, the frequency of vertigo significantly improved after treatment. The distribution of vertigo outcomes at 4 months after treatment did not differ between patients treated with the both devices. CONCLUSIONS AND SIGNIFICANCE: Middle ear pressure treatment by the EFET device is effective and provides minimally invasive options for intractable MD and DEH like the Meniett device.

Japanese standard for clinical stabilometry assessment: Current status and future directions.

Stabilometry is a useful tool for examining patients with functional disorders of the vestibular system. However, measurement techniques and devices vary by country. Therefore, international standardization of stabilometry is mandatory to validate the exchange of important findings. This was advocated at the 1983 Posturography Meeting in Kyoto but has not been adopted worldwide, and each country has continued to use unique regional measurement methods. In Japan, stabilometry has widespread application in medical practice in conjunction with research into its applications. With a goal of international standardization, we present details of stabilometry measurement methods and their application in Japan, together with a brief history and potential future directions of stabilometry.

Classification, diagnostic criteria and management of benign paroxysmal positional vertigo.

Benign paroxysmal positional vertigo (BPPV) is the most common peripheral vertigo and the posterior and/or lateral semicircular canals are usually affected. BPPV is characterized by brief attacks of rotatory vertigo associated with positional and/or positioning nystagmus, which are elicited by specific head positions or changes in head position relative to gravity. In patients with the posterior-canal-type of BPPV, torsional nystagmus is induced by the Dix-Hallpike maneuver. In patients with the lateral-canal-type of BPPV, horizontal geotropic or apogeotropic nystagmus is induced by the supine roll test. The pathophysiology of BPPV is canalolithiasis comprising free-floating otoconial debris within the endolymph of a semicircular canal, or cupulolithiasis comprising otoconial debris adherent to the cupula. The observation of positional and/or positioning nystagmus is essential for the diagnosis of BPPV. BPPV is treated with the canalith repositioning procedure (CRP). Through a series of head position changes, the CRP moves otoconial debris from the affected semicircular canal to the utricle. In this review, we provide the classification, diagnostic criteria, and examinations for the diagnosis, and specific and non-specific treatments of BPPV in accordance with the Japanese practical guidelines on BPPV published by the Japan Society for Equilibrium Research.

A Case of Infantile Large Parapharyngeal Rhabdomyosarcoma Followed Up for More Than 20 Years.

Rhabdomyosarcomas in the parapharyngeal space are quite rare. We report herein on the case of a 14-month-old boy who was hospitalized with a 2-month history of stridor. On admission, right peritonsillar swelling was noted. CT demonstrated the presence of a large tumor in the right parapharyngeal space. MRI findings showed a right parapharyngeal tumor, 6-cm in diameter. Histopathologic evaluation of the tumor revealed embryonal rhabdomyosarcoma. The clinical staging of the Intergroup Rhabdomyosarcoma Study Group (IRSG) was classified as group III. According to regimen 35 of the IRSG III treatment protocol, radiochemotherapy was started, comprising combination therapy with vincristine, actinomycinD, cyclophosphamide, adriamycin, and carboplatin. The patient tolerated the therapy, but with severe pancytopenia and fever. His sedation during irradiation was difficult. After he received a total dose of 10 Gy and had undergone 9 cycles of chemotherapy, an operation for the rhabdomyosarcoma was performed, resulting in successful removal of the tumor. Doses of 20 Gy were intraoperatively administered. After surgery, residual chemotherapy and irradiation was resumed. The evaluation of the response to therapy was complete remission. After 4 years from the start of therapy, all chemotherapy was halted. At present there is no evidence of recurrence or metastasis, and the patient is a well-developed college student. His sequela following therapy consisted of facial asymmetry, dental abnormalities, and pigmentation of the neck. No adriamycin cardiomyopathy was found.

Intermittent pressure therapy of intractable Meniere's disease and delayed endolymphatic hydrops using the transtympanic membrane massage device: a preliminary report.

CONCLUSION: Middle ear pressure treatment by the tympanic membrane massage (TMM) device as well as the Meniett device is effective and provides minimally invasive options for intractable vertigo in patients with Meniere's disease (MD) and delayed endolymphatic hydrops (DEH). OBJECTIVE: The effects of the TMM device were evaluated according to the criteria of the Japan Society for Equilibrium Research (1995) in patients with MD and DEH and compared to those in patients treated with the Meniett device. METHODS: Twelve ears of 10 patients (MD 8; DEH 2) were treated with the TMM device, while 16 ears of 15 patients (MD 11; DEH 4) were treated with the Meniett device. All the patients had failed to respond to medical treatment including diuretics before each pressure treatment, and were followed up for more than 12 months after treatment. Tympanotomy is necessary before treatment for the Meniett device, not but for the TMM device. RESULTS: With both devices, the frequency of vertigo after treatment was significantly lower than before treatment (p < 0.05). The time course of vestibular symptoms with the TMM device was not significantly different from that with the Meniett device (p > 0.05). No complications were directly attributable to treatment with the TMM device.

Foreign body aspiration in children: a nationwide survey in Japan.

BACKGROUND: Foreign body aspiration (FBA) is a common cause for a respiratory emergency in young children and can be a life-threatening event. We, therefore, conducted the first nationwide survey in Japan. METHODS: We asked doctors of 261 tertiary hospitals across the nation to fill out a case card of FBA-diagnosed cases they had experienced for the past 2 years. In the case card, age and gender of the patients, elapsed time until being referred to the hospital, presenting symptoms, previous diagnosis, suspected aspiration episode, type and location of aspirated foreign body, and consequences were inquired. This retrospective survey was carried out during 21 months, since January 2005 through September 2006. RESULTS: Replies from 169 hospitals (64.8%) revealed that 163 cases of FBA had been treated in 114 hospitals during the past 2 years. Median age of cases was 1 year (2 months to 15 years), and 66.5% were male. Only 50.9% of the cases were referred to hospitals within 24h. Comparing these early-diagnosed cases, children with delayed diagnosis had similar age and sex distribution. In respect of presenting symptoms, characteristic ones such as choking or dyspnea were observed significantly more often in the early-diagnosed cases, whereas significantly predominant symptoms in children with delayed diagnosis were non-specific ones like coughing and wheezing (both, p<0.05). Although significantly more cases with early diagnosis reported suspected aspiration episodes (p<0.05), even in the delayed diagnosis group more than half cases (65%) had suspected episodes as well. Severe consequences occurred in seven cases (4.3%): four cases of irreversible hypoxic brain damage and one death due to multiorgan failure in the early diagnosis group; one bronchiectasis and one recurrent pneumonia in the delayed diagnosis group. CONCLUSIONS: Characteristics of FBA among children in Japan were not substantially different from the reports from other countries. Suspected episodes were important, and there were some differences in presenting symptoms between early and delayed diagnosis cases. However, there are still no key sings to make a prompt diagnosis. In order to prevent FBA and make a timely diagnosis, continuous and extensive educational programs should be provided.

[A case of laryngeal sarcoidosis difficult to diagnose].

Sarcoidosis is a multiorgan granulomatous disease of unknown cause, named after the characteristic histopathological findings of the disease. In this article, we shall report a case in which biopsy needed to be repeated three times until a final diagnosis of laryngeal sarcoidosis could be made. Since sarcoidosis associated with only a laryngeal pathology may not be associated with any laboratory abnormalities in many cases, first priority should be attached in suspected cases to detect the presence of noncaseating epithelioid cell granulomas. In this case, the results of the first and second laryngeal biopsies did not show non-caseating epithelioid cell granulomas, while the third biopsy showed noncaseating epithelioid cell granulomas with giant cells. Finally, the diagnosis of laryngeal sarcoidosis was made after the results of whole-body imaging became available. Laryngeal sarcoidosis must be borne in mind as a suspected diagnosis in cases where the larynx shows yellowish-white diffuse swelling.

Mumps virus infection in adults: three cases of supraglottic edema.

Mumps virus infections primarily involve the parotid glands and most frequently affect school-aged children. We present three unusual adult cases of mumps with dyspnea secondary to severe swelling of the salivary glands and review previously reported cases in the literature. Dyspnea developed progressively after the onset of salivary gland swelling. Laryngoscopy revealed an advanced edematous change in the supraglottis obstructing the airway. In two cases, tracheotomy was needed because of rapid worsening of the supraglottic edema. Questioning regarding breathing problems and laryngoscopic examination is therefore recommended when one encounters a mumps case with combined parotid and salivary gland swelling.

Head and body sway in response to vertical visual stimulation.

CONCLUSIONS: Postural responses differed according to the stimulus direction, i.e. vertical visual stimulation induced head rather than trunk displacements. Accordingly, it could be that center of foot pressure (COP) responses tended to underestimate the postural sway during visual stimulation. OBJECTIVES: To investigate head and body sway in response to vertical visual surround motion, and to examine the correlation between the displacements of head and body segments derived from video-motion analysis and COP measurements. MATERIAL AND METHODS: Postural sway was assessed in 10 young female subjects by video-motion analysis of four different head and body segments, and by use of force-plate posturography. Head and body sway in the pitch plane was induced by rotating a random pattern of dots about the subject's inter-aural axis at a constant acceleration of 1 degree/s(2) or a constant velocity of 60 degrees/s in darkness. RESULTS: Generally, head displacement was greater than that of other body parts during vertical optokinetic stimulation (OKS). In most subjects, maximum head displacements were induced in the same direction as the visual motion. Downward OKS induced a forward head and body sway. The COP trajectory correlated well with the displacements of each head and body segment during downward OKS. In contrast, postural responses to upward OKS were complicated in terms of their time course. The correlation coefficient between each head and body segment and the COP varied among individuals for upward OKS.

Influence of visually induced self-motion on postural stability.

CONCLUSION: Our results indicate that the illusion of self-motion is a significant factor leading to spatial disorientation. OBJECTIVE: Under normal circumstances, self-motion is perceived in response to motion of the head and body. However, under certain conditions, such as virtual reality environments, visually induced self-motion can be perceived even though the subject is not actually moving, a phenomenon known as "vection". The aim of this study was to examine the possible influence of illusory self-rotation (circular vection) on postural adjustments. MATERIAL AND METHODS: The subjects were 10 young females with no history of ocular or vestibular disease. Video-motion analysis was applied to measure postural movements during vertical optokinetic stimulation. RESULTS: For most subjects, movement of the visual surroundings induced head and body displacements in the same direction as that of the visual stimulus, regardless of the onset of self-motion perception. However, there was a significant increase in postural instability after the subjects began to perceive false self-motion in the opposite direction to that of the visual stimulus.

[Neurotological long-term follow-up in Minamata disease in Niigata, Japan].

To determine the long-term influence of organic mercurial intoxication on audiological and equilibrium findings, we followed up 36 patients neurotologically during 1980-1987 and 1991-2000 at Kido Hospital in Niigata. Typical findings were as follows: 1. In pure-tone audiometry, 24 of 72 ears (33%) showed slight hearing deterioration and 3 (4%) showed improvement. 2. Spontaneous nystagmus had disappeared in 5 patients (14%), but appeared in new 13 patients (36%). Positional nystagmus did not improve in any patient, and deteriorated in 11 (31%). 3. In optokinetic nystagmus (OKN) tests, especially in vertical OKN test showing significant deterioration (44%). 4. The caloric nystagmus test showed marked deterioration (47%). Body-equilibrium testing showed slight deterioration in 11 patients (31%) and improvement in 5 (14%). Neurotological findings thus varied widely among patients and we were concluded that these differences were caused both by duration of methyl mercury contamination and by aging factors in patients.