Seiichi Nakata

Endolymphatic hydrops and blood-labyrinth barrier in Ménière's disease.

Abstract Conclusions: The blood–labyrinth barrier is impaired in association with the hydrops grade in Ménières disease. Objectives: To investigate the relationship between endolymphatic hydrops and the clinical characteristics of patients with Ménières disease revealed by 3 T magnetic resonance imaging (MRI). Methods: A double dose of gadoteridol (Gd; 0.2 mmol/kg) was injected intravenously in 12 patients with Ménières disease. We performed three-dimensional fluid attenuated inversion recovery MRI and three-dimensional real inversion recovery MRI 4 h later using a 3 T MRI unit. Ten patients had unilateral and two had bilateral Ménières disease. Results: Fourteen ears with Ménières disease showed intense Gd contrast on MRI compared with that in the 10 asymptomatic contralateral ears of patients with unilateral Ménières disease (1.12 ± 0.36 vs 0.82 ± 0.15). The hydrops grade was correlated significantly with the contrast effect. The 14 ears with Ménières disease had endolymphatic hydrops. Of the 10 contralateral ears of patients with unilateral Ménières disease, 2 had endolymphatic hydrops in the cochlea and 6 had endolymphatic hydrops in the vestibule.

Children with severe or moderate obstructive sleep apnoea syndrome show a high incidence of persistence after adenotonsillectomy

Abstract Conclusion: Persistent obstructive sleep apnoea syndrome (OSAS) occurs in approximately 20% of normal-weight children after adenotonsillectomy (T&A) and, in nearly 70% of them, it is caused by adenoid regrowth. Patients with severe or moderate OSAS showed a high incidence of persistent disease even after T&A. Allergic disease, severity and large adenoid size are associated with adenoid regrowth and persistent disease. Objectives: To investigate factors contributing to persistent OSAS and adenoid regrowth after T&A in normal-weight children. Methods: This was a prospective, observational study at a single institute and involved 49 normal-weight children with severe or moderate OSAS (apnoea–hypopnoea index, AHI, ≥ 5) who underwent T&A. Background information, nasal endoscopic data and pre- and postoperative polysomnographic data were collected. A third polysomnography (PSG) was performed 1.5 year postoperatively in children who subsequently developed symptoms of sleep disturbance. Results: Thirteen children (27%, 13/49) were symptomatic 1.5 years after T&A. Allergic rhinitis (38.5% vs 11.1%, p = 0.03) and allergic disease (69.2% vs 30.6%, p = 0.02) were seen more frequently in these children. A third PSG confirmed persistent disease (AHI ≥ 5) in nine children (18.4%, 9/49). Six children (12.2%, 6/49) were diagnosed as having adenoid regrowth and three (6.1%, 3/49) underwent revision adenoidectomy.

Craniofacial contribution to residual obstructive sleep apnea after adenotonsillectomy in children: a preliminary study.

STUDY OBJECTIVESnPediatric obstructive sleep apnea (OSA) is frequently associated with adenotonsillar hypertrophy, and the fact that about 30% of affected children continue to show OSA after adenotonsillectomy (AT) suggests the presence of some other predisposing factor(s). We hypothesized that abnormal maxillofacial morphology may be a predisposing factor for residual OSA in pediatric patients.nnnMETHODSnA total of 13 pediatric OSA patients (9 boys and 4 girls, age [median (interquartile range)] = 4.7 (4.0, 6.4) y, body mass index (BMI) z score = -0.3 (-0.8, 0.5)) who had undergone AT were recruited for this study. Maxillomandibular size was measured using an upright lateral cephalogram, and correlations between size and the apnea hypopnea index (AHI) values obtained before (pre AT AHI) and about 6 months after AT (post AT AHI) were analyzed.nnnRESULTSnAHI decreased from 12.3 (8.9, 26.5)/h to 3.0 (1.5, 4.6)/h after AT (p < 0.05). Residual OSA was seen in 11 of the 13 patients (84.6%) and their AHI after AT was 3.1 (2.7, 4.7)/h. The mandible was smaller than the Japanese standard value, and a significant negative correlation was seen between maxillomandibular size and post AT AHI (p < 0.05).nnnCONCLUSIONSnThese findings suggest that the persistence of OSA after AT may be partly due to the smaller sizes of the mandible in pediatric patients. We propose that the maxillomandibular morphology should be carefully examined when a treatment plan is developed for OSA children.The onset of restless legs syndrome (RLS) is usually progressive and the neural substrates underlying its pathophysiology remain to be identified. Here we report on a patient presenting with acute-onset RLS that was symptomatic of a right anteromedial pontine infarction. This case is exceptional because RLS appeared several hours before the occurrence of a regressive dysarthria clumsy-hand syndrome. Additionally, millimetric MRI sections showed that the structures possibly involved in RLS pathogenesis were the corticospinal tract, the pontine nuclei, and the pontocerebellar fibers. Although this is uncommon, clinicians should be aware that RLS characterized by a sudden onset can be a clinical manifestation related to stroke.

Evaluation of adenotonsillectomy and tonsillectomy for pediatric obstructive sleep apnea by rhinomanometry and the OSA-18 questionnaire

Abstract Conclusion: Nasal resistance and the OSA-18 score were useful for evaluating surgical treatments. The sleep disturbance score may also be useful for predicting the severity of obstructive sleep apnea (OSA) in children. Objective: We evaluated the effect of surgery on children with OSA using polysomnography (PSG) parameters, nasal resistance, and the OSA-18 questionnaire, and also investigated the cut-off OSA-18 score to screen for pediatric OSA. Methods: This was a retrospective study in which PSG parameters and nasal resistance were measured using a rhinomanometer and the OSA-18 score was obtained from the OSA-18 questionnaire before and after surgery in 45 children with OSA. Results: The mean age of the 45 patients was 5.7 ± 2.0 years. The mean value of the obstructive apnea hypopnea index (O-AHI) improved from 16.2 ± 14.3/h before surgery to 1.1 ± 1.7/h after surgery, the mean nasal resistance improved from 0.44 ± 0.19 to 0.32 ± 0.10 Pa/cm3/s, and the mean OSA-18 score improved from 61.1 ± 13.7 to 30.4 ± 5.8, and all these improvements were significant. The O-AHI value was lower than 1/h after surgery in 64.4% of patients (29/45). The O-AHI value was significantly correlated with the sleep disturbance score (r = 0.352, p = 0.018). When the cut-off OSA-18 score for screening was set at 40, sensitivity was 100%.

A functional variation in the hypocretin neuropeptide precursor gene may be associated with obstructive sleep apnea syndrome in Japan

To evaluate the association of hypocretin neuropeptide precursor gene (HCRT) variations with obstructive sleep apnea syndrome (OSAS) in a cohort of Japanese patients and to further evaluate whether the significant HCRT variations have potential functional consequences on HCRT expression.

Comparison of oxygen desaturation patterns in children and adults with sleep-disordered breathing.

PURPOSEnAlthough the number of apnea-hypopnea episodes per hour apnea-hypopnea index (AHI) is typically used to evaluate sleep-disordered breathing (SDB) in adults, it does not provide an accurate characterization of SDB in children. We investigated differences in SDB patterns in children and adults to evaluate SDB severity in children.nnnMATERIALS AND METHODSnFifteen adults (mean age, 45.3 ± 8.4 years) and 15 children (mean age, 6.7 ± 3.9 years) with adenotonsillar hypertrophy underwent standard polysomnography. The change of oxygen saturation (ΔSpO2) was defined as the difference between baseline SpO₂ during stable nighttime breathing and the lowest SpO₂ accompanied by an apnea-hypopnea event. The number of apnea-hypopnea episodes was determined using two different criteria to define an episode (criterion 1: cessation of airflow for at least 10s; criterion 2: cessation of airflow for at least two consecutive breaths).nnnRESULTSnMean ΔSpO₂ accompanied by obstructive apneas lasting ≤10 s was significantly greater in children than in adults, although there was no significant difference in the duration of apnea-hypopnea episodes. The slope of the regression line between ΔSpO₂ and apnea-hypopnea duration in children was greater than in adults (P<0.005). AHI in children was higher when calculated using criterion 2 compared to criterion 1 (10.9 ± 9.4 vs. 6.5 ± 4.9/h, P=0.003).nnnCONCLUSIONSnΔSpO₂ is a good indicator of SDB severity in children, and should therefore be considered in the diagnosis and treatment of pediatric SDB along with AHI.

Obstructive sleep apnea in Asian primary school children

PurposeThe objectives of this study were to examine the prevalence of obstructive sleep apnea (OSA) in primary school children, relationships between OSA and tonsillar hypertrophy, adenoid, and patency of the nasal cavity, and the effects of the tonsillar hypertrophy and adenoid on the nasal patency.MethodsAn examination of the palatine tonsils and anterior rhinoscopy, completion of a questionnaire survey, a measurement of nasal resistance, an examination for sleep apnea at home using portable polysomnography device, and radiography of pharyngeal tonsil were performed in 152 primary school children.ResultsThe obstructive apnea hypopnea index (O-AHI) increased with enlargements in the palatine tonsils. The adenoidal nasopharyngeal ratio (A/N ratio) decreased with advances in grade. A significant difference was observed in the O-AHI between those with and without adenoid. The median value of the O-AHI increased with advances in grade. The nasal resistance was significantly higher in the group with adenoid compared as in the group without. It was also higher in the nasal disease group with OSA than in the group without. Full polysomnography(PSG) was recommended in 16 (10.5xa0%) of 152 who underwent the examination using the portable polysomnography device, and of the eight who underwent PSG, six (75xa0%) were confirmed to have OSA, while its prevalence in all subjects was estimated as 7.9xa0%.ConclusionsDisturbances in nasal respiration as well as tonsillar hypertrophy and adenoid were found to be a risk factor of OSA in primary school children.

Case report of congenital cholesteatoma in the oval window and posterior mesotympanum surrounding a dehiscent fallopian canal in a young adult

Congenital cholesteatoma is defined as cholesteatoma occurring behind an intact tympanic membrane (TM). In the middle ear, it has different stages according to its site and relation with surrounding structures. We report an unusual case which is congenital cholesteatoma in the oval window and posterior mesotympanum surrounding a dehiscent fallopian canal in a young adult without obvious lesion behind intact TM, discussing its management. We have focused light in an unusual case in our practice and concluded that early intervention in such cases is recommended to prevent complications and planning a staged surgery is the treatment of choice.

Intranasal Transportation Phenomena of Medicinal Droplets

Nebulizer treatment has been used for nasal diseases such as paranasal sinusitis, hypertrophic rhinitis and inferior concha inflammation. The effectiveness of the nebulizer treatment has been confirmed from clinical view points until now. However there are a few researches that evaluate the effect of the nebulizer treatment quantitatively, i.e., how medicinal mist transports and deposits on inflammation areas of nasal wall. Some researchers calculated intranasal transport phenomena of medicinal droplets using Computed Fluid Dynamics (CFD). However these researches analyzed a few cases. The individual difference was left out of consideration even though there were different shapes of nasal cavities and different grade of medical conditions. This study constructs three-dimensional geometry model of nasal cavities using five actual patient’s CT data. The cases undergo deviated nasal septum, hypertrophic rhinitis, chronic sinusitis and bloating inferior nasal concha tumentia. This study analyzes the characteristics of airflow and medicinal droplet for the five cases and compared each other to get further knowledge of intranasal phenomena. As a result airflow velocity and pressure drop increase in the narrowing region caused by jet effect. Inlet angle and velocity of nebulizer treatment can easily control medicinal droplet transport characteristics. In the all cases the conditions of inlet angle 25-60 degree give us good treatment condition where medicinal droplet transports wide-area of nasal cavity. Especially this study makes clear circulatory flow is formed in superior concha. The circulatory flow is able to contribute advances medicinal droplet transportation in widespread area of intranasal.