Keiji Honda

Audiovestibular findings in a branchio-oto syndrome patient with a SIX1 mutation

Abstract Conclusion: A reported mutation in SIX1 was identified in a patient with familial hearing loss (HL), a left preauricular pit, and bilateral enlarged vestibular aqueducts (EVA). Although the characteristic symptoms of EVA including fluctuating HL and repetitive vertigo were not seen in the patient, further studies are needed to clarify the association between EVA and such symptoms. Objectives: To study the audiovestibular functions, and to identify the causative gene in a patient with branchio-oto syndrome. Methods: We enrolled a 30-year-old female in whom HL was pointed out at the age of 6 years. She visited our department at the age of 21 years, and had not experienced any progression of her HL, tinnitus, or vertigo. Pure-tone audiograms showed bilateral moderate mixed HL with no apparent progression during a 9-year follow-up period. Audiovestibular examinations included distortion product otoacoustic emissions (DPOAEs), electrocochleography (ECochG), and electronystagmography (ENG). Direct sequencing was utilized to screen for SIX1, EYA1, SLC26A4, GJB2, and mitochondrial DNA MTRNR1 including 1555 position. Results: The findings of DPOAEs, ECochG, and ENG indicated cochlear HL with no vestibular dysfunction. A previously reported mutation of a heterozygous c.386A > G (p.Y129C) in SIX1 was detected. No mutation was identified in EYA1, SLC26A4, GJB2, or MTRNR1.

New Findings in Observations by Tubo-tympano-aerodynamic Method

We studied Eustachian tube function of healthy adults by two air flow methods, namely tubo-tympano-aerodynamic graphy by Valsalva maneuvre, and Tyonbee maneuvre during swallowing. We observed for the first time the presence of reciprocal features in normal Eustachian tubes. We also compared the tubal function of the same group using an air flow method and sound transmission method. The results of these observations showed that 77.4% of the subjects were positive for TTAG in Valsalva pattern, and 85.4% for sonometry. It can be inferred that data on the tubal opening in response to Valsalva and Toynbee maneuvres is obtained more easily by sonometry than by TTAG. TTAG, which permits examination of minute changes in air flow dynamics even in healthy Eustachian tubes, provides more important information on tubal function than does sonotubometry.

Ex vivo visualization of the mouse otoconial layer compared with micro-computed tomography.

Hypothesis Micro-computed tomography (micro-CT) is useful for assessing the 3-dimensional (3D) morphology and age-related changes of the otoconial layer. Background Wriggle mouse Sagami (WMS) is a mutant of the plasma membrane Ca2+ ATPase type2 gene (Atp2b2) with deficits in the saccular otoconia. We examined the effectiveness of micro-CT in evaluating the otoconial layer of WMS and C57BL/6J mice. Methods Otic capsules of C57BL/6J mice at different fixation time were examined using micro-CT to evaluate the effects of the fixation time on the otoconial layer. Otic capsules of Atp2b2wri/wri, Atp2b2wri/+, and Atp2b2+/+ mice at P14, P21, and the age of 3 months were used to analyze age-related changes in the otoconial layer. A series of cross-section and 3D reconstructed images of the otoconial layer were obtained. The micro-CT findings were compared with the otic capsule findings cleared in methyl salicylate using stereomicroscopy. Results Micro-CT produced high-resolution images of the otoconial layer, thereby providing information regarding the spatial configuration and 3D curvature. There were no changes between the different fixation times. In the Atp2b2wri/+ and Atp2b2+/+ mice, the saccular and utricular otoconial layers were normal among all age groups. In the Atp2b2wri/wri mice, the saccular otoconial layer decreased on P14 and was absent on P21, whereas the utricular otoconial layer disappeared at 3 months of age. Conclusion We obtained precise information regarding the mouse otoconial layer with minimum artifacts. This method is expected to improve our understanding of the physiologic function and age-related changes in otolith organs.

Progressive Encephalomyelitis with Rigidity and Myoclonus Resolving after Thymectomy with Subsequent Anasarca: An Autopsy Case

Progressive encephalomyelitis with rigidity and myoclonus (PERM) is an autoimmune disorder involving the brainstem and spinal cord and is sometimes associated with thymoma. We encountered a 75-year-old woman with typical PERM features, glycine receptor antibody, and thymoma. Her neurologic symptoms improved after thymectomy, but she unexpectedly developed anasarca with massive pleural effusions and hypoalbuminemia and finally succumbed to death. The autopsy showed edema and mononuclear infiltration in the pleura but no neuropathological findings typical of PERM. Effective treatment of PERM can reverse the neuropathological signs of encephalomyelitis. The autoimmune nature of anasarca is possible but not proven.

Increased expression of pendrin in eosinophilic chronic rhinosinusitis with nasal polyps

INTRODUCTION Chronic rhinosinusitis with nasal polyps is a heterogeneous disease and appropriate diagnostic algorithms in individual cases are necessary for effective medical treatment. OBJECTIVE The purpose of this study was to clarify the relationship between the pendrin expression of nasal polyps and clinical and pathological characteristic features of eosinophilic chronic rhinosinusitis. METHODS A total of 68 patients were classified into eosinophilic chronic rhinosinusitis or non-eosinophilic chronic rhinosinusitis groups according to the degree of eosinophilic infiltration into the nasal polyps. Clinical, hematological, and immunohistochemical analyses were performed and statistically compared between both groups. RESULTS Thirty-eight were classified into eosinophilic chronic rhinosinusitis and 30 into non-eosinophilic chronic rhinosinusitis groups. There were no significant differences in age distribution, sex ratio, prevalence of asthma, or any other complications between the groups. The mean Lund-Mackay score and the number of serum eosinophils was significantly higher in the eosinophilic chronic rhinosinusitis than in the non-eosinophilic chronic rhinosinusitis groups. The pendrin expression was more frequently detected in the epithelial surface layer of nasal polyps in the eosinophilic chronic rhinosinusitis than in the non-eosinophilic chronic rhinosinusitis groups. In addition, mucin 5AC was more widely expressed in the eosinophilic chronic rhinosinusitis than in the non-eosinophilic chronic rhinosinusitis. CONCLUSION Increased expression of pendrin and mucin 5AC in the nasal polyps would be associated with development of eosinophilic chronic rhinosinusitis. This finding could allow the development of a novel therapeutic agent targeted specifically to patients with eosinophilic chronic rhinosinusitis.

Measurement of middle ear ventilation with xenon gas - Normal subjects.

The ventilation and clearance of the middle ear were measured by radioisotope imaging techniques in order to gain a clear picture of the mechanism of ventilation. Radioactive xenon gas was insufhated into the middle ear of 9 normal subjects via the Eustachian tube, and observed by scinti camera. The volume was calculated with the passage of time. Approximately 11% of the insufflated gas immediately entered into the middle ear cavity and mastoid air cells in spite of the fact that the middle ear and mastoid air cells are a closed cavity. The gas in the middle ear diminished at a rate of 6% of volume per hour and it was thought to be absorbed mainly into the middle ear mucosa at a regular rate in the resting state.