Fujinobu Tanaka

Investigation of Pharyngeal Swallowing Function Using High-Resolution Manometry

Objectives/Hypothesis: This study aimed to demonstrate the feasibility of a novel high‐resolution manometry system, and to establish normal values of swallowing pressures along the velopharynx and upper esophagus.

Effects of a tongue-holding maneuver during swallowing evaluated by high-resolution manometry.

Objective: This study aimed to investigate the effects of a tongue-holding maneuver (THM) during swallowing using a novel high-resolution manometry (HRM) system. Study Design: Case series with planned data collection. Materials and Methods: Thirty-three asymptomatic Japanese adults were studied. A solid-state HRM assembly with 36 circumferential sensors spaced 1-cm apart was positioned to record pressures from the velopharynx to the upper esophagus at rest and during swallowing. The maximum values of the dry swallowing pressures at the velopharynx, mesohypopharynx, upper esophageal sphincter (UES), and distance from the nostril to each point of maximum values with and without the THM were measured. Results: The distance from the nostril to the UES was statistically shorter when swallowing with the THM than without the THM (paired t test, P = 0.009). The maximum pressure at UES was greater when swallowing with the THM than without the THM, although there was no statistically significant difference (paired t test, P = 0.051). There was no difference in the pressures and the distance between swallowing with or without the THM at any other site. Conclusions: These findings suggest that the THM may not have a potential to facilitate compensatory swallowing power when swallowing.

Amplitude and area ratios of summating potential/action potential (SP/AP) in Meniere's disease.

Conclusions. Our results suggest that summating potential/action potential (SP/AP) area ratio may not necessarily have higher sensivity in the diagnosis of endolymphatic hydrops of Menieres disease (MD) than SP/AP amplitude ratio in transtympanic electrocochleography (ECochG). Objective. Recent studies suggested that SP/AP area curve ratio was more sensitive to endolymphatic hydrops in comparison with SP/AP amplitude ratio in extratympanic ECochG. The purpose of the present study was to evaluate the utility of the SP/AP area curve ratio in transtympanic ECochG for the diagnosis of MD. Patients and methods. A retrospective chart review of 198 patients (209 ears) was conducted in cases of MD. Results. With regard to SP/AP amplitude ratio, 57.1% in definite cases of MD (group 1), 39.6% in probable cases of MD (group 2), and 50.0% in the cases who had transformed from probable MD to definite MD (group 3) showed abnormally high values, respectively. Abnormally high values were observed in 43.9%, 27.7%, and 30.0% in SP/AP area ratio in groups 1, 2, and 3, respectively, indicating that abnormal values were observed more frequently in the amplitude ratio than in the area ratio in all three groups.

GJB2-associated hearing loss undetected by hearing screening of newborns.

The hearing loss caused by GJB2 mutations is usually congenital in onset, moderate to profound in degree, and non-progressive. The objective of this study was to study genotype/phenotype correlations and to document 14 children with biallelic GJB2 mutations who passed newborn hearing screening (NHS). Genetic testing for GJB2 mutations by direct sequencing was performed on 924 individuals (810 families) with hearing loss, and 204 patients (175 families) were found to carry biallelic GJB2 mutations. NHS results were obtained through medical records. A total of 18 pathological mutations were identified, which were subclassified as eight inactivating and 10 non-inactivating mutations. p.I128M and p.H73Y were identified as novel missense GJB2 mutations. Of the 14 children with biallelic GJB2 mutations who passed NHS, eight were compound heterozygotes and 3 were homozygous for the c.235delC mutation in GJB2, and the other three combinations of non-c.235delC mutations identified were p.Y136X-p.G45E/p.V37I heterozygous, c.512ins4/p.R143W heterozygous, and p.V37I/p.R143W heterozygous. These 14 cases demonstrate that the current NHS does not identify all infants with biallelic GJB2 mutations. They suggest that the frequency of non-penetrance at birth is approximately 6.9% or higher in DFNB1 patients and provide further evidence that GJB2 hearing loss may not always be congenital in onset.

Superficial Siderosis of the Central Nervous System

This is a case of superficial siderosis of the central nervous system (SSCN). The diagnosis of SSCN was based on the result of T2-weighted magnetic resonance imaging and on suggestive clinical manifestations. The pure-tone audiogram showed bilateral progressive sensorineural hearing loss with a poor speech discrimination score and Jerger type IV. The remarkable elevation of the detective threshold of cochlear microphonics on electrocochleography was found and distortion product otoacoustic emission (DPOAE) showed no response: These electrophysiologic examinations, including electrocochleography and DPOAE, revealed that the progressive sensorineural hearing loss in this case was caused by both retrocochlear and cochlear damages.

Influence of topical application of basic fibroblast growth factor upon inner ear

Background Basic fibroblast growth factor (b-FGF) has recently been shown to have a positive effect on the treatment of postoperative mastoid cavity problem, but its ototoxicity has not been investigated. Objective To investigate the effect of b-FGF on the inner ear of guinea pigs. Study Design and Setting In groups A (n = 10) and B (n =11), b-FGF was applied into the left external auditory canal and the middle ear, respectively. The right ear served as a control. At 1 week after b-FGF administration, the endocochlear DC potential (EP) was measured, and morphology of the cochleae was examined by scanning electron microscopy. Results In group A, the EP values of experimental ears and controls were 90.0 ± 8.4 (mV, mean ± SD) and 89.4 ± 4.3 (P < 0.05). In group B, the values were 86.5 ± 11.4 and 87.5 ± 6.1, respectively, (P < 0.05). Morphological findings showed no damage on the cochlear. Conclusion Application of b-FGF to the external and middle ears does not seem to have an apparent risk of ototoxicity.

Does topical application of 5-fluorouracil ointment influence inner ear function?

OBJECTIVE: To investigate the effect of 5-fluorouracil (5-FU) ointment on the inner ear of guinea pigs. STUDY DESIGN AND SETTING: In group A (n = 7), 5-FU ointment was applied into the left external auditory canal. In group B (n = 10), 5-FU ointment was applied to the left middle ear through myringotomy. In both groups, the right ear served as a control. One week later the endocochlear DC potential (EP) was measured and morphology of the cochleae was examined using scanning electron microscopy (SEM) and light microscopy. RESULTS: In group A, there was no significant difference between the EP values of the experimental side and the control side. In group B, there was a statistically significant difference between them (P < 0.05). Morphologic findings showed no damage. CONCLUSION: 5-FU ointment application to the external ear seems to be safe but its application to the middle ear may pose some risk of ototoxicity.

Microbiomes of the normal middle ear and ears with chronic otitis media

The aim of this study was to profile and compare the middle ear microbiomes of human subjects with and without chronic otitis media.

Measurement of the endolymphatic sac potential in human.

In this study, we measured human endolymphatic sac potential (ESP) in 8 patients with vestibular schwannoma and in five patients with Ménières disease during surgery. ESP was measured with a glass electrode filled with 154 mM NaCl and with an outside tip diameter ranging from 2 to 3 microm. The mean value of human ESP in patients with vestibular schwannoma was +13.3+/-1.9 mV. Since electron microscopy showed that the endolymphatic sacs of the eight patients with vestibular schwannoma were normal in the ultrastructures the value can be close to normal human ESP. While in Ménières disease, three cases showed low potentials and two cases showed almost the same values observed as in the eight patients with vestibular schwannoma. In the two cases with Ménières disease, the epithelial cells of the endolymphatic sac were preserved. Our study can be considered as the first successful measurement of human ESP and revealed the existence of Ménières disease having normal endolymphatic sac in function as well as morphology.

Vocal Hygiene Education Program Reduces Surgical Interventions for Benign Vocal Fold Lesions: A Randomized Controlled Trial: Effect of Reinforced Vocal Hygiene Education

Vocal fold polyps and nodules are common benign laryngeal lesions. Currently, the Japanese health insurance system covers surgical interventions. However, the establishment of more cost‐effective conservative methods is required, because healthcare costs are viewed as a major concern, and the government and taxpayers are demanding more economical, effective treatments. In this situation, more suitable vocal hygiene education may be important for the success of cost‐effective conservative treatment. In this study, we developed a novel reinforced vocal hygiene education program and compared the results of this program with those of previous methods of teaching vocal hygiene.