Yu Yuasa

Postoperative results of simple underlay myringoplasty in better hearing ears.

Conclusions. Simple underlay myringoplasty with fibrin glue (SUM) is indicated for repair of tympanic membrane (TM) perforation in the better hearing ear because postoperative hearing deterioration is extremely rare. Objective. To evaluate the postoperative results, including the hearing and the re-perforation rate, in the better hearing ear. Materials and methods. The procedure of SUM is removal of the perforation edge and bonding of the graft to the remnant TM with a few drops of fibrin glue by underlay technique. This method was applied to 75 patients with a perforated TM in the better hearing ear. The postoperative hearing and the re-perforation rate were investigated. Results. The mean of the postoperative hearing gain was 10.3 dB and no cases of postoperative hearing loss were observed. Although postoperative re-perforation was found in 18 cases (24.0%), the re-perforation was closed in 16 of these cases in the outpatient department by the same procedure using frozen autologous tissue that had been harvested previously in surgery. Including these cases, the total success rate was 97.3%.

Measurement of stapes mobility in guinea pigs and rabbits

In tympanoplasty, it is essential to know the condition of the stapes. However, it has been difficult to evaluate stapes mobility in routine measurement. With the eye on improving future clinical practice, in this study we developed a new, easy system of measuring stapes mobility quantitatively and, as a first step, applied it to measurement of the relationship between the load and displacement of the stapes in guinea pigs and rabbits. The stapes displacement increased linearly with an increase in load in the small displacement region, and increased nonlinearly in the large displacement region. The slope of the regression line of this stiffness curve in the small displacement region was used as an index of the stapes mobility. The values in the guinea pigs and rabbits were 16+/-7 N/m and 115+/-25 N/m, respectively. A significant difference between the two species was observed.

Habitual sniffing and postoperative configuration of the posterior meatal wall reconstructed with soft tissue

Conclusions. Habitual sniffing is a significant contributing factor to the development of postoperative retraction of the reconstructed posterior meatal wall and tympanic membrane, although it still seems a multifactorial event. Objective. To examine the possible contribution of habitual sniffing to retraction-type middle ear pathology in a more direct way than previous reports. Patients and methods. The correlation between habitual sniffing and the postoperative configuration of the posterior meatal wall was examined in 58 patients with cholesteatoma who underwent tympanoplasty with reconstruction of the soft meatal wall. Results. The postoperative configuration of the posterior meatal wall showed severe retraction in 7 of 8 patients with habitual sniffing, but only 22 of 47 without habitual sniffing. Habitual sniffing was significantly associated with postoperative severe retraction (Fishers exact test, p<0.05).

An apparatus for diagnosis of ossicular chain mobility in humans

Confirmation of the conditions of the ossicles is essential for tympanoplasty. However, at present, ossicular mobility is experimentally estimated with palpation by a surgeon, and the results depend on the surgeons skill. In this study, a new apparatus for quantitatively measuring ossicular mobility was developed. With this apparatus, the ossicles were displaced and the reaction force from the ossicles, (i.e. the load applied to the ossicles) was simultaneously detected. Ossicular mobility of three patients with otosclerosis or chronic otitis media was measured to evaluate the usability of the apparatus. The apparatus can distinguish the differences in ossicular mobility between normal and fixed ossicles, and it makes estimating the change of mobility between pre- and post-treatments for ossicular fixation possible. Positive correlation was seen between ossicular mobility and hearing level. Sumario La confirmación de la movilidad osicular es esencial para la timpanoplastia; sin embargo, actualmente se estima experimentalmente por medio de palpación por parte del cirujano y el resultado depende de la destreza del mismo. En este estudio se desarrolló un nuevo aparato para medir cuantitativamente la movilidad osicular. Con este aparato, los huesecillos son desplazados y su fuerza de reacción, p.e. la carga que se les aplica, es detectada simultáneamente. Se midió la movilidad osicular de tres pacientes con otoesclerosis u otitis media crónica para evaluar la utilidad del aparato. El aparato puede distinguir entre movilidad normal o huesecillos fijos, y da un estimado de cambio de movilidad pre y post-tratamiento. Se observó una correlación positiva entre la movilidad osicular y el nivel de audición.

Effects of hearing level on habitual sniffing in patients with cholesteatoma.

Conclusions. Quality of hearing is one of the key conditions promoting habitual sniffing associated with closing failure of the Eustachian tube and sniffing may stop with deterioration of hearing due to progression of the disease. Objective: To examine habitual sniffing associated with closing failure of the Eustachian tube and hearing level in patients with cholesteatoma. Patients and methods. A total of 171 patients with middle ear cholesteatoma treated in Tohoku University Hospital (106 sides in 101 patients, 63 males and 38 females, mean age 43.3 years), and Sendai Ear Surgi Center (70 sides in 70 patients, 37 males and 33 females, mean age 42.7 years) were included. The patients were divided into two groups based on the presence or absence of habitual sniffing, and pre- and postoperative hearing was compared between the two groups. Results. Habitual sniffing was not found in patients with air conduction hearing level worse than 60 dB or air–bone gap larger than 40 dB. Habitual sniffing disappeared in all patients with expanded air–bone gaps in lower frequency regions after surgery.

Sound Localization for a Virtual Sound Source in Cases of Chronic Otitis Media

Sound localization in subjects with chronic otitis media (COM) was examined before and soon after ear surgery by means of virtual sound presented by headphones, sound being synthesized based on the head-related transfer functions (HRTFs) in a normal subject. The localization ability in COM patients was usually worse than that in normal subjects, but was better than expected when compared with cases of acute loss. On the other hand, the effects of hearing improvement on localization ability observed in COM patients were smaller than those of simulated acute hearing loss achieved by earplugs in normal subjects. This seems to suggest that the localization cues in patients with chronic hearing loss are different from those under normal conditions.

Transient Hearing Loss and Objective Tinnitus Induced by Mouth Opening: A Rare Connection Between the Temporomandibular Joint and Middle Ear Space.

Objectives: To describe objective tinnitus complicated with transient low-tone hearing loss coinciding with mouth opening, which was related to the connection between the mandibular fossa and middle ear space. Patients: A 41-year-old man presented with tinnitus, ear fullness, and hearing loss in the left ear on mouth opening. Main Outcome Measures: Clinical case records, audiological data, and radiological analyses including computed tomography (CT) and magnetic resonance imaging. Results: Hearing thresholds on the affected side, which were evaluated with mouth opening, showed elevations of approximately 20 dB in the frequencies below 1000 Hz. Again, peak pressure on the tympanogram deviated negatively to −220 mmH2O under mouth opening without changing peak amplitude. CT showed a connection between the mandibular fossa and middle ear space, as revealed by a gas collection around the joint capsule evaluated in two phases (with and without mouth closing). Ear symptoms resolved after myringotomy. Conclusions: Although an influence of temporomandibular disorder (TMD) on tinnitus perception has been debated, whether this association is causal or fortuitous has remained contentious. The present case showed a unique feature of tinnitus attributed to a connection between the mandibular fossa and middle ear space.

DEVELOPMENT OF AN APPARATUS FOR DIAGNOSIS OF OSSICULAR CHAIN MOBILITY

Confumation of the conditions of the ossicles is essential for tympanoplasty. Although several methods to measure ossicular mobility have been reported, the quantitative evaluation of ossicular mobility has been difficult to date. We have therefore developed a new system with which it is possible to quantitatively evaluate ossicular mobility during surgery. The apparatus enables us to simultaneously obtain the reaction force from the ossicles and its displacement, Force-displacement curves obtained from otosclerotic ears were clearly different from these obtained from normal subjects. Furthermore, preand post-treatment results showed significant differences. With this new apparatus, it is possible to distinguish the differences in mobility of the ossicles between normal and fixed ossicles, as well as estimate the change of the mobility between preand post-treatment for ossicular futation.

Development of an Apparatus for Diagnosis of Ossicular Chain Mobility in Humans

Confirmation of the conditions of the ossicles is essential for tympanoplasty. However, at present, ossicular mobility is experimentally estimated with palpation by a surgeon, and the results depend on the surgeons skill. In this study, a new apparatus for quantitatively measuring ossicular mobility was developed. With this apparatus, the ossicles were displaced and the reaction force from the ossicles, (i.e. the load applied to the ossicles) was simultaneously detected. Ossicular mobility of three patients with otosclerosis or chronic otitis media was measured to evaluate the usability of the apparatus. The apparatus can distinguish the differences in ossicular mobility between normal and fixed ossicles, and it makes estimating the change of mobility between pre- and posttreatments for ossicular fixation possible. Positive correlation was seen between ossicular mobility and hearing level.