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Featured researches published by Akihiko Fujita.


American Journal of Otolaryngology | 1989

Effect of adenoidectomy on otitis media with effusion, tubal function, and sinusitis

Haruo Takahashi; Akihiko Fujita; Iwao Honjo

Three clinical studies were performed to investigate the effects of adenoidectomy on otitis media with effusion (OME), especially with regard to eustachian tube (ET) disfunction and sinusitis, which often accompanies OME. In the first study, the audiograms, tympanograms, and ET ventilatory functions of 78 adenoidectomized patients (121 ears) and 54 non-adenoidectomized patients (63 ears) were compared over 6 months. The audiograms and tympanograms of the adenoidectomized group showed significant improvement; however, no difference in passive tubal opening pressure was noted despite an improvement in positive pressure equalizing function observed in the adenoidectomized group at 6 months after the operation. In the second study, tubal passive resistance (PR) and the ratio of passive resistance to active resistance (PR/AR) were compared before and 1 month after adenoidectomy using the forced response test (12 subjects, 12 ears). Neither PR nor PR/AR had significantly improved after the operation. In the third study, sinusitis improvement in 45 adenoidectomized patients 6 months after the operation was evaluated in comparison with 33 non-adenoidectomized patients. This condition was found to have improved significantly in the adenoidectomized group. Overall, adenoidectomy appeared effective in reducing the incidence of OME and sinusitis, and in improving the active ventilatory function of the ET without causing changes in the tubal passage. It is conceivable that tubal active ventilatory function was improved due to a reduction of inflammation and pollution around the nasopharynx by adenoidectomy, and that the effect of adenoid mass on the ET is minimal.


Laryngoscope | 1994

Eustachian tube compliance in cleft palate a preliminary study

Haruo Takahashi; Iwao Honjo; Akihiko Fujita

With the use of the tubal compliance test and the forced response test (FRT), the compliance and ventilatory functions of the eustachian tube (ET) were examined in 19 children with otitis media with effusion (OME) and cleft palate, in 31 children with OME but without cleft palate, and in 19 individuals with traumatic perforation of the eardrum without history of other otological disease (controls). The tubal compliance results in the group with both cleft palate and OME were significantly higher than the results obtained with the controls, but did not differ significantly from the results obtained with the patients with OME but without cleft palate; this indicated that the ETs of those patients with OME and cleft palate, and the ETs of those patients with OME but without cleft palate, appeared to be more collapsible than the ETs of normal subjects. It was speculated that such an aerodynamic property of the ET observed in the group with OME and cleft palate and in the group with OME but without cleft palate may be due mainly to possible inflammatory condition of the tubal mucosa rather than to abnormal anatomy or to an abnormal physical property of the framework (such as cartilage) of the ET.


European Archives of Oto-rhino-laryngology | 1996

Endoscopic findings at the pharyngeal orifice of the eustachian tube in otitis media with effusion

Haruo Takahashi; Iwao Honjo; Akihiko Fujita

Transnasal endoscopy of the pharyngeal orifice of the eustachian tube was performed on 155 ears with otitis media with effusion (77 ears of children, 78 ears of adults). In children, blockage of the orifice by mucopurulent nasal discharge was the most frequent finding (72.7%), followed by compression of the orifice by the adenoid tissue (52.0%), hypertrophy of the peritubal tonsil (16.9%), and edema around the orifice, especially at its posterior lip (10.4%). In adults, the most frequent abnormal finding was edema of the orifice (26.9%), followed by blockage of the orifice by mucopurulent nasal discharge (23.1 %), and atrophy of the orifice (10.3%). In 39.7% of cases findings were normal. Thus, main pathological findings associated with tubal dysfunction involved inflammation in the nasopharynx.


American Journal of Otolaryngology | 1993

Refractory otitis media with effusion from viewpoints of eustachian tube dysfunction and nasal sinusitis

Akihiko Fujita; Iwao Honjo; Kyosuke Kurata; I-Ken Gan; Haruo Takahashi

INTRODUCTION Most children with otitis media with effusion (OME) recover spontaneously before adolescence. However, some children have refractory OME. This study was undertaken to evaluate eustachian tube function and concurrent upper respiratory tract inflammatory conditions in adolescents with refractory OME. METHODS A group of 83 adolescent patients with refractory OME was identified. Ages range from 10 to 20 years. A control group of 108 children with OME (ages 4 to 9) serve as the basis for comparison. All underwent both passive and active eustachian tube function testing, dye clearance studies, and a sniffing test. Upper respiratory tract inflammation was assessed by roentgenograms of the paranasal sinuses and mucosalivary function. RESULTS High-pressure tubal opening was demonstrated in 31% of patients with refractory OME. In contrast, 84% of children with routine OME had normal opening. A marked disturbance of dye clearance was noted in refractory OME cases. Active tubal function during swallowing was disturbed in both adolescent and childrens OME groups without any significant difference between them. Paranasal sinusitis was identified in 49% of adolescents with refractory OME. In contrast, 78% of children with OME had abnormality of the sinuses. CONCLUSION Approximately one half of adolescents with refractory OME have demonstrable organic abnormality of the eustachian tube. These data suggest tubal dysfunction may be more important in refractory OME than upper respiratory tract inflammation.


American Journal of Otolaryngology | 1987

Site of eustachian tube dysfunction in patients with otitis media with effusion

Haruo Takahashi; Akihiko Fujita; Iwao Honjo

This study was conducted to identify an exact site of ventilatory dysfunction within the eustachian tube among patients with otitis media with effusion (OME). Using 10 adults with OME, a fine polyethylene tube with a small pore at its tip was inserted into the eustachian tube via its pharyngeal orifice. Negative middle ear pressure was applied through a ventilation tube in the eardrum, and the patients were asked to swallow repeatedly at every 5-mm depth of insertion of the polyethylene tube toward the middle ear. Negative middle ear pressure could be equilibrated by swallowing within 10 mm of tube advancement from the pharyngeal orifice of the eustachian tube in seven of ten patients. It was concluded that the site of tubal ventilatory dysfunction is in the distal part of the cartilaginous portion of the eustachian tube in most adult patients with OME.


Acta Oto-laryngologica | 1994

Assessment of the gas exchange function of the middle ear using nitrous oxide. A preliminary study.

Haruo Takahashi; Tadahiko Sugimaru; Iwao Honjo; Yasushi Naito; Akihiko Fujita; Shizue Iwahashi; Hiroshi Toda

A method for assessing the gas exchange through the middle ear (ME) mucosa using nitrous oxide is introduced. Increases in the ME pressure was determined by a tympanogram or a micropressure sensor inserted into the mastoid cavity during ear surgery under general anesthesia using 67% nitrous oxide, 33% oxygen, and sevoflurane on 30 normal ears, 12 ears with otitis media with effusion (OME), and 3 postoperative ears with chronic adhesive otitis media or cholesteatoma. All the 30 normal ears except one showed varying pressure increase, and an inverse correlation was observed between pressure increase and area of mastoid on radiographs. Pressure increase was observed in 6 (50%) ears with OME, and this finding correlated well with the presence or absence of air space in the ME on computed tomography images examined preoperatively, on ears which had ear surgery, the presence or absence of pressure increase correlated with the degree of previous surgical intervention on the mastoid. The rationale and possibility of clinical application of this method is discussed.


Acta Oto-laryngologica | 1988

Etiological role of adenoids upon otitis media with effusion.

Akihiko Fujita; Haruo Takahashi; Iwao Honjo

To clarify the etiological role of adenoids in OME, the effects of adenoidectomy on Eustachian tube function and nasal sinusitis were examined. Adenoids were found to exert no influence upon tubal opening pressure, nor patency of the Eustachian tube in a static condition. Active function of the tube during swallowing, however, was improved significantly by the adenoidectomy. In addition, adenoidectomy improved nasal sinusitis, and in such patients, their active tubal function was satisfactory. From these results, adenoidectomy was considered to cure OME, partly via improvement of the pathological condition of the nasopharynx represented by nasal sinusitis.


Annals of Otology, Rhinology, and Laryngology | 1996

Cause of eustachian tube constriction during swallowing in patients with otitis media with effusion

Haruo Takahashi; Iwao Honjo; Makoto Miura; Akihiko Fujita

In order to clarify the cause of the constriction of the eustachian tube during swallowing that is often seen in patients with otitis media with effusion, video endoscopy of the pharyngeal orifice of the eustachian tube was performed and superimposed with videograms of the tubal airflow and resistance, which were simultaneously examined by the forced response test. In children with otitis media with effusion (17 ears), when the eustachian tube constricted on the videogram on swallowing, the tubal orifice was found to be squeezed between an elevated soft palate and a hypertrophied adenoid (7/17), squeezed between an elevated soft palate and edema of the posterior lip (7/17), or blocked by nasal discharge (5/17). In adults with otitis media with effusion (7 ears), edema of the posterior lip (5/7) was the main cause of the constriction of the tubal orifice during swallowing. Inflammation in the nasopharynx and the pharyngeal portion of the eustachian tube was considered to be closely related to the tubal constriction, which represents a considerable part of the cause of tubal ventilatory dysfunction in otitis media with effusion.


Annals of Otology, Rhinology, and Laryngology | 1992

Clearance function of eustachian tube and negative middle ear pressure.

Haruo Takahashi; Masahiko Hayashi; Iwao Honjo; Akihiko Fujita

Two experimental studies were performed using 18 cats in order to elucidate the mechanism of the long-lasting course of otitis media with effusion. First, the middle ear (ME) pressure was monitored for 2.5 to 7 hours after filling the whole ME space with saline. On average, −150 mm H2O of negative ME pressure was induced in 3.1 hours. Second, the residual volume of saline with antibiotics, which was put into the ME space 2 to 7 days before, was compared between the side on which tubal ventilatory function was abolished (resection of tensor veli palatini muscle and hamulus pterygoideus) and the opposite, control side. The percentage of the residual volume to the original volume put into the ME was significantly higher on the experimental side (Wilcoxons ranking test, t = 27.0, p < .05), and in one ear on the experimental side, the ME pressure showed −150 mm H2O just before the bulla was opened 2 to 7 days later. These results seem to indicate that tubal ciliary clearance function can induce negative ME pressure when there is fluid in the ME, and that the negative ME pressure induced by clearance of the ME fluid may disturb further clearance of the ME fluid. This condition may cause the long-lasting course of otitis media with effusion.


Annals of Otology, Rhinology, and Laryngology | 1991

Middle Ear Pressures of Children with Otitis Media with Effusion

Haruo Takahashi; Iwao Honjo; Akihiko Fujita; Masahiko Hayashi; Kyosuke Kurata

Middle ear (ME) pressures were measured in 30 children with chronic otitis media with effusion (OME) transtubally with the use of a catheter pressure transducer (Mikro-tip, PC-330F). They were found to range from 40 to −185 mm H2O, the average being mildly negative (–54.33 ± 59.04 mm H2O). About two thirds of these children had pulsating changes of ME pressure; the range of the pressure change was between 10 and 50 mm H2O. The ME pressure tended to be lower in ears with serous effusion than in those with mucoid effusion, but there was no significant difference between them.

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Hiroaki Sato

Iwate Medical University

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