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Biomedical subjects

I Honjo

Publications and source records attributed to I Honjo.

At least 73 records · Page 4Linked to original sources
PubMed1995

Results with the currently used cochlear implant.

Over the past 7 years we have implanted the Nucleus multichannel cochlear implant in 60 patients with severe hearing impairment. The postoperative speech recognition of adult postlingually deaf patients was satisfactory. Adult prelingually deaf patients exhibited poorer speech perception than postlingually deaf patients. However, some patients showed better results than expected. The prelingually deaf patients needed a longer rehabilitation period than the postlingually deaf patients. There was considerable variation in performance among the prelingually deaf patients. As for juvenile deaf patients, some showed good speech perception ability, but postoperative rehabilitation took longer. The cooperation of doctors, audiologists, speech therapists, schoolteachers, and family members was essential, and the creation of a cochlear implant center for children is desirable to obtain better rehabilitation. On the questionnaire given to the cochlear implant patients, some complained about their hearing in a noisy environment or while listening to television or music. The present cochlear implant system obviously needs further improvement.

Adolescent↗
PubMed1995

Surgical difficulties and postoperative problems associated with cochlear implants.

Since 1987 we have implanted 60 severely hearing-impaired adults with the Nucleus Minisystem-22 cochlear implant. In most cases, the surgical procedures were performed with satisfactory results and very few postoperative problems. The complications associated with cochlear implant surgery include difficulty in drilling the ossified cochlea, electrode displacement, and insufficient insertion of the electrode. Postoperative problems include dizziness, tinnitus, facial nerve spasm, receiver-stimulator migration or extrusion, infection of the scalp flap, and facial nerve palsy. In most cases, these complaints did not develop into serious conditions.

Adult↗
PubMed1995

Cortical activation during sound stimulation in cochlear implant users demonstrated by positron emission tomography.

Three patients with prelingual deafness and six patients with postlingual deafness using multichannel cochlear implants were examined by positron emission tomography using 15O-labeled water. Changes in regional cerebral blood flow (rCBF) were measured during three different sound stimuli: 1) with no sound stimulation, with the speech processor of the cochlear implant system switched off, 2) hearing white noise, and 3) hearing sequential Japanese sentences. In postlingually deaf patients, speech stimulation caused a significantly greater rCBF increase compared with noise stimulation in the left immediate auditory association area and the bilateral auditory association areas. In these patients, speech sound is thought to be processed by means of auditory cortices analogous to those in normal subjects. In contrast, in prelingually deaf patients, speech sound induced much less rCBF increase in auditory association cortices; this finding suggested underdevelopment of the neural network for complex sound analysis and speech sound recognition.

Acoustic Stimulation↗
PubMed1994

Effect of caloric stimulation on primary vestibular fibers originating from otolith organs in the guinea pig.

The influence of caloric stimulation on the primary vestibular fibers originating from the otolith organ was investigated in the guinea pig. Firing rates were recorded from single vestibular neurons in the superior vestibular (Scarpa's) ganglion which were identified physiologically as originating from the otolith organs, mainly from the utricles. Eighty-six percent of the neurons responded to caloric stimulation. Neurons with a high coefficient of variation of firing regularity reacted more sensitively to tilting and also had a tendency to react more sensitively to caloric stimulation. There was a tendency for neurons with increased firing rates in response to ipsilateral tilting to have increased firing rates to warm stimulation, while neurons whose rates increased to contralateral tilting had increased firing rates to cold stimulation. These results indicate that the otolith organs have the same unidirectional tendency to caloric simulation with results comparable to optimal tilting directions.

Action Potentials↗
PubMed1994

Eustachian tube compliance in cleft palate--a preliminary study.

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.

Child↗
PubMed1994

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

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.

Acoustic Impedance Tests↗
PubMed1994

[Cochlear implants in children].

A multichannel cochlear implant was performed in 8 children, and the following results were obtained. The surgical procedures were not as difficult as in adults, and there were few postoperative complications. The results of testing postoperative speech comprehension ability were examined in three children whose course was followed for more than one year postoperatively. Some patients had good speech comprehension ability postoperatively, and we expect to continue performing cochlear implant in children. Postoperative rehabilitation takes longer. The cooperation of physicians, audiologists, speech therapists, school teachers and family members is essential, and establishing a cochlear implant center for children would be desirable.

Adolescent↗
PubMed1994

[Cochlear implants for adult prelingually deaf patients].

We have performed cochlear implants on 6 adult prelingually deaf patients and obtained the following results. 1) The speech comprehension ability of the adult prelingually deaf patients was poorer than in postlingually deaf patients, but some patients showed better results than expected. 2) The adult prelingually deaf patients required a longer period of rehabilitation than the postlingually deaf patients. There were considerable variations in performance among the adult prelingually deaf patients.

Adult↗
PubMed1993

Anticus-lateralis muscle suturing. Treatment of recurrent nerve paralysis.

We have devised a new surgical method that sutures the cricothyroid (anticus) muscle to the paralyzed lateral cricoarytenoid (lateralis) muscle for the dynamic reconstruction of the larynx. Because this method achieved remobilization of the paralyzed vocal cord in dogs, we applied it to seven patients with unilateral recurrent laryngeal nerve paralysis (four patients had postsurgical paralysis and three patients had idiopathic paralysis). We obtained the following satisfactory results: (1) vocal cord tension and voice quality improved in all patients, and (2) in four patients, remobilization of the paralyzed vocal cord was obtained. We believe that this surgical method could serve as a new dynamic method of reconstruction for the treatment of unilateral recurrent laryngeal nerve paralysis.

Anastomosis, Surgical↗
PubMed1993

Remobilization of paralyzed vocal cord by anticus-lateralis muscle suturing.

A new method of dynamic reconstruction by suturing the cricothyroid (anticus) and the lateral cricoarytenoid (lateralis) muscles was devised for the treatment of unilateral recurrent laryngeal nerve paralysis. Eighteen adult dogs underwent this surgical procedure after sectioning a recurrent laryngeal nerve. Immediate postoperative observations revealed a marked increase in tension of the paralyzed vocal cords and remobilization to the median line of 17 of 18 dogs. More than 4 months later, fiberscopic examination revealed a satisfactory adduction of the cords. Electrophysiologic and histologic examination showed reinnervation of the affected lateralis muscle by the external branch of the superior laryngeal nerve. The clinical applications of this surgery may serve as a dynamic reconstruction for unilateral recurrent laryngeal nerve paralysis.

Animals↗
PubMed1993

Fodrin is a constituent of the cortical lattice in outer hair cells of the guinea pig cochlea: immunocytochemical evidence.

Localization of fodrin, a membrane skeletal protein, in the outer hair cell of the guinea pig cochlea was examined by immunocytochemical techniques. By immunofluorescence microscopy, fodrin was observed in the cuticular plate, in the infracuticular network and along the lateral wall. By immunoelectron microscopy of ultrathin cryosections, labeling for fodrin along the lateral wall was localized between the cell membrane and the outermost layer of the subsurface cisternae. Furthermore, pre-embedding immunoelectron microscopy of permeabilized specimens showed that most immunogolds for fodrin were on the thin cross-linking component of the cortical lattice. The results indicate that fodrin is a constituent of the cortical lattice which is thought to play an important role in outer hair cell motility.

Animals↗
PubMed1993

Compliance of the patulous eustachian tube.

The compliance and ventilatory functions of the eustachian tube (ET) of 17 ears with patulous ETs were examined and compared to those of 16 ears with traumatic perforation of the eardrum (controls) by means of the tubal compliance test, the inflation-deflation test, and the forced response test. The tubal compliance was significantly lower in the patulous ETs than in the controls. An excessive patency of the ET was confirmed among the patients with patulous ETs by a low opening pressure during the inflation test and a low passive resistance on the forced response test. Active ventilatory dysfunction was also found to be significantly more common in the patulous ETs by the deflation test and the measure of dilation efficiency. These results indicated that the ET appeared to be rather rigid and less moveable when patulous than when normal.

Adult↗
PubMed1993

Autonomic innervations in the middle ear and pharynx.

Autonomic innervations of the mucosa in the middle ear and pharynx were investigated by retrograde labelling of the autonomic ganglia with horseradish peroxidase (HRP). Of the sympathetic ganglia, the superior cervical ganglion (SCG), middle cervical ganglion (MCG) and stellate ganglion (StG) were examined, and of the parasympathetic ganglia, the pterygopalatine ganglion (PpG) and the otic ganglion (OtG) were examined. Sympathetic innervation of the middle ear mucosa was accomplished by fibers originating in the ipsilateral SCG, but not by those originating in the MSG or StG. Parasympathetic innervation was by fibers originating in the ipsilateral PpG, but not by those originating in the OtG. The epipharynx received sympathetic innervation from the ipsilateral SCG, but not from the MCG or StG. Its parasympathetic innervation was from the PpG bilaterally, but not from the OtG. Sympathetic innervation of the mesopharynx was supplied by the SCG, MCG and StG, but no parasympathetic supply came from the PpG or the OtG. Sympathetic innervation was bilateral, but predominantly from the ipsilateral side. The hypopharynx resembled the mesopharynx, but had more innervation from the MCG and StG.

Animals↗
PubMed1993

Eustachian tube compliance in sniff-induced otitis media with effusion. A preliminary study.

Compliance and ventilatory functions of the eustachian tube (ET) were examined in 20 ears with sniff-induced otitis media with effusion (OME) and 16 ears with traumatic perforation of the eardrum (control) by the forced response test (FRT) including the compliance test, and by the inflation-deflation test. The tubal compliance showed no significant difference between two groups in the FRT. The inflation test revealed that the forced opening pressure was significantly lower in the sniff-induced OME group than in the controls. In the FRT, the active ventilatory dysfunction was also revealed to be significantly more common in the sniff-induced OME. These results suggested that most of the ETs with sniff-induced OME seemed to have excessive patency and poor active opening ability, but may not be hypercompliant or "floppy".

Adolescent↗
PubMed1992

Clearance function of eustachian tube and negative middle ear pressure.

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 (Wilcoxon's ranking test, t = 27.0, p less than .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.

Animals↗
PubMed1992

Pathogenesis of experimental otitis media with effusion caused by a combination of eustachian tube dysfunction and immunosuppression.

Inflammatory factors appear to play an important role in the development of otitis media with effusion (OME). However, otitis media experimentally induced by endotoxin injection or secondary immunoresponse was not persistent. In order to produce refractory OME, two pathologic conditions were necessarily combined: tubal ventilatory dysfunction and suppression of the immunologic defense mechanism by immunosuppressive drugs. In the presence of these two pathologic conditions, all cases that evidenced negative middle ear pressure due to tubal dysfunction developed OME. In the control group with either tubal dysfunction or immunosuppression alone, only 1 of 20 ears developed OME. Transtubal infection due to negative middle ear pressure caused by tubal ventilatory dysfunction may be one of the most important etiologic factors in OME.

Animals↗
PubMed1992

Malignant fibrous histiocytoma of the liver: a case report and review of the literature.

Primary malignant fibrous histiocytoma (MFH) of the liver is reported in a 79-year-old man. The tumor, measuring 8.0 x 8.0 x 6.0 cm, was located in the left lobe of the liver and consisted of spindle cells in a storiform pattern intermingled with bizarre giant cells. Immunohistochemically, most of the tumor cells expressed vimentin. Cytoplasmic immunoreactivity for alpha 1-antichymotrypsin was documented in the giant cells. However, epithelial expression could not be demonstrated.

Aged↗