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Dive into the research topics where Hisayoshi Ishizaki is active.

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Featured researches published by Hisayoshi Ishizaki.


Acta Oto-laryngologica | 1998

Intratympanic gentamicin in Meniere's disease

Susanna Kaasinen; Ilmari Pyykkö; Hisayoshi Ishizaki; Heikki Aalto

Ninety-three patients with intractable Menieres disease were treated with gentamicin (Garamycin 40 mg/ml) administered in 1 to 4 transtympanic injections. The patients were tested at frequent intervals and followed up for 2 years. Before treatment all subjects experienced moderate or severe handicap caused by Menieres disease. Two years after the treatment, rotatory vertigo was abolished in 81% of subjects, Tumarkin attacks were cured in 60%, and work capacity was severely reduced in 10% and moderately reduced in 17% of subjects. The outcome of the caloric responses did not correlate with the outcome of the treatment. In logistic regression analysis poor outcome of treatment correlated with Tumarkin attacks (odds ratio 5.5), severity of vertigo (odds ratio 3.8) and gait disorders (odds ratio 2.9). The mean hearing level was significantly affected by the treatment (before, 59.1 dB HL; after, 67.9 dB HL). Ten treated ears became deafened. During follow-up 44 subjects were subjected to retreatment, usually after 6 months. Intratympanic gentamicin treatment is a relatively safe and effective way to treat Menieres disease. The authors recommended starting with 2 injections and renewing the injections if relapse occurs.


Otolaryngology-Head and Neck Surgery | 1994

Intratympanic Gentamicin in Bilateral Meniere's Disease

Ilmari Pyykkö; Hisayoshi Ishizaki; Susanna Kaasinen; Heikki Aalto

Treatment of bilateral Menieres disease is a delicate task. Streptomycin has demonstrated its ability to successfully control the vertigo attacks, but in some cases it results in oscillopsia and transforms the periodic attacks to permanent instability. If the site of the active labyrinth can be determined, a more specific treatment can be tried. We have treated 14 patients with intractable bilateral Menieres disease with intratympanic gentamicin (Garamycin, 40 mg/ml) administered initially in either 1, 2, 3, or 4 injections. The patients were tested at frequent intervals and followed up for 2 years. The work capacity, severity of vertigo, and gait difficulties were scored before treatment and during each test occasion. The postural stability was evaluated on a force platform and sway velocity was analyzed. Before treatment, moderate or severe reduction of work capacity was experienced by all of the subjects, which correlated to severity of vertigo and gait problems. Two years after treatment, the vertigo attacks were eliminated in 11 subjects and controlled in three subjects. The work capacity of three subjects was still moderately or severely reduced. This reduction depended on gait disturbance and Tumarkin attacks. The average postural stability returned to pretreatment level 2 years after the treatment was begun. The outcome of the caloric responses did not correlate with the outcome of the treatment. Hearing was not significantly affected by the treatment. Intratympanic gentamicin treatment is a relatively safe and effective way to treat bilateral Menieres disease when the symptoms can be localized to one ear.


Annals of Otology, Rhinology, and Laryngology | 1991

Tullio Phenomenon and Postural Stability: Experimental Study in Normal Subjects and Patients with Vertigo

Hisayoshi Ishizaki; Heikki Aalto; Ilmari Pyykkö; Jukka Starck

The effect of low-frequency sound (LFS) on postural stability was studied in 55 healthy volunteers and in 152 patients with vertigo due to different types of inner ear disease. The sound pressure levels ranged from 130 to 132 dB and were given at frequencies of 25, 50, and 63 Hz. The duration of each stimulation lasted 30 seconds. The postural responses were measured with a force platform. The LFS stimulation improved the postural stability of the healthy subjects through the alerting response. We did not observe any difference in the body sway according to whether the LFS was delivered with monaural or binaural stimulation. Twenty-six percent of the patients with Menieres disease, 40% with chronic otitis media with vertigo, and 26% with vertigo of peripheral origin experienced significant postural instability at least at two of the three test frequencies during stimulation with LFS. The results demonstrate that in subjects with different types of inner ear disease the vestibular system starts to respond to LFS. The activation of vestibulospinal responses by LFS seems to be an expression of the Tullio phenomenon.


Acta Oto-laryngologica | 2001

Cochlear Blood Flow Measurement in Patients with Me´nie`re's Disease and Other Inner Ear Disorders

Ziane Selmani; Ilmari Pyykkö; Hisayoshi Ishizaki; Timo I. Marttila

To identify an eventual vascular aetiology in different diseases with sensorineural hearing loss (SNHL), the cochlear blood flow (CoBF) was measured using laser Doppler flowmetry (LDF) in 69 patients with Ménières disease (MD), 38 patients with progressive SNHL and 8 patients with sudden deafness. The mean CoBF amplitude at rest was 0.70 mV (SD 0.25) for patients with MD, 0.66 mV (SD 0.21) for patients with SNHL and 0.69 mV (SD 0.23) for those with sudden deafness. No statistically significant difference was observed between the groups with respect to the CoBF amplitudes at rest or during the Valsalva manoeuvre. There was a statistically significant correlation (r = -0.4, p < 0.05) between the hearing level and CoBF amplitude in the SNHL group only. It is concluded that the reduction in vascular flow may not be the main aetiological factor in Ménières disease or sudden deafness. In SNHL the correlation of hearing level with the level of the LDF amplitude can be secondary to the progression of hearing loss.To identify an eventual vascular aetiology in different diseases with sensorineural hearing loss (SNHL), the cochlear blood flow (CoBF) was measured using laser Doppler flowmetry (LDF) in 69 patients with Ménières disease (MD), 38 patients with progressive SNHL and 8 patients with sudden deafness. The mean CoBF amplitude at rest was 0.70 mV (SD 0.25) for patients with MD, 0.66 mV (SD 0.21) for patients with SNHL and 0.69 mV (SD 0.23) for those with sudden deafness. No statistically significant difference was observed between the groups with respect to the CoBF amplitudes at rest or during the Valsalva manoeuvre. There was a statistically significant correlation ( r = -0.4, p < 0.05) between the hearing level and CoBF amplitude in the SNHL group only. It is concluded that the reduction in vascular flow may not be the main aetiological factor in Ménières disease or sudden deafness. In SNHL the correlation of hearing level with the level of the LDF amplitude can be secondary to the progression of hearing loss.


American Journal of Otolaryngology | 1994

Smoking habits and postural stability

Masayuki Iki; Hisayoshi Ishizaki; Heikki Aalto; Jukka Starck; Ilmari Pyykkö

PURPOSE It has been reported that tobacco smoking temporarily affects postural stability We have examined whether smoking habits have a long-term effect on the body balance control using computer-aided posturography. SUBJECTS AND METHODS The postural stability of 80 male forest workers was measured with a force platform technique with eyes closed. Average body sway velocity (ASV [mm/s]) was determined and used as a stability index. Detailed interviews on tobacco smoking and otologic examinations were carried out. Smoking habits were classified into five categories: nonsmokers (53.8%), ex-smokers (17.5%) and current smokers, comprising light (3.8%), moderate (15%), and heavy (10%) smokers. RESULTS The smoking habits of the subjects correlated significantly with ASV, but hours of the exposure to noise and hand-arm vibration from chain saws did not. The correlation of the smoking habits remained significant even after eliminating the effect of age and exposure by partialization. Age in itself had no effect on ASV but interacted with smoking to increase ASV. The group means of ASV increased with the increase in smoking. Significant differences in ASV were found in the moderate and heavy smokers compared with the nonsmokers. CONCLUSION Smokers exhibited more unstable posturographic results than nonsmokers. Smoking habits were suggested to have a long-term effect on the posture control system.


Acta Oto-laryngologica | 1993

Neuroborreliosis in the etiology of vestibular neuronitis

Hisayoshi Ishizaki; Ilmari Pyykkö; Michihiko Nozue

Symptoms and incidence of neuroborreliosis (NB) were studied in ambulatory patients visiting the ENT clinic in Helsinki. Especially we tried to search for possible markers indicating the connection between vestibular neuronitis and NB. A total of 350 patients were screened with the enzyme-linked immunosorbent assay (ELISA) technique for possible antibodies against Borrelia burgdorferi (BB). Twelve patients had positive serological reactions for BB with sera titer levels ranging from 640-14700 (normal < 500). In 2 additional cases, NB was clinically confirmed. In 7 cases a history of tick bite and in 4 cases erythema chronicum migrans was confirmed. In 9 cases, vertigo was the predominant symptom, and in 3 cases the symptoms were linked to facial nerve paresis. Six patients suffered from hearing loss. In 7 cases, the diagnosis was initially settled as vestibular neuronitis. NB seems to be present in about 4% of cases with apparent otologic diseases in Finland. In the majority of the cases, the disease resembles vestibular neuronitis in the acute stage. Since NB is tractable, all patients visiting the ENT clinic, especially those with vertigo, should be screened.


Acta Oto-laryngologica | 1991

Postural Control in Blinds and in Usher's Syndrome

Ilmari Pyykkö; Maarit Vesikivi; Hisayoshi Ishizaki; Måns Magnusson; Martti Juhola

The postural control mechanisms were evaluated in 10 blinds and in 10 subjects with Ushers syndrome. The results were compared with 27 age matched healthy volunteers. In visual conditions the subjects with Ushers syndrome performed worse, but in nonvisual condition they performed equally well as the controls. The results were the same irrespective of whether the tests were performed on a rigid surface or foam rubber covered surface. The blinds and controls performed equally well on the bare surface, but the blinds performed significantly better on the foam rubber covered surface. The results indicate that in subjects with Ushers syndrome the vestibulo-cochlear degeneration is well compensated but the postural stability aggravated due to retinal degeneration. Blind subjects have a better postural control than their seeing referents, but the difference is only evident in situations in which the postural control is hampered by surface perturbation.


Laryngoscope | 2002

Basic Fibroblast Growth Factor in Human Saliva Decreases With Aging

Anders Westermark; Ilmari Pyykkö; Mikael Magnusson; Hisayoshi Ishizaki; Pirkko Jäntti; Gysbert van Setten

Objective Basic fibroblast growth factor (bFGF) has significant properties in wound healing and tissue repair and is suggested to be of importance for the maintenance of mucosal integrity in the upper digestive tract. The purpose of the present study was to identify any age‐dependent variations in the concentration of bFGF in human saliva.


Neurosurgery | 1994

Recovery of the Sutured Facial Nerve after Removal of Acoustic Neuroma in Patients with Neurofibromatosis-2

Göran Blomstedt; Juha Jääskeläinen; Ilmari Pyykkö; Hisayoshi Ishizaki; Henry Troupp; T. Palva

The authors compared the long-term recovery of sutured facial nerves after the removal of 8 neurofibromatosis-2 (NF2)-associated and 22 non-NF2 acoustic neuromas. The patients were from a series of 270 patients operated on for an acoustic neuroma between 1979 and 1989. The assessment was done with a modified House and Brackmann scale from video recordings. At least some facial movement or tone was achieved (Grade 5 or better) in all but three patients, but in none was the recovery excellent. The facial function, judged by the overall appearance in movement, recovered less in patients with NF2 (P = 0.048); a moderately good recovery (Grade 3 or better) was seen in one patient of eight with NF2, as compared with 13 of 22 with non-NF2. In conclusion, if the tumor cannot be peeled off easily from the facial nerve in patients with NF2, leaving a fragment of tumor behind is preferable to cutting and suturing the facial nerve.


Acta Oto-laryngologica | 2002

Use of electrocochleography for assessing endolymphatic hydrops in patients with Lyme disease and Ménière's disease.

Ziane Selmani; Ilmari Pyykkö; Hisayoshi Ishizaki; Nureddin Ashammakhi

From an otological standpoint, Lyme disease can manifest itself as Ménières disease both clinically and electrophysiologically. The aim of this study was to describe the findings of routine clinical, auditory and vestibular tests in patients with Ménières and Lyme disease and to use electrocochleography (ECoG) to assess the presence of endolymphatic hydrops (EH) in both diseases. Transtympanic ECoG was performed in 91 patients with Ménières disease and in 11 patients with confirmed Lyme disease. In both diseases the majority of patients had more than one complaint. There was one case with isolated hearing loss in the Lyme disease group. Typical clinical manifestations of Ménières disease (vertigo, sensorineural hearing loss and tinnitus) were found in 6 11 patients (54.5%) in the Lyme disease group. The ECoG results indicated that there were 65 91 patients (71.4%) with Ménières disease and 5 patients (45.5%) with Lyme disease who presented with EH. No statistically significant difference was found between the incidence of different symptoms of Ménières and Lyme disease. On the basis of these results, patients with Lyme disease should undergo careful examination and investigation, especially in endemic regions. The presence of EH does not exclude the presence of infection with borreliosis as a cause of Ménières disease-like symptoms.

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Heikki Aalto

Helsinki University Central Hospital

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Ziane Selmani

Helsinki University Central Hospital

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H. Aalto

University of Helsinki

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