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Dive into the research topics where Koji Tokumasu is active.

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Featured researches published by Koji Tokumasu.


Laryngoscope | 2006

Water May Cure Patients With Meniere Disease

Hideaki Naganuma; Katsumasa Kawahara; Koji Tokumasu; Makito Okamoto

Objectives/Hypothesis: We examined whether sufficient water intake is effective in the long‐term control of vertigo and hearing activity in patients with Meniere disease (MD) for whom conventional therapy has proven unsuccessful.


Acta Oto-laryngologica | 1996

Initial Symptoms and Retrospective Evaluation of Prognosis in Meniere's Disease

Koji Tokumasu; Akito Fujino; Hideaki Naganuma; Isao Hoshino; Motohiro Arai

Clinical studies on an initial symptom and a long-term course of vertigo and hearing impairment and retrospective evaluation of the prognosis were performed in Menières disease. One hundred and fifty-one patients (67 males and 84 females) with Menieres disease were treated in the Neuro-otological clinic, Kitasato University Hospital from 1990 to 1995. Ages ranged from 17 to 77 years (mean 47.3 years) at the onset of the disease when the first vertigo attack occurred. There were 106 (70.1%) in their 30s, 40s and 50s, and 28 (18.5%) aged 60 years or over. Seventy-eight patients visited the clinic within one year of the onset of the disease, but the mean interval was 4 years and 5 months (the longest was 25 years). The mean duration time for the follow-up studies from the time of their first visit to the hospital was 2 years and 5 months. The bilateral ears were invaded in 19 patients (12.6%) and the mean length of their time course was 9 years and 10 months which is longer than the length in unilateral cases. Several important key points for diagnosis of Menières disease were investigated in 28 of the 151 cases who had been followed up successfully over a relatively long time course (the mean follow-up time was 7 years and 3 months). Fluctuated or stational cochlear signs, such as tinnitus, hearing impairment and/or fullness in the ear, had started prior to the onset of the first vertigo attack in 17 (61%) of 28 cases. Vertigo without cochlear sign appearing at the onset and cochlear signs were combined later in six (21%) of the 28 cases. Only five (18%) of the 28 cases had vertigo combined with a cochlear sign simultaneously at the onset of the disease. The affected ear was on the left in 15 cases and on the right in seven of 22 unilateral cases. In six bilateral cases the left ear was the first to be invaded in four out of six cases. The interval between the first and second attacks was over 1 year in six of the 28 cases and over 6 months in 10 of the 28 cases. Nine out of the 28 patients had recurrence of vertigo attacks during the first month and five of the nine had a cluster of attacks in the first month. Our study of 28 patients over a long time course revealed eight patients (28.6%) free from the disease. These patients had no recurrence of vertigo for more than 2 years after their last attack, and sixteen (57.1%) of the 28 patients had no recurrence of vertigo for more than 1 year. However, a long period of relief time of more than 2 years in 11 of the 28 patients and a period of more than 1 year was noticed in 16 of the 28 patients. Hearing levels at the middle and low frequencies in the first hearing test were compared with the last test. The mean of hearing levels changed from 38.1 to 36.2 dB after 2 years and 1 month in six cases with the right ear affected and from 34.1 to 45.3 dB after 5 years and 3 months in 15 cases with the left ear affected, but in seven cases with bilateral diseased ears the hearing in both ears became worse, from 25.5 to 57.1 dB in the right ear and from 30.5 to 53.6 dB in the left ear during a period of more than 10 years. These clinical findings should be utilized for diagnosis at the onset of Menières disease to determine the interval for observation in order to evaluate the efficacy of treatment.


Annals of Otology, Rhinology, and Laryngology | 2001

Three-Dimensional Analysis of Morphological Aspects of the Human Saccular Macula

Hideaki Naganuma; Koji Tokumasu; Shinichiro Hashimoto; Makito Okamoto; Shohei Yamashina

The 3-dimensional shape of the human saccular macula and its orientation in the skull were quantitated in this study. The semicircular canals and saccular maculae were reconstructed 3-dimensionally on a computer from 3 human temporal bones. The 380 to 522 triangles in the entire area of the saccular macula were made by drawing lines between 2 adjacent points every 100-μm width of the saccular macula in each section. The angles between each triangle and each estimated standard axis in the skull obtained were calculated. This information will provide standard data regarding the 3-dimensional morphological aspects of the saccular macula for further investigations of the function of the sacculus. It was determined that the 3-dimensional shape of the saccular macula was not a plane, but was a curved surface like that of an ellipsoid. It is thought that this shape is necessary in order for the saccular macula to detect wide-range linear acceleration.


Acta Oto-laryngologica | 1996

Basophilic Deposits on the Cupula: Preliminary Findings Describing the Problems Involved in Studies Regarding the Incidence of Basophilic Deposits on the Cupula

Hideaki Naganuma; Robert I. Kohut; Jai H. Ryu; Koji Tokumasu; Makito Okamoto; Akito Fujino; Isao Hoshino; Motohiro Arai

In this study, the possibility of whether basophilic deposits adhered to the cupulas in the semicircular canals was investigated histologically. Results indicated that basophilic deposits were present in all three cupulas of the semicircular canals. The overall incidence of basophilic deposits in the superior, lateral and posterior semicircular canal cupulas was 26%, 41% and 37%, respectively. The incidence of basophilic deposits bound to the cupulas increased with age. The possible origin of these basophilic deposits on the cupulas and the increased incidence of basophilic deposits with increasing age are discussed.


Annals of Otology, Rhinology, and Laryngology | 2005

Three-Dimensional Reconstruction of the Human Semicircular Canals and Measurement of Each Membranous Canal Plane Defined by Reid's Stereotactic Coordinates

Shinichiro Hashimoto; Hideaki Naganuma; Koji Tokumasu; Akihiko Itoh; Makito Okamoto

Objectives: Equations for estimating the planar relationships of the human semicircular canals were devised by Blanks et al from a dissected bony labyrinth in a human skull. However, a similar study on the membranous semicircular canal planes has never been published. Methods: In this study, the angle between each membranous canal plane and Reids stereotactic horizontal plane was measured on serial histologic sections of 7 temporal bones from Japanese adults. We reconstructed the 3 semicircular canals by computer-aided 3-dimensional analysis. The angles between each pair of both bony and membranous canal planes were measured. Results: In the bony labyrinth, the angles between the 2 canal planes of the lateral-anterior, anterior-posterior, and lateral-posterior pairs were 90.51° ± 2.98° (mean ± SD), 91.70° ± 1.85°, and 94.52° ± 3.32°, respectively. The angles between the 2 membranous canal planes of the lateral-anterior, anterior-posterior, and lateral-posterior pairs were 90.05° ± 4.74°, 91.03° ± 2.93°, and 91.92° ± 5.22°, respectively. Conclusions: The data from our study of the membranous labyrinth showed that the angles between each canal plane and the others were much closer to 90° than was found by Blanks et al for the bony labyrinth.


Acta Oto-laryngologica | 1995

Prognosis of Meniere's Disease by Conservative Treatment: Retrospective Study on the Time Course of the Disease

Koji Tokumasu; Akito Fujino; Satoshi Yoshio; Isao Hoshino

The incidence of Menières disease was investigated in a total of 3222 patients with vertigo or dizziness who had visited Kitasato University Hospital during 1985-1991. Two hundred and fifty-one of the cases (7.8%) were found to suffer from Menières disease and the male:female ratio was 1:1. Seventy cases of Menières disease with complete records were classified into five groups, depending on the duration of the illness since its onset. Both ears were affected in 12 (17.1%) of the patients but in 4 (33.3%) of prolonged 12 patients having more than 15 years after the onset. All 70 patients had been treated conservatively, except for 3 who had undergone surgery. Frequency of vertiginous attacks and hearing impairment during the last year in each group were retrospectively compared with those of the other groups. No vertiginous attacks were experienced in 13 (24.1%) cases. The average number of vertigo attacks during the last year was 4.5 per year in 49 cases. Adequate therapy is desirable within one year after the onset of Menières disease: the results showed the frequency of vertiginous attacks to be lowest and hearing levels to be best in the first group who were treated less than one year after the onset, in comparison with the other prolonged cases.


Auris Nasus Larynx | 1993

A case of cavernous hemangioma in the internal auditory canal.

Akito Fujino; Koji Tokumasu; Satoshi Yoshio; Yasuhiro Momiyama; Meijin Nakayama

A case of cavernous hemangioma in the internal auditory canal was reported. The chronology of this case was similar as one of Ménières disease. The neurotological findings in this case were no specific findings to differentiate cavernous hemangioma from acoustic neurinoma. The high-resolution computed tomography (HRCT) revealed calcium stippling in the lesions, whereas magnetic resonance imaging (MRI) demonstrated a low signal intensity on both T1- and T2-weighted images. Comparison of HRCT and MRI findings is most useful for differential diagnosis of intracanalicular tumors.


Acta Oto-laryngologica | 1993

Prolonged Dysequilibrium in Three Cases with Vestibular Neuronitis: Efficacy of Vestibular Rehabilitation

Koji Tokumasu; Akito Fujino; Hiroo Noguchi

The clinical course of acute unilateral vestibular disturbance in 3 cases with vestibular neuronitis and a case with labyrinthine destruction was surveyed for a long-term period. Vestibular training with a modified Cawthorne-Cookseys exercise was done in 2 of 3 cases with vestibular neuronitis and a case of labyrinthine destruction. All had no severe troubles in activities of their daily lives over one year after the onset of the disease, but the central compensation was not completed, even in a young patient, in a case of labyrinthine destruction and in a well trained case. Spontaneous nystagmus to the affected side and increase of body sway with eyes closed were revealed by examinations in all cases. Physical exercise was found to be effective for relief from vestibular ataxia, but it was difficult to keep the effect even after training.


Acta Oto-laryngologica | 1995

Preliminary Guidelines for Reporting Treatment Results in Meniere's Disease Conducted by The Committee of the Japanese Society for Equilibrium Research, 1993

Kanemasa Mizukoshi; Yukio Watanabe; Hideo Shojaku; Takashi Matsunaga; Koji Tokumasu

In order to draft guidelines for reporting treatment results in Menières disease (MD) in Japan, 17 committee members elected from the Japanese Society for Equilibrium Research (JSER) have met for about two years. The preliminary guidelines obtained from their discussions are summarized as follows. i) Evaluations of symptoms: Only definitive vertiginous spells with spontaneous nystagmus should be evaluated (AAOO, 1972). The parameter for the assessment of hearing levels should be evaluated using four-frequency pure-tone averages (PTA) at 250 Hz, 500 Hz, 1 kHz and 2 kHz. ii) Evaluation period: Valid results for the evaluation should be based on observations at least six months before treatment and over at least 12 months after initiation of therapy. iii) Evaluation criteria The formula expressing the effects of treatment on vertiginous spells should adopt a numeric vertigo score, which is shown in the AAO-HNS (1985) guidelines. If the duration of pre-treatment evaluation period is less than 6 months, the divisor is replaced by the average of definitive spells per month for the period of observation. iv) Global judgment: For a global judgment, patients and doctors should jointly evaluate the treatment results from the standpoints of their subjective and objective symptoms respectively.


Acta Oto-laryngologica | 1996

Vestibular Training for Acute Unilateral Vestibular Disturbances: Its Efficacy in Comparison with Antivertigo Drug

Akito Fujino; Koji Tokumasu; Makito Okamoto; Hideaki Naganuma; Isao Hoshino; Motohiro Arai; Satosi Yoneda

We carried out a clinical trial on the treatment of acute unilateral vestibular disturbances (AUVD) without typical Menieres disease and benign paroxysmal positional vertigo. Two therapy groups were selected: vestibular training (VT) with drug therapy and drug administration alone. After the experimental period of 8 weeks, all patients were classified into two groups depending on the methods of treatment, and the clinical courses of the patients were compared statistically. It was confirmed statistically by global judgments of symptoms and signs that improvement rates were higher in the group treated by VT with medication than the improvement rate in the group with medication alone. It is concluded that VT is effective for early relief from vestibular ataxia.

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