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Dive into the research topics where Shin-ichi Okumura is active.

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Featured researches published by Shin-ichi Okumura.


Laryngoscope | 2008

Effects of Endolymphatic Sac Drainage With Steroids for Intractable Ménière's Disease: A Long‐Term Follow‐Up and Randomized Controlled Study

Tadashi Kitahara; Takeshi Kubo; Shin-ichi Okumura; Masaaki Kitahara

Objective: Ménières disease is a common inner ear disease with an incidence of 15 to 50 per 100,000 population. Since Ménières disease is thought to be triggered by an immune insult to the inner ear, we examined intraendolymphatic sac application of steroids as a new therapeutic strategy for intractable Ménières disease.


Acta Oto-laryngologica | 1993

Hearing Recovery in Sudden Deafness Patients Using a Modified Defibrinogenation Therapy

Takayuki Shiraishi; Takeshi Kubo; Shin-ichi Okumura; Hiromi Naramura; Masato Nishimura; Masako Okusa; Toru Matsunaga

Ninety-eight patients with idiopathic sudden deafness were treated with a modified defibrinogenation (DF) therapy including batroxobin, low molecular dextran, vasodilators and vitamins. Hearing improvement was evaluated with two methods: categorical judgement and improvement rate (%). By categorical judgement, 60 patients (61% of the total) were classified into recovery or good improvement categories. The improvement rate was calculated for each of the 93 patients, and the average value was 64%. Modified DF therapy was effective especially for patients with severe hearing loss of 70-90 dB with flat audiogram. Although serum fibrinogen significantly decreased after batroxobin administration there was no correlation between the concentration of fibrinogen and hearing recovery. When prognostic factors were studied, the interval between the onset of hearing loss and start of treatment, initial hearing level, and the existence of vertigo all had significant correlation with the degree of hearing recovery.


Neurological Research | 2003

Steroid effects on vestibular compensation in human

Tadashi Kitahara; Kazumasa Kondoh; Tetsuo Morihana; Shin-ichi Okumura; Arata Horii; Noriaki Takeda; Takeshi Kubo

Abstract Vestibular neuritis (VN) rapidly damages unilateral vestibular periphery, inducing severe balance disorders. In most cases, such vestibular imbalance is gradually restored to within the normal level after clinical therapies. This successive clinical recovery occurs due to regeneration of vestibular periphery and/or accomplishment of central vestibular compensation. We experienced 36 patients with VN treated at our hospital, including cases in our previous preliminary report. To elucidate effects of steroid therapy both on the recovery of peripheral function and on the adaptation of central vestibular compensation, we examined caloric test and several questionnaires with two randomly divided groups, 18 steroid-treated and 18 nonsteroid-treated patients, over two years after the onset. These examinations revealed that steroid-treated patients had a tendency of better canal improvements (13/18, 72%) than nonsteroid-treated ones (10/18, 55.6%). However, there was no significant difference between these two groups. In cases with persistent canal paresis, steroid-treated patients (n = 5) reduced handicaps in their everyday life due to the dizziness induced by head and/or body movements and the disturbance of their mood, more effectively than those with nonsteroid therapy (n = 8). These findings suggest that steroid therapy with VN could be effective on not only vestibular periphery but central vestibular system, to restore the balance.


Annals of Otology, Rhinology, and Laryngology | 2001

Effects of Exposing the Opened Endolymphatic Sac to Large Doses of Steroids to Treat Intractable Meniere's Disease

Tadashi Kitahara; Noriaki Takeda; Yasuo Mishiro; Takanori Saika; Munehisa Fukushima; Shin-ichi Okumura; Takeshi Kubo

To enhance the effect of treatment for intractable Menieres disease, we exposed the opened endolymphatic sac to high concentrations of steroids. This technique — endolymphatic sac drainage and steroid instillation surgery — involves the application of a mass of prednisolone followed by absorbable gelatin sponges soaked in a high concentration of dexamethasone into a sac lumen opened and expanded with a bundle of absorbable gelatin film. These sponges are also placed around the sac and coated with biochemical adhesive so that the medicine is slowly delivered into the sac over a prolonged period of time by means of a natural sustained-release vehicle. The short-term results (6 to 14 months) in 12 patients with Menieres disease, including those in stage IV, treated by the above techniques showed that definitive spells were completely controlled in all cases. Hearing was improved, and annoyance due to tinnitus was decreased in all cases except one.


Acta Oto-laryngologica | 2009

Tinnitus as a prognostic factor of sudden deafness

Noriko Hikita-Watanabe; Tadashi Kitahara; Arata Horii; Takayuki Kawashima; Katsumi Doi; Shin-ichi Okumura

Conclusions. The ‘tinnitus-rare’ group had a poorer prognosis for hearing than the ‘tinnitus-often’ group in all sudden sensorineural hearing loss (SSNHL), although the ‘shorter duration’ group had better prognosis than the ‘longer duration’ when restricted to SSNHL accompanied by tinnitus. This indicates that tinnitus itself may not be a sign for poor hearing prognosis but might be an essential sound for the initiation of repair of a damaged auditory system. Objectives. We examined the hearing improvement rate (HIR) and tinnitus at the onset of SSNHL to elucidate the prognostic value of tinnitus accompanying SSNHL. Patients and methods. Fifty patients with SSNHL were treated with systemic administration of steroids. Hearing recovery was determined by comparing the hearing levels before and after treatment. Tinnitus was subjectively evaluated by the tinnitus scoring questionnaire. The score for the five-step evaluation of the subjective tinnitus feelings ‘loudness’, ‘duration’ and ‘annoyance’ was obtained at the onset. Results. In terms of ‘duration’, when we divided all the cases into ‘tinnitus-rare’ group and ‘tinnitus-often’ group, HIR in the ‘tinnitus-rare’ group was significantly lower than that in ‘tinnitus-often’ group. When restricted to the ‘tinnitus-often’ group, HIR for ‘shorter duration’ was significantly higher than that for ‘longer duration’.


Otology & Neurotology | 2008

The Investigation of the Recurrence Rate of Cholesteatoma Using Kaplan-meier Survival Analysis

Yasuo Mishiro; Masafumi Sakagami; Tadashi Kitahara; Kazumasa Kondoh; Shin-ichi Okumura

Objectives: To investigate the recurrence rate of cholesteatoma using Kaplan-Meier survival analysis. Study Design: Retrospective study. Setting: Tertiary referral center. Patients: Three hundred forty-five patients with middle ear cholesteatoma operated on by the same surgeon between 1987 and 2002. Methods: The cumulative recurrence rate of cholesteatoma during a 5-year follow-up period was calculated using Kaplan-Meier survival analysis. Results: The overall 5-year recurrence rate was 11.8%. The recurrence rate increased with the follow-up time. The 5-year recurrence rate was 3.9% in patients treated with canal wall down tympanoplasty (CWDT) and 16.7% in patients treated with intact canal wall tympanoplasty (ICWT) or canal wall reconstruction (CWR) after CWDT with a significant difference (p < 0.01). The 5-year recurrence rate was 26.0% in patients operated on between 1987 and 1996 and 0.7% in patients operated on between 1997 and 2002, again with a significant difference (p < 0.001). Conclusion: Kaplan-Meier survival analysis should be used for calculating the recurrence rate of cholesteatoma. Although this analytic method further demonstrates that CWDT is a more reliable surgical method than ICWT/CWR in reducing cholesteatoma recurrence, clinical judgment should be exercised, and we continue to recommend that a flexible approach should be adopted in deciding whether to perform CWDT or ICWT/CWR for individual cases.


Auris Nasus Larynx | 2000

Postoperative results for cholesteatoma in children

Yasuo Mishiro; Masafumi Sakagami; Shin-ichi Okumura; Noriaki Takeda; Takeshi Kubo

OBJECTIVES to review the postoperative results for cholesteatoma in children. MATERIALS 32 ears with acquired cholesteatoma in children operated on by a single surgeon between 1987 and 1995 and followed up more than 2 years. The mean follow-up period was 5.4 years. RESULTS a one-stage operation was performed in seven ears (21.9%) and preplanned stage operation in 25 ears (78.1%). In the first operation, closed tympanoplasty was performed in 31 ears (96.9%) and open tymapanoplasty in one ear (3.1%). During the second stage operation, residual cholesteatoma was found in 16 ears (64.0%). Recurrent cholesteatoma was detected in 19.4% of ears treated with closed tympanoplasty. The mean postoperative air conduction hearing level was within 20 dB in 12.5%, 30 dB in 40.6% and 40 dB in 78.1%. The hearing results of type III tympanoplasty was better than those of type IV tympanoplasty. CONCLUSIONS preplanned stage tympanoplasty is safer because of the high risk of recurrent and residual cholesteatoma. Surgical methods should be selected flexibly in individual cases depending upon cavity size, eustachian tube function and hearing level. Cholesteatoma in children should be operated on while stapes is present.


Annals of Otology, Rhinology, and Laryngology | 2004

Surgical Management of Special Cases of Intractable Meniere's Disease: Unilateral Cases with Intact Canals and Bilateral Cases

Tadashi Kitahara; Shin-ichi Okumura; Kazumasa Kondoh; Yasuo Mishiro; Tetsuo Morihana; Takeshi Kubo

If a clinician seeks to allow patients with vertigo to return to work as soon as possible, it is very important to determine the appearance of vestibular symptoms during convalescence just after treatment, as well as the long-term results. Apprehensive patients with vertigo may undergo severe psychological torment if treatment requires long-term rest in bed before they can return to daily life. In this paper, we observed postoperative vestibular symptoms (subjective sensation and objective nystagmus) in 50 patients with intractable Menieres disease, including cases from our previous preliminary report, during the period of convalescence just after endolymphatic sac drainage and steroid instillation surgery (EDSS). All symptoms were eliminated within 8 days after EDSS. There was no significant difference in the duration of any vestibular symptoms between bilateral (n = 8) and unilateral cases (n = 42). This result indicates that EDSS could be as safe a treatment for bilateral Menieres disease as for unilateral disease. In unilateral cases with intact semicircular canal function (n = 17), postoperative evoked vestibular sensation, positional, and positioning (Dix-Hallpike) nystagmus disappeared significantly earlier than in those with canal paresis (n = 25). This result indicates that EDSS could keep the vestibular peripheral function of patients with unilateral Menieres disease with intact canals quite stable after surgery. Therefore, EDSS could be recommended as an initial, less-invasive surgical treatment for intractable Menieres disease, especially in unilateral cases with intact canals and in bilateral cases.


Annals of Otology, Rhinology, and Laryngology | 2005

Prognosis of inner ear periphery and central vestibular plasticity in sudden deafness with vertigo

Tadashi Kitahara; Noriaki Takeda; Suetaka Nishiike; Shin-ichi Okumura; Takeshi Kubo

Objectives: We sought to elucidate the clinical problems and otopathology of patients with sudden deafness with vertigo (SDV). Methods: In 24 patients with SDV who had significant canal paresis (CP) at their first visit to our hospital between 1997 and 2001, we examined pure tone audiograms, caloric tests, and several questionnaires twice, at the first visit within 5 days after the onset and around 2 years after steroid therapy. Results: These examinations revealed that improvements of auditory and vestibular function in patients with SDV tended to be correlated with one another. Sixteen of the 24 patients (66.7%) still had CP. This rate in SDV was significantly worse than that reported previously for vestibular neuritis (VN). On the other hand, patients with SDV with long-lasting CP had a faster reduction of head-shaking afternystagmus and of handicaps in their everyday life due to dizziness than did patients with VN and CP. Conclusions: These findings suggest that SDV may deteriorate the inner ear function more severely but accelerate the central vestibular compensation more effectively than VN after the lesion. It is well known that vestibular neurectomy causes much more severe motion-induced dizziness after surgery than does labyrinthectomy. Taken together, these findings suggest different regions of damage in SDV (mainly the labyrinth, as in labyrinthectomy) and VN (mainly the ganglion, as in vestibular neurectomy).


Annals of Otology, Rhinology, and Laryngology | 2004

Management of Hemorrhagic High Jugular Bulb with Adhesive Otitis Media in an Only Hearing Ear: Transcatheter Endovascular Embolization Using Detachable Coils

Kazumasa Kondoh; Tadashi Kitahara; Shin-ichi Okumura; Yasuo Mishiro; Takeshi Kubo

A 51-year-old woman had a hemorrhagic high jugular bulb protruding into the posterosuperior part of the tympanic cavity in her left ear. This (only hearing) ear had severe adhesive otitis media resulting in repetitive hemorrhage from the jugular bulb. Therefore, treatment to stop the bleeding was required. Since invasive middle ear surgery in an only hearing ear would involve a high risk of hearing loss and massive bleeding, transcatheter endovascular embolization using detachable coils was selected for this special case; it safely blocked the blood flow and preserved the patients hearing level. This is the first such report in the otosurgical field, showing that transcatheter endovascular embolization using detachable coils was quite effective in a difficult case of a hemorrhagic high jugular bulb with severe adhesive otitis media in an only hearing ear.

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Yasuo Mishiro

Hyogo College of Medicine

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