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Dive into the research topics where Kiyotaka Murata is active.

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Featured researches published by Kiyotaka Murata.


Otolaryngology-Head and Neck Surgery | 1996

An objective evaluation method for facial mimic motion

M. Isono; Kiyotaka Murata; H. Tanaka; M. Kawamoto; H. Azuma

This technique was designed to establish a simple, objective evaluation system for facial paralysis through the use of a personal computer. A total of 24 marks were placed on the faces of subjects for the following procedures. Movements of the face were photographed with a video-camera and fed continuously into the computer. Ten frames per movement representing facial movement from rest to maximum movement were selected for analysis. By means of a digital image-processing technique, only the marks placed on the face were extracted, and the movement of these marks was quantitatively analyzed. A total of 44 healthy subjects with no history of facial paralysis were used as a normal control group. The patients with facial paralysis consisted of nine subjects with Bells palsy and three with Ramsay Hunt syndrome. In the eye-closing motions, no significant differences were found between the sum of the movement distances on the left and right sides in each normal subject. However, the patients with facial paralysis showed distinct differences from those obtained in the normal subjects. The improvement process was also evaluated with a ratio of affected- and normal-side facial movements.


Auris Nasus Larynx | 1999

Computerized assessment of the mastoid air cell system.

Michio Isono; Kiyotaka Murata; Hiroji Azuma; Masahiro Ishikawa; Akihiko Ito

There have been many arguments on the development of pneumatization of temporal bone. However, a technique for direct volume measurement from high resolution computed tomography has never been reported. The aim of this paper is to develop a technique by using digital image processing to measure the volume of the mastoid air cell system. Forty three ears of 26 healthy subjects (13 males and 13 females) without a history of chronic or exudative otitis media, clear signs of Menieres disease, severe sensorineural hearing impairment or malformation of temporal bone were eligible for enrolment in this study. Using a digital image processing technique, only the black air cells and tympanic cavity on the CT films are easily selected. Then, after image processing, only areas of these extracted black pneumatized parts are calculated. Consequently, the volume of pneumatized parts of temporal bone could be calculated separately as total volume and as partial volume that divided by several CT planes. The average volume of pneumatization in 43 temporal bones was 5.97 ml. However, since the volume of pneumatization in the temporal bone has traditionally been estimated by analyzing areas on X-ray films, the new method described in this study is significant for its ability to directly measure the volume of pneumatization in the temporal bone.


International Journal of Pediatric Otorhinolaryngology | 1997

Minute findings of inner ear anomalies by three-dimensional CT scanning

Michio Isono; Kiyotaka Murata; Kazuko Aiba; Hiroaki Miyashita; Hisaya Tanaka; Masahiro Ishikawa

In actual clinical situations, inner ear anomalies must be diagnosed by image diagnosis such as high resolution CT-scanning of the temporal bone before three dimensional (3D) CT-scanning was introduced. In this paper, the usefulness of 3D-CT was investigated in some anomaly cases. It was found that 3D-CT was useful in observing the minute structure of the inner ear in that it could ascertain spatial relationships and minute constrictions and protrusions that could not be detected by 2D analysis. This CT was also capable of assessing the stage of embryological injuries and evaluating anomalies in cochlear turning that are the hidden factors of hearing impairment.


Auris Nasus Larynx | 1994

Tympanoplasty with reconstruction of soft posterior meatal wall in ears with cholesteatoma.

Hiroshi Hosoi; Kiyotaka Murata

A surgical technique for the reconstruction of a posterior meatal wall using a soft material (fascia) was developed for ears with cholesteatoma. Both myringoplasty and reconstruction of the posterior meatal wall were simultaneously performed using a large sheet of fascia, after the removal of the posterior meatal bony wall and the lesion. Even if postoperative middle ear aeration is disturbed, a retraction pocket may be expected to occur easily in ears with a soft posterior meatal wall, because of its flexibility compared to ears with a usual hard posterior meatal wall. This method is simple and can be useful in ears in which the posterior bony wall is removed.


Auris Nasus Larynx | 1995

Study on Cathepsin B Activity in Human Thyroid Tumors

Takeshi Kusunoki; Shozo Nishida; Takayuki Nakano; Kunihiko Funasaka; Saori Kimoto; Kiyotaka Murata; Takanori Tomura

Cathepsin B activity was measured in human thyroid tissue obtained surgically from 2 patients with Graves disease, 3 with follicular adenoma, 4 with papillary carcinoma, and 4 with follicular carcinoma. Three normal thyroid tissues were also studied. Comparisons were made between cathepsin B activity and clinical findings, including histopathological diagnosis and the presence or absence of extra-capsular invasion and metastasis. The abilities of original tumors to degrade type I and type IV collagen were also measured. Mean cathepsin B activities of both specimens with benign and those with malignant disease were significantly higher than those of normal thyroid. On cases of thyroid carcinoma, those with extra-capsular invasions and metastasis had the highest cathepsin B activities. Cases with high cathepsin B activities also tended to show high type I and IV collagen degrading abilities. These findings suggest that cathepsin B plays a role in the development of extra-capsular invasion and lymph node metastasis in human thyroid tumors.


International Journal of Pediatric Otorhinolaryngology | 1999

Suggestion audiometry for non-organic hearing loss (pseudohypoacusis) in children

Hiroshi Hosoi; Yoshiaki Tsuta; Kiyotaka Murata; Harry Levitt

Pertaining to non-organic hearing loss in children, three goals should be attained: detection of this disease, determination of true hearing levels and information about the possible cause. Recently, objective tests have been used principally for children with non-organic hearing loss; however, these lack the simplicity and convenience of traditional audiometry. A new method, which is referred to as suggestion audiometry, since it is suggested to the patient that hearing will be improved as a result of the test procedure, was developed for the purpose of simultaneously achieving the above-stated three goals. The subjects were 20 patients aged 8-16 years suspected of demonstrating non-organic hearing loss and whose apparent hearing loss had been identified by school hearing examinations. Suggestion pure tone audiometry was useful for the detection of non-organic hearing loss and suggestion speech audiometry was valuable for the determination of true hearing levels. The subjects were classified into four groups according to the test results. We discuss causes of the disease based on the classification of the subjects obtained from this test procedure.


Journal of Laryngology and Otology | 1998

Long-term observation after soft posterior meatal wall reconstruction in ears with cholesteatoma

Hiroshi Hosoi; Kiyotaka Murata; Hiroki Kimura; Yoshiaki Tsuta

We performed tympanoplasty with reconstruction of the soft posterior meatal wall for the prevention of post-operative retraction pocket formation. Our method is characterized by the reconstruction of the soft posterior meatal wall, non-obliteration with permanent or temporary materials, including Gelfoam, no use of a Palva flap and the use of fibrin glue for attaching the fascia to the posterior meatal skin. None of the patients experienced post-operative narrow-neck retraction pocket formation, and whenever aeration of the middle ear was disturbed, a balloon-like retraction was observed. Not all the posterior meatal walls retracted. The final position of the posterior meatal wall varied among the subjects. No serious cavity or hearing problems have occurred since surgery. Due to the strong possibility of post-operative retraction pocket formation in cases with a large balloon-like retraction, we rejected adopting the canal wall up technique or hard posterior meatal wall reconstruction.


American Journal of Otolaryngology | 2011

Cochlear changes in presbycusis with tinnitus.

Kyoichi Terao; Sebahattin Cureoglu; Patricia A. Schachern; Norimasa Morita; Shigenobu Nomiya; Armin Farajzadeh Deroee; Katsumi Doi; Kazunori Mori; Kiyotaka Murata; Michael M. Paparella

OBJECTIVES The pathophysiology of tinnitus is obscure and its treatment is therefore elusive. Significant progress in this field can only be achieved by determining the mechanisms of tinnitus generation, and thus, histopathologic findings of the cochlea in presbycusis with tinnitus become crucial. We revealed the histopathologic findings of the cochlea in subjects with presbycusis and tinnitus. MATERIAL AND METHODS The subjects were divided into 2 groups, presbycusis with tinnitus (tinnitus) group and presbycusis without tinnitus (control) group, with each group comprising 8 temporal bones from 8 subjects. We quantitatively analyzed the number of spiral ganglion cells, loss of cochlear inner and outer hair cells, and areas of the stria vascularis and spiral ligament. RESULTS There was a significantly greater loss of outer hair cells in the tinnitus group compared with the control group in the basal and upper middle turns. The stria vascularis was more atrophic in the tinnitus group compared with the control group in the basal turn. CONCLUSIONS Tinnitus is more common in patients with presbycusis who have more severe degeneration of outer hair cells and stria vascularis.


Auris Nasus Larynx | 2002

Histopathological findings of human thyroid tumors and dynamic MRI

Takeshi Kusunoki; Kiyotaka Murata; Shozo Nishida; Takanori Tomura; Masaaki Inoue

OBJECTIVE Time intensity curves for gadolinium-diethylenetriaminepentaceticacid (Gd-DTPA) enhanced magnetic resonance imaging (MRI), namely dynamic MRI, were determined for thyroid diseases, and compared with findings of histopathologic examination. METHODS Time intensity curves for the thyroid tumors were determined. Three different patterns of time intensity curves were observed: a rapid washout pattern, a delayed washout pattern and no change. Cell proliferating activities of thyroid tumors were estimated immunohistochemically by proliferating cell nuclear antigen (PCNA). RESULTS In most of malignant diseases and a few benign diseases that had marked cell proliferative activity with showing more than 20% on labeling indexes of PCNA, the time intensity curve displayed the delayed washout pattern, in which intensity was above half-maximal value within 10 min after injection Gd-DTPA. Almost all benign diseases and a few well differentiated carcinomas displayed the rapid washout pattern, in which intensity was decreased to lower than half of peak grade within 10 min following injection and showed from 10 to 20% on labeling indexes of PCNA. Benign diseases that displayed no change of time intensity curve did not show PCNA positive cells. CONCLUSION These findings suggested that the time intensity curve obtained from dynamic MRI might indicate cell proliferating activity of thyroid tumors.


American Journal of Otolaryngology | 2011

Pathologic correlations of otologic symptoms in acute lymphocytic leukemia

Kyoichi Terao; Sebahattin Cureoglu; Patricia A. Schachern; Michael M. Paparella; Norimasa Morita; Shigenobu Nomiya; Taro Inagaki; Kazunori Mori; Kiyotaka Murata

OBJECTIVES To assess the clinicopathologic correlations of otologic complaints in patients with acute lymphocytic leukemia. DESIGN Otologic complaints and histologic findings were evaluated in 25 temporal bones of 13 acute lymphocytic leukemia patients. RESULTS Nine patients had a history of otologic complaints, including hearing loss, otalgia, otorrhea, and vertigo in 5, 3, 3, and 2 patients, respectively. Hemorrhage was most commonly observed in the middle ear (6 patients, 9 temporal bones) and was also observed in cochlea (4 patients, 4 temporal bones), and vestibule (6 patients, 6 temporal bones). Leukemic infiltration was observed in the petrous apex (13 patients, 24 temporal bones), middle ear (7 patients, 14 temporal bones), cochlea (3 patients, 4 temporal bones), vestibule (3 patients, 4 temporal bones), and internal auditory canal (5 patients, 8 temporal bones). Inflammatory changes were observed in the cochlea (5 patients, 8 temporal bones) and vestibule (5 patients, 8 temporal bones). Middle ear effusion containing floating tumor cells was observed in 4 temporal bones of 3 patients. Irreversible histopathologic changes of the middle ear, such as the destruction of the ossicles, perforation of the tympanic membrane, and granulation tissues were observed in 5 temporal bones of 4 patients. CONCLUSIONS Ear involvement is common in acute lymphocytic leukemia patients. With prolonged survival due to the progress of treatment, the diagnosis and treatment of nonhematopoietic system symptoms, such as ear problems due to acute lymphocytic leukemia, have become more important.

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