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- 咀嚼筋 31P-MRS CSI ^1H-MRS 頭頸部癌 スペクトロスコピー inastication fMRI masseter muscle lactate 頭頸部腫瘍 31P human エネルギー代謝 ^<31>P-CSI functional MRI MRS 顎関節症 筋エネルギー代謝 組織血流量 咬筋 ^<31>P-MRS 咀嚼筋筋電図 咀嚼筋拘縮 咬合感覚異常症 マイオモニター 筋疼痛 筋疲労 咬合異常感 歯根膜 画像診断 image diagnosis
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- 竹内 明子, 箕輪 和行臨床画像 (株)メジカルビュー社 34 (7) 867 - 878 0911-1069 2018/07
- MINOWA KazuyukiGakukansetsu Kenkyukaishi The Japanese Society for Temporomandibular Joint 21 (1) 40 - 45 0915-3004 2009/04/20
- T Sawamura, K Minowa, M NakamuraEUROPEAN JOURNAL OF RADIOLOGY 47 (3) 221 - 226 0720-048X 2003/09 [Refereed][Not invited]
Objective: To compare the shapes of roots of impacted teeth shown in three-dimensional computed tomographic images (3D Dental-computed tomography (CT) images) and plain radiographs and to determine whether 3D Dental-CT images are useful for examination before performing an operation for extraction of a maxillary impacted tooth. Methods and patients: Images obtained from patients who had impacted teeth in the maxilla, including impacted mesial supernumerary teeth in 13 patients, impacted incisors in two patients, impacted canines in 11 patients, impacted premolars in four patients and impacted molars in three patients, were used in this study. In all patients, plain radiographs and 3D Dental-CT images were retrospectively reviewed by an oral radiologist for evidence of root dilaceration before operations to extract the impacted teeth were performed. The findings in the images were compared with intraoperative findings in all cases. Results: The mean specificity and sensitivity of plain radiographs were 95 and 8% respectively, while those of 3D Dental-CT images were 100 and 77%, respectively. There was a statistically significant (P < 0.01) difference between the depiction capabilities of plain radiographs and 3 D Dental-CT images with regard to dilacerations of roots of impacted teeth. Discussion and conclusion: CT may enable radiologists to make a quick and accurate diagnosis of tooth impaction. 3D Dental-CT images are useful for determining the root shape of an impacted tooth in the maxilla. (C) 2002 Elsevier Science Ireland Ltd. All rights reserved. - T Yamaguchi, K Satoh, K Komatsu, N Inoue, K Minowa, Y TotsukaCRANIO-THE JOURNAL OF CRANIOMANDIBULAR PRACTICE 20 (1) 48 - 54 0886-9634 2002/01 [Refereed][Not invited]
Contracture of the jaw-closing muscles is one of the causes of limitation of jaw opening. This study examined whether there is any difference between the EMG activities of jaw-closing muscles during jaw opening in healthy people and in patients with masseter muscle contracture (MMC), who do not have a history of trauma or infection. The patient group consisted of eleven females, 18 to 62 years old with no history of trauma or infections, with limited mouth opening due to MMC. The control group included eleven healthy females, 23 to 50 years old. The EMG activity was recorded bilaterally in the central portion of masseter muscles (Mm), the anterior portion of temporal muscles (Tm), and the anterior belly of digastric muscles (Dm). Nine out of the patient group showed obvious EMG activity in Mm during jaw opening which was different from typical EMG patterns during jaw opening of up to 40 mm in the control group. Among the nine patients, eight showed antagonistic contraction in Tm as well as Mm. The mean integral value of Mm and Tm during jaw opening in the patient group was significantly higher than in the control group (P<0.01). These results suggest that EMG activity during jaw opening in MMC patients with no history of trauma or infections is different from that in healthy people.
MISC
- 歯根膜への機械的刺激時の脳律動変調佐藤 華織, 山口 泰彦, 前田 正名, 齋藤 大嗣, 佐久間 俊光, 箕輪 和行, 横澤 宏一, 下條 暁司, 前澤 仁志 日本顎関節学会雑誌 28- (Suppl.) 126 -126 2016/07
- CT検査と口腔内超音波検査による口腔腫瘍の原発部位診断志摩 朋香, 佐藤 隆文, 入澤 明子, 鈴鹿 正顕, 山野 茂, 西田 睦, 箕輪 和行 超音波医学 42- (1) 91 -91 2015/01
- K Minowa, N Inoue, T Sawamura, A Matsuda, Y Totsuka, M Nakamura DENTOMAXILLOFACIAL RADIOLOGY 32- (1) 2 -7 2003/01 [Not refereed][Not invited]
Objectives: To determine by CT and MRI the contents of static bone cavities (SBCs), which are thought to be formed by aberration of the submandibular gland. Methods: Non-contrast-enhanced and contrast-enhanced CT was performed on 12 subjects (10 male and 2 female; age 18-64 years; mean age 57 years) in whom SBCs had been discovered incidentally on panoramic radiographs during routine dental treatment. MRI was also performed on 3 of the 12 subjects. Results: No submandibular gland tissue was seen in the SBCs in any of the cases. However, fatty tissue of low attenuation was found in the SBCs in all cases on CT images. Blood vessels were seen in the SBCs in 10 cases, and enhanced soft tissue in contact with the bone cavity wall was seen in the SBCs in 2 cases. Blood vessels in the SBCs were observed on MR images in all three cases. Dilatation of the cavity blood vessels was seen in all 10 cases. Slight tortuosity of the blood vessels was seen in 4 of the 10 cases. Conclusions: Examination of contrast-enhanced CT images and MR images revealed that the contents of SBCs were not aberrations of the submandibular gland, as has generally been thought, but fatty tissue, blood vessels and soft tissue. - K Minowa, N Inoue, T Sawamura, A Matsuda, Y Totsuka, M Nakamura DENTOMAXILLOFACIAL RADIOLOGY 32- (1) 2 -7 2003/01 [Not refereed][Not invited]
Objectives: To determine by CT and MRI the contents of static bone cavities (SBCs), which are thought to be formed by aberration of the submandibular gland. Methods: Non-contrast-enhanced and contrast-enhanced CT was performed on 12 subjects (10 male and 2 female; age 18-64 years; mean age 57 years) in whom SBCs had been discovered incidentally on panoramic radiographs during routine dental treatment. MRI was also performed on 3 of the 12 subjects. Results: No submandibular gland tissue was seen in the SBCs in any of the cases. However, fatty tissue of low attenuation was found in the SBCs in all cases on CT images. Blood vessels were seen in the SBCs in 10 cases, and enhanced soft tissue in contact with the bone cavity wall was seen in the SBCs in 2 cases. Blood vessels in the SBCs were observed on MR images in all three cases. Dilatation of the cavity blood vessels was seen in all 10 cases. Slight tortuosity of the blood vessels was seen in 4 of the 10 cases. Conclusions: Examination of contrast-enhanced CT images and MR images revealed that the contents of SBCs were not aberrations of the submandibular gland, as has generally been thought, but fatty tissue, blood vessels and soft tissue. - T Kanayama, K Minowa, N Inoue, T Yamaguchi, S Yoshida, T Kawasaki JOURNAL OF DENTAL RESEARCH 79- (1) 85 -89 2000/01 [Not refereed][Not invited]
Many reports have demonstrated significant region-dependent differences in the fiber-type composition of the human masseter muscle. Therefore, it is considered that there is intramuscular heterogeneity of metabolic activity in the muscle. The present study was carried out, with two-dimensional Chemical Shift Imaging, to detect differences between the deep and superficial parts of the human masseter muscle at rest. Masseter muscle from 11 volunteers, from 20 to 27 years old, was examined, and characteristic spectra of the inorganic phosphate (Pi), phosphocreatine (PCr), and alpha-, beta-, and gamma-adenosine triphosphate (ATP) from each part of the muscles were obtained. In this study, the deep and superficial parts of the masseter muscle were distinguished by the existence of aponeurosis. The Pi/PCr, PCr/beta-ATP, and Pi/beta-ATP ratios as well as the pH in the deep and superficial parts were calculated from the peak spectra. Compared with the deep part, the Pi/PCr of the superficial part was lower (p < 0.05) and the PCr/beta-ATP was higher (p < 0.01). The Pi/beta-ATP and pH showed no significant differences between the two parts. The results indicate that the superficial part of the masseter muscle contains more PCr than the deep part, and this may be related to functional differences between these two parts. In future examinations of the metabolic activity of the human masseter muscle, the deep and superficial parts must be measured separately. - Kazuyuki Minowa, Nobuo Inoue, Taihiko Yamaguchi, Yasunori Totsuka, Tsuyoshi Sawamura, Keiichi Ohmori, Motoyasu Nakamura, Kazuyuki Minowa Oral Radiology 16- (1) 9 -15 2000 [Not refereed][Not invited]
31P-MRS (Magnetic Resonance Spectroscopy) is the only noninvasive technique capable of measuring high-energy phosphate compounds in muscle tissue. In this study, we used 31P-MRS to analyze the energy metabolism at rest in the masseter muscle of TMD patients who showed clinical symptoms in the masseter muscles. The subjects were 10 TMD patients who had complaints of pain and contracture in the masseter muscles, and 10 normal subjects. RESULTS 1. A clear decrease in PCr in the masseter muscle tissue was seen in all of the patients in this study. 2. A clear increase in Pi in the TMD patients was not seen despite a decrease in PCr. 3. The difference in pH between the normal subjects and TMD patients was not significant. In the TMD patients, the recovery of the PCr was delayed, because of that, a decrease of PCr was suggested by 31P-MRS. - SAWAMURA Tsuyoshi, MINOWA Kazuyuki, ABE Satoru, OHMORI Keiichi, NAKAMURA Motoyasu, MIYASAKA Kazuo Oral Radiol. 14- (2) 95 -105 1998/12/01
- K Minowa, N Inoue, Y Ashikaga, S Yoshida, Y Totsuka, M Nakamura ORAL SURGERY ORAL MEDICINE ORAL PATHOLOGY ORAL RADIOLOGY AND ENDODONTICS 86- (3) 275 -279 1998/09 [Not refereed][Not invited]
Objectives. The main objective of this study was to compare the actual distribution and thickness of aponeuroses in cadavers with the distribution and thickness as determined by means of magnetic resonance imaging for the sake of evaluating magnetic resonance imaging as a diagnostic modality for assessing masseter muscle aponeuroses. Study design. The aponeuroses of 26 masseter muscles from 13 intact cadavers were examined by magnetic resonance imaging. Results. The ratio of concordance between gross findings and magnetic resonance imaging findings was 99.0%, although depiction of thin parts of he aponeuroses on magnetic resonance imaging was poor. Conclusions. Magnetic resonance imaging was useful as a diagnostic modality in the assessment of masseter muscle aponeuroses. Aponeuroses were distributed throughout almost the entire masseter muscle, although almost no aponeuroses were seen below the lower half of the anterior margin. This was thought to be a characteristic finding of masseter aponeuroses. - SAWAMURA Tsuyoshi, MINOWA Kazuyuki, ABE Satoru, OHMORI Keiichi, NAKAMURA Motoyasu, MIYASAKA Kazuo 歯科放射線 37- 50 -50 1997/09/10
- K. Minowa, S. Abe, T. Sawamura, K. Obinata, K. Ohmori, M. Nakamura Oral Radiology 13- (1) 45 -49 1997 [Not refereed][Not invited]
Methods of reducing susceptibility artifacts, which invariably occur in MRI examinations of the head and neck region, were investigated in healthy subjects and in patients with head and neck disease. It was found that MRI examination of the head and neck region can be improved by setting the read- out direction in the axial cross-sectional image in the anteroposterior direction and by making TE as small as possible. - SAWAMURA Tsuyoshi, MINOWA Kazuyuki, ABE Satoru, OHMORI Keiichi, NAKAMURA Motoyasu, MIYASAKA Kazuo 歯科放射線 36- 79 -79 1996/09/01
- MINOWA Kazuyuki, ABE Satoru, OHMORI Keiichi, HOSOKAWA Yoichirou, YAMASAKI Michio, HIRANO Masayasu Journal of Oral Surgery Society of Japan 38- (6) 973 -981 1992 [Not refereed][Not invited]
MRI studies were performed on 29 patients with tongue tumors.26 cases were fresh, others were recurrent.Signal intensity of tongue tumor was not characteristic and specific, and it was a low-iso signal on T1 weighted image (WI), heterogeneously iso-high signal intensity on T2 WI, heterogeneous enhancement on gadolinium-DTPA enhanced image compared to muscle signal intensity.
In 3 of 29 patients, the tongue tumor invaded to the mandible.With regard to the grasping tumor invasion to the mandible, the STIR method was superior to T1, T2 WI of the spin echo method.Dynamic enhanced MR images were performed in 6 of 29 patients. Dynamic.change of signal intensity after gadolinium-DTPA administeration were assessed with fast low angle shot imaging.
On dynamic study at about 20 seconds after gadolinium-DTPA injection, the first signal intensity in the periphery of the tumor gradually began to increase.Maximum signal intensity of the tumor showed at about 70 seconds after gadolinium-DTPA injection. In search from 0 to 5 minutes, after the tongue tumor showed maximum signal intensity, its signal maintain the maximum.Necroic and peritumorous edema showed a significantly lower and more gradual increase in signal intensity than adjacent neoplastic tissue on dynamic enhanced MRI. - Kazuyuki MINOWA, Satoru ABE, Keiichi OHMORI, Yoichirou HOSOKAWA, Michio YAMASAKI, Masayasu HIRANO Japan Journal of oral maxillo facial Surgery 38- (6) 973 -981 1992 [Not refereed][Not invited]
MRI studies were performed on 29 patients with tongue tumors.26 cases were fresh, others were recurrent.Signal intensity of tongue tumor was not characteristic and specific, and it was a low-iso signal on T1 weighted image (WI), heterogeneously iso-high signal intensity on T2 WI, heterogeneous enhancement on gadolinium-DTPA enhanced image compared to muscle signal intensity.
In 3 of 29 patients, the tongue tumor invaded to the mandible.With regard to the grasping tumor invasion to the mandible, the STIR method was superior to T1, T2 WI of the spin echo method.Dynamic enhanced MR images were performed in 6 of 29 patients. Dynamic.change of signal intensity after gadolinium-DTPA administeration were assessed with fast low angle shot imaging.
On dynamic study at about 20 seconds after gadolinium-DTPA injection, the first signal intensity in the periphery of the tumor gradually began to increase.Maximum signal intensity of the tumor showed at about 70 seconds after gadolinium-DTPA injection. In search from 0 to 5 minutes, after the tongue tumor showed maximum signal intensity, its signal maintain the maximum.Necroic and peritumorous edema showed a significantly lower and more gradual increase in signal intensity than adjacent neoplastic tissue on dynamic enhanced MRI. - MINOWA Kazuyuki, OHMORI Keiichi, HOSOKAWA Yoichiro, YAMASAKI Michio, HIRANO Masayasu Journal of Oral Surgery Society of Japan 37- (11) 1802 -1809 1991 [Not refereed][Not invited]
Cavernous hemangioma is common in the head and neck region, and pathologically cavernous hemangioma characterized by small feeding arteries and large blood pools.
Angiography and computed tomography have not demonstrated the whole extension of these lesions. 9 patients with cavernous hemangioma were evaluated with magnetic resonance imaging in this study. MRI could clearly demonstrate cavernous hemangiomas with good contrast to normal tissues.
Cavernous hemangiomas showed losv-iso signal intensity compared to the muscle on the Ti weighted image and isu-high signal intensity on T2. All cases did not show a flow void on the proton density image that is most sensitive to flow, and were enhanced by Gd-DTPA.
Especially, T2 weighted and Gd-DTPA enhanced images were useful to demonstrate these lesions.
Intramuscular cavernous hemangiomas in the head and neck region were characterized by local muscle atrophy and septum formation. - Kazuyuki MINOWA, Satoru ABE, Yoichirou HOSOKAWA, Keiichi OHMORI, Michio YAMASAKI, Masayasu HIRANO Japan Journal of oral maxillo facial surgery. 37- (12) 2054 -2059 1991 [Not refereed][Not invited]
We examined whether magnetic resonance imagings (NIRI) after gadolinium-DTPA administration were clinically more useful than nonenhanced MRI in 17 patients with paranasal sinus noeplasm. Seventeen patients underwent MR I both with and without gadolinium-DTPA, and CT. Six of the seventeen cases demonstrated coexisting neoplasm and mucoceles, polyps. Though nonenhanced MRI enabled correct differentiation of 3 of these 6 lesions, gadolinium-enhanced MRI enabled correct differentiation of all 6 lesions.
We concluded that gadolinium-enhanced MRI was useful for differentiating neoplasms and mucoceles or polyps in the paranasal sinuses. - Kazuyuki MINOWA, Keiichi OHMORI, Yoichiro HOSOKAWA, Michio YAMASAKI, Masayasu HIRANO Japan Journal of oral maxillo facial surgery 37- (11) 1802 -1809 1991 [Not refereed][Not invited]
Cavernous hemangioma is common in the head and neck region, and pathologically cavernous hemangioma characterized by small feeding arteries and large blood pools.
Angiography and computed tomography have not demonstrated the whole extension of these lesions. 9 patients with cavernous hemangioma were evaluated with magnetic resonance imaging in this study. MRI could clearly demonstrate cavernous hemangiomas with good contrast to normal tissues.
Cavernous hemangiomas showed losv-iso signal intensity compared to the muscle on the Ti weighted image and isu-high signal intensity on T2. All cases did not show a flow void on the proton density image that is most sensitive to flow, and were enhanced by Gd-DTPA.
Especially, T2 weighted and Gd-DTPA enhanced images were useful to demonstrate these lesions.
Intramuscular cavernous hemangiomas in the head and neck region were characterized by local muscle atrophy and septum formation.
Books etc
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- 日本学術振興会：科学研究費助成事業Date (from‐to) : 2020/04 -2023/03Author : 竹内 明子, 的場 光太郎, 箕輪 和行, 兵頭 秀樹, 亀田 浩之, 長谷部 晃研究期間２年目では、ご遺体（法医解剖体）における死後CT画像取得時に、全身大血管（大脳動脈、頚動脈、胸部大動脈、腹部大動脈）における壁肥厚やプラークによる血管狭窄に対する画像的検索を進めており、これらの症例数は累計で18件となりました。 検体採取を行ったそれぞれの症例において画像的検索と法医解剖所見を比較することで、歯周病細菌の存在分布検証に用いる検体（主要血管壁）の採取部位をそれぞれ決定しました。また、採取した血管壁を用いて、凍結切片の作成により、病理学的検索の可能性を模索し、免疫染色による歯周病菌の同定（存在分布の確認）についても追加の検討を行っています。 予備実験において、死後CT画像にて血管壁に石灰化が見られる場合、DNA採取が困難である場合があり、血管壁の石灰化の度合いに対して、死後CT画像上でのスコア化を追加検討しています。 また、法医解剖体の口腔内所見採取時に、歯周病進行状況、残存歯数、歯科治療痕等のデータ収集をさらに進めています。検体数の増加により、前年度に取得した歯周ポケット検査による歯周病進行度のスコアに変更が生じたため、再度検討を行っています。検体採取については２年目も順調に進んでいますが、検体数の増加にともない、検体の口腔内所見（残存歯数や歯科治療所見）が多様に見られ、また、高齢のご遺体（解剖体）では、残存歯数が少ない場合があり、初年度に採取した口腔内所見によるスコア化に関して、調整が必要となっています。
- Japan Society for the Promotion of Science：Grants-in-Aid for Scientific ResearchDate (from‐to) : 2018/04 -2022/03Author : minowa kazuyukiThis study sought to clarify the relationship between oral air space volume and obstructive sleep apnea syndrome (OSAS) onset, which is influenced by multiple factors, such as jawbone, dentition morphology, and oral soft-tissue volume. (1)50 subjects from deceased cases were divided into two groups: OSAS (25 subjects) and controls (25 subjects). (2) 33 subjects from clinical cases were divided into two groups: OSAS (9 subjects) and controls (24 subjects). In all cases, the CT images of the facial region were obtained, and four parameters of oral area volume were analyzed in deceased and clinical cases, and comparisons and analyses were performed between OSAS and control cases. In deceased cases, oral soft-tissue volume (OSV), oral air-space volume (OAV), and the ratio of OAV to OSV (%air) showed a significant correlation. In clinical cases, OAV and %air showed a significant correlation. Furthermore, the evaluation including the pharyngeal area were similar to this results.
- Japan Society for the Promotion of Science：Grants-in-Aid for Scientific ResearchDate (from‐to) : 2015/04 -2019/03Author : Satoh KaoruWe recorded brain activity stimulating periodontium with MEG to verified part of cerebrum and analyzed frequency using SPM8 method. As a result, the power value of alpha waves during rest and closing eyes was reduced by continuous mechanical stimulation on the periodontium. SPM analysis revealed that the activities located in the centriciput- occiput region. But the difference of region was noticed with and without stimulation. On the other hand, it required a study of correlation between power value and VAS.
- Japan Society for the Promotion of Science：Grants-in-Aid for Scientific ResearchDate (from‐to) : 2013/04 -2017/03Author : Minowa KazuyukiThe aim of our study is to develop the MR microscope that non-invasively will be able to visualize pathological information of the squamous cell carcinoma in the oral cavity by Q space image technique belonging to the diffusion weighted images. The parameter of the Q space imaging technique was established for this study. The comparison between the parameter of the Q space imaging and specimen of the squamous cell carcinoma in the oral cavity, also between the parameter of the Q space imaging and routine diagnostic image for the oral cancer were evaluated. The correlations between some of the parameters in the Q space imaging and cell growth factor, routine diagnostic image for the oral cavity cancer were obtained.
- Japan Society for the Promotion of Science：Grants-in-Aid for Scientific ResearchDate (from‐to) : 2011/04 -2015/03Author : SATOH Kaoru, YAMAGUCHI Taihiko, MAEZAWA Hitoshi, MINOWA Kazuyuki, OKADA KazukiWe analyzed brain activity with MEG to establish a method for objective evaluation of correlation between discomfort and intensity of occlusal contacts. Oral somatosensory was stimulated. As a result, power value of alpha waves during rest and closing eyes was reduced by continuous mechanical stimulation on the periodontal membrane. The activity was generated in the centriciput- occiput region. It was suggested that this method was effective to cause discomfort on periodontal membrane.
- Japan Society for the Promotion of Science：Grants-in-Aid for Scientific ResearchDate (from‐to) : 2009 -2011Author : MINOWA Kazuyuki31P-CSI was obtained in the head and neck region by CSI on 3T MR apparatus. The experiment data in normal volunteer resulted the sequence of 31P-CSI was TR/TE:4500/0.1msec, acquisition time:32, and interesting volume was more than 5.5cm^3. The half width on 31P-CSI was 0.5-1.1ppm in the head and neck region. 31P-CSI in the skull base and pharyngeal surface region was not able to obtain due to susceptibility artifact.
- Japan Society for the Promotion of Science：Grants-in-Aid for Scientific ResearchDate (from‐to) : 2002 -2003Author : YAMAGUCHI Taihiko, TOTSUKA Yasunori, SATOH Kaoru, KOMATSU Kosetsu, MINOWA Kazuyuki, INOUE NobuoThe purpose of this study was to clarify whether physical therapies and occlusal splints are effective against muscle fatigue of temporomandibular disorders (TMD) patients from the point of view of blood flow state.
Blood flow of masseter muscles were measured using 3-wave-length near-infrared spectroscopy, and the blood flow parameters were total hemoglobin volume (THb), oxygenated hemoglobin volume (OXHb), deoxygenated hemoglobin volume (deOXHb), and oxygen saturation level (StO2). Subjects for the physical therapies were healthy subjects with no history of muscle pain in the masticatory system, while subjects for the splint therapy were TMD patients with masticatory muscle symptoms who used stabilization splints. The physical therapies applied were 20-minite hot pack and 30-minite myo-monitor. 1)THb,OXHb and StO2 after the hot pack application were significantly larger than those during resting. The deOXHb showed no significant difference between the values before and after the hot pack application. The results suggest that the blood flow state of human masseter muscles can be influenced by a hot pack, and that the effect of hot pack therapy is to increase regional blood volume and that it creates the advantageous conditions for aerobic energy metabolism. 2)There was no no significant difference between the values before and after myo-monitor application in all parameters of blood flow. 3)During resting, mean values of StO2 with the splint were significantly larger than those without the splint During and after clenching, THb with the splint was significantly larger than that without the splint. The results suggest that the blood flow of masseter muscles can be influenced by wearing stabilization splints in the short term. However, effect of longtime using of splints is still unknown. Further studies on longitudinal change in blood flow stale of masticatory muscles in wearing splints are needed. - Japan Society for the Promotion of Science：Grants-in-Aid for Scientific ResearchDate (from‐to) : 1999 -2000Author : INOUE Nobuo, MINOWA Kazuyuki, YAMAGUCHI Taihiko, TOTSUKA YasunoriThe purpose of this study was to clarify the the influences of regional tissue blood flow volume (RTVF volume) on energy metabolism in deep and superficial part of masseter muscle (Mm) 1. Establishment of 31P-Chemical Shift Imaging (CSI) for human Mm. We have succeeded in analyzing energy metabolism in both deep and superficial part of Mm. It has become clear that the superficial part of Mm contains more phosphocreatine (PCr) than deep part. This result suggests that deep and superficial part of Mm need to be measured separately in analyzing energy metabolism. 2. Establishment of analyzing methods of RTVF volume. A three wavelength spectrophotometric method were used. As the parameters of RTVF volume, total hemoglobin (Hb) volume, and ratio and period of change in Hb were selected. It was demonstrated that RTVF volume in Mm changes as head and/or upper half of body lean, and that we need to keep head and body position stable. 3. Establishment of condition for exercise task. Among several condition for exercise task such as maximal clenching, gum chewing and so on, 10 kgf clenching for 20 sec. was considered to be adequate. 4. Measurements in healthy people and patients with temporomandibular disorders (TMD). As for the energy metabolism, PCr in Mm of TMD patients was lower than that of healthy people. In other words, it was suggested that energy level of Mm in TMD patients was lower than that of healthy people. However, we could not obtain obvious conclusion concerning RTVF volume because of wide variation of the data. Therefore, to diminish the influence of the wide variation and to confirm the relation between energy metabolism and RTVF volume, we need to gather more data in further studies by using the analyzing methods established in this study.
- Japan Society for the Promotion of Science：Grants-in-Aid for Scientific ResearchDate (from‐to) : 1998 -1999Author : YAMAGUCHI Taihiko, KOMATSU Kosetsu, INOUE Nobuo, TOTSUYA Yasunori, SATOH Kaoru, MINOWA KazuyukiIn order to clarify the influences of chronic decrease in blood flow volume on energy metabolism in masticatory muscles, we tried to establish the method for obtaining 31P-spectra by using NMR, and tried to make the the wister rat model in which the blood flow volume of the gastrocneminus muscles and the soleus muscles chronically continued to decrease with bound dominant artery. As the parameters of regional tissue blood flow volume, oxygen saturation level of blood (StO2) and total hemoglobin (Hb) volume were measured using a three wavelength spectrophotometric method. The results were as follows; 1. Using a 7T NMR and a surface coil (25mm diameter), we obtained the 31P-spectra of ATP sample, and we were able to detect peaks of α, β, γ-ATP. However, the 31P-spectra of rat muscles were not obtained clearly because of noise from surrounding tissues. This problem is expected to be solved by improvement in program of control system of the NMR. 2. We obtained precise reproduciblity in measurement of StO2 and Hb volume, when we fixed both the probe of measuring apparatus and the leg of rats using devices which we made for fixation appropriately. 3. Just after binding of the artery, the value of StO2 and total Hb volume declined by about 30% and 70%, respectively. These levels continued one or two months after binding. Therefore, it was suggested that we could make the relatively chronic model in which the blood flow volume of the gastrocneminus muscle and the soleus muscles decreased obviously.
- 日本学術振興会：科学研究費助成事業Date (from‐to) : 1997 -1998Author : 箕輪 和行^<31>P-CSI(^<31>P-ChemicalShiftImaging)^<31>P-CSIでは新たに設定したパラメータ(TR:330msec,flipangle:51degrees,acquisition:9,matrixsize:16×16,FOV:320mm,検査時間12分40秒) で、正常者咬筋の浅層と深層それぞれ腱膜を指標として分離し、各層からのスペクトルを得ることに成功した。その結果、咬筋の浅層と深層ではフォスフォクレアチンの存在量に有意な差が見られ、筋線維の違いによる代謝の違いが示唆された。さらに、内側翼突筋、外側翼突筋、側頭筋からもスペクトルを得ることに成功した。^<31>P-CSIにて内側翼突筋は咬筋浅層とフォスフォクレアチンの存在量で有意な差は見られず、両者は同様の代謝をしている可能性が示唆された。しかし、外側翼突筋、側頭筋からのスペクトルは筋自体の体積が小さく、周囲組織からの信号の混入が多く、撮像パラメータの検討が必要であると思われた。^1H-MRSshinglevoxcel (size;1×2×4cm:8ml)を用いて咬筋全体からスペクトルを得ることに成功した。パラメータは新たに以下のように設定した。TR:2000msec,TE:135msec,acquisition:256,FOV:300mm,検査時間10分である。voxcel内の半値幅は約0.2ppmであった。安静時における正常者の咬筋からは乳酸は検出されなかったが、最大噛みしめの運動を負荷した場合、僅かな乳酸の二峰性のピークが認められた。時間とともに、乳酸のピークが減少する傾向にあり、血流との関係が問題となるものと考えられた。funcionalMRI咀嚼の運動として用いたのは運動により頭部のずれが少ない中心咬合位での軽いタッピングである。運動を負荷すると負荷にに伴って咀嚼の一次運動野の信号が3〜5%上昇した。運動負荷に伴って、咀嚼運動野の信号が全体的に上昇する傾向が見られた。
- Japan Society for the Promotion of Science：Grants-in-Aid for Scientific ResearchDate (from‐to) : 1996 -1997Author : YAMAGUCHI Taihiko, SATOH Kaoru, MINOWA Kazuyuki, KOMATSU Kosetsu, INOUE Nobuo, TOTSUKA YasunoriThe purpose of this study was to investigate the mechanism of the masseter muscle contracture which caused resistance to stretch of jaw. 1.In clinical examinations, most of the TMD patients with contracture had little muscular pain during rest, jaw closing, and biting. During maximal jaw opening, they felt hard resisting power of their masseter muscles, but did not feel strong pain. The pain during maximal jaw opening was mostly slight and dull. These characteristics were different from characteristics of TMD patients with typical muscular pain. 2.In EMG examinations, abnormal pattern of EMG activity was not found apparently during rest jaw closing and biting. However, the EMG during jaw opening showed hyperactivity of masseter muscles. These two results suggest that the mechanism of masseter muscle contracture will be different from that of muscular pain. In other words, it is likely that the masseter muscle contracture is not necessarily due to the hyperactivity of masseter muscles during rest, jaw closing and biting. 3.In analysis of muscular energy metabolism (31P-magnetic resonance spectroscopy) , phosphocreatine (PC_r) /beta-ATP values of the patients with contracture was lower than normal controls. This result suggested that the PC_r would be consumed and the masseter muscles would be on a low level of latent energy. Therefore the improvement of peripherad blood flow using physical treatment such as massage of muscles will be necessary for the patients with contracture.
- 日本学術振興会：科学研究費助成事業Date (from‐to) : 1996 -1996Author : 箕輪 和行今回は顎関節症患者の咬筋内の乳酸を測定する前段階として、正常者ヒト咬筋内の乳酸を測定するための1H-MRSのプログラムの開発を目的として実験を行った。 対象は正常ボランティアの咬筋とし、使用装置は北海道大学医学部附属病院所有のMR装置、Seimens社製のVISION(静磁場強度1.5tesla)とMRIおよびMRS両用のhead coilを使用した。まずはガントリ-の周囲にある12個のコイルを調製して、コイル全体の磁場を均一にするプログラムを作成した。さらに、T1強調像にて撮像し、咬筋の位置を3次元的に確認し、周囲の脂肪組織が関心領域内に入らないように咬筋内に関心領域を設定し、この関心領域内の磁場を均一にするように12個のコイルを調整した。関心領域は咬筋の形状を考え直方体とし、被験者により多少の変形を加え、その体積は約10ml前後であった。乳酸の検出に優れているといわれているspin echo法のSVS (single voxcel spectroscopy)を使用し、信号を収集場合の条件はTR=2000msec, TE=270msec,積算回数=300回とした。信号収集時間は6分であった。 結果、正常者の咬筋からは安静時には、乳酸のピークは認められなかった。しかしながら、可能な限り最大噛みしめを持続させた場合にのみ、乳腺のピークが得られた。
- Japan Society for the Promotion of Science：Grants-in-Aid for Scientific ResearchDate (from‐to) : 1994 -1995Author : YAMAGUCHI Taihiko, KOMATU Kosetu, UEDA Yasuo, MINOWA Kazuyuki, INOUE Nobuo, TOTSUKA YasunoriThe purpose of this study was to verify the relationship between electromyograph (EMG) and energy metabolism in masseter mucles of TMD patients. The EMG data were compared with energy metabolism data analyzed by 31P-MRS (Magnetic Resonance Spectroscopy). The results were as follows ; 1. Before and after fatigue-loading, the power spectral analysis of EMG showed the similar tendency to 31P-MRS analysis. It was suggested that the power spectral analysis of EMG might reveal the state of muscle fatigue and energy metabolism in masseter muscle. 2. In the chewing rhythm analysis by EMG,the mean of CV (coefficiency of variation) in TMD patients suffering from pain and contracture of masseter muscles was higher than that in normal subjects. But there was little correlation between the result of CV analysis and that of 31P-MRS analysis. 3. The mean of interval/cycle time ratio in TMD patients suffering from pain and contracture of masseter muscles was higher than that in normal subjects. The result of interval/cycle time analysis was correlative with the result of energy metabolism analysis by 31P-MRS. 4. In one TMD patient, 31P-MRS analysis showed improvement of muscle fatigue after treatments, but interval/cycle time ratio was not changed evidently. In this patient, the ratio before treatment was almost in nomal range, because the border of burst was not obvious and the duration of burst was enlarged abnomally. After treatment the border of burst became clear and the burst shape became normal. This results suggest that the analysis of interval/cycle time ratio must be done together with the burst shape analysis.
- 日本学術振興会：科学研究費助成事業Date (from‐to) : 1994 -1994Author : 箕輪 和行ヒト咬筋に対する表面コイル法による31P-スペクトロスコピーの方法を本研究代表者は平成4年度の科学研究費を使用して確立し、その成果を顎関節学会誌(P14-25 vol6 No.2 1994)に発表した。今回はさらに領域選択法、ISIS(image selected in vivo spectroscopy)法を使用し、より正確にヒト咀嚼筋群の個々のスペクトルを得ようとする試みを行った。対象被験者は正常ボランティア10名であり、使用機種は静磁場強度1.5teslaの臨床機種(MAGNETOM)を使用した。 結果および結論 1.領域選択法について 理論的には信号収集領域を直方体とすることは可能であるが、実際にはその領域内での磁場の均一性が得られず、領域設定は立方体のみ可能となった。したがって、咀嚼筋群のような直方体の形状を有する筋の場合、信号収集領域が筋全体を含むためには不可能となった。 2.ISIS法は信号収集領域が小さく、表面コイル法に比べ信号が弱く、そのため加算回数を512、1024回とする必要があり検査時間もそれぞれ約26分、52分となった。 3.バックグランドノイズにスペクトルが埋没することが多く、より良いスペクトルを得るためには被験者の強力がかなり必要な検査であった。 4.実際スペクトルは10例中1例の咬筋から得られた。その他の、内外側翼突筋、側頭筋は体積がかなり小さく、形態も複雑であり、ISIS法では選択領域の磁場の均一性が確保できずスペクトルは得られなかった。今後、対象筋肉の形態に合わせた領域の設定、領域選択法の確立がなされて初めて安定したISIS法によるスペクトルが得られると思われた。
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- Radiological diagnosis in head and Neck