歯科放射線
Online ISSN : 2185-6311
Print ISSN : 0389-9705
ISSN-L : 0389-9705
40 巻, 2 号
選択された号の論文の7件中1~7を表示しています
  • 神田 重信, 湯浅 賢治, 中山 英二, 河津 俊幸
    2000 年 40 巻 2 号 p. 109-121
    発行日: 2000/06/30
    公開日: 2011/09/05
    ジャーナル フリー
    Palpation and imaging procedures such as computed tomography (CT), ultrasonography (US), magnetic resonance imaging (MR), radioisotope imaging (RI) and lymphography are examined for predicting cervical lymph node metastasis in head and neck cancer patients. We reviewed the criteria for metastasis and diagnostic accuracy (sensitivity, specificity and accuracy) of these diagnostic procedures in previous reports. We then discussed the efficiency of these diagnostic procedures for predicting cervical metastasis. Furthermore, our criteria and its positive predictive value (PPV) and negative predictive value (NPV) with CT, B-mode US and power Doppler US, and the methods of CT and US examinations in our department were reported. In previous reports, it was reported that sensitivity was 47%-97%, specificity was 38-92%, accuracy was 69-88% with palpation. The diagnostic efficiency of lympography was considered to be low. Now this procedure is not used in diagnosing cervical metastasis. 18FDG-PET was preformed mainly. Its sensitivity and specificity were 50-93% and 77-100%, respectively. With CT, sensitivity and specificity were 49%-100%, 38%-100%, respectively. With MR, sensitivity and specificity were 47%-100%, 48%-100%, respectively. With B-mode US, sensitivity and specificity were 58%-95%, 37%-96%, respectively. With Doppler US, sensitivity and specificity were 55%-98%, 77%-100%, respectively. In the results of our study, PPV for predicting metastasis with CT was 91%. PPV for predicting metastasis with B-mode US were 97%. PPV for predicting metastasis with power Doppler US were 87%.
  • 金田 隆
    2000 年 40 巻 2 号 p. 122-128
    発行日: 2000/06/30
    公開日: 2011/09/05
    ジャーナル フリー
    The development of imaging modalities according to computer technology has proven to be a great breakthrough in diagnostic imaging. In this article, the role of imaging modalities, especially computed tomography (CT) and magnetic resonance imaging (MRI), for imaging of the oral cavity, submandibular region and metastatic cervical lymph nodes is discussed. Oral mucosal masses include benign neoplasms, minor salivary gland tumors, and malignant tumors. Staging of squamous cell carcinomas must focus on deep invasion, spread to the mandible and lymph nodes. The main entities are discussed with regard to which study is indicated and whether imaging can suggest a specific diagnosis. The imaging approach to these lesions is also discussed.
  • 河井 紀子, 若狭 亨, 浅海 淳一, 此内 浩信, 岸 幹二
    2000 年 40 巻 2 号 p. 129-137
    発行日: 2000/06/30
    公開日: 2011/09/05
    ジャーナル フリー
    Tooth root resorption due to an adjacent and/or involved tumor is considered to be one of the most important radiographic features for differentiating between benign and malignant tumors in the oral and maxillofacial region. Few studies have reported tooth resorption related to malignant tumors despite many reports of tooth resorption caused by benign tumors. This study was to investigate the frequency of root resorption and the relationship between the type of tumor extension and the root resorption in squamous cell carcinoma that is the most frequent type of oral cancer. Forty-five patients with squamous cell carcinoma involving the tooth root were examined retrospectively using radiographic findings. The type of tumor extension was divided into 2 patterns, the marginal type: tumor invaded from the alveolar margin and the apical type: tumor invaded from the root apex. The type of tooth resorption was divided into spiked type and knife-edge type according to the shape of the resorped root. In 45 cases showing tooth roots involved by the tumor, root resorption was recognized in 19 cases (42.2%). In 37 cases of the marginal type, root resorption was recognized in 15 cases (40.5%), all of which showed spiked type root resorption. All cases of the marginal type demonstrated gingival carcinoma. The remaining 8 cases were found to be apical type and all of these were maxillary cancer that filled more than two thirds of the maxillary sinus and extended into the oral region involving the tooth roots. Four of these 8 cases showed root resorption (50.0%), all of which were knife-edge type. In conclusion, tooth root resorption in squamous cell carcinoma may occur more frequently than previously considered. Only the spiked type was observed when root resorption occurred in the marginal type carcinoma. In the case of apical type maxillary carcinoma involving the oral and maxillary sinus region, knife-edge type root resorption may occur rather than the spike type.
  • 今中 正浩, 小林 馨, 山本 昭, 五十嵐 千浪, 湯浅 雅夫, 木村 由美
    2000 年 40 巻 2 号 p. 138-144
    発行日: 2000/06/30
    公開日: 2011/09/05
    ジャーナル フリー
    We discuss the relationship between the signal intensity detected in the T2-weighted MR images of the retrodiscal tissue of a patient suffering from a TMJ disc perforation.
    Material and Methods: Using T2-weighted MR images and double-contrast arthrotomographs with fluoroscopic arthrography, the TMJ's of 93 patients were obtained for diagnostic observations of disc perforations. Observations of each MR image were made at two separate times. Accuracy, sensitivity, specificity and positive and negative predictive values of the disc perforation were determined using high signals detected in the MR images. We also calculated the kappa coefficient of Cohen for examinating the reliability of the observer.
    Results: In the first observation, the high signal in the MR image of the retrodiscal tissue was detected in 92% of the perforation group (that is, 35 of 38 patients), and 46% (25 of 55 patients) of the non-perforation group. In addition, a low signal was detected in 8 % of the perforation group (3 of 38 patients), and 54% (30 of 55 patients) of the non-perforation group. In the second observation, a high signal was detected in 87% of the perforation group (33 of 38 patients), and 26% (16 of 55 patients) of the non-perforation group. In addition, a signal was detected in 13% of the perforation group (5 of 38 patients), and 74% (39 of 55 patients) of the non-perforation group. A significant difference (p<0.05) was obtained between the perforation group and the non-perforation group in high signal frequencies detected during both observations. When the high signal was regarded as on indication of a disc perforation, the sensitivity in diagnostic detection was 70-77%. In addition the negative predictive value was 89-91%. The kappa coefficient of Cohen showing the observer's reliability was 0.759, which can be classified into the category of substantial. This value was also considered to be clinically acceptable.
    Conclusion: The frequency of high signals was significantly higher in the perforation group of patients. A high signal is considered to be an accurate indicator of a disc perforation on MR images. In addition when a low signal was observed on T2-weighted MR images of the retrodiscal tissue, we were able to discount the diagnosis of a disc perforation. This method using the signal intensity of MR images as a standard is effective one for detecting disc perforations.
  • 新井 嘉則, 橋本 光二, 岩井 一男, 篠田 宏司
    2000 年 40 巻 2 号 p. 145-154
    発行日: 2000/06/30
    公開日: 2011/09/05
    ジャーナル フリー
    The limited cone-beam CT known as Ortho-CT has been used in clinical examination since 1997. On the basis of this experience, we developed a new style of limited cone-beam CT for practical use, called “3DX Multi image micro CT” (3DX). The purpose of this study was to introduce this new style of limited cone-beam X-CT by comparing it to the prototype (Ortho-CT). Material and Methods: 3DX was compared with Ortho-CT regarding the fundamental efficiency. The skin doses of 3DX and Ortho-CT were measured using TLD on a Rando phantom. The resolutions of both systems were evaluated with MTF (modulation transfer function). The subjective image quality was evaluated on the following anatomical landmarks : the inner ear, temporomandibular joint (TMJ), maxillary first molar, mandibular first molar. Five dental radiologists and two otolaryngologists evaluated the quality of 3DX images comparing then with that of Ortho-CT images for the same observation point. The five-point scale ranged from one point (inferior) to five (superior). Results: The skin doses were 1.07 mSv with 3DX and 1.19 mSv with Ortho-CT. The skin dose of “3DX” was almost the same as that of Ortho-CT. The resolutions of Ortho-CT were 0.6 line pair/mm (horizontal) and 0.9 line pair/mm (vertical) on the MTF (0.5). The resolution of 3DX was 1.1 line pair/mm (horizontal) and 1.3 line pair/mm (vertical). The subjective image quality of 3DX was better than that of Ortho-CT at every observation point. The minimum score was 3.46, and maximum score was 4.17. There were significant differences with every observation point (p<0.05). Conclusion: On the basis of the clinical experience of Ortho-CT, a new style of limited cone-beam X-CT called “3DX” was developed by us for practical use. The skin dose is almost the same as in the prototype system. The images show very high resolution compared to those of the prototype system. We think that this system is very useful for diagnosis of hard tissue for dental purposes and otology.
  • 加島 正浩, 本田 和也, 新井 嘉則, 上野 正博, 澤田 久仁彦, 岩井 一男, 橋本 光二, 篠田 宏司
    2000 年 40 巻 2 号 p. 155-160
    発行日: 2000/06/30
    公開日: 2011/09/05
    ジャーナル フリー
    TMJ arthrography has been performed with a surgical X-ray television system (fluoroscope) and a tomographic apparatus for patients with disturbance of opening of the mouth. Limited cone beam X-CT for dental use (Ortho-CT) developed by Arai et al, is small and very effective for the small ma.f.illofacial area. We performed TMJ arthrography by using Ortho-CT for TMD patients, and obtained good results, compared with those of MRI. Objects were 13 joints in 12 patients diagnosed as having TMD. As a result, there was a high percentage of agreement with figure and position of the articular disk and it was certain that Ortho-CT had the accuracy similar to that of MRI, because there was no statistically significant difference. We conclude that Ortho-CT is very effective for TMJ arthrography.
  • 2000 年 40 巻 2 号 p. 161-181
    発行日: 2000/06/30
    公開日: 2011/09/05
    ジャーナル フリー
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