日本放射線技術学会雑誌
Online ISSN : 1881-4883
Print ISSN : 0369-4305
ISSN-L : 0369-4305
検索
詳細検索
OR
閲覧
検索
63 巻, 10 号
選択された号の論文の15件中1～15を表示しています
すべての抄録を表示する
    • |<
    • <
    • 1
    • >
    • >|
巻頭言
原著
  • 高速スピンエコー法を用いた造影ダイナミックT1値計測MRIの最適条件の検討
    金澤 裕樹, 宮地 利明, 井上 雄介, 佐藤 修
    2007 年 63 巻 10 号 p. 1127-1132
    発行日: 2007/10/20
    公開日: 2008/01/10
    DOIhttps://doi.org/10.6009/jjrt.63.1127
    ジャーナル フリー
    抄録を表示する抄録を非表示にする
    For the purpose of continual measurement of the T1 value using the FSE (fast spin-echo) sequence and evaluation of the hemodynamics, we assessed T1 values when the imaging parameters were changed. Moreover, with the imaging parameters derived from this study, dynamic contrast-enhanced MR imaging (MRI) was examined in prostatic disease. First, the T1 value before contrast agent injection was measured with imaging parameters that had different TR and fixed TE. Next, dynamic contrast-enhanced imaging data were acquired for the imaging parameters using TE and TR in the same way as before contrast agent injection, and the T1 value of the tissue at contrast enhancement was measured. In the phantom studies, the TSE imaging parameters with short TE, long TR, and few ETL were connected with the mixed sequence. In dynamic study of the prostate, the difference between normal prostate and prostate cancer became clearer with the time-relaxation rate curve than the time-signal curve. This method using TSE is able to evaluate in greater detail information on hemodynamics and to perform dynamic study with the spin-echo sequence in extensive tissues.
    抄録全体を表示
    PDF形式でダウンロード (139K)
ノート
  • ボリュームCTを用いた心機能評価に関する基礎的検討
    丸山 純人, 高橋 俊行, 高橋 良昌, 網師野 直行, 中島 潤也, 加藤 京一
    2007 年 63 巻 10 号 p. 1133-1137
    発行日: 2007/10/20
    公開日: 2008/01/10
    DOIhttps://doi.org/10.6009/jjrt.63.1133
    ジャーナル フリー
    抄録を表示する抄録を非表示にする
    Cardiac images were taken in altered pulse counts on a pulsating cardiac phantom, revolving speed of X-ray tube, image reconstructing mode, and beam pitch with 32 DAS MDCT. The objective of this study was to determine whether conditions of image taking affect calculated values of ejection fraction (EF). Moreover, the EF values measured by left ventriculography (LVG) and by coronary computed tomography (CT) were compared using clinical data of 4 patients who underwent both coronary CT and LVG. On evaluating the pulsating cardiac phantom images, the EF values measured by coronary CT were generally smaller than those measured by LVG. On evaluation of the pulsating cardiac phantom images, the values of end-diastolic volume (EDV) and end-systolic volume (ESV) measured by coronary CT were smaller than those measured by LVG. On the contrary, the EF values measured by coronary CT were bigger than those measured by LVG. The maximal difference between the EF values measured by LVG and those measured by coronary CT was approximately 10% based upon the values measured by LVG.
    抄録全体を表示
    PDF形式でダウンロード (92K)
  • PETにおけるブロック型反復画像再構成法の定量的画質評価―Dynamic RAMLA法とOSEM法の比較―
    松本 圭一, 北村 圭司, 清水 敬二, 村瀬 研也
    2007 年 63 巻 10 号 p. 1138-1144
    発行日: 2007/10/20
    公開日: 2008/01/10
    DOIhttps://doi.org/10.6009/jjrt.63.1138
    ジャーナル フリー
    抄録を表示する抄録を非表示にする
    Purpose: Iterative reconstruction has been successfully used in whole-body PET imaging because of reductions in noise and scanning time. However, there are plural algorithms for image reconstruction such as OSEM, RAMLA and Dynamic RAMLA. Dynamic RAMLA (DRAMA) is an iterative algorithm similar to RAMLA, but the relaxation parameter is controlled in such a way that the propagation of noise from projection data to the reconstructed image. The purpose of this study was to investigate differences in the DRAMA and OSEM algorithms, in terms of real space and frequency space. Method: A whole-body torso phantom (NEMA image-quality phantom) filled with F-18 was scanned with a dedicated PET scanner. The smallest four spheres, with internal diameters of 10, 13, 17, and 22 mm, were filled with F-18 at an 8:1 concentration with respect to the background. The two largest spheres, with diameters of 28 and 37 mm, were not filled with water (empty). The emission scan for a 50 cm axial range varied from 5-20 minutes, to examine the effect of the count statistics on the quality of the reconstructed images. The images were reconstructed with OSEM by changing the number of subsets from 1 to 128 in each study. As to the number of iterations, both iterative reconstruction algorithms were one. As a reference standard, images with maximum counts (60 minutes) were reconstructed with a filtered-back projection method. The quality of the reconstructed images was evaluated in terms of contrast, background variability, and two-dimensional power spectrum analysis. Results: As for the real space results, OSEM with more than 32 subsets decreased contrast because of images with checkerboard noise. The DRAMA algorithm provided stable contrast even when count statistics were poor. A two-dimensional power spectrum analysis also revealed that the OSEM algorithm enhanced noise components in reconstruction with more than 32 subsets. Conclusion: Our preliminary data suggested that the OSEM algorithm requires few iterations with a small number of subsets for whole-body imaging. However, the DRAMA algorithm provides a reasonable signal-to-noise ratio with satisfactory spatial resolution even with one iteration. Especially in clinical whole-body PET, DRAMA was most useful because of its fast convergence and small computer burden.
    抄録全体を表示
    PDF形式でダウンロード (120K)
  • Radiologic-anatomic Correlationによる胸部単純X線画像に描出される胸椎・肋骨陰影の解析
    山口 功, 伊藤 春海
    2007 年 63 巻 10 号 p. 1145-1151
    発行日: 2007/10/20
    公開日: 2008/01/10
    DOIhttps://doi.org/10.6009/jjrt.63.1145
    ジャーナル フリー
    抄録を表示する抄録を非表示にする
    The purpose of this study was to provide an introduction to parsing the radiologic appearance of thoracic vertebrae and ribs. In the study, the radiologic-anatomic correlation technique was applied to promote further understanding of normal chest radiographs. The thoracic vertebrae and ribs of chest radiographs were compared with each macroscopic radiologic and computed tomography (CT) image. The rib parsed the linear shadow of the body of the rib. The macroscopic and radiologic images of thoracic vertebrae and ribs were evaluated to explain their normal radiologic findings. The results of such correlation were summarized as follows: 1) The lamina of the vertebral arch was visualized due to anterior rotation of the upper thoracic vertebrae. 2) The density ratio of the thoracic-vertebrae shadow was almost the same in the vertebral body and vertebral arch. 3) The linear shadow superimposed on the rib corresponded to the inferior margin of the rib. The radiologic-anatomic correlation technique was useful to evaluate normal radiologic findings, and the study was useful to radiological technologists.
    抄録全体を表示
    PDF形式でダウンロード (119K)
臨床技術
  • Multi Detector Row-CTによる右下横隔動脈描出に関する基礎的および臨床的検討
    奥村 悠祐, 鈴木 正行, 武村 哲浩, 高田 忠徳, 河原 和博, 松浦 幸広, 松井 修, 高橋 志郎
    2007 年 63 巻 10 号 p. 1152-1161
    発行日: 2007/10/20
    公開日: 2008/01/10
    DOIhttps://doi.org/10.6009/jjrt.63.1152
    ジャーナル フリー
    抄録を表示する抄録を非表示にする
    To perform transcatheter arterial embolization (TAE) successfully, it is important to obtain information about parasitic arterial supply to the hepatocellular carcinoma (HCC). Among these extrahepatic collateral vessels, the right inferior phrenic artery (RIPA) is the most frequent and important extrahepatic collateral artery supplying the HCC. In the present study, we obtained multi-planar reformation (MPR) images of RIPA using multi detector row computed tomography (MDCT), assessed the ability of MDCT to demonstrate the origin of RIPA, and then analyzed the morphology of the origin. In a basic study using an original phantom simulating vessel origin, the origin was poorly visualized depending on the phantom diameter and angle of the origin to the scanned section. A clinical study was performed in 28 patients with HCC who underwent both MDCT and angiography within a short period. In 19 of 28 patients, RIPA originated at the celiac artery. In 3 patients, RIPA originated at the right renal artery, and in 6, directly at the abdominal aorta. The origin of RIPA was categorized into four patterns according to the inclination of the origin on transverse sections of MDCT. RIPA that originated at the right renal artery and showed an upward course perpendicular to the scan section of MDCT were most clearly visualized at the origin. In addition, RIPA could be observed in an optional direction on the workstation. Pre-angiographic visualization of the origin of RIPA may save angiographic time, curtail contrast medium, and reduce radiation exposure.
    抄録全体を表示
    PDF形式でダウンロード (214K)
第34回秋季学術大会　特別講演
教育講座―技師が書く技師のための読影講座―
基礎講座―検査を実施する上で知っておきたい画像処理技術―
臨床技術講座
連載読み物―医療の周りの法律について（5）―
学術交流委員会報告
グループ探訪
JIRA トピックス
    • |<
    • <
    • 1
    • >
    • >|
feedback
 Top