Acta Medica Okayama 1 2002 Detection of defects at BGA solder joints by using X-ray imaging 191 196 EN Tetsuhiro Sumimoto Toshinori Maruyama Yoshiharu Azuma Sachiko Goto Munehiro Mondou Noboru Furukawa Saburo Okada <p>In the surface mount technology, a ball grid array (BGA) has been used in the production of PC boards. This paper deals with the detection of defects at BGA solder joints in PC boards by using X-ray imaging. Types of defects at BGA solder joints are solder bridge, missing connection, solder voids, open connection and misregistration of parts. The problems of image analysis for the detection of defects at BGA solder joints are the detection accuracy and image processing time according to the speed of the production line. To get the design data for the development of the inspection system used in the surface mount process, it is important to develop image analysis techniques based on X-ray image data. At the first step of our study, we attempt to detect the characteristics of the solder bridges based on the image analysis technique. </p> No potential conflict of interest relevant to this article was reported.

Acta Medica Okayama 2 2003 Development of image analysis for detection of defects of BGA by using X-ray images 1131 1136 EN Tetsuhiro Sumimoto Toshinori Maruyama Yoshiharu Azuma Sachiko Goto Munehiro Mondou Noboru Furukawa Saburo Okada <p>In the surface mount technology, Ball Grid Array (BGA) has been used in a production of PC boards, because of their excellent characters such as high density of the lead pin pitch, better lead rigidity and self-alignment during re-flow processing. This paper deals with the development of image analysis for the detection of defects at BGA solder joints in PC boards by using X-ray images. In the conventional IC boards, it is possible to detect defects of solder joints by visual inspection, because the lead of IC package is set on its outside. However, we can't detect visually defects at BGA solder joints, because they are hidden under the IC package. In a production line, the inspection of BGA in PC boards depends on the function test of electric circuits in the final process. To improve a cost performance and the reliability of PC boards, an inspection of BGA is required in the surface mount process. Types of defects at BGA solder joints are solder bridge, missing connection, solder voids, open connection and miss-registration of parts. As we can find mostly solder bridge in these defects, we pick up this to detect solder bridge in a production line. The problems of image analysis for the detection of defects at BGA solder joints are the detection accuracy and image processing time according to a line speed of production. To get design data for the development of the inspection system, which can be used easily in the surface mount process, it is important to develop image analysis techniques based on X-ray image data. At the first step of our study, we attempt to detect the characteristic of the solder bridges based on an image analysis. </p> No potential conflict of interest relevant to this article was reported.

岡山大学環境管理センター Acta Medica Okayama 0917-1533 17 1995 診療用X線検査における撮影条件と被曝線量の関係について―特に腹部検査を対象して― 63 70 EN Yoshitada Nakagiri Yoshiharu Azuma Koichi Sibuya Sachiko Goto Toshinori Maruyama Katsuhiko Sugita Masayo Sonoyama Yasuki Morioka Keiji Inamura Seiji Tahara Hirofumi Uno Shigefumi Kadohisa Tatsuya Inoue Yoshio Hiraki Patient dose is important consideration in the radiological examination and our environment regarding radiation. Many studies have been published about patient dose, but those data were classified by each organ or tissue. Actuarially, patient dose should be checked by each examined part of patient and each exposure equipment. In this paper, we measured absorbed dose at the depth of 0-200mm with the Mix-DP phantom. The phantom is made by tissue equivalent meterial and is designed to similitude abdominal part. Percentage Depth Dose (PDD) was calculated from these doses. Three single-phase generators and three three-phases generators were used in this measurement. These measurements were analyzed by each equipment, and consequently the clear difference of PDD between the exposure equipments was not found. As the result, we can estimate patient dose at a random depth by using PDD. Furthermore, we can easily know patient dose from the tube-voltage and current time product by the calculation including PDD.These data are very useful to manager patient dose on radiological diagnosis. No potential conflict of interest relevant to this article was reported.

岡山大学環境管理センター Acta Medica Okayama 0917-1533 20 1998 腹部単純X線撮影時の被曝線量―岡山県下の病院の現況― 17 21 EN Yoshitada Nakagiri Yoshiharu Azuma Toshinori Maruyama Koichi Sibuya Sachiko Goto Katsuhiko Sugita Yasuki Morioka Sigefumi Kadohisa Tatsuya Inoue Yoshio Hiraki In 1995, we have published a paper about the basic data on the relation between X-ray exposure equipment and patient dose in Vol. 17 of the Journal "Environment Research and Control". In this time, we questioned hospitals in Okayama Prefecture about exposure equipments of abdomen. And we compared each hospital's exposure equipments with the basic data, calculated each patient dose, then we studied that differences. Various imaging system, for example; screen/film or imaging plate has been used at each hospitals, so that exposure are various and patient doses are very different. The exposure equipment decide that the X-ray photograph is good or bad, so we cannot treat it easily. But we think that we have to try to take X-ray photographs which are suit the purpose of diagnosis which as a small patient dose as possible. No potential conflict of interest relevant to this article was reported.

岡山大学医療技術短期大学部 Acta Medica Okayama 0917-4494 8 1 1997 電子線治療における骨の線量分布に対する影響に関する検討 37 42 EN Yoshitada Nakagiri Keiji Inamura Seiji Tahara Hirofumi Uno Yoshiharu Azuma Koichi Sibuya Sachiko Goto Toshinori Maruyama Yasuki Morioka Katsuyosi Sakae Mitsuhiro Takemoto Katsuhiko Sugita Yoshio Hiraki 10.18926/15282 電子線治療は,体表面またはその近傍に発生する悪性腫瘍の治療にしばしば用いられる治療法である｡電子線はエネルギーに対応した飛程を持っており,飛程を越えると急激に線量は減少する。この性質は腫瘍に一定の線量を照射し,腫瘍後方に存在する決定臓器を保護することができるので,病巣を選択的 に治療するのに好都合である｡しかし,照射野内に人体軌部組織より密度の違う物質が存在する場合,散乱,吸収の影響が大きく,電子線線量分布は乱れたものとなる｡今回,人体内にある骨を想定してVolumeの違う骨Phantomを使 用して影響を調べたところ,骨幅によって骨後方および断端に線量の乱れが生じることがわかった｡すなわち,骨の中央ではある程度後方に距離が離れると,線量は大きく減少する現象が見られた。また,横方向の線量分布は骨断端近くで一旦線量の減少が見られ,断端を離れると急激に増加する｡したがって,実際の臨床において,Target Volume近くに骨が存在する場合は総線量の決定に際して注意が必要である｡ No potential conflict of interest relevant to this article was reported.

岡山大学医療技術短期大学部 Acta Medica Okayama 0917-4494 8 2 1998 The Influence of Film Processing Temperature and Time on Mammographic film Characteristics 121 129 EN Toshinori Maruyama Sachiko Goto Yoshiharu Azuma Yoshitada Nakagiri Koichi Shibuya Katsuhiko Sugita Tomoyuki Takeuchi Mitsugi Honda Akira Yoshida 10.18926/15261 The influence for developing temperature and processing time within film processing conditions was investigated using four mammographic films, Konica New CM, Fuji UM-MA HC, Kodak Min-R M and Kodak EB/RA (for rapid system). And Fuji UR-2, a double-emulsion film, was used as a control. Those sensitometric strips exposed by a sensitometer were processed in the different combinations of developing temperatures ranging from 28 to 36℃, processing times from 45 to 210 sec. Average gradient, relative speed and base plus fog obtained from the measured film characteristic curves were evaluated for the different developing temperatures and times. Fuji UR-2 was scarcely affected and mammographic films were greatly affected in the different combinations without an increase in base plus fog except EB/RA. In New CM, UM-MA HC and Min-R M, the average gradients and the relative speeds increased as the developing temperature was higher and the developing time was longer, but the increases were limit on the combination of 36℃ and 210 sec in New CM and UM-MA HC. In EB/RA, the average gradients were almost constant and the relative speeds increased slightly like the double-emulsion film. These results suggested that it would be possible to contribute to dose reduction and advancement of contrast in New CM, UM-MA HC and Min-R M by changing these processing parameters. No potential conflict of interest relevant to this article was reported.

岡山大学医療技術短期大学部 Acta Medica Okayama 0917-4494 8 2 1998 自作ファントムによる硫酸バリウム製剤の濃度及び混合比の検討 113 119 EN Koichi Shibuya Tomonori Miyahara Kazuyuki Sumi Yasuhiko Okura Koichi Miyake Kazuhiro Okuda Nobuyoshi Tandani Yoshiharu Azuma Sachiko Goto Toshinori Maruyama Yoshitada Nakagiri Katsuhiko Sugita Yoshio Hiraki 10.18926/15260 胃�]線検査に造影剤として用いられる硫酸バリウム懸濁液の濃度を,簡便に,客観的に決定する目的で,歯科用アルギン酸塩印象材を用いて,コインの図柄を写しとったファントムを制作した｡これを使って二種類の硫酸バリウム製剤の適正濃度(PD)を調べた結果,BARITOP PとBARICON MEALを単体,若くは混合した場合には,おおよそ,PD(W/V%)=0.75C+165(ただし,CはBARICON MEALの混合比(%))となった｡また,BARICON MEALはコントラストが高く,精密検査に有利だと考えられ,BARITOP PとBARICON MEALを混合すると濃度の許容範囲が広がるため,通常の検査に都合がよいと考えられた｡更に,このファントムは簡便に作成することができ,しかも,硫酸バリウム懸濁 液との親和性も良いことから,硫酸バリウム製剤や�]線TV装置の評価,増感紙･フィルム系の評価等にも応用できると考えられた｡ No potential conflict of interest relevant to this article was reported.

岡山大学医療技術短期大学部 Acta Medica Okayama 0917-4494 9 2 1999 Improvement of image quality on mammographic screen-film system by extended-cycle process 83 90 EN Sachiko Goto Toshinori Maruyama Yoshiharu Azuma Yoshitada Nakagiri Yoshihiro Takeda Katsuhiko Sugita Fumie Kimura Shigefumi Kadohisa 10.18926/15252 Extended-cycle process is the term used for a processor in which the processing time has been prolonged usually to approximate 210 seconds. It has been known that the extended-cycle process of some single-emulsion films as used for mammography may enhance film contrast and increase film speed. So the speed was increased in lower speed and higher resolution system than conventional systems by means of using the extended-cycle process in this paper. We investigated how much the resolution of the system was kept. A single screen-single emulsion combination, Konica M-100/CM-H was employed as a low speed and high resolution system. This film after exposure was processed in the different combinations of developing temperatures, 30, 32 and 34℃, and processing time of 210 seconds. On the other hand, Konica M-200/CM-H was employed as a high speed system. This film was processed in the standard-cycle processing (34℃, 90 seconds). Those systems were compared on contrast, speed, screen-film blur and noise by a characteristic curve, MTF (modulation transfer function) and WS (wiener spectrum). Furthermore, the RMI 165 phantom was used to evaluate visibility of mammographic details of these systems. As a result, in the extended-cycle process at the developing temperatures of 32 or 34°C and processing time of 210 seconds for M-100/CM-H, it was possible to increase the speed as much as the higher speed system, M-200/CM-H. Then the contrast, the MTF and the visibility were also improved as compared to the higher speed system. Furthermore patient dose could be reduced at the developing temperature of 34℃ and processing time of 210 seconds in M-100/CM-H. No potential conflict of interest relevant to this article was reported.

岡山大学医学部保健学科 Acta Medica Okayama 1345-0948 14 1 2003 線量測定用GAFCHROMIC XR TYPE Tの特性 23 29 EN Mariko Kubotsu Yoshitada Nakagiri Ayako Ujifuku Yukiko Taniguchi Miho Hachiya Yoshiharu Azuma Sachiko Goto Toshinori Maruyama Hideki Aoyama Seiji Tahara Keiji Inamura Toshimitsu Watanabe Katsuhiko Sugita 10.18926/15204 医療の高度化に伴い,近年では長時間の�]線透視を行うInterventional Radiology(IVR)手技が頻繁に行われ,副作用としての難治性放射線皮膚障害例の報告が増加している｡確定的影響である放射線皮膚障害はしきい値を超えると発症し,線量に依存して障害の程度が重篤となるため,患者被曝線量の測定が重要である｡しかし,IVRでは照射部位が多彩で,焦点-皮膚間距離が不安定なため,その測定方法は確立されていない｡本研究では,近年IVR等低エネルギー線量測定用フイルムとして開発されたCAFCHROMIC XR TYPE T について性能評価を行い,患者皮膚入射面の被曝線量測定への応用の可能性について検討した｡その結果,線量特性,線質特性,ネット値の安定性に良好な特性を示し,臨床に使用可能であったので報告する｡ No potential conflict of interest relevant to this article was reported.

岡山医学会 Acta Medica Okayama 0030-1558 107 1-6 1995 胃X線検査用影剤のコントラスト特性と撮影タイミングについて 1 6 EN Koichi Shibuya Yoshitada Nakagiri Yoshiharu Azuma Katsuhiko Sugita takao Kobashi Yasuhiko Okura Nobuyoshi Tandani Yasutaka Mikami Yoshio Hiraki We studied the relationship between the contrast characteristics of barium suspension and timing of exposure. We poured several kinds of barium preparations on the phantom manufactured by ourselves, and took X-ray pictures continuously by a DSA system. We analyzed each of the characteris-tics of the contrast. The time which was reguired for the contrast to reach the peak (Contrast Peak Time ; CPT) was unrelated with the kind of barium preparations used. It depended on the viscosity of the contrast media and the angle of the phantom. Viscosity was correlated with CPT. CPT was 3 to 6 seconds at an angle of 15 degrees, and 1.5 to 4 seconds at an angle of 30 degrees. We can refer to these findings to decide the density of barium suspension and to get timely exposure. No potential conflict of interest relevant to this article was reported.

岡山大学医療技術短期大学部 Acta Medica Okayama 0917-4494 5 1995 清涼飲料入り胃X線検査用造影剤 111 114 EN Koichi Shibuya Yoshitada Nakagiri Yoshiharu Azuma Sachiko Goto Katsuhiko Sugita Yasuhiko Okura Nobuyoshi Tandani Eitaro Nobuhara Yasutaka Mikami 10.18926/11936 胃検診の受診者を増やし、検査を円滑に行う上で、造影剤である硫酸バリウム懸濁液の飲みにくさが障害の一つとなっている。これを改善する試みとして、懸濁液に市販の粉末清涼飲料を混入し検討したところ72.1％の人から通常のものよりも飲みやすいという回答を得た。今後、臨床的な検討を加えながら、さらに創意工夫していく必要がある。 No potential conflict of interest relevant to this article was reported.

岡山大学医療技術短期大学部 Acta Medica Okayama 0917-4494 5 1995 非対称増感紙フィルム系の粒状性 105 110 EN Mitsugi Honda Akira Yoshida Nobue Nakamura Seiichi Mimura Sigefumi Kadohisa Yasutaka Mikami Yoshiharu Azuma Tomoyuki Takeuchi Katsuhiko Sugita Yoshio Hiraki 10.18926/11934 非対称増感紙フィルム系について、両面乳剤フィルムのウィナースペクトル測定に及ぼす影響を検討した。濃度0.5〜2.5のノイズ試料のフロント乳剤、バック乳剤、支持体層それぞれで測定したスペクトルの和と、両面同時に測定した全スペクトルとを比較した。その結果、全ウィナースペクトルの値は、フロント乳剤、バック乳剤の和より高くなった。また、試料濃度が高いほど、その差は大きくなった。これらは、マイクロデンシトメータの光学系の配置と両面乳剤フィルムの構造に起因している。したがって、非対称システムのようにフィルムの前面と後面で特性を分けて考える場合、注意を要する。 No potential conflict of interest relevant to this article was reported.

岡山大学医療技術短期大学部 Acta Medica Okayama 0917-4494 5 1995 リニアック（東芝LMR-15A）の故障の統計と分析 99 103 EN Yoshitada Nakagiri Yasutaka Mikami Yoshiharu Azuma Koichi Sibuya Sachiko Goto Keiji Inamura Seiji Tahara Hirofumi Uno Katsuhiko Sugita Yoshio Hiraki 10.18926/11931 放射線治療の成否は厳密に設定されたTarget Volumeに如何に正確な線量を照射するかによって決まる。治療術式の過程において、最も大きな誤差を生む要因は照射機器である。誤差の少ない治療を目指す第一歩は機器を正確に作動させることであり、日常からの保守点検および整備が必要である。今回、岡山大学附属病院で1976年から1991年までに使用されたリニアックについて、その故障状況を集計し、部位別故障件数、管球の寿命、稼動率などを分析検討した。その結果、故障件数では設置され稼動を始めた1976年、装置の老朽化が進んだ1990、1991年に多かった。部位別集計では加速部に圧倒的に多く、次いで照射口、高圧部の順であった。稼動率は設置年および1987年を除いてはいずれも96％以上とよい結果であった。この結果は全国に稼動している同型の装置の保守点検に役立つものと考える。 No potential conflict of interest relevant to this article was reported.

岡山大学医療技術短期大学部 Acta Medica Okayama 0917-4494 5 1995 学部シラバス作成に関する教官の意見 1 8 EN Takeo Ohta Yasuaki Shimoishi Yoshiharu Azuma Hiroshi Endo Yuka Okazaki 10.18926/11900 シラバスは、その内容も含めて、まだ教官にも、学生にもなじみのない言葉である。著者らは、1994年、初めてのシラバス（講義要覧）を刊行した。このシラバスの中では、1人もしくは数人の教官によって、１教科・１学期分の講義の概要が各1ページの中に記載され、その枠組みは、基本的事項以外に、抗議の目標、授業計画、授業計画、教科書、参考書、授業の進め方、評価の方法、教官のメッセージから成るものであった。このシラバス作成に参加した専任教官45人及び非常勤教官107人、計153人に対し、調査表によってシラバス作成に関する意見を求めた結果、117人（77.0％）の教官が解答を寄せた。その結果は次のようなものであった。1.今回の作成計画以前にシラバスについて認識があった者は44.5％であった。しかし、シラバスの今後の発行に関しては94.9％の者が賛成であった。今回の枠組みについてはほとんどの者が肯定的であった。2.学生による授業評価については、約半数（52.7％）が賛成であるが、時期尚早とする者が41.8％いた。 No potential conflict of interest relevant to this article was reported.

岡山大学医療技術短期大学部 Acta Medica Okayama 0917-4494 4 1994 画像処理による顎関節の解析 ―下顎頭位の判別― 75 82 EN Yoshiharu Azuma Sachiko Gotou Yoshitada Nakagiri Nobue Nakamura Kouichi Shibuya Toshiharu Yamada Katsuhiko Sugita Yasutaka Mikami Yoshio Hiraki 10.18926/11886 Tomography is clinically useful in the diagnosis of the temporomandibular joint (TMJ) syndrome. The TMJ is formed by the condyle and the glenoid fossa, and there exists TMJ space between them. Image processing was employed in the present study, and the reference points of the condyle and the glenoid fossa were determined from the tomogram. Subsequently, the TMJ space was measured automatically in the image analysis. The TMJs of 98 patients were examined practically and the characteristics of each result were studied. There is a possibility of discriminating an abnormal condylar position from a normal one by making use of the TMJ space and the distance between two reference points. No potential conflict of interest relevant to this article was reported.

岡山大学医療技術短期大学部 Acta Medica Okayama 0917-4494 4 1994 X線撮影領域における線量測定　―撮影条件と臓器の被曝― 69 73 EN Yoshitada Nakagiri Sachiko Goto Yasutaka Mikami Yoshiharu Azuma Koichi Sibuya Keiji Inamura Seiji Tahara Hirohumi Uno Yoshiaki Takata Nobuyoshi Tandani Toshiharu Yamada Katsuhiko Sugita Yoshio Hiraki 10.18926/11878 Utilization of radiation in medical treatment is increasing more and more ; consequently, It becomes more important to estimate exposure dose correctly. Altough there are many reports about exposue dose for patients, most of them merely describe the results of the measurements by parts of the body. Exposure dose differs with equipment, instruments, screen-firm system, contition of radiography, and so on. This paper describes the relation between skin dose and contitions of radiography, and also shows the result of measurement of "TPR" which needs to know the absorbed dose of each organ. No potential conflict of interest relevant to this article was reported.

岡山大学医療技術短期大学部 Acta Medica Okayama 0917-4494 4 1994 高濃度低粘性硫酸バリウム製剤の評価 57 60 EN Koichi Shibuya Takao Kobashi Mitsuo Ogasawara Nobuyoshi Tandani Yoshitada Nakagiri Yoshiharu Azuma Katsuhiko Sugita 10.18926/11874 In this paper we compared the balium preparations having high density and low viscosity (BP-HDLV) with those currently in use. We adopted the stomaches of pigs and the new phantom manufactured by ourselves. We especialy noted the quality of the contrast. The results indicate that BP-HDLV do not always make high contrast. The contrast is related to fluidity besides density. The fluidity of BP-HDLV should be improved. In adition, it costs much to increase content of balium. Therefore, we can not find out positive significance to use these BP-HDLV. No potential conflict of interest relevant to this article was reported.

岡山大学医療技術短期大学部 Acta Medica Okayama 0917-4494 3 1993 電子線エネルギー低減におけるX線混入率の検討 ―スキャタリングホイルの材質について― 13 18 EN Yoshitada Nakagiri Seiiti Mimura Keiji Inamura Seiji Tahara Hideaki Miyake Yoshiharu Azuma Tomomi Egusa Yasutaka Mikami Yoshio Hiraki Toshiharu Yamada Katsuhiko Sugita 10.18926/11820 The total skin electron beam therapy has been one of the clinical treatment for peripherally T-cell lymphoma; Mycosis fungoides, adult T-cell lymphoma, and so on. The crucial points in this treatment are not only having an optimum energy level of electron beam for a target volume (a tissue) but also keeping the photon back ground low. It is not easy to regulate those points by the control panel, however, for the equipment that is conventinally used for electron beam, theoretically, is to exchange lead (Pb), which is ordinarily used, to a low atomic number material as a scattering foil. We examined several different kinds and / or various thickness as a scattering foil material that can make the electron beam lower without an increase of the contaminant as X-ray. We hereby reported the results, and strongly suggested the following two materials in use; acrylic plate, carbon board, and so on, which are easily available and worked, would be practically useful for the total skin electron beam therapy. No potential conflict of interest relevant to this article was reported.

岡山大学医療技術短期大学部 Acta Medica Okayama 0917-4494 2 1992 CRTモニタの解像特性 81 88 EN Tomoyuki Takeuchi Akira Yoshida Yoshiharu Azuma Katsuhiko Sugita Nobue Nakamura Kanji Kishi Yoshio Hiraki 10.18926/11808 We have developed a new technique for measuring the modulation transfer function (MTF) of a cathode ray tube (CRT) monitor. The "nominal" MTF was measured by displaying a line image of a width of one pixel on the CRT monitor using the pattern generator. We also measured the effective pixel width. In order to obtain the "actual" MTF, the nominal MTF was divided by the sinc function which is the Fourier transform of the effective pixel width. The results indicate that the corrected MTF　converges to the constant value as the effective pixel width is narrower. Thus, the actual MTFs were determined and compared in the horizontal direction for two CRT monitors. No potential conflict of interest relevant to this article was reported.

岡山大学医療技術短期大学部 Acta Medica Okayama 0917-4494 2 1992 撮影X線領域での線量分布 63 71 EN Hideaki Miyake Keiji Inamura Yoshitada Nakagiri Shigefumi Kadohisa Yasutaka Mikami Yoshiharu Azuma Toshiharu Yamada Katsuhiko Sugita Yoshio Hiraki 10.18926/11805 Exposure dose has been indicated by surface dose or transit dose, but they could not indicate dose distributions inside the body. Modulex as the radiation therapy planning system was used for dose distributions at standard diagnostic X-ray energy. X-ray is low energy X-ray at standard diagnostic radiography, so alterations of the energy and the scattering dose distribution by absorbers are quite different from those at high energy X-rays. Mix-DP was put to the homogeneous tissue use, then Bone equivalent phantom or Lung equivalent phanton was put to the inhomogeneous tissue use. Density correction factors for inhomogeneous phantoms were gotten by the calculation of the water equivalent thickness. In Bone the inhomogeneous correction depended strongly on the bone thickness. In Lung it was in need of one density correction factor and the scattering correction method for the decrease of the back scattering. The calculated dose distributions by Modulex agreed with measured data when each correction was carried out, and it was indicated that those data apply to inclinical situations. No potential conflict of interest relevant to this article was reported.

岡山大学医療技術短期大学部 Acta Medica Okayama 0917-4494 7 1 1996 学部シラバスに関する学生の意見 29 33 EN Takeo Ohta Yasuaki Shimoishi Yoshiharu Azuma Mituko Ichimura Hiroshi Endo Yuka Okazaki 10.18926/11770 1995年4月に初めての本学のシラバス（講義要覧）が発行され、学生に配布された。本報は約1年後の1996年2月の試験期間中にシラバスに対する学生の意見を問うために行われたアンケート調査の結果をまとめたものである。回答を寄せた学生は435人で、在籍学生の89.0％であった。よく利用したとする学生は18.2％、数回利用したとする学生は67.6％であった。学生の使用目的はテストの準備や履修科目の決定のためであった。以上のことから、現在のシラバスは学生が日常的により活用するためにはさらに教師が改善、工夫する必要があると思われた。 No potential conflict of interest relevant to this article was reported.

岡山大学医療技術短期大学部 Acta Medica Okayama 0917-4494 7 1 1996 ビームフラットネスアナライザ（7000型 THEBES）の基礎的性能の検討 23 27 EN Yoshitada Nakagiri Nobuhiro Oguri Toshinori Maruyama Yoshihiro Okawa Hiroyuki Wakasa Isao Nagaya Yoshiharu Azuma Koichi Shibuya Sachiko Goto Yasutaka Mikami Keiji Inamura Yasuki Morioka Katsuhiko Sugita Yoshio Hiraki 10.18926/11766 癌の有力な治療法の1つである放射線治療はシステム全体の許容誤差が±5％と、正確な治療が要求されている。正確な線量を正確な場所に照射されなければならない。そのためには日頃から照射装置のQuality Control が重要である。Beam平坦度の測定はその中でも、重要な項目で1／6月の測定頻度が勧告されている。今回、市販のBeam Flatness Analyzer (7000型 THEBES) を使用する機会を得たので、その基礎的性能であるChamber 相互の感度のちがい、測定値の再現性、識別可能な最小線量について実験を行った。各項目とも誤差が非常に少なく、日常の使用に際してそのデータは十分信頼できるものであることがわかった。 No potential conflict of interest relevant to this article was reported.

岡山大学医療技術短期大学部 Acta Medica Okayama 0917-4494 1 1991 ブートストラップセンシトメトリー用ステップウェッジの開発 19 27 EN Akira Yoshida Toshimi Kobashi Yoshihiro Ohkawa Yasutaka Mikami Yoshio Hiraki Yoshiharu Azuma Toshiharu Yamada Katsuhiko Sugita 10.18926/11755 A new stepwedge has been developed for bootstrap sensitometry, which is used for determining the characteristic curve of radiographic screen/film systems. Since each step of the stepwedge is separated by the lead septum, flare generated under one step will not penetrate the region of another step. The metal of the stepwedge can be changed with various materials. Characteristic curves obtained with new stepwedge bootstrap (NSB) and conventional stepwedge bootstrap (CSB) techniques were compared with those obtained for screen/film systems with inverse sqare sensitometry. The inverse square method was used as the reference standard for accuracy. The NSB method provided characteristic curves that agreed well with those obtained using the inverse square method. The slope of the curve in the CSB method was lower than that in the inverse square or NBS method, because of scatter radiation. The shape of the characteristic curve from the NSB method did not vary with the materials of step metals (aluminum and copper). The cumulative error involved when using the bootstrap method is also discussed. No potential conflict of interest relevant to this article was reported.

岡山大学医療技術短期大学部 Acta Medica Okayama 0917-4494 6 1996 清涼飲料入り胃X線検査用造影剤の臨床応用 15 21 EN Koichi Shibuya Yoshitada Nakagiri Yoshiharu Azuma Sachiko Goto Toshinori Maruyama Katsuhiko Sugita Yasuhiko Okura Koichi Natsukawa Nobuyoshi Tandani Eitaro Nobuhara Yasuki Morioka Yoshihiro Takeda Yoshio Hiraki 10.18926/11735 胃X線検査の被験者を増やし、検査を円滑に行う上で造影剤である硫酸バリウム懸濁液の飲みにくさが障害の一つとなっている。これを改善する目的で、懸濁液に市販の粉末清涼飲料を混入したところ、64.2％の人が通常のものよりも飲みやすいと答えた。臨床上も造影剤の付着が悪くなったり、胃の蠕動を促進する等の問題は生じず、有用であると考えられた。 No potential conflict of interest relevant to this article was reported.

岡山大学医療技術短期大学部 Acta Medica Okayama 0917-4494 6 1996 増感紙フィルム系の物理特性 ―胸部用新システム― 7 13 EN Sachiko Goto Akira Yoshida Nobue Nakamura Toshinori Maruyama Yoshiharu Azuma Koichi Shibuya Yoshitada Nakagiri Katsuhiko Sugita Mitsugi Honda 10.18926/11733 胸部専用の新しい増感紙／フィルムシステムについて物理的画質特性を測定し、従来のシステムと比較を行った。測定した新システムは、日本コダックのインサイトシステムからHC/IT-1、富士メディカルシステムのADシステムからHG-M/UR-1、コニカのEXシステムからXG-S/ES-C である。従来のシステムとして富士メディカルシステムのHR-4/Super HR-S を使用した。その結果、新システムは22〜73％感度は高く、特性曲線においては低濃度部を持ち上げ、最大コントラストは高濃度側にシフトしていた。空間周波数2cycles/mmで相対鮮鋭度を比較すると、新システムが10〜30％程度の低下となっていた。ノイズは、濃度1.0で新システムが35〜46％の減少となった。以上より、新システムは、縦隔部の濃度を上げ、粒状性の改善を重視した設計となっていることが分かった。 No potential conflict of interest relevant to this article was reported.

岡山大学医学部保健学科 Acta Medica Okayama 1345-0948 10 2 2000 マンモグラフィ用増感紙／フィルムシステムの特性曲線における空気減弱の影響 91 98 EN Toshinori Maruyama Sachiko Goto Yoshiharu Azuma Yoshitada Nakagiri Koichi Shibuya Katsuhiko Sugita 10.18926/11721 マンモグラフィ専用装置を使用して，距離法で低エネルギー領域のX線におけるマンモグラフィ用増感紙／フィルムシステムの特性曲線を得るためには，空気滅弱の影響を考慮する必要がある。その影響について，実効エネルギーから空気減弱分を補正，照射線量測定による補正，Bednarek法を応用した新距離法の3種類の方法を使って検討した。さらに，一般撮影装置でも，マンモ用システムに対して距離法で特性曲線を作成し，エネルギ ーの変化による影響についても検討した。その結果，3方法の特性曲線およびグラディエント曲線は，新距離法が高濃度域でわずかにずれるもののほぼ一致した。新距離法に対する平均階調度，最大階調度の最大誤差は，2.7％，0.2％であり，一般撮影用装置の距離法と3方法との間では，一般撮影用装置の距離法に対して最大誤差は2.7％，1.5％であった。以上のことから，エネルギーの変化による特性曲線への影響はほとんどなく，低エネルギー領域での特性曲線は空気特配の補正を行うことのみで得られると考えられる。 No potential conflict of interest relevant to this article was reported.

岡山大学医学部保健学科 Acta Medica Okayama 1345-0948 10 2 2000 Breast dosimetry system in screen/film mammography 99 106 EN Sachiko Goto Yoshiharu Azuma Toshinori Maruyama Yoshitada Nakagiri Yoshihiro Takeda Katsuhiko Sugita Shigefumi Kadohisa 10.18926/11714 The average glandular dose to glandular tissue m mammography is generally assumed to be a function of beam quality (HVL), x-ray tube target material, tube voltage, breast thickness, breast composition and, to a lesser extent, x-ray tube voltage waveform. The average glandular dose is generally determined from published tables with knowledge of the above function. Tables for a high frequency x-ray generator are not yet published. In our study, the lookup tables for the average glandular dose were made at 28 kV (high frequency x-ray generator), employing a breast simulating tissue (0-100% adipose tissue, 0-100% glandular tissue) phantom for an Mo target - Mo filter source assembly. We tried to estimate breast composition from x-ray mammograms by digital image processing techniques, also using the simulating tissue phantom. Then the system that automatically calculates the average glandular dose from digitized clinical x-ray mammograms was built. It is considered that this system can contribute to objective evaluation of the average glandular dose. No potential conflict of interest relevant to this article was reported.

岡山大学医学部保健学科 Acta Medica Okayama 1345-0948 11 2 2001 股関節X線撮影時の女性生殖腺防護についての検討 59 64 EN Yoshitada Nakagiri Toshinori Maruyama Sachiko Goto Yoshiharu Azuma Koichi Shibuya Eri Tamura Eriko Tanimoto Fumiko Torii Yoshihiro Takeda Katsuhiko Sugita 10.18926/11690 幼小児を含めた若年者の股関節X線撮影検査においては鉛板などで生殖腺を防護して行うのが通常である。男性の場合は生殖腺は体外に露出しているので，それを鉛板で包むようにすればある程度目的は達成される。しかし，女性の場合，生殖腺は骨盤腔内に存在するため，卵巣及び子宮を防護でき診断目的領域にかからないように鉛板を成形し，腹壁上に置いて撮影する。X斬写真上ではグリッドで散乱線を除去しているため，鉛板の陰影がくっきりと撮影され，生殖腺は完全に防護されているように見える。しかし，体内では散乱線によるかなりの被曝があるものと考えられる。そこで今回，鉛板下の散乱線量を鉛板幅及び電圧を変化させ，ファントム内各深さの散乱線量を測定した。その結果，鉛板下の散乱線量が相当量認められ，その量は深さ3〜4cmでピークを形成した。鉛板幅による変化は幅が狭いほど線量は大きくなり，電圧による変化は60kVと80kVを比べると80kVの方が多くなった。これを鉛板なしの場合と比較すると，ファントム内意さが増すにしたがい増大した。したがって，臨床において鉛板がずれて再撮影をすることのないよう細心の注意が必要であると考えられた。 No potential conflict of interest relevant to this article was reported.

Acta Medica Okayama 1998 顎関節におけるデｨジタル画像解析と診断支援に関する研究 EN No potential conflict of interest relevant to this article was reported.