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1. Couch height–based patient setup for abdominal radiation therapy

Author

Kinji Nishiyama, S. Oohira, Yoshihiro Ueda, Masahiko Koizumi, Masaaki Takashina, Masaru Isono, T. Katsutomo, Masayoshi Miyazaki, T. Teruki, and Kiyoto Kawanabe

Subjects
Male, Cancer Research, medicine.medical_specialty, Radiography, medicine.medical_treatment, Patient positioning, Patient Positioning, Standard deviation, 030218 nuclear medicine & medical imaging, Computed tomographic, 03 medical and health sciences, 0302 clinical medicine, Humans, Medicine, Radiology, Nuclear Medicine and imaging, Skin marks, Aged, Aged, 80 and over, Radiation, Radiological and Ultrasound Technology, No action level, business.industry, Isocenter, Middle Aged, Pancreatic Neoplasms, Radiation therapy, Oncology, 030220 oncology & carcinogenesis, Female, Radiology, Radiotherapy, Conformal, Nuclear medicine, business
Abstract

There are 2 methods commonly used for patient positioning in the anterior-posterior (A-P) direction: one is the skin mark patient setup method (SMPS) and the other is the couch height-based patient setup method (CHPS). This study compared the setup accuracy of these 2 methods for abdominal radiation therapy. The enrollment for this study comprised 23 patients with pancreatic cancer. For treatments (539 sessions), patients were set up by using isocenter skin marks and thereafter treatment couch was shifted so that the distance between the isocenter and the upper side of the treatment couch was equal to that indicated on the computed tomographic (CT) image. Setup deviation in the A-P direction for CHPS was measured by matching the spine of the digitally reconstructed radiograph (DRR) of a lateral beam at simulation with that of the corresponding time-integrated electronic portal image. For SMPS with no correction (SMPS/NC), setup deviation was calculated based on the couch-level difference between SMPS and CHPS. SMPS/NC was corrected using 2 off-line correction protocols: no action level (SMPS/NAL) and extended NAL (SMPS/eNAL) protocols. Margins to compensate for deviations were calculated using the Stroom formula. A-P deviation > 5mm was observed in 17% of SMPS/NC, 4% of SMPS/NAL, and 4% of SMPS/eNAL sessions but only in one CHPS session. For SMPS/NC, 7 patients (30%) showed deviations at an increasing rate of > 0.1mm/fraction, but for CHPS, no such trend was observed. The standard deviations (SDs) of systematic error (Σ) were 2.6, 1.4, 0.6, and 0.8mm and the root mean squares of random error (σ) were 2.1, 2.6, 2.7, and 0.9mm for SMPS/NC, SMPS/NAL, SMPS/eNAL, and CHPS, respectively. Margins to compensate for the deviations were wide for SMPS/NC (6.7mm), smaller for SMPS/NAL (4.6mm) and SMPS/eNAL (3.1mm), and smallest for CHPS (2.2mm). Achieving better setup with smaller margins, CHPS appears to be a reproducible method for abdominal patient setup.

Published
2016
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2. The Simulation of the Tumor Control and the Normal Tissue Complications in Accelerated Radiation Therapy for Stage III Non–small Cell Lung Cancer

Author

Y. Anetai, Masayoshi Miyazaki, S. Oohira, S. Inui, Iori Sumida, K. Wada, Yoshihiro Ueda, Kazuhiko Ogawa, Teruki Teshima, Osamu Suzuki, and Masashi Yagi

Subjects
Oncology, Cancer Research, medicine.medical_specialty, Radiation, business.industry, Normal tissue, Tumor control, Stage III Non-Small Cell Lung Cancer, Internal medicine, medicine, Radiology, Nuclear Medicine and imaging, Accelerated Radiation Therapy, business
Published
2017
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3. Planning Study for Esophageal Cancer: A Dosimetric Comparison of Conformal Radiation Therapy, VMAT, and Hybrid-VMAT

Author

Masayoshi Miyazaki, K. Tsujii, S. Oohira, Masaru Isono, S. Inui, Teruki Teshima, Yoshihiro Ueda, and A. Masaoka

Subjects
Cancer Research, medicine.medical_specialty, Radiation, Oncology, business.industry, Planning study, medicine, Conformal radiation therapy, Radiology, Nuclear Medicine and imaging, Radiology, Esophageal cancer, medicine.disease, business
Published
2017
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4. Dose Volume Parameters as Predictors for Radiation-Induced Hypothyroidism After IMRT or VMAT for Head and Neck Squamous Cell Carcinoma: Comparison of the Availability Between Mean Thyroid Dose and Median Thyroid Dose

Author

Noriko Kishi, Koji Konishi, A. Masaoka, Takero Hirata, Kinji Nishiyama, Teruki Teshima, Masayoshi Miyazaki, Y. Imai, Naoyuki Kanayama, Yoshifumi Kawaguchi, and S. Oohira

Subjects
Cancer Research, Radiation, business.industry, Thyroid, Radiation induced, medicine.disease, Head and neck squamous-cell carcinoma, medicine.anatomical_structure, Oncology, Medicine, Radiology, Nuclear Medicine and imaging, business, Nuclear medicine, Volume (compression)
Published
2016
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5. SU-E-T-437: Four-Dimensional Treatment Planning for Lung VMAT-SBRT

Author

Yasuyuki Ueda, M Miyazaki, Masahiko Koizumi, Masaru Isono, A. Masaoka, Teruki Teshima, S. Oohira, Masaaki Takashina, and Misaki Hashimoto

Subjects
Lung, business.industry, Image registration, General Medicine, Intensity (physics), medicine.anatomical_structure, Planned Dose, Maximum intensity projection, Medical imaging, Medicine, Dosimetry, business, Nuclear medicine, Radiation treatment planning
Abstract

Purpose: To assess optimal treatment planning approach of Volumetric Modulated Arc Therapy for lung Stereotactic Body Radiation Therapy (VMAT-SBRT). Methods: Subjects were 10 patients with lung cancer who had undergone 4DCT. The internal target volume (ITV) volume ranged from 2.6 to 16.5cm3 and the tumor motion ranged from 0 to 2cm. From 4DCT, which was binned into 10 respiratory phases, 4 image data sets were created; maximum intensity projection (MIP), average intensity projection (AIP), AIP with the ITV replaced by 0HU (RITV-AIP) and RITV-AIP with the planning target volume (PTV) minus the internal target volume was set to −200 HU (HR-AIP). VMAT-SBRT plans were generated on each image set for a patient. 48Gy was prescribed to 95% of PTV. The plans were recalculated on all phase images of 4DCT and the dose distributions were accumulated using a deformable image registration software MIM Maestro™ as the 4D calculated dose to the gross tumor volume (GTV). The planned dose to the ITV and 4D calculated dose to the GTV were compared. Results: In AIP plan, 10 patients average of all dose parameters (D1%, D_mean, and D99%) discrepancy were 1Gy or smaller. MIP and RITV-AIP plans resulted in having common tendency and larger discrepancy than AIP plan. The 4D dose was lower than the planned dose, and 10 patients average of all dose parameters discrepancy were in range 1.3 to 2.6Gy. HR-AIP plan had the largest discrepancy in our trials. 4D calculated D1%, D_mean, and D99% were resulted in 3.0, 4.1, and 6.1Gy lower than the expected in plan, respectively. Conclusion: For all patients, the dose parameters expected in AIP plan approximated to 4D calculated. Using AIP image set seems optimal treatment planning approach of VMAT-SBRT for a mobile tumor. Funding Support: This work was supported by the Japan Society for the Promotion of Science Core-to-Core program (No. 23003).

Published
2015
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6. SU-E-T-68: A Quality Assurance System with a Web Camera for High Dose Rate Brachytherapy

Author

S. Oohira, Koji Konishi, Yoshifumi Kawaguchi, A Hirose, Masaru Isono, Masayoshi Miyazaki, K Tsujii, Yasuyuki Ueda, and Teruki Teshima

Subjects
business.industry, Computer science, medicine.medical_treatment, Brachytherapy, General Medicine, High-Dose Rate Brachytherapy, Displacement (vector), Dwell time, Software, Position (vector), medicine, Dosimetry, Computer vision, Artificial intelligence, business, Quality assurance
Abstract

Purpose: The purpose of this work was to develop a quality assurance (QA) system for high dose rate (HDR) brachytherapy to verify the absolute position of an 192Ir source in real time and to measure dwell time and position of the source simultaneously with a movie recorded by a web camera. Methods: A web camera was fixed 15 cm above a source position check ruler to monitor and record 30 samples of the source position per second over a range of 8.0 cm, from 1425 mm to 1505 mm. Each frame had a matrix size of 480×640 in the movie. The source position was automatically quantified from the movie using in-house software (built with LabVIEW) that applied a template-matching technique. The source edge detected by the software on each frame was corrected to reduce position errors induced by incident light from an oblique direction. The dwell time was calculated by differential processing to displacement of the source. The performance of this QA system was illustrated by recording simple plans and comparing the measured dwell positions and time with the planned parameters. Results: This QA system allowed verification of the absolute position of the source in real time. The mean difference between automatic and manual detection of the source edge was 0.04 ± 0.04 mm. Absolute position error can be determined within an accuracy of 1.0 mm at dwell points of 1430, 1440, 1450, 1460, 1470, 1480, 1490, and 1500 mm, in three step sizes and dwell time errors, with an accuracy of 0.1% in more than 10.0 sec of planned time. The mean step size error was 0.1 ± 0.1 mm for a step size of 10.0 mm. Conclusion: This QA system provides quick verifications of the dwell position and time, with high accuracy, for HDR brachytherapy. This work was supported by the Japan Society for the Promotion of Science Core-to-Core program (No. 23003).

Published
2015
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9. [Efficacy and safety of sulbactam/cefoperazone for hepato-biliary infections]

Author

N, Shinagawa, S, Takeda, S, Oohira, Y, Yasuda, M, Fujisaki, H, Saito, M, Ueda, K, Mitamura, T, Nishio, M, Itakura, M, Koyama, M, Hirano, R, Ohyama, M, Kako, Y, Amako, K, Okuda, T, Iwasa, A, Sugiyama, S, Takashima, N, Ohswawa, S, Nakaya, M, Yamada, F, Zeze, and J, Ishii

Subjects
Adult, Aged, 80 and over, Male, Adolescent, Cholangitis, Liver Abscess, Cefoperazone, Middle Aged, Klebsiella Infections, Drug Combinations, Treatment Outcome, Sulbactam, Neoplasms, Cholecystitis, Humans, Female, Pseudomonas Infections, Enterococcus, Aged
Abstract

We studied efficacy and safety of sulbactam/cefoperazone (SBT/CPT) in the treatment of biliary tract infections in hospitalized patients at 26 hospitals from February 1993 to March 1995. Secondary to dropout, 273 out of 338 patients entered in the study were evaluated, 127 patients with cholecystitis, 132 patients with cholangitis, and 14 patients with liver abscesses. Of these, 93 patients (34.1% had malignancy as an underlying disease. SBT/CPZ had an efficacy of 79.9% (218 patients; excellent: 52, good: 166), with the efficacy in patients with cholecystitis, cholangitis and liver abscess at 89.0% (113 patients), 77.3% (102 patients and 21.4% (3 patients), respectively. A significant difference (p0.05) was observed in the efficacy rates of patients with (59 patients [63.4%]) and without malignancy (159 patients [88.3%]). A total of 84 strains were isolated from bile specimens of 53 patients, and the major isolates were Escherichia coli, Pseudomonas aeruginosa and Enterococcus spp. Two or more bacterial strains were isolated simultaneously in 20 patients. Mild or moderate side effect (allergic reaction including rash etc.) were noted in 4 patients (1.18%), and laboratory abnormalities (increased GOT, etc.) were in 16 patients (4.71%) out of the total 338 patients. This study clearly demonstrated that SBT/CPZ retains its excellent clinical efficacy and safety profile, throughout its use over the past decade.

Published
1998

11. [Untitled]

Author

Hiromitsu Tamaki, Minoru Ishida, Toru Matsunaga, S Oohira, T Oomoto, and Tetsuji Hori

Subjects
Orthodontics, medicine.anatomical_structure, Otorhinolaryngology, Maxillary sinus, Sex factors, business.industry, Maxillary Fractures, medicine, Fracture (geology), Orbital Fracture, business
Published
1982
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12. General lectures (II)

Author

K. Segawa, S. Nakazawa, N. Koide, K. Imai, N. Matsuo, Y. Yamamoto, M. Shiobara, H. Shimada, K. Kawai, K. Machida, N. Okabe, Y. Hoshi, Y. Koizumi, T. Watanuki, Y. Hiroshima, Y. Matsusaka, K. Katase, Y. Sakuma, N. Matoba, N. Murata, Y. Toyama, S. Murai, A. Nukaga, N. Ishimatsu, Y. Watanabe, M. Abe, Y. Ono, K. Hirai, S. Iwabuchi, K. Suzuki, T. Aoki, K. Masamura, K. Yoshida, J. Ikeuchi, F. Nagao, A. Kobayashi, S. Toriie, M. Nakajima, M. Kohli, K. Ida, M. Masuda, T. Hattori, S. Fujita, T. Tamada, K. Inoue, T. Usui, S. Yamaya, K. Ohtsuka, Y. Shiraki, S. Fujishima, O. Tochikubo, S. Miyamoto, A. Ueda, K. Asano, M. Kunisada, H. Miyake, Y. Fujii, S. Yoshimoto, K. Hiramatsu, S. Nakano, T. Takeda, K. Kitamura, Y. Horiguchi, K. Okada, M. Okada, T. Kuwabara, M. Tanaka, K. Konno, K. Isobe, A. Iwasaki, T. Unoura, M. Matsumoto, T. Yoshida, I. Takahashi, H. Maeda, T. Hayashi, H. Koizumi, M. Iwasaki, K. Takahashi, T. Honda, K. Ariga, S. Mohri, Y. Suga, T. Ono, K. Kobayashi, T. Mizuno, Y. Sameshima, Y. Shiozaki, M. Sasakawa, A. Hiramatsu, K. Ikehara, T. Nagata, K. Tatsumi, M. Aoki, S. Iwasaki, T. Aizawa, K. Kajiwara, K. Sata, S. Omata, K. Imamura, K. Kondo, H. Sajima, Y. Sato, H. Kiryu, S. Mimoto, T. Masuoka, K. Kira, R. Mizumoto, H. Kuratsuka, I. Honjo, Y. Hojo, H. Nakajima, T. Tosaka, O. Arai, N. Kobayashi, N. Obata, S. Ito, T. Takaoka, Y. Uragami, Y. Kitamura, S. Kishi, S. Fujii, H. Okuda, K. Hirano, H. Kano, M. Ogino, Y. Ueda, K. Nishiwaki, N. Iwamura, T. Kamada, T. Suematsu, H. Fusamoto, H. Abe, S. Katayama, K. Yamaguchi, M. Fukuda, T. Ishii, I. Kaito, S. Sato, H. Sasaki, H. Onodera, M. Yamanaka, K. Akagi, S. Miyazaki, M. Okumura, T. Omae, Y. Nakamura, M. Wada, Y. Nakai, S. Inoue, T. Arima, S. Yamasaki, T. Takano, Y. Katsuta, T. Yano, K. Isoda, T. Aramaki, N. Fukuda, T. Ichikawa, H. Okumura, Y. Adachi, R. Inoue, Y. Iwasaki, S. Tanaka, T. Yamamoto, G. Wakisaka, H. Nakaya, S. Takase, F. Ikegami, A. Takada, J. Takeuchi, Y. Kato, A. Funayama, S. Kakumu, S. Okuyama, Y. Taoka, T. Endo, R. Chizuka, T. Yanagida, S. Chizuka, H. Usui, T. Ando, T. Takai, T. Wakahara, M. Kojima, T. Fukazawa, Y. Takahashi, S. Miyamura, T. Urakawa, T. Shima, K. Miyaji, T. Okazaki, S. Kashimura, K. Koyama, H. Yamauchi, Y. Matsuo, Y. Takagi, I. Muto, Y. Owada, T. Otowa, T. Sato, C. Naito, K. Sugawara, T. Nokiba, H. Kido, M. Sasaki, Y. Sugai, G. Nishimura, H. Nanbu, Y. Kamiyama, T. Yamada, Y. Yamaoka, H. Takeda, T. Ohsawa, T. Kamano, T. Mizukami, O. Kitamura, K. Ozawa, H. Takasan, R. Miyasaki, T. Katayama, T. Amakawa, K. Hirose, Y. Furukawa, M. Noguchi, M. Okamoto, H. Maezawa, N. Tanaka, S. Yamada, T. Hisata, C. Hata, J. Sawa, Y. Mituda, S. Oohira, A. Hayasaka, T. Okuyama, S. Fukui, T. Furuichi, S. Yamamitsu, K. Yamauchi, Y. Konishi, S. Maeda, S. Setoyama, S. Otsuji, T. Ibata, H. Niu, A. Ogawa, E. Tujioka, T. Maeda, M. Takewa, T. Matumoto, K. Tamada, A. Maeda, H. Sumita, Y. Iseki, S. Yukawa, Y. Nitta, K. Isida, H. Nomoto, R. Sato, G. Sato, S. Toyokawa, G. Yamamoto, S. Ohtomi, M. Haga, Y. Ueno, R. Endo, T. Yokota, J. Ohsawa, A. Kohno, E. Ohtoshi, H. Yasugi, H. Ichikawa, K. Ando, H. Suzuki, T. Nishiwaki, T. Kishimoto, T. Miki, K. Takeshige, M. Sawada, R. Hidemura, S. Yamamoto, S. Itoh, T. Kashiwagi, M. Kishida, O. Imamura, T. Suematus, K. Sakoda, T. Kawada, Y. Arima, T. Kamimura, M. Takesue, T. Katsuki, H. Akita, Y. Yakeishi, I. Takehisa, K. Miyasato, H. Yoshida, K. Kubota, S. Aoki, S. Suzuki, T. Miyahara, K. Fujiwara, T. Sakai, T. Oda, S. Igarashi, M. Fukuhara, T. Tsujii, T. Tamura, Y. Matsuoka, H. Takahashi, T. Sakamoto, S. Fukuda, M. Oku, T. Matsui, T. Morita, Y. Oyazato, K. Kimura, W. Moriya, S. Morimoto, S. Tsuiki, K. Shoji, M. Hata, J. Kubo, K. Yoshizawa, K. Nagayama, Y. Ozawa, M. Yoshida, M. Horiguchi, A. Machii, Y. Aiso, N. Kitahara, E. Kitazawa, K. Fukuda, N. Saiti, Y. Murakami, Y. Nao, I. Okazaki, K. Funatsu, K. Maruyama, B. Takagi, S. Yasuraoka, K. Ishii, S. Matsuzaki, H. Ishii, K. Kamegaya, K. Sambe, H. Ishikawa, Y. Tajima, A. Kuroda, Y. Ishihara, N. Sato, I. Ishikawa, T. Noro, Y. Kakumoto, H. S. Mekjian, N. R. Thomford, T. Yokomura, S. Adachi, A. Yamamoto, I. Saito, A. Kawamura, M. Miyata, S. Kasai, N. Kawanishi, A. Tamaki, M. Mito, Y. Kasai, A. Hasumi, T. Uchiyama, Y. Tachikawa, T. Takanashi, T. Kanke, K. Matsuda, G. Hamana, M. Sakuma, T. Sugita, K. Tomita, T. Tsuzuki, M. Uekusa, M. Matsuzaki, M. Tsuchiya, M. Uchimura, T. Murohisa, Y. Muto, J. Ishigaki, S. Waki, R. Tsuchiya, M. Sho, M. Furukawa, N. Suzuki, H. Nagashima, T. Matsushiro, T. Saitoh, N. Nakamura, T. Hatanaka, K. Tooi, Y. Tanaka, N. Kadokura, Y. Okada, I. Yanakgi, V. M. Sekiya, K. Adachi, M. Miyashita, Y. Moriyama, M. Onda, M. Yoshioka, T. Teraoka, Y. Shimizu, G. Fujishima, K. Ookawa, M. Miki, A. Shirota, K. Aihara, T. Shiga, H. Sano, S. Hayashi, M. Hori, H. Sato, Y. Chuman, S. Tsukase, N. Nakahara, S. Ehira, H. Nishimata, T. Irisa, K. Tokutome, Y. Nakashima, H. Koga, H. Yokoyama, T. Otsuji, Y. Chujo, S. Gotoda, S. Uchiyama, G. Kosaki, H. Ohkura, T. Mukojima, N. Hattori, O. Sasaki, K. Soejima, K. Inokuchi, J. Utsunomiya, T. Maki, T. Iwama, Y. Matsunaga, T. Shimomura, T. Nakajima, S. Ichikawa, T. Miyanaga, K. Sengoku, E. Hamaguchi, N. Aoki, T. Nomura, A. Matsuoka, A. Nagahama, T. Kazumi, H. Miyawaki, K. Miyasaki, K. Kato, Y. Miyazaki, N. Harada, K. Yamada, S. Tashiro, K. Sakai, N. Ho, H. Murayama, M. Yada, T. Sakabe, H. Shimizu, M. Kuroki, S. Nishida, S. Ishiyama, K. Yukawa, M. Hayashi, K. Soh, K. Doi, A. Nakagawa, E. Yukawa, Y. Uematsu, K. Nara, H. Hattori, M. Watanabe, K. Sato, S. Okuse, T. Murotani, S. Takasu, M. Konta, T. Uchiya, N. Fujimaki, K. Yoshikawa, M. Uchida, S. Kawana, K. Tamura, T. Hashimoto, T. Hara, J. Nosaka, O. Fukui, E. Inaba, S. Otsukasa, K. Sanada, H. Hiraide, G. Senyo, A. Ootani, T. Nakayama, S. Takei, H. Miki, S. Minota, K. Nakayama, K. Nakagawa, T. Shiraishi, H. Kawauchi, H. Nagaya, K. Mizushima, Y. Tachimi, M. Namiki, K. Masuda, N. Mitsutani, T. Mukuta, T. Koizumi, T. Takeuchi, T. Nemoto, H. Takabayashi, M. Takagi, Y. Hongo, H. Kojima, M. Nishimura, S. Hino, J. Hirayama, M. Nakamura, S. Koga, C. Hirayama, S. Kikuch, M. Ito, S. Hidano, T. Ooya, H. Banno, A. Tomura, T. Koyama, T. Takei, T. Tomimura, M. Yamauchi, Y. Nakaya, Y. Matsuda, K. Udo, N. Hukuda, M. Kametani, T. Miyagawa, T. Imaeda, K. Senda, H. Okubo, K. Kanoda, B. Miyashita, H. Ishizuka, T. Goto, K. Oto, H. Kaneda, M. Hase, J. Matsuda, T. Kawai, H. Ikehara, S. Baba, M. Ishii, T. Tozawa, E. Inoue, N. Mizuno, S. Saeki, T. Nakaji, T. Narabayashi, T. Okuno, H. Yamada, M. Tanno, K. Chiba, M. Iio, K. Shibata, F. Furuhashi, K. Mizuochi, S. Ohashi, M. Nakano, S. Otsuka, M. Irie, M. Akima, Y. Maruyama, F. Oyamada, E. Nagata, Y. Kubo, T. Arishima, Y. Otsuyama, A. Kaneto, Y. Shimogawa, K. Tanigawa, K. Nakajima, S. Onishi, A. Kasahara, T. Shimizu, Y. Ikehara, H. Tajima, A. Okamoto, T. Komibuchi, T. Negoro, A. Nihonsugi, Y. Ogawa, H. Otani, M. Ishida, H. Yashima, M. Ryo, T. Tanaka, K. Taketa, A. Watanabe, Y. Yumoto, A. Tanaka, A. Takesue, H. Aoe, M. Ueda, J. Shimamura, K. Kosaka, E. Kashiwara, K. Orita, E. Konaga, S. Kaneda, K. Ogawa, H. Tamura, S. Okanishi, T. Ueda, H. Horie, M. Kamachi, T. Asihara, R. Daido, T. Izumi, M. Kurihara, M. Sumida, M. Haraikawa, H. Hayakawa, H. Shirakabe, and A. Yasui

Subjects
medicine.medical_specialty, Common bile duct, business.industry, Digitoxin, General surgery, Gastroenterology, Hepatology, Colorectal surgery, Duodenal ulcer, medicine.anatomical_structure, Surgical oncology, Internal medicine, medicine, Obstructive jaundice, business, Abdominal surgery, medicine.drug
Published
1974
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13. [A Quality Assurance (QA) System with a Web Camera for High-dose-rate Brachytherapy].

Author

Hirose A, Ueda Y, Oohira S, Isono M, Tsujii K, Inui S, Masaoka A, Taniguchi M, Miyazaki M, and Teshima T

Subjects
Brachytherapy methods, Phantoms, Imaging, Radiotherapy Dosage, Radiotherapy, Image-Guided methods, Brachytherapy instrumentation, Quality Assurance, Health Care methods, Radiotherapy, Image-Guided instrumentation
Abstract

Purpose: The quality assurance (QA) system that simultaneously quantifies the position and duration of an (192)Ir source (dwell position and time) was developed and the performance of this system was evaluated in high-dose-rate brachytherapy., Methods: This QA system has two functions to verify and quantify dwell position and time by using a web camera. The web camera records 30 images per second in a range from 1,425 mm to 1,505 mm. A user verifies the source position from the web camera at real time. The source position and duration were quantified with the movie using in-house software which was applied with a template-matching technique., Results: This QA system allowed verification of the absolute position in real time and quantification of dwell position and time simultaneously. It was evident from the verification of the system that the mean of step size errors was 0.31±0.1 mm and that of dwell time errors 0.1±0.0 s. Absolute position errors can be determined with an accuracy of 1.0 mm at all dwell points in three step sizes and dwell time errors with an accuracy of 0.1% in more than 10.0 s of the planned time., Conclusion: This system is to provide quick verification and quantification of the dwell position and time with high accuracy at various dwell positions without depending on the step size.

Published
2016
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14. Asymmetric margin setting at the cranial and caudal sides in respiratory gated and non-gated stereotactic body radiotherapy for lung cancer.

Author

Ueda Y, Oohira S, Isono M, Miyazaki M, and Teshima T

Subjects
Aged, Female, Four-Dimensional Computed Tomography, Humans, Male, Reproducibility of Results, Respiration, Cauda Equina diagnostic imaging, Lung Neoplasms radiotherapy, Radiosurgery, Radiotherapy Planning, Computer-Assisted methods, Skull diagnostic imaging
Abstract

Objective: To evaluate total errors, including setup errors, and tumour motion changes with a electronic portal imaging device (EPID) cine at the cranial and caudal sides in respiratory gated and non-gated radiotherapy., Methods: Co-ordinates of the tumour centres (TCs) in the craniocaudal direction were obtained by using four-dimensional CT (4DCT) for each bin and EPID cine frame. During the 100% duty cycle (DC100), 50% duty cycle (DC50) and 30% duty cycle (DC30), both centred on the 50 phase, the co-ordinates of the TCs were compared at the most cranial and caudal positions on both 4DCT and EPID cine., Results: During DC100, total errors were -0.2 ± 2.1 and 1.1 ± 2.6 mm at the cranial and caudal sides, respectively. During DC50, the corresponding values were -0.2 ± 2.1 and 1.7 ± 3.2 mm, respectively; during DC30, they were -0.1 ± 2.1 and 1.8 ± 2.9 mm, respectively. The tumour motion changes at the caudal side were strongly correlated with tumour motion observed on 4DCT during DC100 (R(2) = 0.59)., Conclusion: Total errors and tumour motion changes on the caudal side were larger than on the cranial side because of the patients' breathing levels. Owing to variations of the TCs at beam-trigger events, the larger margin was required at the caudal side in gated radiotherapy., Advances in Knowledge: Variations of the TCs were evaluated at the cranial and caudal sides separately. Providing some margins to compensate for tumour motion changes was a significant requirement at the caudal side in gated and non-gated radiotherapy.

Published
2016
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15. Searching for the reasons for drop-out from peritoneal dialysis: a nationwide survey in Japan.

Author

Kawaguchi Y, Ishizaki T, Imada A, Oohira S, Kuriyama S, Nakamoto H, Nakamoto M, Hiramatu M, Maeda K, and Ota K

Subjects
Humans, Japan, Middle Aged, Surveys and Questionnaires, Patient Dropouts statistics & numerical data, Peritoneal Dialysis
Abstract

Purpose: We wanted to clarify, in a large population, the reasons that peritoneal dialysis (PD) was interrupted and to propose appropriate strategies that might prolong the use of PD as a renal replacement therapy., Patients and Methods: We enrolled 5 391 patients from 439 centers into the study. Each center used a worksheet to report details about patients who either transferred to hemodialysis (HD) or died on continuous ambulatory peritoneal dialysis (CAPD) over a 6-month period from 1 April 2000, to 30 September 2000., Results: We collected 252 drop-out cases from 141 centers. Of the 252 cases, 170 (67.5%) involved transfer to HD, and 82 (32.5%) involved death while on PD. Primary renal diseases were chronic nephritis (CN: 51.6%), diabetic nephropathy (DM: 26.6%), nephrosclerosis (4%), and unspecified or other condition (15.8%). Mean duration on PD in drop-out cases was 4.47 years. The age of patients at transfer to HD was younger (53.7 years) than the age of patients at death on PD (65.2 years). Patients with CN remained on PD significantly longer than did patients with DM (5 years vs 2.4 years). The three main reasons for PD discontinuation were overhydration because of ultrafiltration failure (UFF) or poor compliance with salt and fluid restrictions (34.1%); peritonitis (30.1%); and preference of the physician, patient, or family (6.5%). The proportional share represented by those three major reasons varied with the number of years since PD initiation (from 1 year to more than 8 years). Patients who had been on PD for a longer time were more likely to drop out because of UFF and less likely to drop out because of peritonitis. The three major causes of death on CAPD were cerebrovascular accident (22%), ischemic heart disease (14.6%), and sudden death (9.8%)., Conclusion: Approximately 10% of patients drop out from PD programs annually in Japan. To prolong PD treatment, new solutions that better preserve peritoneal function need to be developed, and patients and caregivers alike need to receive intensive education in preventing and treating peritonitis.

Published
2003

16. [A case of portal and superior mesenteric thrombosis associated with protein S deficiency treated with urokinase via the superior mesenteric vein].

Author

Yajima Y, Miyasato S, Miyazaki A, Eda Y, Sibuya D, and Oohira S

Subjects
Adult, Humans, Male, Venous Thrombosis etiology, Mesenteric Veins, Plasminogen Activators administration & dosage, Portal Vein, Protein S Deficiency complications, Urokinase-Type Plasminogen Activator administration & dosage, Venous Thrombosis drug therapy
Published
1999

18. [Efficacy and safety of sulbactam/cefoperazone for hepato-biliary infections].

Author

Shinagawa N, Takeda S, Oohira S, Yasuda Y, Fujisaki M, Saito H, Ueda M, Mitamura K, Nishio T, Itakura M, Koyama M, Hirano M, Ohyama R, Kako M, Amako Y, Okuda K, Iwasa T, Sugiyama A, Hirano M, Takashima S, Ohswawa N, Nakaya S, Yamada M, Zeze F, and Ishii J

Subjects
Adolescent, Adult, Aged, Aged, 80 and over, Cefoperazone adverse effects, Drug Combinations, Enterococcus, Female, Humans, Klebsiella Infections drug therapy, Male, Middle Aged, Neoplasms complications, Pseudomonas Infections drug therapy, Sulbactam adverse effects, Treatment Outcome, Cefoperazone administration & dosage, Cholangitis drug therapy, Cholecystitis drug therapy, Liver Abscess drug therapy, Sulbactam administration & dosage
Abstract

We studied efficacy and safety of sulbactam/cefoperazone (SBT/CPT) in the treatment of biliary tract infections in hospitalized patients at 26 hospitals from February 1993 to March 1995. Secondary to dropout, 273 out of 338 patients entered in the study were evaluated, 127 patients with cholecystitis, 132 patients with cholangitis, and 14 patients with liver abscesses. Of these, 93 patients (34.1% had malignancy as an underlying disease. SBT/CPZ had an efficacy of 79.9% (218 patients; excellent: 52, good: 166), with the efficacy in patients with cholecystitis, cholangitis and liver abscess at 89.0% (113 patients), 77.3% (102 patients and 21.4% (3 patients), respectively. A significant difference (p < 0.05) was observed in the efficacy rates of patients with (59 patients [63.4%]) and without malignancy (159 patients [88.3%]). A total of 84 strains were isolated from bile specimens of 53 patients, and the major isolates were Escherichia coli, Pseudomonas aeruginosa and Enterococcus spp. Two or more bacterial strains were isolated simultaneously in 20 patients. Mild or moderate side effect (allergic reaction including rash etc.) were noted in 4 patients (1.18%), and laboratory abnormalities (increased GOT, etc.) were in 16 patients (4.71%) out of the total 338 patients. This study clearly demonstrated that SBT/CPZ retains its excellent clinical efficacy and safety profile, throughout its use over the past decade.

Published
1997

20. [Report of twenty-one cases of blowout fracture].

Author

Hori T, Ishida M, Oohira S, Tamaki H, Matsunaga T, and Oomoto T

Subjects
Adolescent, Adult, Child, Child, Preschool, Female, Humans, Japan, Male, Maxillary Fractures diagnosis, Maxillary Sinus, Middle Aged, Orbital Fractures diagnosis, Sex Factors, Orbital Fractures epidemiology, Skull Fractures epidemiology
Published
1982

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