Keizo Murakawa

National Cerebral and Cardiovascular Center

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Yoshihiro Nishimura

Kobe University

Hisashi Oka

JVC Kenwood (Japan)

Tetsuro Katafuchi

Gifu University of Medical Science

Masayoshi Sago

National Cerebral and Cardiovascular Center

Tetsuya Fukuda

National Cerebral and Cardiovascular Center

Toshihiro Nishino

Shinshu University

Yasutoshi Ohta

National Cerebral and Cardiovascular Center

Wataru Ueki

National Cerebral and Cardiovascular Center

Masanobu Yamada

Gunma University

Emi Tateishi

National Cerebral and Cardiovascular Center

Cooperative Institutions

National Cerebral and Cardiovascular Center

National Institutes for Quantum and Radiological Science and Technology

Kanazawa University

Siemens Healthcare (United States)

Osaka University

Tohoku University Hospital

National Hospital Organization

Tohoku University

Tottori University Hospital

Kobe University

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Accuracy of cardiac function using QGS in myocardial gated SPECT.

Japanese Journal of Radiological Technology (1997)

Keizo Murakawa Tetsuro Katafuchi Hisashi Oka Masayoshi Sago Yoshihiro Nishimura

検討 Aceuracy of cardiac

Gated SPECT

10.6009/jjrt.kj00001356053

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Assessment of myocardial microstructural change using novel motion compensated technique in cardiac diffusion tensor imaging

Proceedings on CD-ROM - International Society for Magnetic Resonance in Medicine. Scientific Meeting and Exhibition/Proceedings of the International Society for Magnetic Resonance in Medicine, Scientific Meeting and Exhibition (2023)

Wataru Ueki Yoshiaki Morita Yu Ueda Masaru Shiotani Tatsuhiro Yamamoto

The accelerated motion compensation (aMC) using higher order motion compensated gradients with asymmetric bipolar diffusion waveform can improve the image quality of cardiac DTI compared with conventional method and provide the relatively constant DTI marker. In LVH patients, aMC-DTI derived possible preliminary insights into detection of abnormal changes in myocardial microstructures in-vivo, even in segments without LGE.

10.58530/2022/4140

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Assessment of myocardial involvement in patients with Fabry disease using metabolic imaging by 1H-MR Spectroscopy (1H-MRS)

Masaru Shiotani Yoshiaki Morita Yoshito Ichiba Yasuhiro Nagai Wataru Ueki

The peak ratio of 3.5ppm to water in 1H-MRS of myocardium showed the higher values in Fabry disease and the association with native T1 values and regional function. 1H-MRS has a potential as disease-specific imaging biomarker for direct quantification of myocardial sphingolipid accumulation of Fabry disease.

Sphingolipid

Globotriaosylceramide

Fabry's disease

10.58530/2022/4156

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Diagnosis and therapeutic indication of coronary artery disease: from the perspective of quantitative assessment by SPECT imaging

心臓核医学 (2017)

Keisuke Kiso Emi Tateishi Keizo Murakawa Akira Imoto Yusuke Terakawa

Spect imaging

Source

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Development of Body Phantom for Evaluation of Appropriate Administered Radioactivities and Image Quality on <sup>99m</sup>Tc-DMSA Scintigraphy in Pediatric Nuclear Medicine

Japanese Journal of Radiological Technology (2017)

Akio Nagaki Katsuya Sugimoto Yoshihiro Nishimura Keizo Murakawa Takeharu Andoh

Purpose: We conducted a field survey about pediatric nuclear medicine. As a result, it was suggested that 99mTc-DMSA scintigraphy was performed at many institutions, whereas various examinations such as image acquisition and processing are not carried out using the renal phantom. Therefore, we developed the body phantom for the evaluation of appropriate administered radioactivities and image quality with renal scintigraphy in pediatric nuclear medicine. Methods: We created three differently sized body phantoms (1-, 5-, and 20-year-old models). These pediatric body phantoms were filled with a 99mTc solution based on the consensus guideline of pediatric radiopharmaceutical administered radioactivity in Japan. The planar image was evaluated using acquisition count, uniformity and defect contrast. SPECT images were evaluated with a recovery coefficient (RC). Results: The acquisition counts for pediatric body phantoms were relatively corresponded to the clinical study. The appropriate acquisition counts and the pixel size for the planar image were approximately 140 counts per pixel and 1.23–1.35 mm at 5 min acquisition times in 1- and 5-year-old pediatric body phantom studies, respectively. Although the uniformity and the cold contrast did not depend on pixel size and body size, the cold contrast was affected by body size. The RC for SPECT images depended on the performance of SPECT systems, the resolution recovery algorithm and body phantom size. Conclusion: The developed pediatric body phantom could allow us to establish optimal image acquisition and more evidence on renal scintigraphy in pediatric nuclear medicine.

Gamma camera

10.6009/jjrt.2017_jsrt_73.12.1197

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The Feasibility of Quantitative Assessment of Myocardial Perfusion Using Single Photon Emission Computed Tomography Imaging

Annals of Nuclear Cardiology (2017)

Keisuke Kiso Emi Tateishi Akira Imoto Yusuke Terakawa Keizo Murakawa

Assessment of physiological ischemia is recently essential for the indication of coronary revascularization; such as percutaneous coronary intervention (PCI) and coronary artery bypass graft (CABG) in patients with coronary artery disease. Moreover, quantitative assessment of myocardial flow reserve (MFR) is also getting important role for the evaluation of prognosis of heart diseases including non-ischemic cardiomyopathy.In the field of nuclear cardiology, positron emission tomography (PET) has been the only modality for the quantitative assessment of myocardial blood flow (MBF) and MFR. However, since availability of PET is much less than that of single photon emission computed tomography (SPECT) imaging, quantitative MBF/MFR assessment has been limited.Recently, high sensitivity gamma camera which equipped semiconductor detectors has been developed. It is reported that its image quality and spatial resolution are much superior to conventional Anger-type gamma camera. Moreover, since high sensitivity gamma camera consists of plural detectors, it can evaluate whole heart perfusion simultaneously. These advances make quantitative MBF/MFR analysis feasible like PET imaging. Although quantitative assessment with high sensitivity gamma camera is getting useful in clinical practice, several points; such as acquisition protocol and analysis methods, are immature compared to PET. Therefore, we have to investigate the solutions for these issues in near future for diagnostic certainty.

Gamma camera

Cardiac PET

10.17996/anc.17-00048

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A Study of Fundamental Properties of Dual-Headed Gamma Camera :(ADAC VERTEX EPIC)

Japanese Journal of Radiological Technology (1997)

Keizo Murakawa Tetsuro Katafuchi Hisashi Oka Masanobu Yamada Toshihiro Nishino

Improvement in the performance of SPECT cameras has been remarkable. A highly sophisticated SPECT camera, the VERTEX EPIC from ADAC Laboratories, USA, was installed at our institution. The VERTEX has variable angle dual detectors and provides a fully digitized signal, the first such camera in japan. To examine the characteristics of this camera, we investigated its basic performance. The results of our study indicated the performance of this camera was satisfactory for clinical use. Intrinsic uniformity was 1.85%, intrinsic resolution 3.13mm, FWHM of SPECT(VXHR)8.2mm, and visual resolution 6.0mm. The VERTEX EPIC can play a role in various examinations in the field of clinical nuclear.

Gamma camera

Field of view

10.6009/jjrt.kj00001355780

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Evaluation of sampling angle for myocardial SPECT using two head detector gamma camera.

Japanese Journal of Radiological Technology (1996)

Keizo Murakawa Tetsuro Katafuchi Hisashi Oka Masanobu Yamada Toshihiro Nishino

Evaluation of sampling angle for

Gamma camera

10.6009/jjrt.kj00001354860

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Usefulness of Attenuation Correction with Transmission Source in Myocardial SPECT

Japanese Journal of Radiological Technology (2006)

Keizo Murakawa Tetsuro Katafuchi Yoshihiro Nishimura Naoyuki Enomoto Masayoshi Sago

Attenuation correction in SPECT has been used for uniformly absorptive objects like the head. On the other hand, it has seldom been applied to nonuniform absorptive objects like the heart and surrounding lungs because of the difficulty and inaccuracy of data processing. However, since attenuation correction using a transmission source recently became practical, we were able to apply this method to a nonuniform absorptive object. Therefore, we evaluated the usefulness of this attenuation correction system with a transmission source in myocardial SPECT. The dose linearity, defect/normal ratio using a myocardial phantom, and myocardial count distribution in clinical cases was examined with and without the attenuation correction system. We found that all data processed with attenuation correction were better than those without attenuation correction. For example, in myocardial count distribution, while there was a difference between men and women without attenuation correction, which was considered to be caused by differences in body shape, after processing with attenuation correction, myocardial count distribution was almost the same in all cases. In conclusion, these results suggested that attenuation correction with a transmission source was useful in myocardial SPECT.

Correction for attenuation

10.6009/jjrt.62.70

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Citations (3)

1. Comparison of the Cardiac Function Analysis Software in Gated SPECT (Symposium I : Usefulness of Cardiac Function Assessment by Gated SPECT) (The 59th Annual Scientific Congress)

Japanese Journal of Radiological Technology (2004)

Keizo Murakawa

Gated SPECT

Spect imaging

10.6009/jjrt.kj00000922332

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