Yoshinori Funama

Summary

Affiliation: Kumamoto University
Country: Japan

Publications

  1. doi request reprint Automatic exposure control at single- and dual-heartbeat CTCA on a 320-MDCT volume scanner: Effect of heart rate, exposure phase window setting, and reconstruction algorithm
    Yoshinori Funama
    Department of Medical Physics, Faculty of Life Sciences, Kumamoto University, 4 24 1 Kuhonji, Kumamoto, Japan Electronic address
    Phys Med 30:385-90. 2014
  2. doi request reprint Automatic exposure control at MDCT based on the contrast-to-noise ratio: theoretical background and phantom study
    Yoshinori Funama
    Department of Medical Physics, Faculty of Life Sciences, Kumamoto University, Kumamoto, Japan
    Phys Med 29:39-47. 2013
  3. doi request reprint Dose profiles for lung and breast regions at prospective and retrospective CT coronary angiography using optically stimulated luminescence dosimeters on a 64-detector CT scanner
    Yoshinori Funama
    Department of Medical Physics, Faculty of Life Sciences, Kumamoto University, 4 24 1 Kuhonji, Kumamoto 862 0976, Japan
    Phys Med 28:76-82. 2012
  4. doi request reprint Coronary artery stent evaluation by combining iterative reconstruction and high-resolution kernel at coronary CT angiography
    Yoshinori Funama
    Department of Medical Physics, Faculty of Life Sciences, Kumamoto University, Kuhonji, Japan
    Acad Radiol 19:1324-31. 2012
  5. pmc Combination of a low-tube-voltage technique with hybrid iterative reconstruction (iDose) algorithm at coronary computed tomographic angiography
    Yoshinori Funama
    Department of Medical Physics, Faculty of Life Sciences, Kumamoto University, Kumamoto, Japan
    J Comput Assist Tomogr 35:480-5. 2011
  6. doi request reprint Detection of nodules showing ground-glass opacity in the lungs at low-dose multidetector computed tomography: phantom and clinical study
    Yoshinori Funama
    Department of Radiological Sciences, School of Health Sciences, Kumamoto University, Kumamoto, Japan
    J Comput Assist Tomogr 33:49-53. 2009
  7. doi request reprint Image noise and radiation dose using an automatic tube current modulation technique at 64-detector computed tomography: effect of off-center patient position, bowtie filter type, and scan projection radiograph
    Yoshinori Funama
    Department of Radiological Sciences, School of Health Sciences, Kumamoto University, Kumamoto, Japan
    J Comput Assist Tomogr 33:973-7. 2009
  8. doi request reprint Radiation exposure of operator performing interventional procedures using a flat panel angiography system: evaluation with photoluminescence glass dosimeters
    Yoshinori Funama
    Department of Medical Physics, Faculty of Life Sciences, Kumamoto University, 4 24 1 Kuhonji, Kumamoto, 862 0976, Japan
    Jpn J Radiol 28:423-9. 2010
  9. ncbi request reprint Radiation dose reduction in hepatic multidetector computed tomography with a novel adaptive noise reduction filter
    Yoshinori Funama
    Department of Radiological Sciences, School of Health Sciences, Kumamoto University, 4 24 1 Kuhonji, Kumamoto 862 0976, Japan
    Radiat Med 26:171-7. 2008
  10. ncbi request reprint Improvement of low-contrast detectability in low-dose hepatic multidetector computed tomography using a novel adaptive filter: evaluation with a computer-simulated liver including tumors
    Yoshinori Funama
    Department of Medical Information Systems, School of Health Sciences, Kumamoto University, Japan
    Invest Radiol 41:1-7. 2006

Collaborators

Detail Information

Publications42

  1. doi request reprint Automatic exposure control at single- and dual-heartbeat CTCA on a 320-MDCT volume scanner: Effect of heart rate, exposure phase window setting, and reconstruction algorithm
    Yoshinori Funama
    Department of Medical Physics, Faculty of Life Sciences, Kumamoto University, 4 24 1 Kuhonji, Kumamoto, Japan Electronic address
    Phys Med 30:385-90. 2014
    ..To investigate whether electrocardiogram (ECG)-gated single- and dual-heartbeat computed tomography coronary angiography (CTCA) with automatic exposure control (AEC) yields images with uniform image noise at reduced radiation doses...
  2. doi request reprint Automatic exposure control at MDCT based on the contrast-to-noise ratio: theoretical background and phantom study
    Yoshinori Funama
    Department of Medical Physics, Faculty of Life Sciences, Kumamoto University, Kumamoto, Japan
    Phys Med 29:39-47. 2013
    ..To develop a new automatic exposure control (AEC) technique based on the contrast-to-noise ratio (CNR) and provide constant lesion detectability...
  3. doi request reprint Dose profiles for lung and breast regions at prospective and retrospective CT coronary angiography using optically stimulated luminescence dosimeters on a 64-detector CT scanner
    Yoshinori Funama
    Department of Medical Physics, Faculty of Life Sciences, Kumamoto University, 4 24 1 Kuhonji, Kumamoto 862 0976, Japan
    Phys Med 28:76-82. 2012
    ....
  4. doi request reprint Coronary artery stent evaluation by combining iterative reconstruction and high-resolution kernel at coronary CT angiography
    Yoshinori Funama
    Department of Medical Physics, Faculty of Life Sciences, Kumamoto University, Kuhonji, Japan
    Acad Radiol 19:1324-31. 2012
    ..To evaluate stent lumen visualization by combining high-resolution cardiac kernel and the iterative reconstruction (iDose) on an anthropomorphic moving heart phantom and in patients at coronary computed tomography (CT) angiography...
  5. pmc Combination of a low-tube-voltage technique with hybrid iterative reconstruction (iDose) algorithm at coronary computed tomographic angiography
    Yoshinori Funama
    Department of Medical Physics, Faculty of Life Sciences, Kumamoto University, Kumamoto, Japan
    J Comput Assist Tomogr 35:480-5. 2011
    ..Image quality was the same or better despite a reduction in the radiation dose by 76% compared with standard tube voltage with FBP...
  6. doi request reprint Detection of nodules showing ground-glass opacity in the lungs at low-dose multidetector computed tomography: phantom and clinical study
    Yoshinori Funama
    Department of Radiological Sciences, School of Health Sciences, Kumamoto University, Kumamoto, Japan
    J Comput Assist Tomogr 33:49-53. 2009
    ..To investigate the effect of the radiation dose (tube current second product) and the attenuation value of nodules with ground-glass opacity (GGO) on their detectability at multidetector computed tomography (MDCT)...
  7. doi request reprint Image noise and radiation dose using an automatic tube current modulation technique at 64-detector computed tomography: effect of off-center patient position, bowtie filter type, and scan projection radiograph
    Yoshinori Funama
    Department of Radiological Sciences, School of Health Sciences, Kumamoto University, Kumamoto, Japan
    J Comput Assist Tomogr 33:973-7. 2009
    ..On lateral scan projection radiographs, it remained constant with each bowtie filter type regardless of the off-center phantom position...
  8. doi request reprint Radiation exposure of operator performing interventional procedures using a flat panel angiography system: evaluation with photoluminescence glass dosimeters
    Yoshinori Funama
    Department of Medical Physics, Faculty of Life Sciences, Kumamoto University, 4 24 1 Kuhonji, Kumamoto, 862 0976, Japan
    Jpn J Radiol 28:423-9. 2010
    ..Using glass rod dosimeters we investigated the radiation dose to the operator performing interventional procedures in 43 patients with the aid of a monoplane flat detector-based angiography system...
  9. ncbi request reprint Radiation dose reduction in hepatic multidetector computed tomography with a novel adaptive noise reduction filter
    Yoshinori Funama
    Department of Radiological Sciences, School of Health Sciences, Kumamoto University, 4 24 1 Kuhonji, Kumamoto 862 0976, Japan
    Radiat Med 26:171-7. 2008
    ..The aim of this study was to optimize a novel adaptive noise reduction filter based on patient body weight and to investigate its utility for improving the image quality of low-dose hepatic computed tomography (CT) scans...
  10. ncbi request reprint Improvement of low-contrast detectability in low-dose hepatic multidetector computed tomography using a novel adaptive filter: evaluation with a computer-simulated liver including tumors
    Yoshinori Funama
    Department of Medical Information Systems, School of Health Sciences, Kumamoto University, Japan
    Invest Radiol 41:1-7. 2006
    ....
  11. ncbi request reprint Hypervascular hepatocellular carcinomas: bolus tracking with a 40-detector CT scanner to time arterial phase imaging
    Shamima Sultana
    Department of Diagnostic Radiology, Graduate School of Medical Sciences, Kumamoto University, 1 1 2 Honjyo, Kumamoto 860 8556, Japan
    Radiology 243:140-7. 2007
    ..To evaluate prospectively bolus tracking to time hepatic arterial phase (HAP) imaging of hypervascular hepatocellular carcinomas (HCCs) with a 40-detector computed tomographic (CT) scanner...
  12. doi request reprint Identification and characterization of focal ground-glass opacity in the lungs by high-resolution CT using thin-section multidetector helical CT: experimental study using a chest CT phantom
    Duo Liu
    Department of Diagnostic Radiology, Graduate School of Medical Sciences, Kumamoto University, 1 1 1 Honjo, Kumamoto 860 8556, Japan
    Radiat Med 26:21-7. 2008
    ..The aim of this study was to investigate how much the radiation dose can be reduced for the identification and characterization of focal ground-glass opacities (GGOs) by high resolution computed tomography (HRCT)...
  13. doi request reprint Cone-beam technique for 64-MDCT of lung: image quality comparison with stepwise (step-and-shoot) technique
    Yoshinori Funama
    Department of Radiological Sciences, School of Health Sciences, Kumamoto University, 4 24 1 Kuhonji, Kumamoto 862 0976, Japan
    AJR Am J Roentgenol 192:273-8. 2009
    ....
  14. doi request reprint Effect of contrast injection protocols with dose adjusted to the estimated lean patient body weight on aortic enhancement at CT angiography
    Yumi Yanaga
    Department of Diagnostic Radiology, Graduate School of Medical Sciences, Kumamoto University, 1 1 1 Honjo, Kumamoto 860 8556, Japan
    AJR Am J Roentgenol 192:1071-8. 2009
    ..The objective of our study was to investigate the effect on aortic enhancement of iodine doses adjusted for the patient estimated lean body weight (LBW) at CT angiography (CTA)...
  15. ncbi request reprint Detection of early enhancement of hypervascular hepatocellular carcinoma using single breath-hold 3D pixel shift dynamic subtraction MDCT
    Takeshi Nakaura
    Department of Diagnostic Radiology, Graduate School of Medical Sciences, Kumamoto University, 1 1 1 Honjyo, Kumamoto 860 8556, Japan
    AJR Am J Roentgenol 190:W13-8. 2008
    ..The objective of our study was to evaluate the effect of single breath-hold dynamic subtraction MDCT of the liver on the performance of radiologists in detecting focal enhancement during the hepatic arterial phase...
  16. doi request reprint Optimal contrast dose for depiction of hypervascular hepatocellular carcinoma at dynamic CT using 64-MDCT
    Yumi Yanaga
    Department of Diagnostic Radiology, Graduate School of Medical Sciences, Kumamoto University, 1 1 1 Honjo, Kumamoto, 860 8556 Japan
    AJR Am J Roentgenol 190:1003-9. 2008
    ..The objective of our study was to investigate prospectively the optimal contrast dose for the depiction of hypervascular hepatocellular carcinoma (HCC) during the hepatic arterial phase (HAP) at dynamic CT using a 64-MDCT scanner...
  17. doi request reprint A hybrid iterative reconstruction algorithm that improves the image quality of low-tube-voltage coronary CT angiography
    Seitaro Oda
    Department of Diagnostic Radiology, Faculty of Life Sciences, Kumamoto University, Japan
    AJR Am J Roentgenol 198:1126-31. 2012
    ..We investigated whether a hybrid iterative reconstruction (HIR) algorithm improves image quality at low-tube-voltage coronary CT angiography (CTA) compared with filtered back projection (FBP)...
  18. doi request reprint Uniform vascular enhancement of lower-extremity artery on CT angiography using test-injection monitoring at the central level of the scan range: a simulation flow phantom study with clinical correlation
    Kie Shimizu
    Central Radiology, Kumamoto University, Kumamoto shi, Kumamoto, 860 8556, Japan
    Acad Radiol 17:1153-7. 2010
    ..To evaluate the efficacy of variable contrast injection durations and scanning delay determined by test injection analysis of computed tomography angiography (CTA) of peripheral arteries...
  19. doi request reprint Effects of dual-energy subtraction chest radiography on detection of small pulmonary nodules with varying attenuation: receiver operating characteristic analysis using a phantom study
    Seitaro Oda
    Department of Diagnostic Radiology, Graduate School of Medical Sciences, Kumamoto University, Honjo, Kumamoto, Japan
    Jpn J Radiol 28:214-9. 2010
    ..The aim of this study was to investigate the detectability of simulated pulmonary nodules with different X-ray attenuation by flat-panel detector (FPD) chest radiography using a dual-exposure dual-energy subtraction (DES) technique...
  20. doi request reprint A low tube voltage technique reduces the radiation dose at retrospective ECG-gated cardiac computed tomography for anatomical and functional analyses
    Seitaro Oda
    Department of Diagnostic Radiology, Faculty of Life Sciences, Kumamoto University, 1 1 1 Honjyo, Kumamoto, 860 8556, Japan
    Acad Radiol 18:991-9. 2011
    ..To investigate the effect of low-tube-voltage technique on a cardiac computed tomography (CT) for coronary arterial and cardiac functional analyses and radiation dose in slim patients...
  21. ncbi request reprint Optimal dose and injection duration (injection rate) of contrast material for depiction of hypervascular hepatocellular carcinomas by multidetector CT
    Yumi Yanaga
    Department of Diagnostic Radiology, Kumamoto University Graduate School of Medical Sciences, 1 1 1 Honjyo, Kumamoto, 860 8556, Japan
    Radiat Med 25:278-88. 2007
    ....
  22. doi request reprint Dynamic computed tomography of locally advanced pancreatic cancer: effect of low tube voltage and a hybrid iterative reconstruction algorithm on image quality
    Sadahiro Yamamura
    From the Departments of Diagnostic Radiology, Medical Physics, and Gastroenterological Surgery, Faculty of Life Sciences, Kumamoto University, Kumamoto, Japan
    J Comput Assist Tomogr 37:790-6. 2013
    ..The objective of this study was to evaluate the effect of a low-tube-voltage technique and hybrid iterative reconstruction (HIR) on image quality at dynamic computed tomography (CT) of the pancreas...
  23. ncbi request reprint Abdominal CT with low tube voltage: preliminary observations about radiation dose, contrast enhancement, image quality, and noise
    Yoshiharu Nakayama
    Department of Diagnostic Radiology, Graduate School of Medical Sciences, Kumamoto University, 1 1 1 Honjo, Kumamoto 860 8556, Japan
    Radiology 237:945-51. 2005
    ..To prospectively investigate the effect of low tube voltage on radiation dose, contrast enhancement, image quality, and image noise at abdominal dynamic computed tomography (CT)...
  24. doi request reprint Automatic tube current modulation technique for multidetector CT: is it effective with a 64-detector CT?
    Yoshinori Funama
    Department of Radiological Sciences, School of Health Sciences, Kumamoto University, Kuhonji, Kumamoto, Japan
    Radiol Phys Technol 1:33-7. 2008
    ..6 mAs at the center of the spleen. The mean dose reduction rate per constant tube current at 175 mAs ranged from 3.1 to 39.5%. By use of the ATCM technique, it is possible to maintain a constant image noise level with a 64-detector CT...
  25. doi request reprint Low contrast agent and radiation dose protocol for hepatic dynamic CT of thin adults at 256-detector row CT: effect of low tube voltage and hybrid iterative reconstruction algorithm on image quality
    Takeshi Nakaura
    Department of Diagnostic Radiology, Amakusa Medical Center, Amakusa, Kumamoto, Japan
    Radiology 264:445-54. 2012
    ....
  26. doi request reprint Comparison of standard- and low-tube voltage MDCT angiography in patients with peripheral arterial disease
    Daisuke Utsunomiya
    Department of Diagnostic Radiology, Graduate School of Medical Sciences, Kumamoto University, 1 1 1, Honjo, Kumamoto shi, Kumamoto, 860 8556, Japan
    Eur Radiol 20:2758-65. 2010
    ..We investigated the effect of low-tube-voltage CT angiography with a reduced volume of contrast agent on qualitative and quantitative parameters and the radiation dose in patients with peripheral arterial disease...
  27. ncbi request reprint Prediction of aortic peak enhancement in monophasic contrast injection protocols at multidetector CT: phantom and patient studies
    Kazuo Awai
    Department of Diagnostic Radiology, Graduate School of Medical Sciences, Kumamoto University, 1 1 1 Honjo, Kumamoto 860 8556, Japan
    Radiat Med 25:14-21. 2007
    ..The aim of this study was to investigate whether it is possible to predict aortic peak enhancement (APE) from the contrast dose and injection rate...
  28. doi request reprint Low-dose MDCT urography: feasibility study of low-tube-voltage technique and adaptive noise reduction filter
    Yumi Yanaga
    Department of Diagnostic Radiology, Graduate School of Medical Sciences, Kumamoto University, 1 1 1 Honjo, Kumamoto, 860 8556, Japan
    AJR Am J Roentgenol 193:W220-9. 2009
    ..The purpose of this study was to investigate the feasibility of performance of MDCT urography with low tube voltage and an adaptive noise reduction filter...
  29. doi request reprint Hepatocellular carcinoma in patients weighing 70 kg or less: initial trial of compact-bolus dynamic CT with low-dose contrast material at 80 kVp
    Yumi Yanaga
    Department of Diagnostic Radiology, Faculty of Life Sciences, Kumamoto University, Kumamoto, Japan
    AJR Am J Roentgenol 196:1324-31. 2011
    ....
  30. ncbi request reprint Pulmonary nodules: estimation of malignancy at thin-section helical CT--effect of computer-aided diagnosis on performance of radiologists
    Kazuo Awai
    Department of Diagnostic Radiology, Graduate School of Medical Sciences, Kumamoto University, 1 1 1 Honjyo, Kumamoto 860 8556, Japan
    Radiology 239:276-84. 2006
    ..To evaluate the effect of a computer-aided diagnosis (CAD) system on the diagnostic performance of radiologists for the estimation of the malignancy of pulmonary nodules on thin-section helical computed tomographic (CT) scans...
  31. ncbi request reprint Evaluation of deep vein thrombosis with reduced radiation and contrast material dose at computed tomography venography: clinical application of a combined iterative reconstruction and low-tube-voltage technique
    Seitaro Oda
    Department of Diagnostic Radiology, Faculty of Life Sciences, Kumamoto University, Kumamoto, Japan
    Circ J 76:2614-22. 2012
    ..A low-tube-voltage technique with iterative reconstruction may overcome this problem. The aim of this study was to investigate the effects of hybrid iterative reconstruction (HIR) on image quality at low-tube-voltage CTV...
  32. ncbi request reprint Reduction of radiation dose at HRCT of the temporal bone in children
    Yoshinori Funama
    Department of Medical Information Systems, School of Health Sciences, Kumamoto University, 4 24 1 Kuhonji, Kumamoto 862 0976, Japan
    Radiat Med 23:578-83. 2005
    ..The purpose of this study was to reduce the radiation exposure of the eye lens in high resolution computed tomography (HRCT) of the temporal bone using an experimental phantom...
  33. doi request reprint Baseline incidence and severity of renal insufficiency evaluated by estimated glomerular filtration rates in patients scheduled for contrast-enhanced CT
    Daisuke Utsunomiya
    Department of Diagnostic Radiology, Faculty of Life Sciences, Kumamoto University, Japan
    Acta Radiol 52:581-6. 2011
    ....
  34. ncbi request reprint Lower tube voltage reduces contrast material and radiation doses on 16-MDCT aortography
    Yoshiharu Nakayama
    Department of Diagnostic Radiology, Graduate School of Medical Sciences, Kumamoto University, 1 1 1 Honjo, Kumamoto 860 8556, Japan
    AJR Am J Roentgenol 187:W490-7. 2006
    ..The purpose of our study was to compare aortic CT angiography performed at a low tube voltage and reduced dose of contrast material with standard-voltage, standard-contrast-dose CT angiography...
  35. doi request reprint Improved coronary in-stent visualization using a combined high-resolution kernel and a hybrid iterative reconstruction technique at 256-slice cardiac CT-Pilot study
    Seitaro Oda
    Department of Diagnostic Radiology, Faculty of Life Sciences, Kumamoto University, 1 1 1 Honjyo, Kumamoto 860 8556, Japan
    Eur J Radiol 82:288-95. 2013
    ..To investigate the diagnostic performance of 256-slice cardiac CT for the evaluation of the in-stent lumen by using a hybrid iterative reconstruction (HIR) algorithm combined with a high-resolution kernel...
  36. doi request reprint Optimal setting of automatic exposure control based on image noise and contrast on iodine-enhanced CT
    Hiroo Murazaki
    Department of Health Sciences, Graduate School of Health Sciences, Kumamoto University, Japan
    Acad Radiol 19:478-84. 2012
    ..The aim of this study was to investigate variations in image noise and contrast using automatic exposure control (AEC) and different tube voltages on nonenhanced and iodine-enhanced hepatic computed tomography...
  37. doi request reprint Performance of radiologists in detection of small pulmonary nodules on chest radiographs: effect of rib suppression with a massive-training artificial neural network
    Seitaro Oda
    Department of Diagnostic Radiology, Graduate School of Medical Sciences, Kumamoto University, Kumamoto 860 8556, Japan
    AJR Am J Roentgenol 193:W397-402. 2009
    ..We investigated the effect of rib suppression with a massive-training artificial neural network on the performance of radiologists in the detection of pulmonary nodules on chest radiographs...
  38. ncbi request reprint Radiation dose reduction without degradation of low-contrast detectability at abdominal multisection CT with a low-tube voltage technique: phantom study
    Yoshinori Funama
    Department of Radiological Sciences, School of Health Sciences, Kumamoto University, 4 24 1 Kuhonji, Kumamoto 862 0976, Japan
    Radiology 237:905-10. 2005
    ..To reduce radiation dose from abdominal computed tomography (CT) without degradation of low-contrast detectability by using a technique with low tube voltage (90 kV)...
  39. doi request reprint A knowledge-based iterative model reconstruction algorithm: can super-low-dose cardiac CT be applicable in clinical settings?
    Seitaro Oda
    Department of Diagnostic Radiology, Faculty of Life Sciences, Kumamoto University, 1 1 1 Honjyo, Chuo Ku, Kumamoto, 860 8556, Japan Electronic address
    Acad Radiol 21:104-10. 2014
    ..To investigate whether "full" iterative reconstruction, a knowledge-based iterative model reconstruction (IMR), enables radiation dose reduction by 80% at cardiac computed tomography (CT)...
  40. ncbi request reprint A computer-simulated liver phantom (virtual liver phantom) for multidetector computed tomography evaluation
    Yoshinori Funama
    Department of Radiological Sciences, School of Health Sciences, Kumamoto University, Japan
    Eur Radiol 16:837-45. 2006
    ..The purpose of study was to develop a computer-simulated liver phantom for hepatic CT studies. A computer-simulated liver phantom was mathematically constructed on a computer workstation...
  41. doi request reprint Three-dimensional computed tomographic angiography of the liver for planning hepatic surgery: effect of low tube voltage and the iterative reconstruction algorithm on image quality
    Keiichi Honda
    From the Department of Radiology, Kumamoto Chuo Hospital, Kumamoto, Japan Department of Diagnostic Radiology, Faculty of Life Sciences, Kumamoto University, Kumamoto, Japan Department of Surgery, Kumamoto Chuo Hospital, Kumamoto, Japan and Department of Medical Physics, Faculty of Life Sciences, Kumamoto University, Kumamoto, Japan
    J Comput Assist Tomogr 38:131-6. 2014
    ..The aim of this study was to evaluate the effect of a low tube voltage technique and hybrid iterative reconstruction (HIR) on image quality at 3-dimensional computed tomographic angiography (3D-CTA) of the liver...
  42. ncbi request reprint [Radiation reduction and image quality improvement with iterative reconstruction at multidetector-row computed tomography]
    Satoshi Kihara
    Course of Radiological Sciences, School of Health Sciences, Kumamoto University
    Nihon Hoshasen Gijutsu Gakkai Zasshi 67:1426-32. 2011
    ..From our findings, iDose facilitates the reduction in radiation dose while maintaining image quality...