LIVIVO - Search results -

Search results

Result 1 - 10 of total 31

Search options

Article ; Online: PATIENT-SPECIFIC ORGAN DOSE EVALUATION BASED ON MONTE CARLO SIMULATION AND DOSE METRICS IN PAEDIATRIC CHEST-ABDOMEN-PELVIS CT EXAMINATIONS.

Fujii, Keisuke / Nomura, Keiichi / Muramatsu, Yoshihisa / Ota, Hiroyuki

2021 Volume 197, Issue 1, Page(s) 46–53

Abstract: This study aimed to determine organ doses based on Monte Carlo (MC) simulations for individual paediatric patients undergoing chest-abdomen-pelvis computed tomography (CT) examinations and to evaluate correlations of organ doses with dose metrics. MC ... ...

Abstract	This study aimed to determine organ doses based on Monte Carlo (MC) simulations for individual paediatric patients undergoing chest-abdomen-pelvis computed tomography (CT) examinations and to evaluate correlations of organ doses with dose metrics. MC simulations were performed by inputting detailed descriptions of a CT scanner, scanning parameters and CT images of 51 paediatric patients aged from 0 to 10 years into the simulation software. Organ doses for six radiosensitive organs were determined from dose distribution images obtained as the simulation results. The correlations of organ doses with dose metrics such as volume CT dose index, size-specific dose estimates (SSDEs), and organ-specific SSDEs were evaluated from the corresponding coefficients of determination. Organ doses for ages of 0-1 and 1-5 years were 22%-32% lower than those for ages of 5-10 years. Organ doses exhibited higher linear correlations with SSDEs and organ-specific SSDEs, and can be easily estimated using the linear regression.
MeSH term(s)	Abdomen ; Adolescent ; Adult ; Aged ; Aged, 80 and over ; Benchmarking ; Child ; Child, Preschool ; Humans ; Infant ; Infant, Newborn ; Middle Aged ; Monte Carlo Method ; Pelvis/diagnostic imaging ; Phantoms, Imaging ; Radiation Dosage ; Tomography, X-Ray Computed ; Young Adult
Language	English
Publishing date	2021-12-07
Publishing country	England
Document type	Journal Article
ZDB-ID	225912-6
ISSN	1742-3406 ; 0144-8420
ISSN (online)	1742-3406
ISSN	0144-8420
DOI	10.1093/rpd/ncab157
Database	MEDical Literature Analysis and Retrieval System OnLINE

In stock of ZB MED Cologne/Königswinter

Zs.A 2009: Show issues

Location:
Je nach Verfügbarkeit (siehe Angabe bei Bestand)
bis Jg. 1994: Bestellungen von Artikeln über das Online-Bestellformular
Jg. 1995 - 2021: Lesesall (1.OG)
ab Jg. 2022: Lesesaal (EG)

Order via subito

This service is chargeable due to the Delivery terms set by subito. Orders including an article and supplementary material will be classified as separate orders. In these cases, fees will be demanded for each order.

Details ▾
- See ZB MED holdings
- Order with fees

Article ; Online: [Scientific Research Group Report: Nationwide Survey on Radiation Exposure of Pediatric CT Examination in Japan (2018)].

Takei, Yasutaka / Miyazaki, Osamu / Matsubara, Kosuke / Suzuki, Shoichi / Muramatsu, Yoshihisa / Fukunaga, Masaaki / Akahane, Masaaki

Nihon Hoshasen Gijutsu Gakkai zasshi

2022 Volume 78, Issue 4, Page(s) 372–380

Abstract: Purpose: To understand the latest pediatric computed tomography (CT) exposure required for the revision of national DRLs.: Methods: A questionnaire was sent to 409 facilities where the members of the Japanese Society of Radiological Technology and ... ...

Abstract	Purpose: To understand the latest pediatric computed tomography (CT) exposure required for the revision of national DRLs. Methods: A questionnaire was sent to 409 facilities where the members of the Japanese Society of Radiological Technology and the Japanese Society of Pediatric Radiology are enrolled. We investigated the imaging conditions, CTDI Results: In all, 43 facilities (11%) responded to our survey. multi detector-row CT (MDCT) systems were available in all surveyed facilities. More than 98% of the MDCT systems had more than 64 detector rows. The CTDI Conclusion: It is necessary to review the imaging protocol with the attending physician and radiologist and consider further optimization of medical exposure.
MeSH term(s)	Child ; Humans ; Japan ; Multidetector Computed Tomography ; Radiation Dosage ; Radiation Exposure ; Reference Values ; Surveys and Questionnaires
Language	Japanese
Publishing date	2022-03-03
Publishing country	Japan
Document type	Journal Article
ZDB-ID	2269092-X
ISSN	1881-4883 ; 0369-4305
ISSN (online)	1881-4883
ISSN	0369-4305
DOI	10.6009/jjrt.2022-1181
Database	MEDical Literature Analysis and Retrieval System OnLINE

Order via subito

Article ; Online: A new simpler image quality index based on body size for FDG-PET/CT.

Sagara, Hiroaki / Inoue, Kazumasa / Yaku, Hideki / Ohsawa, Amon / Mano, Chikara / Morita, Takahiro / Hiyama, Takashi / Muramatsu, Yoshihisa / Inaki, Anri / Fujii, Hirofumi

Nuclear medicine communications

2023 Volume 45, Issue 1, Page(s) 93–101

Abstract: Noise equivalent count density (NEC density ) is often used to evaluate the image quality of whole-body fluorodeoxyglucose tomography tests. However, this index is calculated using the patient volume, which is difficult to obtain at every facility. In ... ...

Abstract	Noise equivalent count density (NEC density ) is often used to evaluate the image quality of whole-body fluorodeoxyglucose tomography tests. However, this index is calculated using the patient volume, which is difficult to obtain at every facility. In this study, we proposed new image quality indices that can be evaluated at all facilities. In total, 94 patients were enrolled in the study. The correlations of patients' body weight and BMI with volume were examined. New image quality indices normalized by body weight and BMI were defined as NEC bw and NEC bmi , respectively. Correlations between NEC bw , NEC bmi , and NEC density were examined. Further, the correlations between these two new indices and visual scores were evaluated. Good correlations were observed between volume and body weight (r = 0.861, P < 0.001) and between volume and BMI (r = 0.728, P < 0.001). NEC bw and NEC bmi correlated well with NEC density (r = 0.954 for NEC bw and r = 0.897 for NEC bmi , P < 0.001). These correlations improved when the examined bed positions were set to the same number. Additionally, the correlations of visual scores with NEC bw and NEC bmi were similar to those between the visual score and NEC density . Our investigation indicated that the newly proposed image quality metrics, NEC bw and NEC bmi , were easily calculated and as useful as NEC density for evaluating image quality when subjects had similar physiques.
MeSH term(s)	Humans ; Fluorodeoxyglucose F18 ; Positron Emission Tomography Computed Tomography ; Positron-Emission Tomography/methods ; Body Weight
Chemical Substances	Fluorodeoxyglucose F18 (0Z5B2CJX4D)
Language	English
Publishing date	2023-10-30
Publishing country	England
Document type	Journal Article
ZDB-ID	758141-5
ISSN	1473-5628 ; 0143-3636
ISSN (online)	1473-5628
ISSN	0143-3636
DOI	10.1097/MNM.0000000000001787
Database	MEDical Literature Analysis and Retrieval System OnLINE

In stock of ZB MED Cologne/Königswinter

Zs.A 1577: Show issues

Location:
Je nach Verfügbarkeit (siehe Angabe bei Bestand)
bis Jg. 1994: Bestellungen von Artikeln über das Online-Bestellformular
Jg. 1995 - 2021: Lesesall (1.OG)
ab Jg. 2022: Lesesaal (EG)

Order via subito

Details ▾
- See ZB MED holdings
- Order with fees

Article ; Online: [Standards and Regulations Committee Reports].

Ishihara, Yotaro / Muramatsu, Yoshihisa / Okamoto, Kazuya / Takahashi, Junji / Yoshida, Mitsuhiro / Sato, Hiroshi

Nihon Hoshasen Gijutsu Gakkai zasshi

2021 Volume 77, Issue 12, Page(s) 1493–1514

MeSH term(s)	Reference Standards
Language	Japanese
Publishing date	2021-12-17
Publishing country	Japan
Document type	Journal Article
ZDB-ID	2269092-X
ISSN	1881-4883 ; 0369-4305
ISSN (online)	1881-4883
ISSN	0369-4305
DOI	10.6009/jjrt.2021_JSRT_77.12.1493
Database	MEDical Literature Analysis and Retrieval System OnLINE

Order via subito

Article ; Online: Evaluation of Apparent Noise on CT Images Using Moving Average Filters.

Fujii, Keisuke / Nomura, Keiichi / Imai, Kuniharu / Muramatsu, Yoshihisa / Tsushima, So / Ota, Hiroyuki

Journal of digital imaging

2021 Volume 35, Issue 1, Page(s) 77–85

Abstract: This study aims to devise a simple method for evaluating the magnitude of texture noise (apparent noise) observed on computed tomography (CT) images scanned at a low radiation dose and reconstructed using iterative reconstruction (IR) and deep learning ... ...

Abstract	This study aims to devise a simple method for evaluating the magnitude of texture noise (apparent noise) observed on computed tomography (CT) images scanned at a low radiation dose and reconstructed using iterative reconstruction (IR) and deep learning reconstruction (DLR) algorithms, and to evaluate the apparent noise in CT images reconstructed using the filtered back projection (FBP), IR, and two types of DLR (AiCE Body and AiCE Body Sharp) algorithms. We set a square region of interest (ROI) on CT images of standard- and obese-sized low-contrast phantoms, slid different-sized moving average filters in the ROI vertically and horizontally in steps of 1 pixel, and calculated the standard deviation (SD) of the mean CT values for each filter size. The SD of the mean CT values was fitted with a curve inversely proportional to the filter size, and an apparent noise index was determined from the curve-fitting formula. The apparent noise index of AiCE Body Sharp images for a given mAs value was approximately 58, 23, and 18% lower than that of the FBP, AIDR 3D, and AiCE Body images, respectively. The apparent noise index was considered to reflect noise power spectrum values at lower spatial frequency. Moreover, the apparent noise index was inversely proportional to the square roots of the mAs values. Thus, the apparent noise index could be a useful indicator to quantify and compare texture noise on CT images obtained with different scan parameters and reconstruction algorithms.
MeSH term(s)	Algorithms ; Humans ; Phantoms, Imaging ; Radiation Dosage ; Radiographic Image Interpretation, Computer-Assisted/methods ; Tomography, X-Ray Computed/methods
Language	English
Publishing date	2021-11-10
Publishing country	United States
Document type	Journal Article ; Research Support, Non-U.S. Gov't
ZDB-ID	1033897-4
ISSN	1618-727X ; 0897-1889
ISSN (online)	1618-727X
ISSN	0897-1889
DOI	10.1007/s10278-021-00531-5
Database	MEDical Literature Analysis and Retrieval System OnLINE

Full text online

Accessible to users with ZB MED library card

In stock of ZB MED Cologne/Königswinter

Zs.A 2941: Show issues

Location:
Je nach Verfügbarkeit (siehe Angabe bei Bestand)
bis Jg. 1994: Bestellungen von Artikeln über das Online-Bestellformular
Jg. 1995 - 2021: Lesesall (2.OG)
ab Jg. 2022: Lesesaal (EG)

Order via subito

Details ▾

Article ; Online: Correlation analysis of organ doses determined by Monte Carlo simulation with dose metrics for patients undergoing chest-abdomen-pelvis CT examinations.

Fujii, Keisuke / Nomura, Keiichi / Muramatsu, Yoshihisa / Goto, Takahiro / Obara, Satoshi / Ota, Hiroyuki / Tsukagoshi, Shinsuke

Physica medica : PM : an international journal devoted to the applications of physics to medicine and biology : official journal of the Italian Association of Biomedical Physics (AIFB)

2020 Volume 77, Page(s) 1–9

Abstract: Objectives: This study aimed to determine organ doses based on Monte Carlo (MC) simulations for individual patients undergoing routine adult chest abdomen-pelvis computed tomography (CT) examinations and to evaluate the correlations of organ doses with ... ...

Abstract	Objectives: This study aimed to determine organ doses based on Monte Carlo (MC) simulations for individual patients undergoing routine adult chest abdomen-pelvis computed tomography (CT) examinations and to evaluate the correlations of organ doses with patient size and dose metrics. Methods: MC simulations were performed by reading detailed descriptions of the CT scanner, scanning parameters, and CT images of phantoms and patients into the simulation software. The simulation models were validated by comparing the simulated doses with the doses measured by in-phantom dosimetry using radiophotoluminescent glass dosimeters and an adult anthropomorphic phantom, and organ doses for 80 patients were determined from the simulation results. To obtain patient size and dose metrics, body mass index and volume computed tomography dose index (CTDIvol) data were collected. Water equivalent diameter (WED) was calculated from the CT images of each patient. Size-specific dose estimates (SSDE) were calculated using CTDIvol and average WED over the scan range, and organ specific SSDE were calculated using the average CTDIvol and WED over each organ position. The correlations of organ doses with dose metrics were evaluated using coefficients of determination. Results: Organ doses increased with patient size, and the doses for obese were approximately two to three times higher than those for underweight patients. Organ doses exhibited stronger linear relationships with organ specific SSDE (R Conclusions: The linear regression fits between organ doses determined by MC simulation and organ-specific SSDE are valuable for simplified and accurate organ dose estimation for individual patients undergoing CT examinations.
MeSH term(s)	Abdomen ; Adult ; Benchmarking ; Humans ; Monte Carlo Method ; Pelvis/diagnostic imaging ; Phantoms, Imaging ; Radiation Dosage ; Tomography, X-Ray Computed
Language	English
Publishing date	2020-08-02
Publishing country	Italy
Document type	Journal Article
ZDB-ID	1122650-x
ISSN	1724-191X ; 1120-1797
ISSN (online)	1724-191X
ISSN	1120-1797
DOI	10.1016/j.ejmp.2020.07.016
Database	MEDical Literature Analysis and Retrieval System OnLINE

In stock of ZB MED Cologne/Königswinter

Zs.B 2941: Show issues

Location:
Je nach Verfügbarkeit (siehe Angabe bei Bestand)
bis Jg. 2021: Bestellungen von Artikeln über das Online-Bestellformular
ab Jg. 2022: Lesesaal (EG)

Order via subito

Details ▾
- See ZB MED holdings
- Order with fees

Article: [Report on performance evaluation group for CT-AEC].

Muramatsu, Yoshihisa

Nihon Hoshasen Gijutsu Gakkai zasshi

2005 Volume 61, Issue 8, Page(s) 1094–1103

MeSH term(s)	Image Processing, Computer-Assisted/instrumentation ; Image Processing, Computer-Assisted/methods ; Phantoms, Imaging ; Software ; Tomography, X-Ray Computed/instrumentation
Language	Japanese
Publishing date	2005-08-26
Publishing country	Japan
Document type	Journal Article ; Research Support, Non-U.S. Gov't ; Review
ZDB-ID	2269092-X
ISSN	1881-4883 ; 0369-4305
ISSN (online)	1881-4883
ISSN	0369-4305
DOI	10.6009/jjrt.kj00003943064
Database	MEDical Literature Analysis and Retrieval System OnLINE

Order via subito

Article: Investigation of the Section Thickness Measurement in Tomosynthesis by Thin Metal Plate Edge Method.

Ikeno, Kaoru / Akita, Tsunemichi / Hanai, Kozo / Muramatsu, Yoshihisa

Nihon Hoshasen Gijutsu Gakkai zasshi

2017 Volume 73, Issue 10, Page(s) 1007–1017

Abstract: When performing tomosynthesis, the section thickness needs to be set depending on a radiographic part and its diagnostic purpose. However, the section thickness in tomosynthesis has not been clearly defined and its measurement method has not been ... ...

Abstract	When performing tomosynthesis, the section thickness needs to be set depending on a radiographic part and its diagnostic purpose. However, the section thickness in tomosynthesis has not been clearly defined and its measurement method has not been established yet. In this study, we devised the alternative measurement method to diagnose the section thickness using an edge of thin metal plate, and compared with the simulation results, the wire and bead method reported in the previous papers. The tomographic image of the thin metal plate positioned on the table top inclining 30 degrees, which showed the edge spread function (ESF) of each tomographic height, was taken, and then the line spread function (LSF) was obtained by differentiating the ESF image. For the next, a profile curve was plotted by maximum values of LSF of each tomographic height, and a section thickness was calculated using the full width at half maximum (FWHM) of the profile curve. The edge method derived the section thickness close to the simulation results than the other methods. Further, the section thickness depends on the thickness of the metal plate and not the material. The thickness of the metal plate suitable for the evaluation of section thickness is 0.3 mm that is equivalent to pixel size of the flat panel detector (FPD). We conducted quantitative verification to establish the measurement method of the section thickness. The edge method is a useful technique as well as the wire and bead method for grasping basic characteristics of an imaging system.
Language	Japanese
Publishing date	2017
Publishing country	Japan
Document type	Journal Article
ZDB-ID	2269092-X
ISSN	1881-4883 ; 0369-4305
ISSN (online)	1881-4883
ISSN	0369-4305
DOI	10.6009/jjrt.2017_JSRT_73.10.1007
Database	MEDical Literature Analysis and Retrieval System OnLINE

Order via subito

Article ; Online: Radiation Dose Reduction for Computed Tomography Localizer Radiography Using an Ag Additional Filter.

Nomura, Keiichi / Fujii, Keisuke / Goto, Takahiro / Tsukagoshi, Shinsuke / Ota, Hiroyuki / Iwabuchi, Yuto / Suzuki, Hidenobu / Muramatsu, Yoshihisa / Kobayashi, Tatsushi

Journal of computer assisted tomography

2021 Volume 45, Issue 1, Page(s) 84–92

Abstract: Objective: This study aimed to assess the potential of an Ag additional filter attached to the bow tie filter of a computed tomography (CT) scanner to reduce the radiation dose in CT localizer radiography.: Methods: Radiation doses in CT localizer ... ...

Abstract	Objective: This study aimed to assess the potential of an Ag additional filter attached to the bow tie filter of a computed tomography (CT) scanner to reduce the radiation dose in CT localizer radiography. Methods: Radiation doses in CT localizer radiography with Cu and Ag additional filters were evaluated based on dose measurements and Monte Carlo simulations. Image quality evaluations of an adult torso phantom were performed, and the automatic exposure control performance was evaluated in terms of the water-equivalent thickness estimated from CT localizer radiographs. Results: With the Ag additional filter, effective doses were approximately 72% to 75% lower than those with the Cu additional filter. The image quality and water-equivalent thickness with the Ag additional filter were similar to those with the Cu additional filter. Conclusions: The Ag additional filter helped significantly reduce radiation doses in CT localizer radiography while maintaining image quality and performance.
MeSH term(s)	Adult ; Copper/adverse effects ; Equipment Design ; Humans ; Monte Carlo Method ; Phantoms, Imaging ; Radiation Dosage ; Radiographic Image Interpretation, Computer-Assisted ; Silver/adverse effects ; Tomography, X-Ray Computed/instrumentation ; Torso/diagnostic imaging
Chemical Substances	Silver (3M4G523W1G) ; Copper (789U1901C5)
Language	English
Publishing date	2021-01-20
Publishing country	United States
Document type	Journal Article
ZDB-ID	80392-3
ISSN	1532-3145 ; 0363-8715
ISSN (online)	1532-3145
ISSN	0363-8715
DOI	10.1097/RCT.0000000000001026
Database	MEDical Literature Analysis and Retrieval System OnLINE

In stock of ZB MED Cologne/Königswinter

Zs.A 1388: Show issues

Location:
Je nach Verfügbarkeit (siehe Angabe bei Bestand)
bis Jg. 1994: Bestellungen von Artikeln über das Online-Bestellformular
Jg. 1995 - 2021: Lesesall (1.OG)
ab Jg. 2022: Lesesaal (EG)

Order via subito

Details ▾
- See ZB MED holdings
- Order with fees

Article ; Online: Comprehensive evaluations of a prototype full field-of-view photon counting CT system through phantom studies.

Zhan, Xiaohui / Zhang, Ruoqiao / Niu, Xiaofeng / Hein, Ilmar / Budden, Brent / Wu, Shuoxing / Markov, Nicolay / Clarke, Cameron / Qiang, Yi / Taguchi, Hiroki / Nomura, Keiichi / Muramatsu, Yoshihisa / Yu, Zhou / Kobayashi, Tatsushi / Thompson, Richard / Miyazaki, Hiroaki / Nakai, Hiroaki

Physics in medicine and biology

2023 Volume 68, Issue 17

Abstract: ... ...

Abstract	Objective
MeSH term(s)	Humans ; Tomography, X-Ray Computed/methods ; Iodine ; Phantoms, Imaging ; Photons
Chemical Substances	Iodine (9679TC07X4)
Language	English
Publishing date	2023-08-14
Publishing country	England
Document type	Journal Article
ZDB-ID	208857-5
ISSN	1361-6560 ; 0031-9155
ISSN (online)	1361-6560
ISSN	0031-9155
DOI	10.1088/1361-6560/acebb3
Database	MEDical Literature Analysis and Retrieval System OnLINE

In stock of ZB MED Cologne/Königswinter

Zs.A 199: Show issues

Location:
Je nach Verfügbarkeit (siehe Angabe bei Bestand)
bis Jg. 1994: Bestellungen von Artikeln über das Online-Bestellformular
Jg. 1995 - 2021: Lesesall (1.OG)
ab Jg. 2022: Lesesaal (EG)

Order via subito

Details ▾
- See ZB MED holdings
- Order with fees

To top

More links

Kategorien

In stock of ZB MED Cologne/Königswinter

Order via subito

More links

Kategorien

Order via subito

More links

Kategorien

In stock of ZB MED Cologne/Königswinter

Order via subito

More links

Kategorien

Order via subito

Full text online

More links

Kategorien

In stock of ZB MED Cologne/Königswinter

Order via subito

More links

Kategorien

In stock of ZB MED Cologne/Königswinter

Order via subito

More links

Kategorien

Order via subito

More links

Kategorien

Order via subito

More links

Kategorien

In stock of ZB MED Cologne/Königswinter

Order via subito

More links

Kategorien

In stock of ZB MED Cologne/Königswinter

Order via subito