A5109066862- Medical Imaging Techniques and Applications
- Radiation Dose and Imaging
- Advanced X-ray and CT Imaging
- Radiomics and Machine Learning in Medical Imaging
- Lung Cancer Diagnosis and Treatment
- Digital Radiography and Breast Imaging
- Advanced Radiotherapy Techniques
- MRI in cancer diagnosis
- Glioma Diagnosis and Treatment
- Radiology practices and education
- Cardiac Imaging and Diagnostics
- Occupational and environmental lung diseases
- Engineering Applied Research
- Renal cell carcinoma treatment
- Traumatic Brain Injury and Neurovascular Disturbances
- Lymphoma Diagnosis and Treatment
- Hepatocellular Carcinoma Treatment and Prognosis
- Brain Tumor Detection and Classification
- Radioactivity and Radon Measurements
- Advanced X-ray Imaging Techniques
- Advanced MRI Techniques and Applications
National Cancer Center Hospital East
2015-2025
National Cancer Centre Japan
2023
Tokushima University
2020
National Center For Child Health and Development
2017
Toyama University Hospital
2010
National Hospital Organization
2008
National Cancer Center
1995-1997
Dokkyo Medical University Saitama Medical Center
1994
Dokkyo University
1994
Purpose The image noise and quality of a prototype ultra-high-resolution computed tomography (U-HRCT) scanner was evaluated compared with those conventional high-resolution CT (C-HRCT) scanners. Materials Methods This study approved by the institutional review board. A U-HRCT 0.25 mm x 4 rows operating at 120 mAs used. C-HRCT images were obtained using 0.5 16 or 64 detector-row 150 mAs. Images from both scanners reconstructed 0.1-mm intervals; slice thickness for For scanners, display field...
Objective. Photon counting CT (PCCT) has been a research focus in the last two decades. Recent studies and advancements have demonstrated that systems using semiconductor-based photon detectors (PCDs) potential to provide better contrast, noise spatial resolution performance compared conventional scintillator-based systems. With multi-energy threshold detection, PCD can simultaneously energy measurement enable material decomposition for spectral imaging. In this work, we report evaluation of...
OBJECTIVE. We assessed the local recurrence rate after a single targeted transarterial oily chemoembolization for small hepatocellular carcinoma with unified helical CT and angiography system analyzed factors affecting survival Cox proportional hazards model.
This is a preliminary analysis of one the secondary endpoints in prospective study cohort. The aim this to assess image quality and diagnostic confidence for lung cancer CT images generated by using cadmium-zinc-telluride (CZT)-based photon-counting-detector-CT (PCD-CT) comparing these super-high-resolution (SHR) with conventional normal-resolution (NR) images. Twenty-five patients (median age 75 years, interquartile range 66-78 18 men 7 women) 29 nodules overall (including two 4 2 nodules,...
Purpose: To develop a chest phantom for determining the optimal scan conditions computed tomography (CT) screening. Methods: The basic structure of is an arms-elevated-positioned anthropomorphic phantom. internal includes simulated tumors (which are assumed to be target lesions CT screening examinations) placed at levels lung apex, bifurcation trachea, and base both lungs. image contrast taken as difference in value specified 1 2 values: Δ270 Δ100. An opening placement dosimeter provided on...
Abstract Objective Recently, the national diagnostic reference levels (DRLs) in Japan were revised as DRLs 2020, wherein body weight-based injection dose optimization positron emission tomography/computed tomography using 18 F-fluoro-2-deoxy-D-glucose ( F-FDG PET/CT) was first proposed. We retrospectively investigated usefulness of this method improving image quality and reducing radiation dose. Methods A total 1,231 patients enrolled study. fixed 240 MBq administered to 624 patients, a...
The purpose of this study is to assess the relative influence noise and artifact in detecting lung nodules on low dose computed tomographic (CT) screening.We develop computer-simulation technique that allows tube current simulation virtual nodule insertion any CT images. uses a reduction model adds random Gaussian distribution existing projection data. are generated using dedicated tool with same scanner geometry.The coefficient correlations between contrast-to-noise ratio actual scan...
The objective of this research is to calculate the organ equivalent dose and effective from scanning conditions at 165 centers in Japan using computed tomography (CT) Dose software compare results with CT index volume (CTDIvol), length product (DLP) size-specific estimates (SSDE) validate usefulness SSDE. CTDIvol DLP were significantly lower infants than children (p < 0.05). No significant differences found bone marrow for torso between > 0.05), head higher difference was SSDE Organ doses...
Objective This study aimed to assess the potential of an Ag additional filter attached bow tie a computed tomography (CT) scanner reduce radiation dose in CT localizer radiography. Methods Radiation doses radiography with Cu and filters were evaluated based on measurements Monte Carlo simulations. Image quality evaluations adult torso phantom performed, automatic exposure control performance was terms water-equivalent thickness estimated from radiographs. Results With filter, effective...
We carried out a nationwide questionnaire survey of pediatric computed tomography (CT) in 339 facilities. Most facilities operated multi detector-row CT (MDCT), and over half 64, 128, 256 320-slice MDCT. In 32% facilities, protocols were set taking image quality dose into consideration. However, the other may not be optimized because there is no clear standard for or dosage examinations Japan. To promote optimization protocols, we regard it as an urgent task to establish diagnostic reference...
A new technical standard for X-ray computed tomography (CT) has been published by the National Electrical Manufacturers Association (NEMA) that allows Alert Value and Notification cumulative dose to be configurable CT systems operators in conjunction with XR-25 (Dose check) standard. In this study, a decision method of Values reducing radiation was examined using index registry (DIR) system, during 122 continuous days from August 1, 2012 November 30, 2012. images were obtained Discovery...
A survey on recognition, utilization, and evaluation for diagnostic reference levels (DRLs) after establishing Japan DRLs 2015 in the field of X-ray computed tomography (CT) was conducted members Japanese Society Radiological Technology using web-based questionnaire system. The consisted provincial branches to which respondents belong, their occupation, years professional experience, experience CT section, recognition DRLs, utilization section. Each item had one eight questions. total 369...
The performance of two PET examinations, one using L-[methyl-¹¹C] methionine (MET) and 2-[¹⁸F] fluoro-2-deoxy-D-glucose (FDG), on the same day may offer a clinical advantage for investigation brain tumors or other lesions. purpose this study was to investigate effect positron cross-talk (PCT) determine optimal protocol MET FDG day.The participants comprised 62 patients with head neck cancer. We focused high physiological uptake in liver evaluated PCT muscle. Three FDG-PET scans [one: whole...
When performing tomosynthesis, the section thickness needs to be set depending on a radiographic part and its diagnostic purpose. However, in tomosynthesis has not been clearly defined measurement method established yet. In this study, we devised alternative diagnose using an edge of thin metal plate, compared with simulation results, wire bead reported previous papers. The tomographic image plate positioned table top inclining 30 degrees, which showed spread function (ESF) each height, was...
本研究ではAxial像を中心に, ヘリカルCTにおける再構成間隔と腫瘤性陰影の描出能の関係をコントラスト分解能の違いから述べた.ヘリカルCTでは, 検査目的に応じて最適な再構成間隔を定めることで, 体軸方向に対する情報量をいかに効率良く, かつ最大限に得るかが重要なスキャン条件の選択となる.今後, 3次元画像表示への対応も含めて最適再構成間隔の設定基準を定めて行きたい.
To assist in the selection of complicated computed tomography (CT) scan protocols and to obtain stable image SD values, prototype "Scan Plan Simulator" software with following functions was developed evaluated. 1) The value that will be obtained actual scanning is estimated by entering patient's body size protocol, after which a simulated displayed so can checked. exposure dose also Scan Simulator. 2) appropriate tube current automatically set required value. We evaluated accuracy Simulator...
The section sensitivity profile (SSP) is adequate to express the properties of helical CT images. Although SSP measurement has been performed only at center imaging field, we applied it off-center positions using a metal bead and controlled tracking technique. experimental results indicated that curves vary in field according relative position x-ray focus. were agreement with computer simulations.