Abstract:
OBJECTIVES:The aim of this study was to assess the effectiveness of a model-based iterative reconstruction (MBIR) in improving image quality and diagnostic performance of ultralow-dose computed tomography (ULDCT) of the lung. MATERIALS AND METHODS:The institutional review board approved this study, and all patients provided written informed consent. Fifty-two patients underwent low-dose computed tomography (LDCT) (screening-dose, 50 mAs) and ULDCT (4 mAs) of the lung simultaneously. The LDCT images were reconstructed with filtered back projection (LDCT-FBP images) and ULDCT images were reconstructed with both MBIR (ULDCT-MBIR images) and FBP (ULDCT-FBP images). On all the 156 image series, objective image noise was measured in the thoracic aorta, and 2 blinded radiologists independently assessed subjective image quality. Another 2 blinded radiologists independently evaluated the ULDCT-MBIR and ULDCT-FBP images for the presence of noncalcified and calcified pulmonary nodules; LDCT-FBP images served as the reference. Paired t test, Wilcoxon signed rank sum test, and free-response receiver-operating characteristic analysis were used for statistical analysis of the data. RESULTS:Compared with LDCT-FBP and ULDCT-FBP, ULDCT-MBIR had significantly reduced objective noise (both P <; 0.001). Subjective noise on the ULDCT-MBIR images was comparable with that on the LDCT-FBP images but lower than that on the ULDCT-FBP images (P <; 0.001). Artifacts on ULDCT-MBIR images were more numerous than those on the LDCT-FBP images (P = 0.007) but fewer than those on the ULDCT-FBP images (P <; 0.001). Compared with the LDCT-FBP images, ULDCT-MBIR and ULDCT-FBP images showed reduced image sharpness (both P <; 0.001). All the ULDCT-MBIR images showed a blotchy pixelated appearance; however, the performance of ULDCT-MBIR was significantly superior to that of ULDCT-FBP for the detection of noncalcified pulmonary nodules (P = 0.002). The average true-positive fractions for significantly sized noncalcified nodules (≥4 mm) and small noncalcified nodules (<;4 mm) on the ULDCT-MBIR images were 0.944 and 0.884, respectively, when LDCT-FBP images were used as reference. All of the calcified nodules were detected by both the observers on both the ULDCT-MBIR and ULDCT-FBP images. CONCLUSION:As compared with FBP, MBIR enables significant reduction of the image noise and artifacts and also better detection of noncalcified pulmonary nodules on ULDCT of the lung. Compared with LDCT-FBP images, ULDCT-MBIR images showed significantly reduced objective noise and comparable subjective image noise. Almost all of the noncalcified nodules and all of the calcified nodules could be detected on the ULDCT-MBIR images, when LDCT-FBP images were used as the reference.
journal_name
Invest Radioljournal_title
Investigative radiologyauthors
Yamada Y,Jinzaki M,Tanami Y,Shiomi E,Sugiura H,Abe T,Kuribayashi Sdoi
10.1097/RLI.0b013e3182562a89subject
Has Abstractpub_date
2012-08-01 00:00:00pages
482-9issue
8eissn
0020-9996issn
1536-0210pii
00004424-201208000-00007journal_volume
47pub_type
杂志文章abstract:RATIONALE AND OBJECTIVES:To develop a computer-assisted analysis of complex joint motion based on standard fluoroscopic sequences. MATERIALS AND METHODS:Fluoroscopic sequences of 10 normal shoulders and 20 patients after total shoulder arthroplasty were recorded during abduction and adduction. The analysis of the shou...
journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/00004424-200202000-00004
更新日期:2002-02-01 00:00:00
abstract::The authors reexamined a suspected difference in the effects of clinical information upon detection of nodules vs. more diverse lesions by directly incorporating classification specificity into detection ROC analysis. Categorical prompts, correct for specific abnormalities, led to detection superior to unprompted read...
journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/00004424-198801000-00011
更新日期:1988-01-01 00:00:00
abstract:RATIONALE AND OBJECTIVES:New targeted microbubbles directed to the GPIIb IIIa receptor have been developed. The objective was to determine whether targeting microbubbles to clots would enhance ultrasound imaging. Systematic studies were designed to determine whether in vitro methodology is an acceptable predictor of in...
journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/00004424-200211000-00001
更新日期:2002-11-01 00:00:00
abstract::Over the past 120 years, continuous developments in medical imaging has improved diagnosis and treatment for many diseases and has thereby improved treatment outcome and quality of life of many patients. The number of computed tomography (CT) examinations is today increasing by 4% per year worldwide, for a total of ap...
journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/RLI.0000000000000696
更新日期:2020-09-01 00:00:00
abstract:RATIONALE AND OBJECTIVES:To develop a simple and robust helium3 polarization system dedicated to small animal imaging. To demonstrate the potential of helium3 imaging for pulmonary ventilation and perfusion studies. METHODS:A home-built polarization system based on spin-exchange technique was used. This system was app...
journal_title:Investigative radiology
pub_type: 杂志文章
doi:
更新日期:2003-06-01 00:00:00
abstract:OBJECTIVE:The aim of this study was to evaluate the potential of iterative metal artifact reduction (IMAR) for the improvement of computed tomography (CT)-based position emission tomography (PET) attenuation correction in the vicinity of metal implants and compare it with dual-energy-based metal artifact reduction stra...
journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/RLI.0000000000000306
更新日期:2017-01-01 00:00:00
abstract:OBJECTIVES:Comparison of intravenous Fenestra VC-enhanced computed tomography (CT) with gadopentetate dimeglumine and Ferucarbotran contrast-enhanced magnetic resonance imaging (MRI) for the in vivo imaging of hepatic ischemia/reperfusion injury (IRI) in a murine model. MATERIAL AND METHODS:After induction of hepatic ...
journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/RLI.0b013e318155aa2e
更新日期:2008-02-01 00:00:00
abstract:RATIONALE AND OBJECTIVES:The authors used magnetic resonance imaging (MRI) techniques to examine the effect of meningeal trauma produced by cisterna magna puncture on the integrity of the blood-cerebrospinal fluid barrier (BCB) in a rat model. METHODS:Intravenous gadolinium-DTPA (Gd-DTPA), a relaxation rate modifier w...
journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/00004424-199204000-00008
更新日期:1992-04-01 00:00:00
abstract:RATIONALE AND OBJECTIVES:Target-specific magnetic resonance (MR) contrast agents are being developed to improve the accuracy of MR imaging. The purpose of this study was to determine the mechanism of cell uptake, and modes of intracellular trafficking of a prototypical iron oxide label (RMA) used in the synthesis of so...
journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/00004424-199510000-00006
更新日期:1995-10-01 00:00:00
abstract:RATIONALE AND OBJECTIVES:The effect of varying exposure parameters on the detectability of a fracture with digital and conventional radiography were examined. METHODS:A macerated fractured skull was imaged by film-screen radiography (FSR) and digital storage phosphor radiography (DR) with various exposure values. Five...
journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/00004424-199303000-00010
更新日期:1993-03-01 00:00:00
abstract:OBJECTIVES:The purpose of this study was to assess whether the recently developed method of grating-based x-ray dark-field radiography can improve the diagnosis of pulmonary emphysema in vivo. MATERIALS AND METHODS:Pulmonary emphysema was induced in female C57BL/6N mice using endotracheal instillation of porcine pancr...
journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/RLI.0000000000000067
更新日期:2014-10-01 00:00:00
abstract::The authors evaluated double-blind comparative and open-label clinical trials in 1,186 patients who received ioversol to evaluate the safety and efficacy of ioversol, a new nonionic low-osmolality contrast medium, at iodine concentrations of 32%, 24%, and 16%. The results indicate that ioversol was well tolerated in a...
journal_title:Investigative radiology
pub_type: 临床试验,杂志文章
doi:10.1097/00004424-198906001-00020
更新日期:1989-06-01 00:00:00
abstract:RATIONALE AND OBJECTIVES:To evaluate the safety and pharmacokinetics of a newly developed MR contrast medium consisting of very small superparamagnetic iron oxide particles (VSOP) coated with citrate (VSOP-C184) in a clinical phase I trial. METHODS:A total of 18 healthy subjects received either VSOP-C184 (core diamete...
journal_title:Investigative radiology
pub_type: 临床试验,杂志文章,随机对照试验
doi:10.1097/01.rli.0000129472.45832.b0
更新日期:2004-07-01 00:00:00
abstract:RATIONALE AND OBJECTIVES:To compare the visibility and localization of extratemporal cortical lesions in extratemporal epilepsy by using curved reconstruction (CR) and three-dimensional surface rendering (3D SR) of 3D-acquired MR images and to study the degree of confidence with which localizations are made, particular...
journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/00004424-200104000-00005
更新日期:2001-04-01 00:00:00
abstract::Maximum likelihood estimation, assuming a binormal model, has been used extensively to estimate the area under receiver operating characteristic (ROC) curves and thus provide an index of diagnostic accuracy for the comparison of two imaging systems. However, in some instances, a degenerate data set results in a fitted...
journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/00004424-199007000-00016
更新日期:1990-07-01 00:00:00
abstract:OBJECTIVE:: This feasibility study was performed to assess whether dynamic contrast-enhanced ultrasound (CEUS) and transient arterial occlusion are able to detect alterations in the microvascular perfusion and arterial perfusion reserve in patients suffering from peripheral arterial disease (PAD) in comparison with hea...
journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/RLI.0b013e3182183a77
更新日期:2011-08-01 00:00:00
abstract::The large intestines of eight boxer dogs with canine histiocytic ulcerative colitis (CHUC) and 10 normal dogs were studied by in vivo angiography and postmortem microangiography. The vascular abnormalities were correlated with the gross and histologic pathology found at necropsy. The angiographic abnormalities were ...
journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/00004424-197505000-00005
更新日期:1975-05-01 00:00:00
abstract::Gadolinium was attached to antibodies and tested in vitro and in vivo for its effect on proton relaxation enhancement. Using the cyclic anhydride method, diethylenetriaminepentaacetic acid (DTPA) was attached to albumin, IgG and anti-CEA monoclonal antibody. Gadolinium (Gd) was then chelated to the protein complexes f...
journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/00004424-198510000-00008
更新日期:1985-10-01 00:00:00
abstract::Screening chronic hemodialysis patients (CHD) for acquired cystic disease of the kidneys (ACDK) and its complications (hemorrhage and neoplasm) has become accepted management. We evaluated patients on CHD as well as patients on chronic peritoneal dialysis (CPD) for ACDK. The kidneys of 80 chronic dialysis patients wer...
journal_title:Investigative radiology
pub_type: 杂志文章
doi:
更新日期:1987-09-01 00:00:00
abstract::"Satisfaction of search" (SOS) refers to the effect in which a second lesion remains undetected after detection of another lesion on the same radiograph. The objective of this study was to clarify our understanding of SOS by relating it to total time of inspection and time intervals before, between, and after discover...
journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/00004424-199107000-00003
更新日期:1991-07-01 00:00:00
abstract:RATIONALE AND OBJECTIVES:Studies describing the effects of radiographic contrast media (RCM) in leukocyte chemotaxis have been contradictory. No studies have been performed after in-vivo exposure. The authors assess the effect of RCM on leukocytes following in-vivo exposure. METHODS:Seventeen patients were studied aft...
journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/00004424-199401000-00012
更新日期:1994-01-01 00:00:00
abstract:RATIONALE AND OBJECTIVES:The authors used gadolinium (Gd) chelate as a T1, T2, and T2* enhancing agent in reperfused myocardial infarction to compare the appearance of reperfused myocardial infarction on spin echo and gradient echo magnetic resonance (MR) sequences. METHODS:Rats (n = 28) were subjected to reperfused m...
journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/00004424-199807000-00002
更新日期:1998-07-01 00:00:00
abstract:PURPOSE:We aimed to determine whether diffusion-weighted magnetic resonance imaging, by means of the apparent diffusion coefficient (ADC), is able to guide magnetic resonance-guided biopsy in patients fit for active surveillance (AS) and identify patients harboring high-grade Gleason components not suitable for AS. MA...
journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/RLI.0b013e31827b711e
更新日期:2013-03-01 00:00:00
abstract:RATIONALE AND OBJECTIVES:To study cellular mechanisms that cause contrast media nephropathy, an in vitro system for proximal and distal tubular cells has been established to evaluate the influence of x-ray contrast media on tubular function. METHODS:Confluent cell cultures of the two renal cell lines, proximal tubule ...
journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/00004424-199411000-00002
更新日期:1994-11-01 00:00:00
abstract::Diagnostic radiology is expanding, playing an increasingly central role in patient care, which heightens the importance of radiology teaching in undergraduate medical education. This study examined the impact of increased structure and systematic evaluation on student performance in a radiology elective. The evaluatio...
journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/00004424-198505000-00003
更新日期:1985-05-01 00:00:00
abstract::A technique to measure absolute arterial blood flow in ml/min has been developed utilizing software programs with high-speed digital recording for the off-line analysis of intra-arterial injections of contrast medium. Measurements of pulsatile flow in a phantom for a physical flow model showed that calculations with t...
journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/00004424-198503000-00017
更新日期:1985-03-01 00:00:00
abstract::The purpose of our investigation was to determine whether iopanoyl glucuronide, the major metabolite of iopanoic acid (Telepaque), undergoes hydrolysis by bacterial beta-glucuronidase in dogs. The conjugated compound was identified and quantitated by elemental analysis, fluorescent excitation analysis, thin-layer chro...
journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/00004424-197805000-00011
更新日期:1978-05-01 00:00:00
abstract:RATIONALE AND OBJECTIVES:Very small dextran-coated magnetite particles were developed. These particles can be used either as immunospecific contrast agents for MRI by coupling to antibodies or as an interstitial contrast agent. METHODS:The particles were synthesized from iron chloride/dextran solutions. Size was evalu...
journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/00004424-200009000-00006
更新日期:2000-09-01 00:00:00
abstract:OBJECTIVE:The aim of this study was to assess and compare the overall performance, reliability, variability, as well as the accuracy of diffusion tensor imaging (DTI) and fiber tracking metrics, for the muscles of the calf at 3 T and 7 T. MATERIALS AND METHODS:Ten volunteers (5 males; mean age, 29.1 ± 4.7 years), with...
journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/RLI.0000000000000508
更新日期:2019-01-01 00:00:00
abstract:RATIONALE AND OBJECTIVES:To present the results of two studies conducted to evaluate the pharmacokinetics and safety of iomeprol in healthy volunteers and in patients with various degrees of renal impairment. METHODS:In these two open-label, single-dose, phase I studies, a 50-mL dose of iomeprol 400 was administered i...
journal_title:Investigative radiology
pub_type: 临床试验,杂志文章
doi:10.1097/00004424-200106000-00002
更新日期:2001-06-01 00:00:00