Abstract:
RATIONALE AND OBJECTIVES:The authors report on the development and preliminary validation of a technique for measuring contrast-to-noise ratio (CNR) at all points along selected vessel segments in the original three-dimensional magnetic resonance angiography (MRA) dataset. METHODS:Contrast-to-noise ratio dependencies on flow rate, field of view, and flip angle were measured on images from a conventional time-of-flight MRA pulse sequence using constant flow in a branching vascular phantom. An estimate of the inherent variability of the technique was obtained from multiple scans of a flow phantom and a human volunteer. RESULTS:The overall standard deviation (SD) of the CNR was found to be approximately 6.1% of the average CNR value for the flow phantom study and 7.3% for the human study. Vessel CNR was found to increase with field of view and was found to become nonuniform for low flow rate and/or high flip angles. CONCLUSION:In general, such CNR measurements allow the investigation of the mechanism of signal loss and general technique optimization in MRA.
journal_name
Invest Radioljournal_title
Investigative radiologyauthors
Du Y,Parker DL,Davis WL,Blatter DDdoi
10.1097/00004424-199311000-00005subject
Has Abstractpub_date
1993-11-01 00:00:00pages
1004-9issue
11eissn
0020-9996issn
1536-0210journal_volume
28pub_type
杂志文章abstract:RATIONALE AND OBJECTIVES:Time-of-flight magnetic resonance angiography (TOF/MRA) is increasingly used to assess the nature and severity of stenotic blood vessels. Flow artifacts associated with high flows and/or narrow constrictions may confuse the interpretation of these studies. Accurate TOF/MRA evaluations demand an...
journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/00004424-199307000-00011
更新日期:1993-07-01 00:00:00
abstract::Prior to the formation of an intravenous digital subtraction angiography (IV-DSA) image, contrast medium passes through the lesser circulation and is diluted by the blood volume of the heart and lungs. If the contrast medium alone influences central blood volume or cardiac output, the shape of the resultant time-conce...
journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/00004424-198603000-00009
更新日期:1986-03-01 00:00:00
abstract::The authors present a numerical deconvolution technique to compensate for image degrading effects caused by scattered photons in radiographic chest images. Fourier transform techniques are used to deconvolve a shift invariant model of the two dimensional point spread response functions of the scattered radiation. This...
journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/00004424-198901000-00008
更新日期:1989-01-01 00:00:00
abstract:RATIONALE AND OBJECTIVES:The authors studied premenopausal, perimenopausal, and postmenopausal women to determine if ultrasound bone velocity (UBV) on proximal phalanges of women reflect bone changes related to gonadal status and age. METHODS:A total of 166 healthy women-64 postmenopausal women (mean age 58.7 +/- 9.4 ...
journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/00004424-199701000-00011
更新日期:1997-01-01 00:00:00
abstract:PURPOSE:Magnetic Resonance Imaging (MRI) has become the method of choice in the evaluation of patients with suspected cervical artery dissection (CAD). However, reliable identification of acute CAD might be impaired by the limited spatial resolution of standard 1.5 T MRI. In this preliminary study, we implemented a mul...
journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/01.rli.0000195836.57778.1f
更新日期:2006-02-01 00:00:00
abstract:OBJECTIVES:This clinical study investigated the pharmacokinetics and safety of gadobutrol, a magnetic resonance (MR) imaging extracellular contrast agent, in pediatric patients aged 2 to 17 years. MATERIALS AND METHODS:In this open-label, multicenter study, patients scheduled for routine contrast-enhanced MR imaging o...
journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/RLI.0b013e3181bfe2d2
更新日期:2009-12-01 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:OBJECTIVES:Altered systolic blood flow in the ascending aorta has been correlated with increased aortic growth in patients with bicuspid aortic valves (BAVs). We used conventional, 2-dimensional (2D) phase contrast magnetic resonance imaging (PC-MRI) to assess the relationship between altered flow and future growth in ...
journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/RLI.0000000000000064
更新日期:2014-10-01 00:00:00
abstract::Multiple intravenous injections of contrast media are used in radiology, but information regarding corresponding changes in the serum iodine concentrations and osmolality is lacking. We measured the changes in serum iodine concentration and serum osmolality in rabbits after a series of intravenous injections of contra...
journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/00004424-198703000-00007
更新日期:1987-03-01 00:00:00
abstract::Polylysine covalently linked to moieties of gadopentetate (Gd-DTPA), for use as a macromolecular blood pool marker for contrast material-enhanced magnetic resonance imaging (MRI), was characterized by means of physicochemical measurements and pharmacokinetics in rats and rabbits and compared with Gd-DTPA. Gd-DTPA-poly...
journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/00004424-199111000-00008
更新日期:1991-11-01 00:00:00
abstract:OBJECTIVES:To prospectively evaluate the image quality and diagnostic accuracy of magnetic resonance cholangiopancreatography (MRCP) at 3.0 T compared with that at 1.5 T used for patients. MATERIALS AND METHODS:This study was approved by our institutional review board, and informed consent was obtained from all patien...
journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/RLI.0b013e3181b4c0ae
更新日期:2009-09-01 00:00:00
abstract:RATIONALE AND OBJECTIVES:Our purpose was to validate contrast-enhanced computed tomography (CECT)-derived quantitative measures of perfusion and permeability against gold standard techniques of fluorescent microspheres and Evan's Blue dye, respectively. MATERIALS AND METHODS:Normal and tumor-bearing (R3230AC) Fischer ...
journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/01rli.0000124456.82985.35
更新日期:2004-06-01 00:00:00
abstract::Twenty-six patients who had received 43 grafts were studied before and after coronary artery vein bypass surgery. Cine ventriculograms taken in the right anterior oblique projection were analyzed and regional ejection fractions calculated. Single and multiple grafts were considered separately as were thrombosed and pa...
journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/00004424-197705000-00001
更新日期:1977-05-01 00:00:00
abstract:OBJECTIVE:As an imaging modality for follow-up during continuous or repeated hepatic arterial infusion chemotherapy using a hepatic intra-arterial indwelling catheter, the usefulness of CT while infusing contrast through the indwelling catheter (reservoir port) was examined. METHODS:Using reservoir ports implanted in ...
journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/00004424-199912000-00003
更新日期:1999-12-01 00:00:00
abstract::Magnetic resonance spectroscopy (MRS) has been most extensively applied to the study of animal models and not humans. The major reason for this extensive animal research is due to the nature of the early magnetic resonance high-field magnets, which only permitted the study of isolated cells, tissues, or small animals....
journal_title:Investigative radiology
pub_type: 杂志文章,评审
doi:10.1097/00004424-198912000-00004
更新日期:1989-12-01 00:00:00
abstract:OBJECTIVES:The safety of nonionic contrast agents with that of ionic iodinated contrast agents in children is compared. METHODS:A comprehensive literature search was conducted to identify all publications on the safety profile of nonionic contrast agents administered intravenously to children. This information was com...
journal_title:Investigative radiology
pub_type: 杂志文章,评审
doi:10.1097/00004424-199311001-00027
更新日期:1993-11-01 00:00:00
abstract::Effectiveness of terbutaline, a potent uterine muscle relaxant, for differentiation of temporary and anatomic interstitial fallopian tube obstruction (IFTO) at hysterosalpingography (HSG) was explored. In 43 IFTO evaluated, HSG after terbutaline showed patency in only one of 16 tubes in which IFTO was caused by spasm ...
journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/00004424-198803000-00010
更新日期:1988-03-01 00:00:00
abstract::Trypan blue and 197HgCl2 were used as markers of the increased leakage through the blood-brain barrier which developed after selective injection of different contrast media formulations into the internal carotid arteries of rabbits. Interest was focused on a new, experimental, nonionic medium (C-29) and possible effec...
journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/00004424-197907000-00007
更新日期:1979-07-01 00:00:00
abstract:MATERIALS AND METHODS:Stenotic kidney (STK) and contralateral kidney magnetization transfer ratios (MTRs; Mt/M0) were measured at 3.0-T magnetic resonance imaging, at offset frequencies of 600 and 1000 Hz, before and 1 month post-PTRA in 7 RVD pigs. Stenotic kidney MTR was correlated to renal perfusion, renal blood flo...
journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/RLI.0000000000000711
更新日期:2021-02-01 00:00:00
abstract:RATIONAL AND OBJECTIVES:The purpose of this study was to evaluate the effects of variation in design parameters on the resultant radial force. We evaluated the influence of wire gauge, leg length, and number of bends on the radial force produced by z stents and compared these with radial forces produced by commercial s...
journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/00004424-200109000-00004
更新日期:2001-09-01 00:00:00
abstract:PURPOSE:The relaxivities of 3 macrocyclic gadolinium-based contrast agents (GBCAs) were determined in human plasma and blood under standardized and clinically relevant laboratory conditions. METHODS:The T1 relaxivity, r1, was determined in human plasma at 1.5, 3, and 7 T, and in human blood at 3 T at 37°C in phantoms ...
journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/RLI.0000000000000577
更新日期:2019-09-01 00:00:00
abstract:RATIONALE AND OBJECTIVES:The authors differentiate acute tubular necrosis from transplant rejection in patients with delayed kidney graft function using gadolinium (Gd)-DTPA enhanced magnetic resonance (MR) imaging. METHODS:Twenty-four patients after renal transplantation (10 with normal graft function, 14 with delaye...
journal_title:Investigative radiology
pub_type: 临床试验,杂志文章
doi:10.1097/00004424-199606000-00009
更新日期:1996-06-01 00:00:00
abstract:RATIONALE AND OBJECTIVES:High signal intensity in the basal ganglia on T1-weighted MR imaging has been reported in chronic manganese (Mn) poisoning. However, the exact meaning of the high signal intensity remains unclear: does it result from Mn itself, secondary pathologic changes of the brain tissue, or both? The goal...
journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/00004424-199906000-00001
更新日期:1999-06-01 00:00:00
abstract::Surgical resection is the standard of care for colorectal metastases isolated to the liver. However, only 10-25% of the patients are eligible for resection because of extent and location of the disease in the liver or concurrent medical conditions. Image-guided radiofrequency (RF) ablation is a minimally invasive tech...
journal_title:Investigative radiology
pub_type: 杂志文章,评审
doi:10.1097/00004424-200411000-00007
更新日期:2004-11-01 00:00:00
abstract:PURPOSE:The aim of this study was to identify the signal intensity (SI) changes in the dentate nucleus (DN) and the globus pallidus (GP) on unenhanced T1-weighted magnetic resonance (MR) images after multiple administration of gadolinium-based contrast agents (GBCAs) in children and compare those changes between linear...
journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/RLI.0000000000000436
更新日期:2018-04-01 00:00:00
abstract::The cerebrovascular toxicity of three water-soluble contrast agents with a low hypertonicity (metrizamide, ioxaglate, iopamidol) was tested. Blood-brain barrier damage after carotid injection was assessed using 32P autoradiography and fluorescent microscopy after Evans blue staining. The damage to carotid endothelium ...
journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/00004424-198011001-00058
更新日期:1980-11-01 00:00:00
abstract::Receiver operating characteristic (ROC) analysis has been used in a broad variety of medical imaging studies during the past 15 years, and its advantages over more traditional measures of diagnostic performance are now clearly established. But despite the essential simplicity of the approach, workers in the field ofte...
journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/00004424-198903000-00012
更新日期:1989-03-01 00:00:00
abstract:RATIONALE AND OBJECTIVES:In contrast-enhanced dual-energy subtraction imaging 2 images acquired postcontrast media administration at different energies are subtracted to highlight structures hidden in the absence of contrast media. X-ray spectra of the newly developed digital full-field mammography units (GE Senographe...
journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/01.RLI.0000077124.24140.bd
更新日期:2003-09-01 00:00:00
abstract::A radiographic method for use in the closed-chest dog is described which allows the quantitation of segmental mechanical performance. Previous work has shown that the area of the pressure-length loop (an approximation of a stress-strain integral) is a useful measure of the mechanical work performed by a segment of myo...
journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/00004424-197611000-00010
更新日期:1976-11-01 00:00:00
abstract:RATIONALE AND OBJECTIVES:Air microemboli may damage the cerebral microvasculature. The aim of this study was to evaluate the safety of ultrasound contrast agents composed of air microspheres with regard to cerebral damage when administered into the arterial system (ie, when not filtered by the capillary system of the l...
journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/00004424-199803000-00001
更新日期:1998-03-01 00:00:00