Abstract:
RATIONALE AND OBJECTIVES:Density of trabecular bone structures in human heel bones was assessed by 3D magnetic resonance (MR) gradient echo imaging (GEI) with multiple echoes. Different spatial resolutions were applied to investigate the influence of the pixel size on signal characteristics in GEI and to find suitable measuring parameters for a maximum correlation between GEI and bone mineral density obtained by quantitative computed tomography (QCT). METHODS:Thirty-five patients aged 31 to 65 years with suspected osteoporosis underwent MR and QCT examinations of the heel bones. The MR protocol included 3D GEI with three echo times (TE1 = 9.3, TE2 = 27.9, and TE3 = 46.5 ms) and isotropic pixel sizes of (0.6 mm)3, (1.2 mm)3, and (2.4 mm)3. Several subregions in the heel bones were analyzed. For determination of signal reduction with increasing TE, signal intensity ratios were calculated pixelwise from images with TE2/TE1 and TE3/TE1. RESULTS:All examinations showed that the T2*-related signal decrease was more pronounced for lower spatial resolution. In the dorsal part of the heel bones, the correlation between signal ratios in GEI and QCT-based bone mineral density values was between r = -0.86 for a spatial resolution of (0.6 mm)3 and r = -0.73 for (2.4 mm)3. Areas with low trabecular density in the ventral part of the heel bones showed clearly lower correlation coefficients (-0.65 < r < -0.67). CONCLUSIONS:Spatial resolution in 3D GEI clearly influences the T2*-related signal characteristics. Despite measuring different physical properties of spongy bone by GEI and QCT, a relatively high correlation between GEI with small pixel sizes and QCT was obtained in the dorsal part of the heel bones, but not in the ventral part with partly thickened trabeculae and irregular distribution. However, standardized measuring protocols with preferably small pixel sizes (as low as [0.6 mm]3) should be applied, and correlation curves must be determined, dependent on the actual bone marrow site, before clinical routine MR osteodensitometry becomes possible.
journal_name
Invest Radioljournal_title
Investigative radiologyauthors
Machann J,Schnatterbeck P,Raible A,Lutz O,Claussen CD,Schick Fdoi
10.1097/00004424-200007000-00001keywords:
subject
Has Abstractpub_date
2000-07-01 00:00:00pages
393-400issue
7eissn
0020-9996issn
1536-0210journal_volume
35pub_type
杂志文章abstract:RATIONALE AND OBJECTIVES:The authors detect activation in the auditory cortex during cochlear electrical stimulation in deaf patients using functional magnetic resonance (MR) imaging. METHODS:Stimulating electrode was inserted gently under local anesthesia close to the round window membrane of the cochlea in seven coc...
journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/00004424-199705000-00007
更新日期:1997-05-01 00:00:00
abstract::Urine samples were collected from 200 subjects undergoing intravenous pyelography. The urine histamine levels were compared with those of 132 normal control subjects, 11 subjects with systemic mastocytosis, six subjects with idiopathic anaphylaxis, and ten subjects experiencing mild anaphylactic reactions during aller...
journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/00004424-198403000-00007
更新日期:1984-03-01 00:00:00
abstract:RATIONALE AND OBJECTIVES:The author analyzes findings of consistency of rotator-cuff calcifications found at ultrasound (US)-guided needle treatment compared with findings of plain radiography, US, and computed tomography (CT). METHODS:Twenty patients had rotator-cuff calcifications (mean diameter, 1.5 cm; range, 1.1-...
journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/00004424-199605000-00010
更新日期:1996-05-01 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:The vasoconstriction of the renal arteries is frequently considered as a crucial factor for radiocontrast-induced nephropathy. A direct effect of iodinated radiographic contrast medium (RCM) on vascular smooth muscle is supposed to be one component of the vascular response. We studied the effec...
journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/00004424-200208000-00005
更新日期:2002-08-01 00:00:00
abstract:OBJECTIVES:The purpose of this study was to develop and validate a computer-aided diagnosis (CAD) tool for automatic classification of pulmonary nodules seen on low-dose computed tomography into solid, part-solid, and non-solid. MATERIALS AND METHODS:Study lesions were randomly selected from 2 sites participating in t...
journal_title:Investigative radiology
pub_type: 临床试验,杂志文章,多中心研究,随机对照试验
doi:10.1097/RLI.0000000000000121
更新日期:2015-03-01 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:RATIONALE AND OBJECTIVES:Magnetic resonance microscopy (MRM) has evolved from a technical curiosity to a tool with which researchers can study important disease models. But MRM is not simply an extension of clinical magnetic resonance imaging. In this article, the unique adaptations of MRM required in the study of caro...
journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/00004424-199409000-00004
更新日期:1994-09-01 00:00:00
abstract:OBJECTIVES:The authors assessed the relative efficacy of conventional and digital storage-phosphor radiographs for the detection of skull fractures. METHODS:Fifty conventional film-screen radiographs (FSR) and 50 digital storage-phosphor radiographs (DR) with 66 fractures were compared. Five radiologists evaluated ima...
journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/00004424-199308000-00005
更新日期:1993-08-01 00:00:00
abstract::The potential of magnetic resonance imaging (MRI) quantification of calcium for the evaluation of pulmonary nodules was investigated in simulated nodules. Calcium salts do not contain mobile protons and thus have no signal on MR proton images. To determine whether the absence of signal from partially calcified nodules...
journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/00004424-198711000-00001
更新日期:1987-11-01 00:00:00
abstract::The microangiographic anatomy of the cat's eye is presented. The characteristic vascular pattern of each of the three distinct circulations, retinal choroidal, and ciliary is described and illustrated. ...
journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/00004424-197501000-00007
更新日期:1975-01-01 00:00:00
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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:Contrast-enhanced ultrasound imaging is increasingly being used in the clinic for assessment of tissue vascularity. The purpose of our study was to evaluate the effect of different contrast administration parameters on the in vivo ultrasound imaging signal in tumor-bearing mice using a maximum intensity pers...
journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/RLI.0b013e3181f9202d
更新日期:2011-03-01 00:00:00
abstract:RATIONALE AND OBJECTIVES:To assess the potential of magnetic resonance imaging (MRI) for evaluating the evolution of tumor necrosis, the authors evaluated 28 VX2 carcinomas inoculated in the thigh muscles of rabbits. METHODS:MRI of VX2 carcinomas at 2.0 T was done with spin-echo technique 1 week (14 tumors) and 3 week...
journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/00004424-199301000-00010
更新日期:1993-01-01 00:00:00
abstract::The results of an in vitro mixed hemadsorption (MHA) assay predicted the success of in vivo tumor localization using a radioiodinated, monoclonal, IgG1 antibody (A2) with reactivity to the human bladder carcinoma cell line RT4. In vitro, murine monoclonal antibodies A2 and G6, demonstrated reactivity to RT4 with titer...
journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/00004424-198411000-00011
更新日期:1984-11-01 00:00:00
abstract:RATIONALE AND OBJECTIVES:To evaluate the imaging characteristics of various iliac artery stents and stent-grafts in a multislice, computed tomography angiography (MSCTA) phantom study. METHODS:Twelve types of stents and three stent-grafts made of different materials (steel, nitinol, tantalum, cobalt-based alloy) were ...
journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/00004424-200112000-00004
更新日期:2001-12-01 00:00:00
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:RATIONALE AND OBJECTIVES:The basic characteristics of BR1, a novel echo contrast agent based on stabilized sulfur hexafluoride (SF6) microbubbles have been evaluated. METHODS:The authors determined the physicochemical properties (bubble concentration, bubble size distribution, resistance to pressure, and stability) an...
journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/00004424-199508000-00001
更新日期:1995-08-01 00:00:00
abstract::French physicians must obtain their patient's consent before carrying out an action that interferes with the patient's corporal integrity. The doctor must use simple, approximate, intelligent, and honest words that help the patient to reach the indispensable decision. Proof of lack of consent lies with the patient. Th...
journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/00004424-198809001-00006
更新日期:1988-09-01 00:00:00
abstract::Gastrografin and Amipaque with identical iodine content and flavoring were orally administered in 100 ml doses to 10 healthy volunteers in a double-blind crossover study. The nonionic Amipaque has only about one third of the osmolality of Gastrografin, and draws less fluid into the bowel lumen. Consequently there is l...
journal_title:Investigative radiology
pub_type: 临床试验,杂志文章
doi:10.1097/00004424-197811000-00008
更新日期:1978-11-01 00:00:00
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journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/00004424-200012000-00007
更新日期:2000-12-01 00:00:00
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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:OBJECTIVES:The aim of this study was to quantify image quality gains of a moving coronary plaque phantom using dual-source computed tomography (DSCT) providing 83 milliseconds temporal resolution in direct comparison to 64 slice single-source multidetector CT (MDCT) with a temporal resolution of 165 milliseconds. MATE...
journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/01.rli.0000254409.79193.96
更新日期:2007-03-01 00:00:00
abstract:OBJECTIVES:To investigate image quality and interstudy reproducibility of aortic atherosclerosis imaging at 1.5 T, and to explore the impact of parallel imaging techniques at 3 T. MATERIALS AND METHODS:Institutional review board approval and informed consent were obtained. Thirty-two subjects (20 normal, 12 patients w...
journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/RLI.0b013e318181538a
更新日期:2008-09-01 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
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journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/RLI.0b013e3181a8b015
更新日期:2009-08-01 00:00:00
abstract::Observation of the relaxivity of MRI contrast media over a wide range of magnetic fields is not only necessary for predicting their efficiency at any field but also compulsory for understanding and improving their mechanisms of action. The best experimental approach to this problem is the field cycling method, which a...
journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/00004424-198809001-00047
更新日期:1988-09-01 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: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
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journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/RLI.0b013e31828a012d
更新日期:2013-09-01 00:00:00