Abstract:
OBJECTIVE:With the introduction of ultrashort echo time (UTE) sequences solid polymeric materials might become visible on clinical whole-body magnetic resonance (MR) scanners. The aim of this study was to characterize solid polymeric materials typically used for instruments in magnetic resonance guided interventions and implants. Relaxation behavior and signal yield were evaluated on a 3-Tesla whole-body MR unit. MATERIALS AND METHODS:Nine different commonly used solid polymeric materials were investigated by means of a 3-dimensional (3D) UTE sequence with radial k-space sampling. The investigated polymeric samples with cylindrical shape (length, 150 mm; diameter, 30 mm) were placed in a commercial 8-channel knee coil. For assessment of transverse signal decay (T2*) images with variable echo times (TE) ranging from 0.07 milliseconds to 4.87 milliseconds were recorded. Spin-lattice relaxation time (T1) was calculated for all MR visible polymers with transverse relaxation times higher than T2* = 300 mus using an adapted method applying variable flip angles. Signal-to-noise ratio (SNR) was calculated at the shortest achievable echo time (TE = 0.07 milliseconds) for standardized sequence parameters. All relaxation times and SNR data are given as arithmetic mean values with standard deviations derived from 5 axially oriented slices placed around the isocenter of the coil and magnet. RESULTS:Six of the 9 investigated solid polymers were visible at TE = 0.07 milliseconds. Visible solid polymers showed markedly different SNR values, ie, polyethylene SNR = 1146 +/- 41, polypropylene SNR = 60 +/- 6. Nearly mono-exponential echo time dependent signal decay was observed: Transverse relaxation times differed from T2*=36 +/- 5 mus for polycarbonate to T2*=792 +/- 7 mus for polyvinylchloride (PVC). Two of the investigated solid polymers were applicable to T1 relaxation time calculation. Polyurethane had a spin-lattice relaxation time of T1 = 172 +/- 1 milliseconds, whereas PVC had T1 = 262 +/- 7 milliseconds, respectively. CONCLUSIONS:A variety of solid polymers can be visualized by means of clinical whole-body MR scanners and 3D ultrashort echo time (UTE) sequences. The investigated polymers differ substantially in signal yield, signal-decay, and spin-lattice relaxation time. The knowledge of the signal behavior of solid polymers on whole-body clinical MR scanners may help to select suitable polymeric materials for instruments and implants which are visible using UTE sequences.
journal_name
Invest Radioljournal_title
Investigative radiologyauthors
Springer F,Martirosian P,Schwenzer NF,Szimtenings M,Kreisler P,Claussen CD,Schick Fdoi
10.1097/RLI.0b013e318188601fsubject
Has Abstractpub_date
2008-11-01 00:00:00pages
802-8issue
11eissn
0020-9996issn
1536-0210pii
00004424-200811000-00007journal_volume
43pub_type
杂志文章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:RATIONALE AND OBJECTIVES:To compare the diagnostic efficacy of a standard dose of MRI contrast agent in the evaluation of primary brain tumors and metastases using a high-field 3 tesla MR unit versus a 1.5 tesla MR unit. METHODS:Sixteen patients with brain tumors were examined at both field strengths using identical a...
journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/00004424-200203000-00003
更新日期:2002-03-01 00:00:00
abstract:OBJECTIVES:Transcatheter arterial embolization (TAE) is used for the treatment of patients with malignant liver tumors. However, the proangiogenesis effect of TAE-associated hypoxia has not been adequately studied. The goal of this study was to determine angiogenic activity in tumors subjected to TAE by evaluating the ...
journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/01.rli.0000209663.00629.8a
更新日期:2006-06-01 00:00:00
abstract:OBJECTIVE:Hydration is widely accepted as an effective measure to prevent contrast media (CM)-induced acute kidney injury (AKI). Whether bicarbonate (NaHCO₃) infusion has a greater effect than saline is disputed. Effective prevention of CM-induced AKI by NaHCO₃ has been found by several clinical trials. However, others...
journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/RLI.0b013e31822311a9
更新日期:2011-11-01 00:00:00
abstract:OBJECTIVE:To evaluate the feasibility of adenosine-stress dynamic myocardial volume perfusion imaging with second generation dual source computed tomography (CT) for the qualitative and quantitative assessment of myocardial blood flow (MBF) compared with stress perfusion and viability magnetic resonance imaging (MRI). ...
journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/RLI.0b013e3181dfa2f2
更新日期:2010-06-01 00:00:00
abstract:RATIONALE AND OBJECTIVES:Because of the greatly increased cost of nonionic, low-osmolar contrast material, some practitioners reserve its use for patients at high risk for an adverse contrast reaction. The authors attempt to evaluate the proportion of low-risk outpatients--when offered a choice between the more expensi...
journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/00004424-199304000-00008
更新日期:1993-04-01 00:00:00
abstract:RATIONALE AND OBJECTIVES:The clinically most widely used devices (Porstmann-plug, Rashkind-umbrella, Botallooccluder) have inherent specific limitations (eg, transarterial approach, residual shunts, limited retrieval). The authors assess practicability, efficacy, and tissue reaction of the new retrievable transvenous p...
journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/00004424-199709000-00004
更新日期:1997-09-01 00:00:00
abstract:OBJECTIVES:The aim of this study was to achieve initial experience with non-contrast-enhanced (ne) magnetic resonance angiography (MRA) of the lower leg arteries in patients with peripheral arterial occlusive disease (PAOD) at 7 T. MATERIALS AND METHODS:Seven patients with PAOD were examined on a 7-T whole-body magnet...
journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/RLI.0000000000000044
更新日期:2014-05-01 00:00:00
abstract:RATIONALE AND OBJECTIVES:The authors evaluate the use of a new device for interventional creation of atrial septal defects (ASD) working with high-frequency alternating current in an in vitro study with porcine atria. METHODS:The device consists of a symmetrical cage of six superelastic monofile wires, including a mic...
journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/00004424-199702000-00003
更新日期:1997-02-01 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::Thirty patients [four normals, eight with mild and 18 with severe coronary artery disease (CAD)] were studied to evaluate left ventricular function type and post coronary angiography. The end diastolic volume (EDV), end systolic volume (ESV), ejection fraction (EF) and the regional contractility fractions (RCF) of eig...
journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/00004424-197603000-00009
更新日期:1976-03-01 00:00:00
abstract:RATIONALE AND OBJECTIVES:Iopromide is a new monomeric, nonionic contrast agent that exhibits low osmolality and low viscosity in high concentration in aqueous solutions. Double-blind, randomized clinical trials have established the efficacy, safety, and tolerance of iopromide for excretory urography, coronary angiograp...
journal_title:Investigative radiology
pub_type: 临床试验,杂志文章,随机对照试验
doi:10.1097/00004424-199405001-00015
更新日期:1994-05-01 00:00:00
abstract:RATIONALE AND OBJECTIVES:The purpose of this study evaluating a cesium iodide-amorphous silicon-based flat-panel detector was to optimize the x-ray spectrum for chest radiography combining excellent contrast-detail visibility with reduced patient exposure. MATERIALS AND METHODS:A Lucite plate with 36 drilled holes of ...
journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/01.rli.0000138091.96320.f8
更新日期:2004-10-01 00:00:00
abstract:RATIONALE AND OBJECTIVES:The capability of an indirect computed tomographic lymphography (CT-LG) using a nonionic monometric contrast medium iopamidol for visualizing breast lymphatic pathways was preliminarily tested. MATERIALS AND METHODS:In 10 female dogs, a total of 0.5 and 1 mL of undiluted iopamidol was injected...
journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/00004424-200302000-00002
更新日期:2003-02-01 00:00:00
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journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/RLI.0000000000000111
更新日期:2015-03-01 00:00:00
abstract:RATIONALE AND OBJECTIVES:To improve the accuracy of magnetic resonance imaging (MRI) in evaluating the response of osteosarcomas to preoperative chemotherapy, the authors developed a technique of mapping tumor necrosis and viability by quantitating slope values of gadolinium-DTPA (Gd-DTPA) uptake on dynamic fast low-an...
journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/00004424-199205000-00010
更新日期:1992-05-01 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::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::There are a number of sonographic findings seen in fibroadenoma of the breast. In a retrospective study, we examined the biopsy results of 59 masses given the sonographic diagnosis of fibroadenoma. We also reviewed the sonograms of an additional 26 biopsy-proven fibroadenomas that were not diagnosed as such with ultra...
journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/00004424-198601000-00006
更新日期:1986-01-01 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::An isotopic radiation source 125I was investigated for use in soft tissue radiaography, with particular attention to possible use in mammography for mass screening. Film sensitivities, exposure rates, absorbed doeses, contrast and resolution were determined, and compared to conventional x-ray units. It was found that ...
journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/00004424-197509000-00007
更新日期:1975-09-01 00:00:00
abstract:OBJECTIVES:The aim of this study was to explore the impact of dynamic contrast-enhanced (DCE) computer tomography (CT) as a biomarker in metastatic renal cell carcinoma (mRCC). MATERIALS AND METHODS:Twelve patients with favorable or intermediate Memorial Sloan Kettering Cancer Center risk group and clear cell mRCC par...
journal_title:Investigative radiology
pub_type: 杂志文章,随机对照试验
doi:10.1097/RLI.0000000000000058
更新日期:2014-09-01 00:00:00
abstract::Radiolabeled ioversol was injected intravenously into two male and two female beagle dogs (6.7 to 10.4 kg) at two dose levels each (0.2 and 1.0 g I/kg). Blood levels of radioactivity were monitored at 2, 5, 10, 20, 40, 60, 90, and 120 minutes and at one and two days. Urine and feces were collected in metabolism cages ...
journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/00004424-198906001-00005
更新日期:1989-06-01 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::Iohexol and meglumine-sodium diatrizoate were injected intravenously into 18 pigs as either a 99:1 or 1:99 mixture. Blood samples were taken for 30 minutes and the concentration of each of the two contrast media was measured by means of a double labeling technique with 125I and 131I. Relative concentrations of iohexol...
journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/00004424-198511000-00016
更新日期:1985-11-01 00:00:00
abstract:RATIONALE AND OBJECTIVES:To develop a new animal model for the evaluation of the renal tolerance of contrast agent and its application to diatrizoate and iotrolan injections in comparison to saline and mannitol solution. MATERIALS AND METHODS:The nephrotoxic potential of intravenously injected contrast agents in Beagl...
journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/01.rli.0000087096.61127.13
更新日期:2003-11-01 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::Low-dose transaxial tomography is a technique that can produce cross-sectional images of the hips and femurs in children to permit calculation of the angle of femoral anteversion. Transaxial tomography was compared with computed tomography in terms of measured radiation dose and image quality. Transaxial tomography wa...
journal_title:Investigative radiology
pub_type: 杂志文章
doi:
更新日期:1985-12-01 00:00:00
abstract:PURPOSE:We sought to evaluate the potential of dynamic contrast enhancement after the intravenous administration of an iodine-based contrast medium in full-field digital mammography. MATERIAL AND METHODS:A protocol for image acquisition was established for contrast-enhanced mammography and the mammography unit (Senogr...
journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/01.rli.0000167421.83203.4e
更新日期:2005-07-01 00:00:00
abstract:RATIONALE AND OBJECTIVES:The reflux of ethanol into the peritoneal cavity during percutaneous ethanol injection therapy (PEIT) of liver neoplasms may cause pain and other side effects. This article studies the optimal injection technique to minimize the reflux of ethanol. METHODS:A technique using normal postmortem pi...
journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/00004424-199211000-00008
更新日期:1992-11-01 00:00:00