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 stents. A second goal was to develop an engineering model for predicting radial forces generated by z stents. METHODS:Z stents were fashioned by hand using stainless steel wire and solder that connected the ends. The radial force was measured as a function of wire gauge, vessel diameter, leg length, and number of bends and compared with the theoretical values of radial force calculated by combining Castigliano's theorem and the law of Laplace. RESULTS:Theoretically predicted radial forces were within 8% of each observed value of radial force up to 70% spring compression. CONCLUSIONS:These results suggest that the z-stent model can be used to build custom stents with preselected values of radial force for clinical use. In addition, they can be used to design model investigational stents made of similar materials and surface areas to test the effects of radial force on biological response.
journal_name
Invest Radioljournal_title
Investigative radiologyauthors
Snowhill PB,Nosher JL,Siegel RL,Silver FHdoi
10.1097/00004424-200109000-00004keywords:
subject
Has Abstractpub_date
2001-09-01 00:00:00pages
521-30issue
9eissn
0020-9996issn
1536-0210journal_volume
36pub_type
杂志文章abstract:OBJECTIVES:The objective of this study was to evaluate the use of dielectric pads for improving high spatial resolution imaging of the inner ear at 7 T. MATERIALS AND METHODS:Two sets of dielectric pads were designed using electromagnetic simulations and implemented using a deuterated suspension of barium titanate. Th...
journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/RLI.0000000000000026
更新日期:2014-05-01 00:00:00
abstract::The rates at which the paramagnetic compounds deoxyhemoglobin (Hb) and methemoglobin (MHb) form in vivo within an area of hemorrhage are unknown. The present experiment establishes the baseline concentrations and rates of change in paramagnetic hemoglobin concentrations, as well as the pH in normal heparinized and clo...
journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/00004424-199003000-00006
更新日期:1990-03-01 00:00:00
abstract:OBJECTIVES:The aim of this study was to investigate the impact of a novel iterative denoising and image enhancement technique in T1-weighted precontrast and postcontrast volume-interpolated breath-hold examination (VIBE) of the abdomen on image quality, noise levels, and diagnostic confidence without change of acquisit...
journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/RLI.0000000000000746
更新日期:2020-11-18 00:00:00
abstract:RATIONALE AND OBJECTIVES:To assess the influence of injection rates and volumes on the arrival time of contrast material (CM) in the common carotid artery, the jugular vein and the resulting arterial-venous transit time. Additionally the relationship between injection parameters and the extent of a CM plateau was evalu...
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.0000105040.40925.c8
更新日期:2004-02-01 00:00:00
abstract:PURPOSE:The aim of this study was to evaluate the diagnostic performance of virtual noncalcium (VNCa) dual-energy computed tomography (DECT) reconstructions enabling visualization of bone marrow edema for characterization of incidental thoracolumbar compression fractures in routine thoracoabdominal staging computed tom...
journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/RLI.0000000000000458
更新日期:2018-07-01 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::The magnitude and time course of contrast enhancement in spontaneous canine brain tumors was determined for two contrast agents: meglumine iothalamate and sodium meglumine ioxaglate. Tumor enhancement during contrast infusion and at 5, 10, 15, 30 and 45 minutes was measured using quantitative computed tomography. Bloo...
journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/00004424-198411001-00007
更新日期:1984-11-01 00:00:00
abstract:OBJECTIVES:Imaging of the kidney using blood oxygen level dependent MR presents a major opportunity to examine differences in tissue oxygenation within the cortex and medulla applicable to human disease. We sought to define the differences between regions within kidneys and to optimize selection of regions of interest ...
journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/RLI.0b013e3181b4c1e8
更新日期:2009-09-01 00:00:00
abstract:RATIONALE AND OBJECTIVES:This study was conducted to determine whether significant reduction in radiation dose (250 mAs-->50 mAs), in chest computed tomography (CT) using volume acquisition affects image quality or the detectability of pathologic findings in the lung and mediastinum. METHODS:Phantom studies were condu...
journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/00004424-199802000-00002
更新日期:1998-02-01 00:00:00
abstract:OBJECTIVE:There is little published information regarding the efficacy of paclitaxel-coated balloon catheters except for the iopromide-containing formulation, and less is known about the kind of toxicity at overdose. The aim of our study was to assess 2 different paclitaxel matrix formulations on angioplasty balloon ca...
journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/RLI.0b013e31820577df
更新日期:2011-04-01 00:00:00
abstract:PURPOSE:The aim of this study was to develop a method to delineate the lethally frozen-tissue region (temperature less than -40°C) arising from interventional cryoablation procedures using a short tau inversion-recovery ultrashort echo-time (STIR-UTE) magnetic resonance (MR) imaging sequence. This method could serve as...
journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/RLI.0000000000000642
更新日期:2020-05-01 00:00:00
abstract:RATIONALE AND OBJECTIVES:The aim of the study was to examine the effects of azelastine on proliferation, clonogenic activity, cell-cycle, and migration of human aortic smooth-muscle cells (haSMCs) in vitro. METHODS:HaSMCs were treated for 4 days with azelastine (1 micromol/L, 25 micromol/L, 50 micromol/L). Half of the...
journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/00004424-200205000-00002
更新日期:2002-05-01 00:00:00
abstract::Because of the strong scientific evidence in support of radiation hormesis, we can no longer ignore this concept. There is, however, need for additional, carefully documented investigations in selected biological systems exposed to LLIR if the matter of radiation hormesis is to be settled once and for all. This need s...
journal_title:Investigative radiology
pub_type: 杂志文章,评审
doi:
更新日期:1993-05-01 00:00:00
abstract:RATIONALE AND OBJECTIVES:This study sought to evaluate prospectively the diagnostic potential of unenhanced and enhanced color Doppler and power Doppler for the differentiation of tumors and tumorlike lesions of the breast. METHODS:Ninety-two patients with 110 tumors or tumorlike lesions of the breast were investigate...
journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/00004424-199902000-00003
更新日期:1999-02-01 00:00:00
abstract:OBJECTIVE:To evaluate the degree of ischemic changes of the small intestine after arterial embolization of proximal or distal arteries with Gelfoam particles and coils in dogs. METHODS:Superselective arterial embolization in 18 dogs was performed using a coaxial catheter system. Gelfoam occlusion of the proximal level...
journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/00004424-199910000-00004
更新日期:1999-10-01 00:00:00
abstract::Three methods are presented which provide statistically acceptable estimates of mean transit time of opacified blood during angiography. While the methods vary in precision, the selection of the method appropriate for any particular experimental model depends on the degree of precision required to demonstrate the effe...
journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/00004424-197707000-00004
更新日期:1977-07-01 00:00:00
abstract:OBJECTIVES:The aim of this study was to develop and verify a method to obtain good temporal resolution T2-weighted 4-dimensional (4D-T2w) magnetic resonance imaging (MRI) by using motion information from T1-weighted 4D (4D-T1w) MRI, to support treatment planning in MR-guided radiotherapy. MATERIALS AND METHODS:Ten pat...
journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/RLI.0000000000000381
更新日期:2017-10-01 00:00:00
abstract::The effects of an intravenously administered nitroxyl spin label (PCA) on the magnetic resonance imaging (MRI) appearance and relaxation times of acute canine myocardial infarctions were studied. Twenty-four hours after ligation of the left anterior descending coronary artery (LAD), animals were either sacrificed imme...
journal_title:Investigative radiology
pub_type: 杂志文章
doi:
更新日期:1985-09-01 00:00:00
abstract:OBJECTIVES:: To evaluate the performance of a gadolinium-based contrast compound (P846) as well as an ultra-small particle of iron oxide agent (P904) in contrast-enhanced magnetic resonance angiography (MRA) in rabbits and to compare those agents with gadoterate meglumine (Gd-DOTA) for first pass and steady state imagi...
journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/RLI.0b013e31821ae21f
更新日期:2011-08-01 00:00:00
abstract:OBJECTIVE:To quantify independent pharmacokinetic parameters for differentiation of prostate pathology. MATERIAL AND METHODS:Twenty-seven patients with biopsy-proven prostate cancer (PSA: 1.4-16.1 ng/mL) underwent magnetic resonance imaging with a new dynamic contrast-enhanced, inversion-prepared dual-contrast gradien...
journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/RLI.0b013e31816b2f63
更新日期:2008-07-01 00:00:00
abstract::A new nonionic contrast medium (CM), ioxilan, was compared with iohexol and iopamidol. Following incubation of whole heparinized blood with CM, the morphology and osmotic fragility of erythrocytes were studied, the former by transmission electron microscopy. Effects on platelets and hemocoagulation were determined by ...
journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/00004424-198809001-00032
更新日期:1988-09-01 00:00:00
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 an...
journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/RLI.0b013e318188601f
更新日期:2008-11-01 00:00:00
abstract:RATIONALE AND OBJECTIVES:The authors compare the magnetic resonance (MR) phase contrast flow velocity measurements in varying concentric stenoses with invasive measurements obtained with a Doppler guidewire. METHODS:Flow velocity measurements were obtained using a calibrated 0.018 inch 12 MHz Doppler guidewire and a 1...
journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/00004424-199808000-00001
更新日期:1998-08-01 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::Thoracic metastases from squamous carcinoma and adenocarcinoma of the cervix were studied by reviewing 245 consecutive cases to describe comparative incidence, natural history, and radiographic patterns. The incidence of chest metastases was higher for adenocarcinoma (20%) than for squamous carcinoma (4%). Few patient...
journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/00004424-198003000-00004
更新日期:1980-03-01 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
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: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:RATIONALE AND OBJECTIVES:Low-field magnetic resonance imaging (MRI) evaluation of breast implants is described, with emphasis on the capabilities provided by different imaging sequences. METHODS:Open architecture MR images using a .064-T permanent magnet and three-dimensional Fourier transform and inversion recovery s...
journal_title:Investigative radiology
pub_type: 杂志文章
doi:10.1097/00004424-199408000-00009
更新日期:1994-08-01 00:00:00
abstract::A prospective, randomized study of the potential protective effects of corticosteroids administered as pretreatment against contrast material (CM) reactions is reported. Patients (n = 6,763) from multiple institutions received either a single dose of steroids (32 mg of oral methylprednisolone, approximately 2 hours be...
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:10.1097/00004424-198809001-00035
更新日期:1988-09-01 00:00:00