Abstract:
:The aim of this study was to evaluate the change of breast density in the normal breast of patients receiving neoadjuvant chemotherapy (NAC). Forty-four breast cancer patients were studied. MRI acquisition was performed before treatment (baseline), and 4 and 12 weeks after treatment. A computer-algorithm-based program was used to segment breast tissue and calculate breast volume (BV), fibroglandular tissue volume (FV), and percent density (PD) (the ratio of FV over BV × 100%). The reduction of FV and PD after treatment was compared with baseline using paired t-tests with a Bonferroni-Holm correction. The association of density reduction with age was analyzed. FV and PD after NAC showed significant decreases compared with the baseline. FV was 110.0 ml (67.2, 189.8) (geometric mean (interquartile range)) at baseline, 104.3 ml (66.6, 164.4) after 4 weeks (p < 0.0001), and 94.7 ml (60.2, 144.4) after 12 weeks (comparison with baseline, p < 0.0001; comparison with 4 weeks, p = 0.016). PD was 11.2% (6.4, 22.4) at baseline, 10.6% (6.6, 20.3) after 4 weeks (p < 0.0001), and 9.7% (6.2, 17.9) after 12 weeks (comparison with baseline, p = 0.0001; comparison with 4 weeks, p = 0.018). Younger patients tended to show a higher density reduction, but overall correlation with age was only moderate (r = 0.28 for FV, p = 0.07, and r = 0.52 for PD, p = 0.0003). Our study showed that breast density measured from MR images acquired at 3T MR can be accurately quantified using a robust computer-aided algorithm based on non-parametric non-uniformity normalization (N3) and an adaptive fuzzy C-means algorithm. Similar to doxorubicin and cyclophosphamide regimens, the taxane-based NAC regimen also caused density atrophy in the normal breast and showed reduction in FV and PD. The effect of breast density reduction was age related and duration related.
journal_name
NMR Biomedjournal_title
NMR in biomedicineauthors
Chen JH,Pan WF,Kao J,Lu J,Chen LK,Kuo CC,Chang CK,Chen WP,McLaren CE,Bahri S,Mehta RS,Su MYdoi
10.1002/nbm.3006subject
Has Abstractpub_date
2013-12-01 00:00:00pages
1705-13issue
12eissn
0952-3480issn
1099-1492journal_volume
26pub_type
杂志文章abstract::The aim of this study was to investigate the diffusion time dependence of signal-versus-b curves obtained from diffusion-weighted magnetic resonance imaging (DW-MRI) of sub-acute ischaemic lesions in stroke patients. In this case series study, 16 patients with sub-acute ischaemic stroke were examined with DW-MRI using...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.1376
更新日期:2009-07-01 00:00:00
abstract::During magnetic resonance imaging (MRI) examinations, the average specific absorption rate (SAR) of the whole body is calculated as an index of global energy deposition in biological tissue without taking into account the presence of metallic implants or conductive materials. However, this global SAR calculation is no...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.3849
更新日期:2018-01-01 00:00:00
abstract::Diffusion measurements were performed on the N-acetyl aspartate (NAA) signal in in situ brains (in vivo and post-mortem) and on in vitro brain tissue at 37 degrees C using wide ranges of b-values (from 0 up to 4.5 x 10(6) s/cm2 and 35.8 x 10(6) s/cm2 for the in vivo and the in vitro cases, respectively). In vivo and i...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/(sici)1099-1492(199804)11:2<67::aid-nbm503
更新日期:1998-04-01 00:00:00
abstract::The availability of high-field-strength magnetic resonance imaging (MRI) systems has brought about the development of techniques that aim to map myelination via the exploitation of various contrast mechanisms. Myelin mapping techniques have the potential to provide tools for the diagnosis and treatment of diseases, su...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.3877
更新日期:2018-03-01 00:00:00
abstract::By combining intravoxel incoherent motion (IVIM) and diffusion tensor imaging (DTI) we introduce a new diffusion model called intravoxel oriented flow (IVOF) that accounts for anisotropy of diffusion and the flow-related signal. An IVOF model using a simplified apparent flow fraction tensor (IVOFf ) is applied to diff...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.3584
更新日期:2016-10-01 00:00:00
abstract::Dynamic contrast-enhanced (DCE) magnetic resonance imaging (MRI) and proton (1H) magnetic resonance spectroscopy (MRS) provide structural and biochemical information, including vascular volume, vascular permeability and tissue metabolism. In this study, we performed analysis of the enhancement characteristic from DCE-...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.1511
更新日期:2010-10-01 00:00:00
abstract::The detection of Parkinson's disease (PD) in its preclinical stages prior to outright neurodegeneration is essential to the development of neuroprotective therapies and could reduce the number of misdiagnosed patients. However, early diagnosis is currently hampered by lack of reliable biomarkers. (1) H magnetic resona...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.2817
更新日期:2013-01-01 00:00:00
abstract::Balanced steady-state free precession imaging has recently been suggested for chemical exchange detection (bSSFPX). The objective of this work is to investigate the contributions of microstructural, chemical shift and chemical exchange effects to the asymmetry of the bSSFP profile at field strengths of 3 T and 9.4 T. ...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.4200
更新日期:2020-03-01 00:00:00
abstract::The present work aims to show the applicability of an analytical model for the optimisation of the STEAM sequence timing parameters for lactate detection at ultra high-field. The effects of the chemical shift displacement artefact on the J-modulated signal for a weakly-coupled spin system were considered in the three ...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.4440
更新日期:2020-11-02 00:00:00
abstract::A number of NMR spectroscopic and microscopic MRI (microMRI) techniques were used to study proton dynamics in canine tendon and articular cartilage immersed in normal saline solution (NaCl solution) and high-concentration phosphate-buffered saline (PBS) solution. In a proton CPMG experiment on tendons, the T(2) relaxa...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.1294
更新日期:2009-02-01 00:00:00
abstract::Quantitative analysis of extracts from two Ehrlich ascites tumour cell lines (Lettre cells) by 19F NMR in vitro demonstrated that one Lettre cell line (designated LLM) metabolized 30-50% less 5-fluorouracil to 5-fluoronucleotides when compared to the other cell line (designated LHM). HPLC analysis of these cellular ex...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.1940040605
更新日期:1991-12-01 00:00:00
abstract:INTRODUCTION:Sarcoidosis is a systemic granulomatous disease affecting in particular the respiratory tract. Cardiac magnetic resonance (CMR), including a measurement of T1 relaxation time, could potentially detect early stadia of sarcoidosis of the heart. The study aims to assess T1 mapping in the detection of early ca...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.4388
更新日期:2020-11-01 00:00:00
abstract::Management of brain tumours in children would benefit from improved non-invasive diagnosis, characterisation and prognostic biomarkers. Metabolite profiles derived from in-vivo MRS have been shown to provide such information. Studies indicate that using optimum a priori information on metabolite contents in the constr...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.1432
更新日期:2010-01-01 00:00:00
abstract::In order to investigate intervertebral disc (IVD) degeneration and repair, a quantitative non-invasive tool is needed. Various MRI methods including qCPMG, which yields dipolar echo relaxation time (T(DE)), magnetization transfer contrast (MTC), and (1)H and (2)H double quantum filtered (DQF) MRI were used in the pres...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.1493
更新日期:2010-07-01 00:00:00
abstract::Reconstruction of MRI data is based on exact knowledge of all magnetic field dynamics, since the interplay of RF and gradient pulses generates the signal, defines the contrast and forms the basis of resolution in spatial and spectral dimensions. Deviations caused by various sources, such as system imperfections, delay...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.3359
更新日期:2016-09-01 00:00:00
abstract::Several obstacles usually confound a straightforward perfusion analysis using dynamic-susceptibility contrast-based magnetic resonance imaging (DSC-MRI). In this work, it became possible to eliminate some of these sources of error by combining a multiple gradient-echo technique with parallel imaging (PI): first, the l...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.1107
更新日期:2007-06-01 00:00:00
abstract::Quantitative susceptibility mapping (QSM) is a recently developed MRI technique that provides a quantitative measure of tissue magnetic susceptibility. To compute tissue magnetic susceptibilities based on gradient echoes, QSM requires reliable unwrapping of the measured phase images and removal of contributions caused...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.3056
更新日期:2014-02-01 00:00:00
abstract::An indirect method for in vivo T2 mapping of 13 C-labeled metabolites using T2 and T2 * information of water protons obtained a priori is proposed. The T2 values of 13 C metabolites are inferred using the relationship to T2 ' of coexisting 1 H and the T2 * of 13 C metabolites, which is measured using routine hyperpola...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.3690
更新日期:2017-05-01 00:00:00
abstract::1H NMR spin-echo spectroscopy has been used to study the metabolism of exogenous compounds in human erythrocytes. The non-invasive nature of the technique and the continuous monitoring makes it ideal to investigate both the conversion of substrates and the occurrence and the nature of the products. Hydrolysis rates ma...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.1940030603
更新日期:1990-12-01 00:00:00
abstract::Acute kidney injury (AKI) in mice caused by sustained ischemia followed by reperfusion is associated with acute tubular necrosis and renal dysfunctional blood flow. Although the principal role of the kidney is the maintenance of acid-base balance, current imaging approaches are unable to assess this important paramete...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.3720
更新日期:2017-07-01 00:00:00
abstract::Glucosamine (GlcN) modulates fluoropyrimidine metabolism and enhances cytotoxicity of 5-fluorouridine (FUrd), but not of 5-fluorouracil (FUra), in human tumor models. To elucidate the underlying metabolic differences between FUra and FUrd, by the use of 19F and 31P NMR spectroscopy we studied these drugs in multicell ...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/(sici)1099-1492(199905)12:3<157::aid-nbm55
更新日期:1999-05-01 00:00:00
abstract::The purpose of this work was to carry out diffusion tensor imaging (DTI) at multiple diffusion times Td in skeletal muscle in normal subjects and chronic exertional compartment syndrome (CECS) patients and analyze the data with the random permeable barrier model (RPBM) for biophysical specificity. Using an institution...
journal_title:NMR in biomedicine
pub_type: 临床试验,杂志文章
doi:10.1002/nbm.3087
更新日期:2014-05-01 00:00:00
abstract::A noise figure and noise parameter measurement system was developed that consists of a combination spectrum and network analyzer, preamplifier, programmable power supply, noise source, tuning board, and desktop computer. The system uses the Y-factor method for noise figure calculation and allows calibrations to correc...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.3138
更新日期:2014-08-01 00:00:00
abstract::Previous studies have demonstrated that using hyperpolarized [2-13 C]pyruvate as a contrast agent can reveal 13 C signals from metabolites associated with the tricarboxylic acid (TCA) cycle. However, the metabolites detectable from TCA cycle-mediated oxidation of [2-13 C]pyruvate are the result of several metabolic st...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.3845
更新日期:2018-01-01 00:00:00
abstract::Traditional methods of measuring magnetization in magnetic fluid samples, such as vibrating sample magnetometry (VSM), are typically limited to maximum field strengths of about 1 T. This work demonstrates the ability of MRI to measure the magnetization associated with two commercial MRI contrast agents at 3 T by compa...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.1412
更新日期:2009-10-01 00:00:00
abstract::γ-Aminobutyric acid (GABA) and glutamate (Glu), major neurotransmitters in the brain, are recycled through glutamine (Gln). All three metabolites can be measured by magnetic resonance spectroscopy in vivo, although GABA measurement at 3 T requires an extra editing acquisition, such as Mescher-Garwood point-resolved sp...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.3847
更新日期:2018-01-01 00:00:00
abstract::A method to extract shapes of bubble polyhedra from three-dimensional nuclear magnetic resonance image data of foam has been developed. The method consists of four steps: first, to compute series of maximum intensity projection images from the three-dimensional NMR image data of foam to visualize the network structure...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/(sici)1099-1492(199701)10:1<13::aid-nbm443
更新日期:1997-01-01 00:00:00
abstract::The possibility of quantifying the superimposed signal of glutamate and glutamine (Glx) and its components by ¹H magnetic resonance spectroscopy (MRS) in the spinal cord is an exciting challenge with important clinical applications in neurological conditions. The spinal cord is a particularly difficult region of inter...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.2867
更新日期:2013-03-01 00:00:00
abstract::Lung cancer is a primary cause of cancer deaths worldwide. Timely detection of this pathology is necessary to delay or interrupt lung cancer progression, ultimately resulting in a possible better prognosis for the patient. In this context, magnetic resonance imaging (MRI) is especially promising. Ultra-short echo time...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.3790
更新日期:2017-11-01 00:00:00
abstract::The use of cerebral water as an internal intensity standard for the quantitation of spatially localized proton spectra of the human brain is investigated. The method is validated on standard samples of N-acetyl aspartate (NAA) and lactate, and possible sources of error are discussed. Using the STEAM pulse sequence, co...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.1940060114
更新日期:1993-01-01 00:00:00