Dow-Mu Koh

Institute of Cancer Research, Londinium, England, United Kingdom

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Publications (84)244.32 Total impact

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    ABSTRACT: This open-label phase I dose-escalation study investigated the safety, efficacy, pharmacokinetics (PK), and dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) effects of the oral angiokinase inhibitor nintedanib in patients with advanced solid tumors. Nintedanib was administered once daily continuously, starting at 100 mg and later amended to allow evaluation of 250 mg b.i.d. The primary endpoint was maximum tolerated dose (MTD). DCE-MRI studies were performed at baseline and on days 2 and 28. Fifty-one patients received nintedanib 100-450 mg once daily (n = 40) or 250 mg b.i.d. (n = 11). Asymptomatic reversible liver enzyme elevations (grade 3) were dose limiting in 2 of 5 patients at 450 mg once daily. At 250 mg b.i.d., 2 of 11 patients experienced dose-limiting toxicity (grade 3 liver enzyme elevation and gastrointestinal symptoms). Common toxicities included fatigue, diarrhea, nausea, vomiting, and abdominal pain (mainly grade ≤2). Among 45 patients, 22 (49%) achieved stable disease; 7 remained on treatment for >6 months. DCE-MRI of target lesions revealed effects in some patients at 200 and ≥400 mg once daily. Nintedanib is well tolerated by patients with advanced solid malignancies, with MTD defined as 250 mg b.i.d., and can induce changes in DCE-MRI. Disease stabilization >6 months was observed in 7 of 51 patients. ©AlphaMed Press; the data published online to support this summary is the property of the authors.
    The Oncologist 03/2015; DOI:10.1634/theoncologist.2014-0250 · 4.54 Impact Factor
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    ABSTRACT: Contrast-Enhanced Magnetic Resonance Lymphangiography (CE-MRL) presents some limitations: (i) it does not quantify lymphatic functionality; and (ii) enhancement of vascular structures may confound image interpretation. Furthermore, although CE-MRL is well described in the published literature for the lower limbs, there is a paucity of data with regards to its use in the upper limbs. In this proof-of-principle study, we propose a new protocol to perform CE-MRL in the upper limbs of patients with breast cancer-related lymphedema (BCRL) which addresses these limitations. CE-MRL was performed using a previously published (morphological) protocol and the proposed protocol (quantitative) on both the ipsilateral (abnormal) and contralateral (normal) arms of patients with BCRL. The quantitative protocol employs contrast agent (CA) intradermal injections at a lower concentration to prevent T2*-related signal decay. Both protocols provided high-resolution three-dimensional images of upper limb lymphatic vessels. CA uptake curves were utilized to distinguish between lymphatic vessels and vascular structures. The quantitative protocol minimized venous enhancement and avoided spurious delays in lymphatic enhancement due to short T2* values, enabling correct CA uptake characterization. The quantitative protocol was therefore employed to measure the lymphatic fluid velocity, which demonstrated functional differences between abnormal and normal arms. The velocity values were in agreement with previously reported lymphoscintigraphy and near infra-red lymphangiography measurements. This work demonstrated the feasibility of CE-MRL of the upper limbs in patients with BRCL, introducing an advanced imaging and analysis protocol suitable for anatomical and functional study of the lymphatic system.
    Lymphatic Research and Biology 03/2015; DOI:10.1089/lrb.2014.0039 · 1.66 Impact Factor
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    ABSTRACT: The objectives are to examine the reproducibility of functional MR imaging in children with solid tumours using quantitative parameters derived from diffusion-weighted (DW-) and dynamic contrast enhanced (DCE-) MRI. Patients under 16-years-of age with confirmed diagnosis of solid tumours (n = 17) underwent free-breathing DW-MRI and DCE-MRI on a 1.5 T system, repeated 24 hours later. DW-MRI (6 b-values, 0-1000 sec/mm(2)) enabled monoexponential apparent diffusion coefficient estimation using all (ADC0-1000) and only ≥100 sec/mm(2) (ADC100-1000) b-values. DCE-MRI was used to derive the transfer constant (K(trans)), the efflux constant (kep), the extracellular extravascular volume (ve), and the plasma fraction (vp), using a study cohort arterial input function (AIF) and the extended Tofts model. Initial area under the gadolinium enhancement curve and pre-contrast T1 were also calculated. Percentage coefficients of variation (CV) of all parameters were calculated. The most reproducible cohort parameters were ADC100-1000 (CV = 3.26 %), pre-contrast T1 (CV = 6.21 %), and K(trans) (CV = 15.23 %). The ADC100-1000 was more reproducible than ADC0-1000, especially extracranially (CV = 2.40 % vs. 2.78 %). The AIF (n = 9) derived from this paediatric population exhibited sharper and earlier first-pass and recirculation peaks compared with the literature's adult population average. Free-breathing functional imaging protocols including DW-MRI and DCE-MRI are well-tolerated in children aged 6 - 15 with good to moderate measurement reproducibility. • Diffusion MRI protocol is feasible and well-tolerated in a paediatric oncology population. • DCE-MRI for pharmacokinetic evaluation is feasible and well tolerated in a paediatric oncology population. • Paediatric arterial input function (AIF) shows systematic differences from the adult population-average AIF. • Variation of quantitative parameters from paired functional MRI measurements were within 20 %.
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    ABSTRACT: Angiogenesis is a key cancer hallmark involved in tumor growth and metastasis development. Angiogenesis and tumor microenvironment significantly influence the response of tumors to therapies. Imaging techniques have changed our understanding of the process of angiogenesis, the resulting vascular performance, and the tumor microenvironment. This article reviews the status and potential clinical value of the imaging modalities used to assess the status of tumor vasculature in vivo, before, during, and after treatment. Copyright © 2015 Mosby, Inc. All rights reserved.
    Current problems in diagnostic radiology 03/2015; DOI:10.1067/j.cpradiol.2015.02.009
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    ABSTRACT: Angiogenesis is a key cancer hallmark involved in tumor growth and metastasis development. Tumor angiogenesis is the process whereby new blood vessels are formed to supply nutrients and oxygen to support the growth of tumors. This article reviews the biological basis behind imaging features and the different imaging modalities used to assess the status of tumor neovasculature in vivo at different scales: structural, functional, and molecular. Copyright © 2015 Mosby, Inc. All rights reserved.
    Current problems in diagnostic radiology 03/2015; DOI:10.1067/j.cpradiol.2015.02.010
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    ABSTRACT: The aim of this study was to determine the value of SUV-based metabolic parameters derived from pretreatment F-FDG PET/CT of colorectal liver metastases in predicting disease response, progression-free survival (PFS), and overall survival (OS). We retrospectively reviewed 70 colorectal patients with liver metastases who underwent pretreatment F-FDG PET/CT. SUVmean, SUVmax, TLG (total lesion glycolysis), metabolic tumor volume, and metabolic tumor diameter were the metabolic parameters derived from volume of interest analysis of the most FDG-avid liver lesion in each subject. Clinical and laboratory parameters were recorded. Tumor response was assessed by response evaluation criteria in solid tumors 1.1 criteria at 12 weeks after treatment. Associations between tumor response, metabolic parameters, and clinical/laboratory parameters were examined by 1-way analysis of variance. The relationship of the metabolic parameters with PFS and OS was determined by Kaplan-Meier analyses and further confirmed with multivariate Cox regression analyses. SUVmean less than 4.48, SUVmax less than 6.59, TLG less than 75.2, metabolic tumor volume less than 4.49 cm, and hemoglobin level greater than or equal to 11 g/dL were associated with longer PFS (P < 0.05). Prior surgery or radiofrequency ablation to the liver metastases was the only additional factor shown to be associated with longer OS. SUV-based metabolic parameters derived from pretreatment F-FDG PET/CT can predict PFS in colorectal liver metastases.
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    ABSTRACT: Objective: The aim of this study was to prospectively evaluate the feasibility of monitoring treatment response to chemotherapy in patients with non-small cell lung carcinoma using functional diffusion maps (fDMs). Materials and Methods: This study was approved by the Cantonal Research Ethics Committee and informed written consent was obtained from all patients. Nine patients (mean age = 66 years; range = 53-76 years, 5 females, 4 males) with overall 13 lesions were included. Imaging was performed within two weeks before initiation of chemotherapy and at one, two, and six weeks after initiation of chemotherapy. Imaging included a respiratory-triggered diffusion-weighted sequence including three b-factors (100, 600, and 800 s/mm(2)). Treatment response was defined by change in tumor diameter on computed tomography (CT) after two cycles of chemotherapy. Changes in the apparent diffusion coefficient (ADC) on a perlesion basis and the percentages of voxel with significantly increased or decreased ADCs on fDMs were analyzed using repeated measures analysis of variance (ANOVA). Changes in tumor size were used as covariate to examine the ability of ADCs and fDM parameters to predict treatment response. Results: Repeated measures ANOVA revealed that the percentage of voxels with increased ADCs on fDMs (p = 0.002) as well as the mean ADC increase (p = 0.011) were significantly higher in good responders with a large reduction in tumor size on CT. Conclusion: Our results indicate that the percentage of voxels with significantly increased ADCs on fDMs seems to be a promising biomarker for early prediction of treatment response in patients with non-small cell lung carcinoma. Contrary to averaged values, this approach allows the spatial heterogeneity of treatment response to be resolved.
    PLoS ONE 10/2014; 9(10):e108052. DOI:10.1371/journal.pone.0108052 · 3.53 Impact Factor
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    ABSTRACT: Liver perfusion magnetic resonance (MR) imaging is currently being actively investigated as a functional imaging technique that provides physiologic information on the microcirculation and microenvironment of liver tumors and the underlying liver. It has gained importance in light of antiangiogenic therapy for hepatocellular carcinoma and colorectal liver metastases. This article explains the various model-free and model-based approaches for liver perfusion MR imaging and their relative clinical utility. Relevant published works are summarized for each approach so that the reader can understand their relative strengths and weaknesses, to make an informed choice when performing liver perfusion MR imaging studies.
    Magnetic Resonance Imaging Clinics of North America 08/2014; 22(3):417–432. DOI:10.1016/j.mric.2014.04.011 · 0.80 Impact Factor
  • Dow-Mu Koh
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    ABSTRACT: Summary In the study by Joo et al ( 1 ), perfusion-sensitive parameters derived from diffusion-weighted (DW) magnetic resonance (MR) imaging using intravoxel incoherent motion (IVIM) analysis were significantly decreased 4 hours after administration of a vascular disrupting agent (VDA) (CKD-516), in keeping with drug-induced vascular collapse. A larger decrease in the perfusion-sensitive IVIM parameters was correlated with smaller tumor size increase 7 days after treatment.
    Radiology 08/2014; 272(2):307-308. DOI:10.1148/radiol.14140714 · 6.21 Impact Factor
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    ABSTRACT: BACKGROUND: Dichloroacetate (DCA) has been found to have antitumour properties. METHODS: We investigated the cellular and metabolic responses to DCA treatment and recovery in human colorectal (HT29, HCT116 WT and HCT116 Bax-ko), prostate carcinoma cells (PC3) and HT29 xenografts by flow cytometry, western blotting, electron microscopy, (1)H and hyperpolarised (13)C-magnetic resonance spectroscopy. RESULTS: Increased expression of the autophagy markers LC3B II was observed following DCA treatment both in vitro and in vivo. We observed increased production of reactive oxygen species (ROS) and mTOR inhibition (decreased pS6 ribosomal protein and p4E-BP1 expression) as well as increased expression of MCT1 following DCA treatment. Steady-state lactate excretion and the apparent hyperpolarised [1-(13)C] pyruvate-to-lactate exchange rate (kPL) were decreased in DCA-treated cells, along with increased NAD(+)/NADH ratios and NAD(+). Steady-state lactate excretion and kPL returned to, or exceeded, control levels in cells recovered from DCA treatment, accompanied by increased NAD(+) and NADH. Reduced kPL with DCA treatment was found in HT29 tumour xenografts in vivo. CONCLUSIONS: DCA induces autophagy in cancer cells accompanied by ROS production and mTOR inhibition, reduced lactate excretion, reduced kPL and increased NAD(+)/NADH ratio. The observed cellular and metabolic changes recover on cessation of treatment.
    British Journal of Cancer 07/2014; 111(2). DOI:10.1038/bjc.2014.281 · 4.82 Impact Factor
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    ABSTRACT: Purpose To compare revised Choi criteria that incorporate concurrent size and attenuation changes at early follow-up imaging with Response Evaluation Criteria in Solid Tumors (RECIST) 1.1 and original Choi criteria in stratification of clinical outcomes in patients with metastatic renal cell carcinoma (mRCC) treated with sunitinib. Materials and Methods Institutional review board approved this retrospective study and waived informed consent. Baseline and first follow-up computed tomographic scans in 69 patients (50 men, 19 women; mean age, 60.3 years; range, 19-83 years) with mRCC treated with sunitinib from October 1, 2008, to March 1, 2013, were evaluated for tumor response by using RECIST 1.1, original Choi criteria, and revised Choi criteria. Correlations with overall survival (OS) and progression-free survival (PFS) were compared and stratified according to each radiologic criteria with Kaplan-Meier and multivariate Cox regression analysis. Results Median follow-up time was 29.7 months (95% confidence interval [CI]: 18.9, 45.9). Response according to revised Choi criteria was independently correlated with OS (hazard ratio, 0.47 [95% CI: 0.23, 0.99]; P = .046) and PFS (hazard ratio, 0.53 [95% CI: 0.29, 0.99]; P = .047). Response according to RECIST was not significantly correlated with OS (hazard ratio, 0.65 [95% CI: 0.27, 1.58]; P = .344) or PFS (hazard ratio, 0.89 [95% CI: 0.42, 1.91]; P = .768). Response according to original Choi criteria was not significantly correlated with OS (hazard ratio, 0.60 [95% CI: 0.32, 1.11]; P = .106) or PFS (hazard ratio, 0.59 [95% CI: 0.34, 1.02]; P = .060). Median OS and PFS in responders according to revised Choi criteria was 39.4 months (95% CI: 9.1, upper limit not estimated) and 13.7 months (95% CI: 6.4, 24.6), respectively, compared with 12.8 months (95% CI: 8.7, 18.0) and 5.3 months (95% CI: 3.9, 8.4), respectively, in nonresponders. Conclusion Contemporaneous reduction in tumor size and attenuation were correlated with favorable clinical outcomes. Response according to revised Choi criteria showed better correlation with clinical outcomes compared with that according to RECIST or original Choi criteria in patients with mRCC treated with sunitinib. © RSNA, 2014.
    Radiology 05/2014; DOI:10.1148/radiol.14132702 · 6.21 Impact Factor
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    ABSTRACT: We investigated how the technical differences between ss-EPI(R=2), FLASH(R=2) and FLASH(R=3) ACS acquisition methods visually manifest themselves in the context of WBDWI imaging. We analyzed: geometric distortion, SNR, overall image quality, and inter-station registration. FLASH(R=3) had the highest geometric fidelity, fewer image artifacts, and good station-station alignment. These advantages are offset by a lower SNR of ~17%: this may be partially responsible for the tendency of FLASH(R=2) ACS data to be rated higher than FLASH(R = 3) ACS data in terms of overall MIP quality. There was no situation in this study in which ss-EPI outperformed FLASH.
    Joint Annual Meeting ISMRM-ESMRMB, Milan, Italy; 05/2014
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    ABSTRACT: The intra-voxel incoherent motion (IVIM) model relates signal decay on diffusion-weighted MRI (DWI) to tissue characteristics of perfusion and diffusivity. We explored the effects of altering the diffusion time of DWI sequences on IVIM perfusion (f,D*) and diffusion (D) related parameters in abdominal organs of healthy volunteers. At longer diffusion times, the calculated perfusion fraction (f) was significantly increased while the effect on the D and D* parameters was more variable, depending on the organ under study. The diffusion time has a significant impact on measured IVIM parameters in abdominal organs and should be reported when employing the IVIM model.
    Joint Annual Meeting ISMRM-ESMRMB, Milan, Italy; 05/2014
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    ABSTRACT: Respiratory motion commonly confounds abdominal DWI, and motion minimisation strategies adversely affect scan efficiency and comfort. Blurring is due to post-acquisition combination of images from separate signal averages and diffusion-gradient directions, and is not inherent to the images. In a volunteer cohort where all images were stored separately, taking a (voxel-by-voxel) median image instead of a mean at each b-value yields parameter maps with much improved sharpness while still retaining tissue features. ADCs from ROIs in liver and kidneys were 108±18 vs 120±26 (p=0.007) and 182±17 vs 188±13 (p=0.04) x10-5 mm2s-1 for median and mean, respectively.
    Joint Annual Meeting ISMRM-ESMRMB, Milan, Italy; 05/2014
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    ABSTRACT: In this article, we review recent updates in the deployment of diffusion weighted magnetic resonance imaging (DW-MRI) in oncology for disease detection and characterization. We appraise the use of DW-MRI for the evaluation of treatment response, including its emerging role as a predictive and/or prognostic biomarker. We discuss the use of more sophisticated data analysis to derive quantitative parameters, particular those that account for non-mono-exponential signal attenuation behavior of DW-MRI in tissues. Last but not least, we survey the unfulfilled challenges and potential future applications of DW-MRI. Knowledge of the fundamentals of DW-MRI is assumed and will not be discussed.
    05/2014; 2(5). DOI:10.1007/s40134-014-0044-1
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    ABSTRACT: We describe our semi-automatic segmentation of whole-body diffusion-weighted MRI (WBDWI) using a Markov random field (MRF) model to derive tumor total diffusion volume (tDV) and associated global apparent diffusion coefficient (gADC); and demonstrate the feasibility of using these indices for assessing tumor burden and response to treatment in patients with bone metastases. WBDWI was performed on eleven patients diagnosed with bone metastases from breast and prostate cancers before and after anti-cancer therapies. Semi-automatic segmentation incorporating a MRF model was performed in all patients below the C4 vertebra by an experienced radiologist with over eight years of clinical experience in body DWI. Changes in tDV and gADC distributions were compared with overall response determined by all imaging, tumor markers and clinical findings at serial follow up. The segmentation technique was possible in all patients although erroneous volumes of interest were generated in one patient because of poor fat suppression in the pelvis, requiring manual correction. Responding patients showed a larger increase in gADC (median change = +0.18, range = −0.07 to +0.78×10−3 mm2/s) after treatment compared to non-responding patients (median change = −0.02, range = −0.10 to +0.05×10−3 mm2/s, p = 0.05, Mann-Whitney test), whereas non-responding patients showed a significantly larger increase in tDV (median change = +26%, range = +3 to +284%) compared to responding patients (median change = −50%, range = −85 to +27%, p = 0.02, Mann-Whitney test). Semi-automatic segmentation of WBDWI is feasible for metastatic bone disease in this pilot cohort of 11 patients, and could be used to quantify tumor total diffusion volume and median global ADC for assessing response to treatment.
    PLoS ONE 04/2014; 9(4):e91779. DOI:10.1371/journal.pone.0091779 · 3.53 Impact Factor
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    ABSTRACT: The early identification of children presenting ALKF1174L-mutated neuroblastoma, which are associated with resistance to the promising ALK inhibitor crizotinib and a marked poorer prognosis, has become a clinical priority. In comparing the radiology of the novel Th-ALKF1174L/Th-MYCN and the well-established Th-MYCN genetically-engineered murine models of neuroblastoma using MRI, we have identified a marked ALKF1174L-driven vascular phenotype. We demonstrate that quantitation of the transverse relaxation rate R2* (s-1) using intrinsic susceptibility-MRI under baseline conditions and during hyperoxia, can robustly discriminate this differential vascular phenotype, and identify MYCN-driven tumors harboring the ALKF1174L mutation with high specificity and selectivity. Intrinsic susceptibility-MRI could thus potentially provide a non-invasive and clinically-exploitable method to help identifying children with MYCN-driven neuroblastoma harboring the ALKF1174L mutation at the time of diagnosis.
    PLoS ONE 03/2014; 9(3):e92886. DOI:10.1371/journal.pone.0092886 · 3.53 Impact Factor
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    ABSTRACT: Autophagy is a highly regulated, energy dependent cellular process where proteins, organelles and cytoplasm are sequestered in autophagosomes and digested to sustain cellular homeostasis. We hypothesized that during autophagy induced in cancer cells by i) starvation through serum and amino acid deprivation or ii) treatment with PI-103, a class I PI3K/mTOR inhibitor, glycolytic metabolism would be affected, reducing flux to lactate, and that this effect may be reversible. We probed metabolism during autophagy in colorectal HT29 and HCT116 Bax knock-out cells using hyperpolarized 13C-magnetic resonance spectroscopy (MRS) and steady-state 1H-MRS. 24 hr PI103-treatment or starvation caused significant reduction in the apparent forward rate constant (kPL) for pyruvate to lactate exchange compared with controls in HT29 (100 μM PI-103: 82%, p = 0.05) and HCT116 Bax-ko cells (10 μM PI-103: 53%, p = 0.05; 20 μM PI-103: 42%, p<0.0001; starvation: 52%, p<0.001), associated with reduced lactate excretion and intracellular lactate in all cases, and unchanged lactate dehydrogenase (LDH) activity and increased NAD+/NADH ratio following PI103 treatment or decreased LDH activity and unchanged NAD+/NADH ratio following starvation. After 48 hr recovery from PI103 treatment, kPL remained below control levels in HT29 cells (74%, p = 0.02), and increased above treated values, but remained below 24 hr vehicle-treated control levels in HCT116 Bax-ko cells (65%, p = 0.004) both were accompanied by sustained reduction in lactate excretion, recovery of NAD+/NADH ratio and intracellular lactate. Following recovery from starvation, kPL was significantly higher than 24 hr vehicle-treated controls (140%, p = 0.05), associated with increased LDH activity and total cellular NAD(H). Changes in kPL and cellular and excreted lactate provided measureable indicators of the major metabolic processes accompanying starvation- and drug-induced autophagy. The changes are reversible, returning towards and exceeding control values on cellular recovery, which potentially identifies resistance. kPL (hyperpolarized 13C-MRS) and lactate (1H-MRS) provide useful biomarkers for the autophagic process, enabling non-invasive monitoring of the Warburg effect.
    PLoS ONE 03/2014; 9(3):e92645. DOI:10.1371/journal.pone.0092645 · 3.53 Impact Factor
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    ABSTRACT: PURPOSE: To evaluate the effect on diffusion-weighted image-derived parameters in the apparent diffusion coefficient (ADC) and intra-voxel incoherent motion (IVIM) models from choice of either free-breathing or navigator-controlled acquisition. MATERIALS AND METHODS: Imaging was performed with consent from healthy volunteers (n = 10) on a 1.5T Siemens Avanto scanner. Parameter-matched free-breathing and navigator-controlled diffusion-weighted images were acquired, without averaging in the console, for a total scan time of ∼10 minutes. Regions of interest were drawn for renal cortex, renal pyramid, whole kidney, liver, spleen, and paraspinal muscle. An ADC diffusion model for these regions was fitted for b-values ≥ 250 s/mm(2) , using a Levenberg-Marquardt algorithm, and an IVIM model was fitted for all images using a Bayesian method. RESULTS: ADC and IVIM parameters from the two acquisition regimes show no significant differences for the cohort; individual cases show occasional discrepancies, with outliers in parameter estimates arising more commonly from navigator-controlled scans. The navigator-controlled acquisitions showed, on average, a smaller range of movement for the kidneys (6.0 ± 1.4 vs. 10.0 ± 1.7 mm, P = 0.03), but also a smaller number of averages collected (3.9 ± 0.1 vs. 5.5 ± 0.2, P < 0.01) in the allocated time. CONCLUSION: Navigator triggering offers no advantage in fitted diffusion parameters, whereas free-breathing appears to offer greater confidence in fitted diffusion parameters, with fewer outliers, for matched acquisition periods.J. Magn. Reson. Imaging 2013. © 2013 Wiley Periodicals, Inc.
    Journal of Magnetic Resonance Imaging 01/2014; 39(1). DOI:10.1002/jmri.24140 · 2.79 Impact Factor
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    ABSTRACT: In addition to the diffusion coefficient, fitting the intravoxel incoherent motion model to multiple b-value diffusion-weighted MR data gives pseudo-diffusion measures associated with rapid signal attenuation at low b-values that are of use in the assessment of a number of pathologies. When summary measures are required, such as the average parameter for a region of interest, least-squares based methods give adequate estimation accuracy. However, using least-squares methods for pixel-wise fitting typically gives noisy estimates, especially for the pseudo-diffusion parameters, which limits the applicability of the approach for assessing spatial features and heterogeneity. In this article, a Bayesian approach using a shrinkage prior model is proposed and is shown to substantially reduce estimation uncertainty so that spatial features in the parameters maps are more clearly apparent. The Bayesian approach has no user-defined parameters, so measures of parameter variation (heterogeneity) over regions of interest are determined by the data alone, whereas it is shown that for the least-squares estimates, measures of variation are essentially determined by user-defined constraints on the parameters. Use of a Bayesian shrinkage prior approach is, therefore, recommended for intravoxel incoherent motion modeling. Magn Reson Med, 2013. © 2013 Wiley Periodicals, Inc.
    Magnetic Resonance in Medicine 01/2014; 71(1). DOI:10.1002/mrm.24649 · 3.40 Impact Factor

Publication Stats

2k Citations
244.32 Total Impact Points

Institutions

  • 2004–2014
    • Institute of Cancer Research
      • CR-UK and EPSRC Cancer Imaging Centre
      Londinium, England, United Kingdom
  • 2003–2014
    • The Royal Marsden NHS Foundation Trust
      Londinium, England, United Kingdom
  • 2011
    • Ontario Institute for Cancer Research
      Toronto, Ontario, Canada
  • 2009
    • University of Michigan
      Ann Arbor, Michigan, United States
    • Johns Hopkins Medicine
      • Department of Radiology and Radiological Science
      Baltimore, MD, United States
    • NYU Langone Medical Center
      • Department of Radiology
      New York City, NY, United States