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  • 1
    Online Resource
    Online Resource
    Effect of Applying Leakage Correction on rCBV Measurement Derived From DSC-MRI in Enhancing and Nonenhancing Glioma
    Frontiers Media SA ; 2021
    In:  Frontiers in Oncology Vol. 11 ( 2021-3-23)
    Details
    In: Frontiers in Oncology, Frontiers Media SA, Vol. 11 ( 2021-3-23)
    Abstract: Relative cerebral blood volume (rCBV) is the most widely used parameter derived from DSC perfusion MR imaging for predicting brain tumor aggressiveness. However, accurate rCBV estimation is challenging in enhancing glioma, because of contrast agent extravasation through a disrupted blood-brain barrier (BBB), and even for nonenhancing glioma with an intact BBB, due to an elevated steady-state contrast agent concentration in the vasculature after first passage. In this study a thorough investigation of the effects of two different leakage correction algorithms on rCBV estimation for enhancing and nonenhancing tumors was conducted. Methods Two datasets were used retrospectively in this study: 1. A publicly available TCIA dataset (49 patients with 35 enhancing and 14 nonenhancing glioma); 2. A dataset acquired clinically at Erasmus MC (EMC, Rotterdam, NL) (47 patients with 20 enhancing and 27 nonenhancing glial brain lesions). The leakage correction algorithms investigated in this study were: a unidirectional model-based algorithm with flux of contrast agent from the intra- to the extravascular extracellular space (EES); and a bidirectional model-based algorithm additionally including flow from EES to the intravascular space. Results In enhancing glioma, the estimated average contrast-enhanced tumor rCBV significantly (Bonferroni corrected Wilcoxon Signed Rank Test, p & lt; 0.05) decreased across the patients when applying unidirectional and bidirectional correction: 4.00 ± 2.11 (uncorrected), 3.19 ± 1.65 (unidirectional), and 2.91 ± 1.55 (bidirectional) in TCIA dataset and 2.51 ± 1.3 (uncorrected), 1.72 ± 0.84 (unidirectional), and 1.59 ± 0.9 (bidirectional) in EMC dataset. In nonenhancing glioma, a significant but smaller difference in observed rCBV was found after application of both correction methods used in this study: 1.42 ± 0.60 (uncorrected), 1.28 ± 0.46 (unidirectional), and 1.24 ± 0.37 (bidirectional) in TCIA dataset and 0.91 ± 0.49 (uncorrected), 0.77 ± 0.37 (unidirectional), and 0.67 ± 0.34 (bidirectional) in EMC dataset. Conclusion Both leakage correction algorithms were found to change rCBV estimation with BBB disruption in enhancing glioma, and to a lesser degree in nonenhancing glioma. Stronger effects were found for bidirectional leakage correction than for unidirectional leakage correction.
    Type of Medium: Online Resource
    ISSN: 2234-943X
    URL: Article
    DOI: 10.3389/fonc.2021.648528
    Language: Unknown
    Publisher: Frontiers Media SA
    Publication Date: 2021
    detail.hit.zdb_id: 2649216-7
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  • 2
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    Online Resource
    Correction to: 3D APT and NOE CEST-MRI of healthy volunteers and patients with non-enhancing glioma at 3 T
    Springer Science and Business Media LLC ; 2022
    In:  Magnetic Resonance Materials in Physics, Biology and Medicine Vol. 35, No. 1 ( 2022-02), p. 75-75
    Details
    In: Magnetic Resonance Materials in Physics, Biology and Medicine, Springer Science and Business Media LLC, Vol. 35, No. 1 ( 2022-02), p. 75-75
    Type of Medium: Online Resource
    ISSN: 0968-5243 , 1352-8661
    URL: Article
    DOI: 10.1007/s10334-022-01002-w
    Language: English
    Publisher: Springer Science and Business Media LLC
    Publication Date: 2022
    detail.hit.zdb_id: 1502491-X
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  • 3
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    Online Resource
    Streamlined quantitative BOLD for detecting visual stimulus-induced changes in oxygen extraction fraction in healthy participants: toward clinical application in human glioma
    Springer Science and Business Media LLC ; 2023
    In:  Magnetic Resonance Materials in Physics, Biology and Medicine
    Details
    In: Magnetic Resonance Materials in Physics, Biology and Medicine, Springer Science and Business Media LLC
    Abstract: Monitoring brain oxygenation is critical in brain tumors, as low oxygenation influences tumor growth, pathological angiogenesis, and treatment resistance. This study examined the ability of the streamlined quantitative (sq)BOLD MRI technique to detect oxygenation changes in healthy individuals, as well as its potential application in a clinical setting. Methods We used the asymmetric spin echo (ASE) technique with FLAIR preparation, along with model-based Bayesian inference to quantify the reversible transverse relaxation rate ( R 2 ' ) and oxygen extraction fraction (OEF) across the brain at baseline and during visual stimulation in eight healthy participants at 3T; and two patients with glioma at rest only. Results Comparing sqBOLD-derived parameters between baseline and visual stimulation revealed a decrease in OEF from 0.56 ± 0.09 at baseline to 0.54 ± 0.07 at the activated state ( p  = 0.04, paired t test) within a functional localizer-defined volume of interest, and a decline in R 2 ' from 6.5 ± 1.3s −1 at baseline to 6.2 ± 1.4s −1 at the activated state ( p  = 0.006, paired t test) in the visual cortex. Conclusion The sqBOLD technique is sensitive enough to detect and quantify changes in oxygenation in the healthy brain and shows potential for integration into clinical settings to provide valuable information on oxygenation in glioma.
    Type of Medium: Online Resource
    ISSN: 1352-8661
    URL: Article
    DOI: 10.1007/s10334-023-01110-1
    Language: English
    Publisher: Springer Science and Business Media LLC
    Publication Date: 2023
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  • 4
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    Online Resource
    Microvasculature Features Derived from Hybrid EPI MRI in Non-Enhancing Adult-Type Diffuse Glioma Subtypes
    MDPI AG ; 2023
    In:  Cancers Vol. 15, No. 7 ( 2023-04-04), p. 2135-
    Details
    In: Cancers, MDPI AG, Vol. 15, No. 7 ( 2023-04-04), p. 2135-
    Abstract: In this study, we used the vessel size imaging (VSI) MRI technique to characterize the microvasculature features of three subtypes of adult-type diffuse glioma lacking enhancement. Thirty-eight patients with confirmed non-enhancing glioma were categorized into three subtypes: Oligo (IDH-mut & 1p/19q-codeleted), Astro (IDH-mut), and GBM (IDH-wt). The VSI technique provided quantitative maps of cerebral blood volume (CBV), microvasculature (µCBV), and vessel size for each patient. Additionally, tissue samples of 21 patients were histopathologically analyzed, and microvasculature features were quantified. Both MRI- and histology-derived features were compared across the three glioma subtypes with ANOVA or Kruskal–Wallis tests. Group averages of CBV, μCBV, and vessel size were significantly different between the three glioma subtypes (p 〈 0.01). Astro (IDH-mut) had a significantly lower CBV and µCBV compared to Oligo (IDH-mut & 1p/19q-codeleted) (p = 0.004 and p = 0.001, respectively), and a higher average vessel size compared to GBM (IDH-wt) (p = 0.01). The histopathological analysis showed that GBM (IDH-wt) possessed vessels with more irregular shapes than the two other subtypes (p 〈 0.05). VSI provides a good insight into the microvasculature characteristics of the three adult-type glioma subtypes even when lacking enhancement. Further investigations into the specificity of VSI to differentiate glioma subtypes are thus warranted.
    Type of Medium: Online Resource
    ISSN: 2072-6694
    URL: Article
    DOI: 10.3390/cancers15072135
    Language: English
    Publisher: MDPI AG
    Publication Date: 2023
    detail.hit.zdb_id: 2527080-1
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  • 5
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    Online Resource
    Mapping tumour heterogeneity with pulsed 3D CEST MRI in non-enhancing glioma at 3 T
    Springer Science and Business Media LLC ; 2022
    In:  Magnetic Resonance Materials in Physics, Biology and Medicine Vol. 35, No. 1 ( 2022-02), p. 53-62
    Details
    In: Magnetic Resonance Materials in Physics, Biology and Medicine, Springer Science and Business Media LLC, Vol. 35, No. 1 ( 2022-02), p. 53-62
    Abstract: Amide proton transfer (APT) weighted chemical exchange saturation transfer (CEST) imaging is increasingly used to investigate high-grade, enhancing brain tumours. Non-enhancing glioma is currently less studied, but shows heterogeneous pathophysiology with subtypes having equally poor prognosis as enhancing glioma. Here, we investigate the use of CEST MRI to best differentiate non-enhancing glioma from healthy tissue and image tumour heterogeneity. Materials & Methods A 3D pulsed CEST sequence was applied at 3 Tesla with whole tumour coverage and 31 off-resonance frequencies (+6 to -6 ppm) in 18 patients with non-enhancing glioma. Magnetisation transfer ratio asymmetry (MTRasym) and Lorentzian difference (LD) maps at 3.5 ppm were compared for differentiation of tumour versus normal appearing white matter. Heterogeneity was mapped by calculating volume percentages of the tumour showing hyperintense APT-weighted signal. Results LDamide gave greater effect sizes than MTRasym to differentiate non-enhancing glioma from normal appearing white matter. On average, 17.9 % ± 13.3 % (min–max: 2.4 %–54.5 %) of the tumour volume showed hyperintense LDamide in non-enhancing glioma. Conclusion This works illustrates the need for whole tumour coverage to investigate heterogeneity in increased APT-weighted CEST signal in non-enhancing glioma. Future work should investigate whether targeting hyperintense LDamide regions for biopsies improves diagnosis of non-enhancing glioma.
    Type of Medium: Online Resource
    ISSN: 0968-5243 , 1352-8661
    URL: Article
    DOI: 10.1007/s10334-021-00911-6
    Language: English
    Publisher: Springer Science and Business Media LLC
    Publication Date: 2022
    detail.hit.zdb_id: 1502491-X
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  • 6
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    Online Resource
    3D APT and NOE CEST-MRI of healthy volunteers and patients with non-enhancing glioma at 3 T
    Springer Science and Business Media LLC ; 2022
    In:  Magnetic Resonance Materials in Physics, Biology and Medicine Vol. 35, No. 1 ( 2022-02), p. 63-73
    Details
    In: Magnetic Resonance Materials in Physics, Biology and Medicine, Springer Science and Business Media LLC, Vol. 35, No. 1 ( 2022-02), p. 63-73
    Abstract: Clinical application of chemical exchange saturation transfer (CEST) can be performed with investigation of amide proton transfer (APT) and nuclear Overhauser enhancement (NOE) effects. Here, we investigated APT- and NOE-weighted imaging based on advanced CEST metrics to map tumor heterogeneity of non-enhancing glioma at 3 T. Materials and methods APT- and NOE-weighted maps based on Lorentzian difference (LD) and inverse magnetization transfer ratio (MTR REX ) were acquired with a 3D snapshot CEST acquisition at 3 T. Saturation power was investigated first by varying B 1 (0.5–2 µT) in 5 healthy volunteers then by applying B 1 of 0.5 and 1.5 µT in 10 patients with non-enhancing glioma. Tissue contrast (TC) and contrast-to-noise ratios (CNR) were calculated between glioma and normal appearing white matter (NAWM) and grey matter, in APT- and NOE-weighted images. Volume percentages of the tumor showing hypo/hyperintensity (VP hypo/hyper,CEST ) in APT/NOE-weighted images were calculated for each patient. Results LD APT resulting from using a B 1 of 1.5 µT was found to provide significant positive TC tumor,NAWM and MTR REX NOE ( B 1 of 1.5 µT) provided significant negative TC tumor,NAWM in tissue differentiation. MTR REX -based NOE imaging under 1.5 µT provided significantly larger VP hypo,CEST than MTR REX APT under 1.5 µT. Conclusion This work showed that with a rapid CEST acquisition using a B 1 saturation power of 1.5 µT and covering the whole tumor, analysis of both LD APT and MTR REX NOE allows for observing tumor heterogeneity, which will be beneficial in future studies using CEST-MRI to improve imaging diagnostics for non-enhancing glioma.
    Type of Medium: Online Resource
    ISSN: 0968-5243 , 1352-8661
    URL: Article
    DOI: 10.1007/s10334-021-00996-z
    Language: English
    Publisher: Springer Science and Business Media LLC
    Publication Date: 2022
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  • 7
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    Online Resource
    MR Vascular Fingerprinting with Hybrid Gradient–Spin Echo Dynamic Susceptibility Contrast MRI for Characterization of Microvasculature in Gliomas
    MDPI AG ; 2023
    In:  Cancers Vol. 15, No. 7 ( 2023-04-06), p. 2180-
    Details
    In: Cancers, MDPI AG, Vol. 15, No. 7 ( 2023-04-06), p. 2180-
    Abstract: Characterization of tumor microvasculature is important in tumor assessment and studying treatment response. This is possible by acquiring vascular biomarkers with magnetic resonance imaging (MRI) based on dynamic susceptibility contrast (DSC). We propose magnetic resonance vascular fingerprinting (MRVF) for hybrid echo planar imaging (HEPI) acquired during the first passage of the contrast agent (CA). The proposed approach was evaluated in patients with gliomas, and we simultaneously estimated vessel radius and relative cerebral blood volume. These parameters were also compared to the respective values estimated using the previously introduced vessel size imaging (VSI) technique. The results of both methods were found to be consistent. MRVF was also found to be robust to noise in the estimation of the parameters. DSC-HEPI-based MRVF provides characterization of microvasculature in gliomas with a short acquisition time and can be further improved in several ways to increase our understanding of tumor physiology.
    Type of Medium: Online Resource
    ISSN: 2072-6694
    URL: Article
    DOI: 10.3390/cancers15072180
    Language: English
    Publisher: MDPI AG
    Publication Date: 2023
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  • 8
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    Online Resource
    Recommendations for quantitative cerebral perfusion MRI using multi‐timepoint arterial spin labeling: Acquisition, quantification, and clinical applications
    Wiley ; 2024
    In:  Magnetic Resonance in Medicine
    Details
    In: Magnetic Resonance in Medicine, Wiley
    Abstract: Accurate assessment of cerebral perfusion is vital for understanding the hemodynamic processes involved in various neurological disorders and guiding clinical decision‐making. This guidelines article provides a comprehensive overview of quantitative perfusion imaging of the brain using multi‐timepoint arterial spin labeling (ASL), along with recommendations for its acquisition and quantification. A major benefit of acquiring ASL data with multiple label durations and/or post‐labeling delays (PLDs) is being able to account for the effect of variable arterial transit time (ATT) on quantitative perfusion values and additionally visualize the spatial pattern of ATT itself, providing valuable clinical insights. Although multi‐timepoint data can be acquired in the same scan time as single‐PLD data with comparable perfusion measurement precision, its acquisition and postprocessing presents challenges beyond single‐PLD ASL, impeding widespread adoption. Building upon the 2015 ASL consensus article, this work highlights the protocol distinctions specific to multi‐timepoint ASL and provides robust recommendations for acquiring high‐quality data. Additionally, we propose an extended quantification model based on the 2015 consensus model and discuss relevant postprocessing options to enhance the analysis of multi‐timepoint ASL data. Furthermore, we review the potential clinical applications where multi‐timepoint ASL is expected to offer significant benefits. This article is part of a series published by the International Society for Magnetic Resonance in Medicine (ISMRM) Perfusion Study Group, aiming to guide and inspire the advancement and utilization of ASL beyond the scope of the 2015 consensus article.
    Type of Medium: Online Resource
    ISSN: 0740-3194 , 1522-2594
    URL: Article
    DOI: 10.1002/mrm.30091
    Language: English
    Publisher: Wiley
    Publication Date: 2024
    detail.hit.zdb_id: 1493786-4
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  • 9
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    Online Resource
    Micro- to macroscale magnetic resonance imaging of glioma
    Springer Science and Business Media LLC ; 2022
    In:  Magnetic Resonance Materials in Physics, Biology and Medicine Vol. 35, No. 1 ( 2022-02), p. 1-2
    Details
    In: Magnetic Resonance Materials in Physics, Biology and Medicine, Springer Science and Business Media LLC, Vol. 35, No. 1 ( 2022-02), p. 1-2
    Type of Medium: Online Resource
    ISSN: 0968-5243 , 1352-8661
    URL: Article
    DOI: 10.1007/s10334-021-00999-w
    Language: English
    Publisher: Springer Science and Business Media LLC
    Publication Date: 2022
    detail.hit.zdb_id: 1502491-X
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  • 10
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    Online Resource
    Arterial spin labelling MRI for brain tumour surveillance: do we really need cerebral blood flow maps?
    Springer Science and Business Media LLC ; 2023
    In:  European Radiology
    Details
    In: European Radiology, Springer Science and Business Media LLC
    Abstract: Arterial spin labelling (ASL) perfusion MRI is one of the available advanced MRI techniques for brain tumour surveillance. The first aim of this study was to investigate the correlation between quantitative cerebral blood flow (CBF) and non-quantitative perfusion weighted imaging (ASL-PWI) measurements. The second aim was to investigate the diagnostic accuracy of ASL-CBF and ASL-PWI measurements as well as visual assessment for identifying tumour progression. Methods A consecutive cohort of patients who underwent 3-T MRI surveillance containing ASL for treated brain tumours was used. ROIs were drawn in representative parts of tumours in the ASL-CBF maps and copied to the ASL-PWI. ASL-CBF ratios and ASL-PWI ratios of the tumour ROI versus normal appearing white matter (NAWM) were correlated (Pearson correlation) and AUCs were calculated to assess diagnostic accuracy. Additionally, lesions were visually classified as hypointense, isointense, or hyperintense. We calculated accuracy at two thresholds: low threshold (between hypointense-isointense) and high threshold (between isointense-hyperintense). Results A total of 173 lesions, both enhancing and non-enhancing, measured in 115 patients (93 glioma, 16 metastasis, and 6 lymphoma) showed a very high correlation of 0.96 (95% CI: 0.88–0.99) between ASL-CBF ratios and ASL-PWI ratios. AUC was 0.76 (95%CI: 0.65–0.88) for ASL-CBF ratios and 0.72 (95%CI: 0.58–0.85) for ASL-PWI ratios. Diagnostic accuracy of visual assessment for enhancing lesions was 0.72. Conclusion ASL-PWI ratios and ASL-CBF ratios showed a high correlation and comparable AUCs; therefore, quantification of ASL-CBF could be omitted in these patients. Visual classification had comparable diagnostic accuracy to the ASL-PWI or ASL-CBF ratios. Clinical relevance statement This study shows that CBF quantification of ASL perfusion MRI could be omitted for brain tumour surveillance and that visual assessment provides the same diagnostic accuracy. This greatly reduces the complexity of the use of ASL in routine clinical practice. Key Points • Arterial spin labelling MRI for clinical brain tumour surveillance is undervalued and underinvestigated. • Non-quantitative and quantitative arterial spin labelling assessments show high correlation and comparable diagnostic accuracy. • Quantification of arterial spin labelling MRI could be omitted to improve daily clinical workflow.
    Type of Medium: Online Resource
    ISSN: 1432-1084
    URL: Article
    DOI: 10.1007/s00330-023-10099-z
    Language: English
    Publisher: Springer Science and Business Media LLC
    Publication Date: 2023
    detail.hit.zdb_id: 1472718-3
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