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  1. Article ; Online: Quantitative Delta T1 (dT1) as a Replacement for Adjudicated Central Reader Analysis of Contrast-Enhancing Tumor Burden: A Subanalysis of the American College of Radiology Imaging Network 6677/Radiation Therapy Oncology Group 0625 Multicenter Brain Tumor Trial.

    Schmainda, K M / Prah, M A / Zhang, Z / Snyder, B S / Rand, S D / Jensen, T R / Barboriak, D P / Boxerman, J L

    AJNR. American journal of neuroradiology

    2019  Volume 40, Issue 7, Page(s) 1132–1139

    Abstract: Background and purpose: Brain tumor clinical trials requiring solid tumor assessment typically rely on the 2D manual delineation of enhancing tumors by ≥2 expert readers, a time-consuming step with poor interreader agreement. As a solution, we developed ...

    Abstract Background and purpose: Brain tumor clinical trials requiring solid tumor assessment typically rely on the 2D manual delineation of enhancing tumors by ≥2 expert readers, a time-consuming step with poor interreader agreement. As a solution, we developed quantitative dT1 maps for the delineation of enhancing lesions. This retrospective analysis compares dT1 with 2D manual delineation of enhancing tumors acquired at 2 time points during the post therapeutic surveillance period of the American College of Radiology Imaging Network 6677/Radiation Therapy Oncology Group 0625 (ACRIN 6677/RTOG 0625) clinical trial.
    Materials and methods: Patients enrolled in ACRIN 6677/RTOG 0625, a multicenter, randomized Phase II trial of bevacizumab in recurrent glioblastoma, underwent standard MR imaging before and after treatment initiation. For 123 patients from 23 institutions, both 2D manual delineation of enhancing tumors and dT1 datasets were evaluable at weeks 8 (
    Results: For identification of progression, dT1 and adjudicated 2D manual delineation of enhancing tumor reads were in perfect agreement at week 8, with 73.7% agreement at week 16. Both methods showed significant differences in overall survival at each time point. When nonprogressors were further divided into responders versus nonresponders/nonprogressors, the agreement decreased to 70.3% and 52.6%, yet dT1 showed a significant difference in overall survival at week 8 (
    Conclusions: This study shows that dT1 can predict early progression comparable with the standard method but offers the potential for substantial time and cost savings for clinical trials.
    MeSH term(s) Adult ; Aged ; Antineoplastic Agents, Immunological/therapeutic use ; Bevacizumab/therapeutic use ; Brain Neoplasms/diagnostic imaging ; Brain Neoplasms/drug therapy ; Brain Neoplasms/pathology ; Female ; Glioblastoma/diagnostic imaging ; Glioblastoma/drug therapy ; Glioblastoma/pathology ; Humans ; Image Interpretation, Computer-Assisted/methods ; Magnetic Resonance Imaging/methods ; Male ; Middle Aged ; Neuroimaging/methods ; Retrospective Studies ; Tumor Burden
    Chemical Substances Antineoplastic Agents, Immunological ; Bevacizumab (2S9ZZM9Q9V)
    Language English
    Publishing date 2019-06-27
    Publishing country United States
    Document type Clinical Trial, Phase II ; Journal Article ; Multicenter Study ; Randomized Controlled Trial ; Research Support, Non-U.S. Gov't
    ZDB-ID 603808-6
    ISSN 1936-959X ; 0195-6108
    ISSN (online) 1936-959X
    ISSN 0195-6108
    DOI 10.3174/ajnr.A6110
    Database MEDical Literature Analysis and Retrieval System OnLINE

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    Zs.A 1580: Show issues Location:
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  2. Article ; Online: The effect of pulse sequence parameters and contrast agent dose on percentage signal recovery in DSC-MRI: implications for clinical applications.

    Boxerman, J L / Paulson, E S / Prah, M A / Schmainda, K M

    AJNR. American journal of neuroradiology

    2013  Volume 34, Issue 7, Page(s) 1364–1369

    Abstract: Background and purpose: Both technical and pathophysiologic factors affect PSR in DSC-MR imaging. We aimed to determine how TE, flip angle (α), and contrast dose impact PSR in high-grade gliomas.: Materials and methods: We retrospectively computed ... ...

    Abstract Background and purpose: Both technical and pathophysiologic factors affect PSR in DSC-MR imaging. We aimed to determine how TE, flip angle (α), and contrast dose impact PSR in high-grade gliomas.
    Materials and methods: We retrospectively computed PSR maps for 22 patients with high-grade gliomas, comparing 3 DSC-MR imaging methods by using single-dose gadodiamide without preload administration: A (n = 7), α = 35°, TE = 54 ms; B (n = 5), α = 72°, TE = 30 ms; C (n = 10), α = 90°, TE = 30 ms. Methods A-C served as preload for subsequent dynamic imaging using method D (method C parameters but with double-dose contrast). We compared first- and second-injection tumor PSR for methods C and D (paired t test) and tumor PSR for both injections grouped by the first-injection acquisition method (3-group nonparametric 1-way ANOVA). We compared PSR in tumor and normal brain for each first- and second-injection method group (paired t test).
    Results: First-injection PSR in tumor and normal brain differed significantly for methods B (P = .01) and C (P = .05), but not A (P = .71). First-injection tumor PSR increased with T1 weighting with a significant main effect of method groupings (P = .0012), but there was no significant main effect for first-injection normal brain (P = .93), or second-injection tumor (P = .95) or normal brain (P = .13). In patients scanned with methods C and D, first-injection PSR significantly exceeded second-injection PSR for tumor (P = .037) and normal brain (P < .001).
    Conclusions: PSR strongly depends on the T1 weighting of DSC-MR imaging, including pulse sequence (TE, α) and contrast agent (dose, preload) parameters, with implications for protocol design and the interpretation and comparison of PSR values across tumor types and imaging centers.
    MeSH term(s) Adult ; Aged ; Algorithms ; Astrocytoma/diagnosis ; Brain/pathology ; Brain Neoplasms/diagnosis ; Cohort Studies ; Contrast Media/administration & dosage ; Female ; Gadolinium DTPA/administration & dosage ; Glioblastoma/diagnosis ; Glioma/diagnosis ; Humans ; Image Enhancement/methods ; Injections, Intravenous ; Magnetic Resonance Imaging/methods ; Male ; Middle Aged ; Neoplasm Recurrence, Local/diagnosis ; Oligodendroglioma/diagnosis ; Retrospective Studies ; Young Adult
    Chemical Substances Contrast Media ; gadodiamide (84F6U3J2R6) ; Gadolinium DTPA (K2I13DR72L)
    Language English
    Publishing date 2013-02-14
    Publishing country United States
    Document type Comparative Study ; Journal Article ; Research Support, N.I.H., Extramural ; Research Support, Non-U.S. Gov't
    ZDB-ID 603808-6
    ISSN 1936-959X ; 0195-6108
    ISSN (online) 1936-959X
    ISSN 0195-6108
    DOI 10.3174/ajnr.A3477
    Database MEDical Literature Analysis and Retrieval System OnLINE

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    Zs.A 1580: Show issues Location:
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  3. Article ; Online: Moving Toward a Consensus DSC-MRI Protocol: Validation of a Low-Flip Angle Single-Dose Option as a Reference Standard for Brain Tumors.

    Schmainda, K M / Prah, M A / Hu, L S / Quarles, C C / Semmineh, N / Rand, S D / Connelly, J M / Anderies, B / Zhou, Y / Liu, Y / Logan, B / Stokes, A / Baird, G / Boxerman, J L

    AJNR. American journal of neuroradiology

    2019  Volume 40, Issue 4, Page(s) 626–633

    Abstract: Background and purpose: DSC-MR imaging using preload, intermediate (60°) flip angle and postprocessing leakage correction has gained traction as a standard methodology. Simulations suggest that DSC-MR imaging with flip angle = 30° and no preload yields ... ...

    Abstract Background and purpose: DSC-MR imaging using preload, intermediate (60°) flip angle and postprocessing leakage correction has gained traction as a standard methodology. Simulations suggest that DSC-MR imaging with flip angle = 30° and no preload yields relative CBV practically equivalent to the reference standard. This study tested this hypothesis in vivo.
    Materials and methods: Eighty-four patients with brain lesions were enrolled in this 3-institution study. Forty-three patients satisfied the inclusion criteria. DSC-MR imaging (3T, single-dose gadobutrol, gradient recalled-echo-EPI, TE = 20-35 ms, TR = 1.2-1.63 seconds) was performed twice for each patient, with flip angle = 30°-35° and no preload (P-), which provided preload (P+) for the subsequent intermediate flip angle = 60°. Normalized relative CBV and standardized relative CBV maps were generated, including postprocessing with contrast agent leakage correction (C+) and without (C-) contrast agent leakage correction. Contrast-enhancing lesion volume, mean relative CBV, and contrast-to-noise ratio obtained with 30°/P-/C-, 30°/P-/C+, and 60°/P+/C- were compared with 60°/P+/C+ using the Lin concordance correlation coefficient and Bland-Altman analysis. Equivalence between the 30°/P-/C+ and 60°/P+/C+ protocols and the temporal SNR for the 30°/P- and 60°/P+ DSC-MR imaging data was also determined.
    Results: Compared with 60°/P+/C+, 30°/P-/C+ had closest mean standardized relative CBV (
    Conclusions: Tumor relative CBV derived from low-flip angle, no-preload DSC-MR imaging with leakage correction is an attractive single-dose alternative to the higher dose reference standard.
    MeSH term(s) Adult ; Brain Neoplasms/diagnostic imaging ; Brain Neoplasms/pathology ; Consensus ; Contrast Media ; Female ; Humans ; Image Interpretation, Computer-Assisted/methods ; Image Interpretation, Computer-Assisted/standards ; Magnetic Resonance Imaging/methods ; Magnetic Resonance Imaging/standards ; Male ; Neuroimaging/methods ; Neuroimaging/standards ; Organometallic Compounds ; Reference Standards
    Chemical Substances Contrast Media ; Organometallic Compounds ; gadobutrol (1BJ477IO2L)
    Language English
    Publishing date 2019-03-28
    Publishing country United States
    Document type Journal Article ; Research Support, N.I.H., Extramural ; Validation Study
    ZDB-ID 603808-6
    ISSN 1936-959X ; 0195-6108
    ISSN (online) 1936-959X
    ISSN 0195-6108
    DOI 10.3174/ajnr.A6015
    Database MEDical Literature Analysis and Retrieval System OnLINE

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    ab Jg. 2022: Lesesaal (EG)

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  4. Article ; Online: Repeatability of Standardized and Normalized Relative CBV in Patients with Newly Diagnosed Glioblastoma.

    Prah, M A / Stufflebeam, S M / Paulson, E S / Kalpathy-Cramer, J / Gerstner, E R / Batchelor, T T / Barboriak, D P / Rosen, B R / Schmainda, K M

    AJNR. American journal of neuroradiology

    2015  Volume 36, Issue 9, Page(s) 1654–1661

    Abstract: Background and purpose: For more widespread clinical use advanced imaging methods such as relative cerebral blood volume must be both accurate and repeatable. The aim of this study was to determine the repeatability of relative CBV measurements in newly ...

    Abstract Background and purpose: For more widespread clinical use advanced imaging methods such as relative cerebral blood volume must be both accurate and repeatable. The aim of this study was to determine the repeatability of relative CBV measurements in newly diagnosed glioblastoma multiforme by using several of the most commonly published estimation techniques.
    Materials and methods: The relative CBV estimates were calculated from dynamic susceptibility contrast MR imaging in double-baseline examinations for 33 patients with treatment-naïve and pathologically proved glioblastoma multiforme (men = 20; mean age = 55 years). Normalized and standardized relative CBV were calculated by using 6 common postprocessing methods. The repeatability of both normalized and standardized relative CBV, in both tumor and contralateral brain, was examined for each method with metrics of repeatability, including the repeatability coefficient and within-subject coefficient of variation. The minimum sample size required to detect a parameter change of 10% or 20% was also determined for both normalized relative CBV and standardized relative CBV for each estimation method.
    Results: When ordered by the repeatability coefficient, methods using postprocessing leakage correction and ΔR2*(t) techniques offered superior repeatability. Across processing techniques, the standardized relative CBV repeatability in normal-appearing brain was comparable with that in tumor (P = .31), yet inferior in tumor for normalized relative CBV (P = .03). On the basis of the within-subject coefficient of variation, tumor standardized relative CBV estimates were less variable (13%-20%) than normalized relative CBV estimates (24%-67%). The minimum number of participants needed to detect a change of 10% or 20% is 118-643 or 30-161 for normalized relative CBV and 109-215 or 28-54 for standardized relative CBV.
    Conclusions: The ΔR2* estimation methods that incorporate leakage correction offer the best repeatability for relative CBV, with standardized relative CBV being less variable and requiring fewer participants to detect a change compared with normalized relative CBV.
    MeSH term(s) Adult ; Aged ; Blood Volume Determination/methods ; Blood Volume Determination/standards ; Brain Neoplasms/physiopathology ; Female ; Glioblastoma/physiopathology ; Humans ; Magnetic Resonance Imaging ; Male ; Middle Aged ; Reference Standards
    Language English
    Publishing date 2015-09
    Publishing country United States
    Document type Journal Article ; Research Support, N.I.H., Extramural
    ZDB-ID 603808-6
    ISSN 1936-959X ; 0195-6108
    ISSN (online) 1936-959X
    ISSN 0195-6108
    DOI 10.3174/ajnr.A4374
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  5. Article ; Online: Multisite Concordance of DSC-MRI Analysis for Brain Tumors: Results of a National Cancer Institute Quantitative Imaging Network Collaborative Project.

    Schmainda, K M / Prah, M A / Rand, S D / Liu, Y / Logan, B / Muzi, M / Rane, S D / Da, X / Yen, Y-F / Kalpathy-Cramer, J / Chenevert, T L / Hoff, B / Ross, B / Cao, Y / Aryal, M P / Erickson, B / Korfiatis, P / Dondlinger, T / Bell, L /
    Hu, L / Kinahan, P E / Quarles, C C

    AJNR. American journal of neuroradiology

    2018  Volume 39, Issue 6, Page(s) 1008–1016

    Abstract: Background and purpose: Standard assessment criteria for brain tumors that only include anatomic imaging continue to be insufficient. While numerous studies have demonstrated the value of DSC-MR imaging perfusion metrics for this purpose, they have not ... ...

    Abstract Background and purpose: Standard assessment criteria for brain tumors that only include anatomic imaging continue to be insufficient. While numerous studies have demonstrated the value of DSC-MR imaging perfusion metrics for this purpose, they have not been incorporated due to a lack of confidence in the consistency of DSC-MR imaging metrics across sites and platforms. This study addresses this limitation with a comparison of multisite/multiplatform analyses of shared DSC-MR imaging datasets of patients with brain tumors.
    Materials and methods: DSC-MR imaging data were collected after a preload and during a bolus injection of gadolinium contrast agent using a gradient recalled-echo-EPI sequence (TE/TR = 30/1200 ms; flip angle = 72°). Forty-nine low-grade (
    Results: For normalized relative CBV and normalized CBF, 93% and 94% of entries showed good or excellent cross-site agreement (0.8 ≤ Lin concordance correlation coefficient ≤ 1.0). All metrics could distinguish low- from high-grade tumors. Optimum thresholds were determined for pooled data (normalized relative CBV = 1.4, sensitivity/specificity = 90%:77%; normalized CBF = 1.58, sensitivity/specificity = 86%:77%).
    Conclusions: By means of DSC-MR imaging data obtained after a preload of contrast agent, substantial consistency resulted across sites for brain tumor perfusion metrics with a common threshold discoverable for distinguishing low- from high-grade tumors.
    MeSH term(s) Adult ; Aged ; Algorithms ; Brain Neoplasms/diagnostic imaging ; Brain Neoplasms/pathology ; Datasets as Topic/standards ; Female ; Glioma/diagnostic imaging ; Glioma/pathology ; Humans ; Image Interpretation, Computer-Assisted/methods ; Image Interpretation, Computer-Assisted/standards ; Magnetic Resonance Imaging/standards ; Male ; Middle Aged ; National Cancer Institute (U.S.) ; United States
    Language English
    Publishing date 2018-05-24
    Publishing country United States
    Document type Journal Article ; Research Support, N.I.H., Extramural ; Research Support, Non-U.S. Gov't
    ZDB-ID 603808-6
    ISSN 1936-959X ; 0195-6108
    ISSN (online) 1936-959X
    ISSN 0195-6108
    DOI 10.3174/ajnr.A5675
    Database MEDical Literature Analysis and Retrieval System OnLINE

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