7 results on '"Kim, Sang Joon"'
Search Results
2. Advanced imaging parameters improve the prediction of diffuse lower-grade gliomas subtype, IDH mutant with no 1p19q codeletion: added value to the T2/FLAIR mismatch sign.
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Lee, Min Kyoung, Park, Ji Eun, Jo, Youngheun, Park, Seo Young, Kim, Sang Joon, and Kim, Ho Sung
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OLIGODENDROGLIOMAS ,RECEIVER operating characteristic curves ,REGRESSION analysis ,DIFFUSION magnetic resonance imaging ,BLOOD volume ,CHROMOSOMES ,GENETIC mutation ,GLIOMAS ,MAGNETIC resonance imaging ,BRAIN tumors ,RESEARCH funding ,OXIDOREDUCTASES ,TUMOR grading - Abstract
Objectives: A combination of T2/FLAIR mismatch sign and advanced imaging parameters may improve the determination of molecular subtypes of diffuse lower-grade glioma. We assessed the diagnostic value of adding the apparent diffusion coefficient (ADC) and cerebral blood volume (CBV) to the T2/FLAIR mismatch sign for differentiation of the IDH mutation or 1p/19q codeletion.Materials and Methods: Preoperative conventional, diffusion-weighted, and dynamic susceptibility contrast imaging were performed on 110 patients with diffuse lower-grade gliomas. The study population was classified into three groups using molecular subtype, namely IDH mutation and 1p/19q codeletion (IDHmut-Codel), IDH wild type (IDHwt) and IDH mutation and no 1p/19q codeletion (IDHmut-Noncodel). T2/FLAIR mismatch sign and the histogram parameters of apparent diffusion coefficient (ADC) and normalised cerebral blood volume (nCBV) values were assessed. A multivariate logistic regression model was constructed to distinguish IDHmut-Noncodel from IDHmut-Codel and IDHwt and from IDHwt, and the performance was compared with that of single parameters using the area under the receiver operating characteristics curve (AUC).Results: Positive visual T2/FLAIR mismatch sign and higher nCBV skewness were significant variables to distinguish IDHmut-Noncodel from the other two groups (AUC, 0.88; 95% CI, 0.81-0.96). A lower ADC10 was a significant variable for distinguishing IDHmut-Noncodel from the IDHwt group (AUC, 0.75; 95% CI, 0.62-0.89). Adding ADC or CBV histogram parameters to T2/FLAIR mismatch sign improved performance in distinguishing IDHmut-Noncodel from the other two groups (AUC 0.882 vs. AUC 0.810) or from IDHwt (AUC 0.923 vs. AUC 0.868).Conclusions: The combination of the T2/FLAIR mismatch sign with ADC or CBV histogram parameters can improve the identification of IDHmut-Noncodel diffuse lower-grade gliomas, which can be easily applied in clinical practice.Key Points: • The combination of the T2/FLAIR mismatch sign with the ADC or CBV histogram parameters can improve the identification of IDHmut-Noncodel diffuse lower-grade gliomas. • The multivariable model showed a significantly better performance for distinguishing the IDHmut-Noncodel group from other diffuse lower-grade gliomas than the T2/FLAIR mismatch sign alone or any single parameter. • The IDHmut-Noncodel type was associated with intermediate treatment outcomes; therefore, the identification of IDHmut-Noncodel diffuse lower-grade gliomas could be helpful for determining the clinical approach. [ABSTRACT FROM AUTHOR]- Published
- 2020
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3. Prognostic relevance of gemistocytic grade II astrocytoma: gemistocytic component and MR imaging features compared to non-gemistocytic grade II astrocytoma.
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Heo, Young, Park, Ji, Kim, Ho, Lee, Ji, Nam, Soo, Jung, Seung, Choi, Choong, Kim, Sang, Heo, Young Jin, Park, Ji Eun, Kim, Ho Sung, Lee, Ji Ye, Nam, Soo Jeong, Jung, Seung Chai, Choi, Choong Gon, and Kim, Sang Joon
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ASTROCYTOMAS ,TUMOR grading ,DISEASE progression ,TUMORS ,HISTOPATHOLOGY ,CONTRAST-enhanced magnetic resonance imaging ,PROGNOSIS ,MAGNETIC resonance imaging ,BRAIN tumors ,COMPARATIVE studies ,GLIOMAS ,LONGITUDINAL method ,RESEARCH methodology ,MEDICAL cooperation ,NUCLEAR magnetic resonance spectroscopy ,RESEARCH ,TIME ,EVALUATION research ,RETROSPECTIVE studies - Abstract
Objectives: To determine if gemistocytic grade II astrocytoma (GemA) and its MR imaging characteristics are associated with a shorter time-to-progression (TTP) compared with non-gemistocytic grade II astrocytoma (non-GemA).Materials and Methods: We enrolled 78 patients who were followed up more than 5 years (29 pathologically proven GemA and 49 non-GemA) during a 10-year period. Contrast-enhanced T1-weighted, diffusion-weighted imaging (DWI), dynamic susceptibility contrast (DSC), and MR spectroscopy (MRS) and clinical data were retrospectively reviewed. Clinical and MR imaging features were analyzed as possible prognostic factors of high-grade transformation, and multivariate analysis of TTP was performed using Cox proportional modeling.Results: GemA showed more frequent high-grade features than non-GemA, including diffusion restriction (P < .001), increased choline/creatine (P = .02), and increased choline/NAA ratio (P = .015). Patients with GemA had a significantly shorter median TTP (53.1 vs 68 months; P < .001). A gemistocytic histopathology (hazard ratio = 3.42; P = .015) and low ADC (hazard ratio = 3.61; P = .001) were independently associated with a shorter TTP.Conclusions: GemA can present with MR imaging findings mimicking high-grade glioma at initial diagnosis and transforms to high-grade disease earlier than non-GemA. Low ADC on DWI might be useful in stratifying the risk of progression in patients with grade II astrocytoma.Key Points: • Gemistocytic grade II astrocytoma (GemA) showed more frequent high-grade features than non-GemA. • Patients with GemA had a significantly shorter median TTP than non-GemA. • Gemistocytic histopathology and low ADC were independently associated with shorter TTP. [ABSTRACT FROM AUTHOR]- Published
- 2017
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4. Different diagnostic values of imaging parameters to predict pseudoprogression in glioblastoma subgroups stratified by MGMT promoter methylation.
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Yoon, Ra, Kim, Ho, Paik, Wooyul, Shim, Woo, Kim, Sang, Kim, Jeong, Yoon, Ra Gyoung, Kim, Ho Sung, Shim, Woo Hyun, Kim, Sang Joon, and Kim, Jeong Hoon
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GLIOBLASTOMA multiforme ,DNA methyltransferases ,METHYLATION ,MAGNETIC resonance imaging ,CHEMORADIOTHERAPY ,DIAGNOSIS ,BRAIN tumors ,DNA ,ENZYMES ,GENES ,GLIOMAS ,PHARMACOKINETICS ,PROTEINS ,RETROSPECTIVE studies ,RECEIVER operating characteristic curves ,DISEASE progression ,DNA methylation - Abstract
Objectives: The aim of this study was to determine whether diffusion and perfusion imaging parameters demonstrate different diagnostic values for predicting pseudoprogression between glioblastoma subgroups stratified by O6-mythylguanine-DNA methyltransferase (MGMT) promoter methylation status.Methods: We enrolled seventy-five glioblastoma patients that had presented with enlarged contrast-enhanced lesions on magnetic resonance imaging (MRI) one month after completing concurrent chemoradiotherapy and undergoing MGMT promoter methylation testing. The imaging parameters included 10 or 90 % histogram cutoffs of apparent diffusion coefficient (ADC10), normalized cerebral blood volume (nCBV90), and initial area under the time signal-intensity curve (IAUC90). The results of the areas under the receiver operating characteristic curve (AUCs) with cross-validation were compared between MGMT methylation and unmethylation groups.Results: MR imaging parameters demonstrated a trend toward higher accuracy in the MGMT promoter methylation group than in the unmethylation group (cross-validated AUCs = 0.70-0.95 and 0.56-0.87, respectively). The combination of MGMT methylation status with imaging parameters improved the AUCs from 0.70 to 0.75-0.90 for both readers in comparison with MGMT methylation status alone. The probability of pseudoprogression was highest (95.7 %) when nCBV90 was below 4.02 in the MGMT promoter methylation group.Conclusions: MR imaging parameters could be stronger predictors of pseudoprogression in glioblastoma patients with the methylated MGMT promoter than in patients with the unmethylated MGMT promoter.Key Points: • The glioblastoma subgroup was stratified according to MGMT promoter methylation status. • Diagnostic values of diffusion and perfusion parameters for predicting pseudoprogression were compared. • Imaging parameters showed higher diagnostic accuracy in the MGMT promoter methylation group. • Imaging parameters were independent to MGMT promoter methylation status for predicting pseudoprogression. • Imaging biomarkers might demonstrate different diagnostic values according to MGMT promoter methylation. [ABSTRACT FROM AUTHOR]- Published
- 2017
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5. Added value of amide proton transfer imaging to conventional and perfusion MR imaging for evaluating the treatment response of newly diagnosed glioblastoma.
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Park, Kye, Kim, Ho, Park, Ji, Shim, Woo, Kim, Sang, Smith, Seth, Park, Kye Jin, Kim, Ho Sung, Park, Ji Eun, Shim, Woo Hyun, Kim, Sang Joon, and Smith, Seth A
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PROTON transfer reactions ,MAGNETIC resonance imaging ,GLIOBLASTOMA multiforme ,GLIOBLASTOMA multiforme treatment ,CHEMORADIOTHERAPY ,PATIENTS ,BRAIN tumor treatment ,GLIOMA treatment ,AMIDES ,BRAIN tumors ,COMPARATIVE studies ,GLIOMAS ,RESEARCH methodology ,MEDICAL cooperation ,PROTONS ,RESEARCH ,EVALUATION research ,TREATMENT effectiveness ,CONTRAST media ,RECEIVER operating characteristic curves - Abstract
Objectives: To determine the added value of amide proton transfer (APT) imaging to conventional and perfusion MRI for differentiating tumour progression (TP) from the treatment-related effect (TE) in patients with post-treatment glioblastomas.Methods: Sixty-five consecutive patients with enlarging contrast-enhancing lesions following concurrent chemoradiotherapy were assessed using contrast-enhanced T1-weighted MRI (CE-T1WI), 90th percentile histogram parameters of normalized cerebral blood volume (nCBV90) and APT asymmetry value (APT90). Diagnostic performance was determined using the area under the receiver operating characteristic curve (AUC) and cross validations.Results: There were statistically significant differences in the mean APT90 between the TP and the TE groups (3.87-4.01 % vs. 1.38-1.41 %; P < .001). Compared with CE-T1WI alone, the addition of APT90 to CE-T1WI significantly improved cross-validated AUC from 0.58-0.74 to 0.89-0.91 for differentiating TP from TE. The combination of CE-T1WI, nCBV90 and APT90 resulted in greater diagnostic accuracy for differentiating TP from TE than the combination of CE-T1WI and nCBV90 (cross-validated AUC, 0.95-0.97 vs. 0.84-0.91). The inter-reader agreement between the expert and trainee was excellent for the measurements of APT90 (intraclass correlation coefficient, 0.94).Conclusion: Adding APT imaging to conventional and perfusion MRI improves the diagnostic performance for differentiating TP from TE.Key Points: • APT imaging could provide a reliable distinction between TP and TE • Adding APT imaging to CE-T1WI improved the diagnostic accuracy versus CE-T1WI alone • Multimodal imaging using CE-T1WI, perfusion and APT imaging led to accurate diagnosis • The inter-reader agreement of APT histogram parameters was excellent. [ABSTRACT FROM AUTHOR]- Published
- 2016
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6. Apparent diffusion coefficient parametric response mapping MRI for follow-up of glioblastoma.
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Yoon, Ra, Kim, Ho, Kim, Dae, Hong, Gil, Kim, Sang, Yoon, Ra Gyoung, Kim, Ho Sung, Kim, Dae Yoon, Hong, Gil Sun, and Kim, Sang Joon
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GLIOBLASTOMA multiforme treatment ,MAGNETIC resonance imaging of the brain ,DIFFUSION coefficients ,HISTOGRAMS ,RECEIVER operating characteristic curves ,BRAIN tumor treatment ,GLIOMA treatment ,BRAIN tumors ,BRAIN mapping ,GLIOMAS ,LONGITUDINAL method ,MAGNETIC resonance imaging ,RESEARCH evaluation ,TREATMENT effectiveness ,RETROSPECTIVE studies - Abstract
Objectives: To determine the diagnostic superiority of parametric response mapping of apparent diffusion coefficient (ADCPR) for predicting glioblastoma treatment response, compared to single time point measurement.Methods: Fifty post-treatment glioblastoma patients were enrolled. ADCPR was calculated from serial apparent diffusion coefficient (ADC) maps acquired before and at the time of first detection of an enlarged contrast-enhancing lesion on voxel-by-voxel basis. The percentage-decrease in ADCPR and tenth percentile histogram cutoff value of ADC (ADC10) were compared at subsequent 3-month and 1-year follow-ups.Results: The percentage-decrease in ADCPR was significantly higher in the progression group (mean = 33.2-38.3 %) than in the stable-response group (mean = 9.7 %) at 3 months follow-up (corrected p < 0.001 for both readers). ADCPR significantly improved area under the receiver operating characteristic curve from 0.67 to 0.88 (corrected p = 0.037) and from 0.70 to 0.92 (corrected p = 0.020) for both readers, respectively, compared to ADC10 at 3-month follow-up, but did not significantly improve at 1-year follow-up. The inter-reader agreement was higher for ADCPR than ADC10 (intraclass correlation coefficient, 0.93 versus 0.86).Conclusion: Voxel-based ADCPR appears to be a superior imaging biomarker than ADC, particularly for predicting early tumour progression in patients with glioblastoma.Key Points: • Treatment response pattern of glioblastoma was evaluated using voxel-based ADCPR and ADC10. • Voxel-based ADCPR was more accurate in predicting treatment response pattern than ADC10. • Inter-reader agreement was higher in ADCPR calculation than in ADC10 calculation. • Voxel-based ADCPR can be a predictor of early treatment response pattern for glioblastoma. [ABSTRACT FROM AUTHOR]- Published
- 2016
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7. Comparison of Apparent Diffusion Coefficient and Intravoxel Incoherent Motion for Differentiating among Glioblastoma, Metastasis, and Lymphoma Focusing on Diffusion-Related Parameter.
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Shim, Woo Hyun, Kim, Ho Sung, Choi, Choong-Gon, and Kim, Sang Joon
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DIFFUSION coefficients ,GLIOBLASTOMA multiforme ,PARAMETER estimation ,COMPARATIVE studies ,BRAIN tumors - Abstract
Background and Purpose: Brain tumor cellularity has been assessed by using apparent diffusion coefficient (ADC). However, the ADC value might be influenced by both perfusion and true molecular diffusion, and the perfusion effect on ADC can limit the reliability of ADC in the characterization of tumor cellularity, especially, in hypervascular brain tumors. In contrast, the IVIM technique estimates parameter values for diffusion and perfusion effects separately. The purpose of our study was to compare ADC and IVIM for differentiating among glioblastoma, metastatic tumor, and primary CNS lymphoma (PCNSL) focusing on diffusion-related parameter. Materials and Methods: We retrospectively reviewed the data of 128 patients with pathologically confirmed glioblastoma (n = 55), metastasis (n = 31), and PCNSL (n = 42) prior to any treatment. Two neuroradiologists independently calculated the maximum IVIM-f (f
max ) and minimum IVIM-D (Dmin ) by using 16 different b-values with a bi-exponential fitting of diffusion signal decay, minimum ADC (ADCmin ) by using 0 and 1000 b-values with a mono-exponential fitting and maximum normalized cerebral blood volume (nCBVmax ). The differences in fmax , Dmin , nCBVmax, and ADCmin among the three tumor pathologies were determined by one-way ANOVA with multiple comparisons. The fmax and Dmin were correlated to the corresponding nCBV and ADC using partial correlation analysis, respectively. Results: Using a mono-exponential fitting of diffusion signal decay, the mean ADCmin was significantly lower in PCNSL than in glioblastoma and metastasis. However, using a bi-exponential fitting, the mean Dmin did not significantly differ in the three groups. The mean fmax significantly increased in the glioblastomas (reader 1, 0.103; reader 2, 0.109) and the metastasis (reader 1, 0.105; reader 2, 0.107), compared to the primary CNS lymphomas (reader 1, 0.025; reader 2, 0.023) (P < .001 for each). The correlation between fmax and the corresponding nCBV was highest in glioblastoma group, and the correlation between Dmin and the corresponding ADC was highest in primary CNS lymphomas group. Conclusion: Unlike ADC value derived from a mono-exponential fitting of diffusion signal, diffusion-related parametric value derived from a bi-exponential fitting with separation of perfusion effect doesn’t differ among glioblastoma, metastasis, and PCNSL. [ABSTRACT FROM AUTHOR]- Published
- 2015
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