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- Askaner, Krister, et al.
(författare)
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Differentiation of Brain Metastases due to Primary Malignancy and Glioblastomas using Dynamic Susceptibility Contrast-Enhanced MR at 3T
- 2017
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Konferensbidrag (refereegranskat)abstract
- Purpose:To find out differences in cerebral blood volume (CBV) maps derived from dynamic susceptibility contrast-enhanced magnetic resonance imaging (DSCE-MRI) in glioblastomas and cerebral metastases. The main purpose was to compare CBV maps between metastases with different primary malignancies. Furthermore the metastasis group was compared with the glioblastoma group.Method:Conventional imaging and DSCE-MRI using 3T MRI system was performed in 114 patients, 38 glioblastomas and 76 metastases, 32 lung, 12 breast, 12 melanoma, 10 gastrointestinal (GI), and 10 other. CBV values were measured in the solid tumor area, peritumoral edema, area adjacent to peritumoral edema, and in normal apparent white matter in contralateral semioval center. The four subgroups of metastases were compared with one-way ANOVA to determine differences in CBV of significance. CBV values in glioblastomas and metastases were then statistically compared using paired t-test. Receiver -operating characteristic analysis was used to determine optimal cut-off values when parameters showed statistical differences.Results:There were no significantly differences in CBV between the four subgroups of metastases. CBV in the peritumoral edema significantly differentiated metastases from glioblastomas, p=0.0001. CBV cutoff value of 2.3 yielded a sensitivity, specificity, positive predictive value, and negative predictive value of 87, 87, 71, and 91% respectively. Conclusions:Differentiation of glioblastomas and metastases is possible using DSCE-MRI. No statistically significant differences regarding CBV between metastases from lung, breast, melanoma, and GI were detected.
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| 2. |
- Follin, Cecilia, et al.
(författare)
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Hypothalamic dysfunction revealed by magnetic resonance diffusion tensor imaging in childhood leukemia survivors treated with cranial radiotherapy but not in craniopharyngeoma survivors
- 2016
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Konferensbidrag (refereegranskat)abstract
- Background: Metabolic complications with obesity are frequent in childhood acute lymphoblastic leukemia (ALL) survivors treated with cranial radiotherapy (CRT). Childhood onset Craniopharyngioma (CP) survivors without hypothalamic (HT) involvement are spared gross obesity. Magnetic resonance diffusion tensor imaging (DTI) provides information of microstructure function of the brain and quantified as fractional anisotrophy (FA), mean diffusivity (MD), axial and radial diffusivity (AD, RD). Since MD in HT is reportedly impaired (increased) in obese compared to non-obese subjects, we investigated DTI in the HT.Methods: Twenty nine ALL survivors on hormone supplementation were investigated 34 years after CRT (24 Gy). 17 CO-CP survivors with hormone supplementation but without HT damage were investigated. Comparisons were made with these two patient populations to 27 matched controls regarding DTI parameters in the HT and for BMI, fat mass, fat free mass and waist/hip measurements.Results: We recorded reduced FA (0.27 vs 0.29, P=0.04), and increased MD (1.13 vs 1.00, P<0.001), AD (1.41 vs 1.25, P<0.001), and RD (0.99 vs 0.86, P<0.001) in the right HT and increased MD (1.42 vs 1.25, P<0.001), AD (1.75 vs 1.58, P<0.001), and RD (1.25 vs 1.04, P<0.001) in left HT in ALL survivors compared to matched controls. The CPs showed no difference in the HT for these parameters compared to controls. ALL survivors with a BMI ≥ 25 showed elevated MD (P=0.03) and AD (P=0.02) compared to ALL survivors with a BMI < 25 and compared to controls with BMI ≥ 25 in the right HT. This was not the case in CP survivors or in controls.Conclusions: Thirty four years after CRT for ALL, DTI measures are deranged in the HT. ALL survivors with a BMI ≥ 25 were presented with worse HT dysfunction. CP survivors were unaffected. The present data suggests changes in the microstructure of the HT in these ALL survivors.
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| 4. |
- Olsson, Hampus, et al.
(författare)
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Magnetization transfer (MT) of human brain at 7T in the context of a 3D multi-parameter mapping protocol
- 2019
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Ingår i: Magnetization transfer (MT) of human brain at 7T in the context of a 3D multi-parameter mapping protocol. - 1545-4428. ; 27
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Konferensbidrag (refereegranskat)abstract
- 3D multi-gradient echo MRI can be used to estimate T1, T2*, PD and the magnetization transfer (MT), which is increasingly used for multi-parametricmapping (MPM) of human brain. The increased polarization at 7T compared to lower B0 allows for increased spatial resolution or reduced scantimes. However, SAR restrictions imposed on the MT pulse and B1 inhomogeneity pose challenges. In this work, we propose a protocol for MPM ofhuman brain at 7T with special attention paid to eliminating bias when mapping MT saturation while obtaining sub-millimeter isotropic spatial resolution inunder 12 minutes with acceptable SNR.
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