Rationale And Objective: To evaluate the vascularity and vascular leakage of well-enhanced gliomas by double-echo dynamic magnetic resonance (MR) imaging.
Materials And Methods: Eight patients with glioblastoma multiforme (GBM) and two patients with juvenile pilocytic astrocytoma (JPA) were studied. Double-echo dynamic MR imaging was utilized to separate the T2* shortening effect and the T1 shortening effect. The former was represented by the vascularity index, and the latter was represented by the leakage index. These indexes were compared with histopathologic data.
Results: The mean vascularity index of the GBM was higher than that of the JPA (mean +/- SD, 3.48 +/- 1.57 [GBM] versus 0.51 +/- 0.29 [JPA]), and the mean leakage index of the JPA was higher than that of the GBM (1.35 +/- 0.87 [JPA] versus 0.27 +/- 0.15 [GBM]). Abundant vascularity was noted in the tight interstitial space in the pathologic specimen of GBM. Conversely, sparse vasculature was observed in the wide interstitial space in the pathologic specimen of JPA.
Conclusion: This method may enable better characterization of grade in well-enhanced glioma by providing the information on the vascularity and leakage indexes.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1097/00004424-200210000-00006 | DOI Listing |
AJNR Am J Neuroradiol
November 2024
From the Department of Radiology and Imaging, Hospital for Special Surgery, New York, NY, USA (Y.L., E.T.T., S.T., D.B.S.), Department of Medical Imaging and Intervention, Chang Gung Memorial Hospital, Taoyuan, Taiwan (Y.L.), Tesla Dynamic Coils, Zaltbommel, The Netherlands (M.L.) and Division of Plastic and Reconstructive Surgery, Weill Cornell Medicine, New York, USA (L.G.).
This technical report describes use of a novel, conformable receive-only radiofrequency coil for 3T magnetic resonance (MR) neurography in a cohort of patients with occipital neuralgia. Applying a sub-millimeter, isotropic three-dimensional double-echo steady-state sequence, detailed visualization of the occipital nerves and associated pathologies could be achieved.ABBREVIATIONS: ABC= definition; XYZ= definition.
View Article and Find Full Text PDFJ Magn Reson
July 2023
Zavoisky Physical-Technical Institute FRC Kazan Scientific Center of RAS, Sibirsky Tract 10/7, Kazan 420029, Russia. Electronic address:
Methods of multi-pulse sequences are widely used in magnetic resonance to study the local properties of magnetic particles and to increase the lifetime of spin coherence. Imperfect refocusing pulses lead to non-exponential signal decay due to the contribution of the coherence pathways in which T and T relaxation segments are mixed. Here, we present analytical approximations for echoes generated in the Carr-Purcell-Meiboom-Gill (CPMG) sequence.
View Article and Find Full Text PDFMagn Reson Med
June 2020
High-Field MR Center, Department of Biomedical Imaging and Image-guided Therapy, Medical University of Vienna, Vienna, Austria.
Purpose: In this study, we demonstrate the first combination of 3D FID proton MRSI and spatial encoding via concentric-ring trajectories (CRTs) at 3T. FID-MRSI has many benefits including high detection sensitivity, in particular for J-coupled metabolites (e.g.
View Article and Find Full Text PDFMagn Reson Med
August 2019
High Field MR Center, Department of Biomedical Imaging and Image-Guided Therapy, Medical University Vienna, Vienna, Austria.
Purpose: To assess the performance, in the presence of scanner instabilities, of three dynamic correction methods which integrate ∆B mapping into the chemical exchange saturation transfer (CEST) measurement and three established static ∆B -correction approaches.
Methods: A homogeneous phantom and five healthy volunteers were scanned with a CEST sequence at 7 T. The in vivo measurements were performed twice: first with unaltered system frequency and again applying frequency shifts during the CEST acquisition.
NMR Biomed
March 2018
Department of Radiology, Tri-Service General Hospital, Taipei, Taiwan, Republic of China.
The aim of this study was to investigate proton changes of the parotid gland after gustatory stimulation by semi-quantitative parameters and an empirical mathematical model (EMM) using high-temporal-resolution, double-echo, echo-planar imaging (EPI). Approved by a local institutional review board, this study examined 20 parotid glands from 10 healthy volunteers (male:female = 6: 4; age ± standard deviation =35.1 ± 14.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!