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Herrmann CJJ, Els A, Boehmert L, Periquito J, Eigentler TW, Millward JM, Waiczies S, Kuchling J, Paul F, Niendorf T. Simultaneous T 2 and T 2 ∗ mapping of multiple sclerosis lesions with radial RARE-EPI. Magn Reson Med 2021; 86:1383-1402. [PMID: 33951214 DOI: 10.1002/mrm.28811] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2020] [Revised: 03/26/2021] [Accepted: 03/26/2021] [Indexed: 12/26/2022]
Abstract
PURPOSE The characteristic MRI features of multiple sclerosis (MS) lesions make it conceptually appealing to pursue parametric mapping techniques that support simultaneous generation of quantitative maps of 2 or more MR contrast mechanisms. We present a modular rapid acquisition with relaxation enhancement (RARE)-EPI hybrid that facilitates simultaneous T2 and T 2 ∗ mapping (2in1-RARE-EPI). METHODS In 2in1-RARE-EPI the first echoes in the echo train are acquired with a RARE module, later echoes are acquired with an EPI module. To define the fraction of echoes covered by the RARE and EPI module, an error analysis of T2 and T 2 ∗ was conducted with Monte Carlo simulations. Radial k-space (under)sampling was implemented for acceleration (R = 2). The feasibility of 2in1-RARE-EPI for simultaneous T2 and T 2 ∗ mapping was examined in a phantom study mimicking T2 and T 2 ∗ relaxation times of the brain. For validation, 2in1-RARE-EPI was benchmarked versus multi spin-echo (MSE) and multi gradient-echo (MGRE) techniques. The clinical applicability of 2in1-RARE-EPI was demonstrated in healthy subjects and MS patients. RESULTS There was a good agreement between T2 / T 2 ∗ values derived from 2in1-RARE-EPI and T2 / T 2 ∗ reference values obtained from MSE and MGRE in both phantoms and healthy subjects. In patients, MS lesions in T2 and T 2 ∗ maps deduced from 2in1-RARE-EPI could be just as clearly delineated as in reference maps calculated from MSE/MGRE. CONCLUSION This work demonstrates the feasibility of radially (under)sampled 2in1-RARE-EPI for simultaneous T2 and T 2 ∗ mapping in MS patients.
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Affiliation(s)
- Carl J J Herrmann
- Berlin Ultrahigh Field Facility (B.U.F.F.), Max Delbrück Center for Molecular Medicine in the Helmholtz Association, Berlin, Germany.,Department of Physics, Humboldt University of Berlin, Berlin, Germany
| | - Antje Els
- Berlin Ultrahigh Field Facility (B.U.F.F.), Max Delbrück Center for Molecular Medicine in the Helmholtz Association, Berlin, Germany
| | - Laura Boehmert
- Berlin Ultrahigh Field Facility (B.U.F.F.), Max Delbrück Center for Molecular Medicine in the Helmholtz Association, Berlin, Germany
| | - Joao Periquito
- Berlin Ultrahigh Field Facility (B.U.F.F.), Max Delbrück Center for Molecular Medicine in the Helmholtz Association, Berlin, Germany
| | - Thomas Wilhelm Eigentler
- Berlin Ultrahigh Field Facility (B.U.F.F.), Max Delbrück Center for Molecular Medicine in the Helmholtz Association, Berlin, Germany.,Chair of Medical Engineering, Technical University of Berlin, Berlin, Germany
| | - Jason M Millward
- Berlin Ultrahigh Field Facility (B.U.F.F.), Max Delbrück Center for Molecular Medicine in the Helmholtz Association, Berlin, Germany
| | - Sonia Waiczies
- Berlin Ultrahigh Field Facility (B.U.F.F.), Max Delbrück Center for Molecular Medicine in the Helmholtz Association, Berlin, Germany
| | - Joseph Kuchling
- Experimental and Clinical Research Center, a joint cooperation between the Charité Medical Faculty and the Max Delbrück Center for Molecular Medicine, Berlin, Germany.,NeuroCure Clinical Research Center, Charité-Universitätsmedizin, Berlin, Germany.,Department of Neurology, Charité-Universitätsmedizin, Berlin, Germany
| | - Friedemann Paul
- Experimental and Clinical Research Center, a joint cooperation between the Charité Medical Faculty and the Max Delbrück Center for Molecular Medicine, Berlin, Germany.,NeuroCure Clinical Research Center, Charité-Universitätsmedizin, Berlin, Germany.,Department of Neurology, Charité-Universitätsmedizin, Berlin, Germany
| | - Thoralf Niendorf
- Berlin Ultrahigh Field Facility (B.U.F.F.), Max Delbrück Center for Molecular Medicine in the Helmholtz Association, Berlin, Germany.,Experimental and Clinical Research Center, a joint cooperation between the Charité Medical Faculty and the Max Delbrück Center for Molecular Medicine, Berlin, Germany
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Menon RG, Walsh EG, Twieg DB, Cantrell CG, Vakil P, Jonathan SV, Batjer HH, Carroll TJ. Snapshot MR technique to measure OEF using rapid frequency mapping. J Cereb Blood Flow Metab 2014; 34:1111-6. [PMID: 24756077 PMCID: PMC4083374 DOI: 10.1038/jcbfm.2014.59] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/17/2013] [Accepted: 03/12/2014] [Indexed: 11/09/2022]
Abstract
Magnetic resonance (MR)-based oxygen extraction fraction (OEF) measurement techniques that use blood oxygen level-dependent (BOLD)-based approaches require the measurement of the R2' decay rate and deoxygenated blood volume to derive the local oxygen saturation in vivo. We describe here a novel approach to measure OEF using rapid local frequency mapping. By modeling the MR decay process in the static dephasing regime as two separate dissipative and oscillatory effects, we calculate the OEF from local frequencies measured across the brain by assuming that the biophysical mechanisms causing OEF-related frequency changes can be determined from the oscillatory effects. The Parameter Assessment by Retrieval from Signal Encoding (PARSE) technique was used to acquire the local frequency change maps. The PARSE images were taken on 11 normal volunteers, and 1 patient exhibiting hemodynamic stress. The mean MR-OEF in 11 normal subjects was 36.66±7.82%, in agreement with positron emission tomography (PET) literature. In regions of hemodynamic stress induced by vascular steal, OEF exhibits the predicted focal increases. These preliminary results show that it is possible to measure OEF using a rapid frequency mapping technique. Such a technique has numerous advantages including speed of acquisition, is noninvasive, and has sufficient spatial and temporal resolution.
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Affiliation(s)
- Rajiv G Menon
- Department of Radiology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, USA
| | - Edward G Walsh
- Department of Neuroscience, Brown University, Providence, Rhode Island, USA
| | - Donald B Twieg
- Deparment of Biomedical Engineering, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Charles G Cantrell
- Department of Radiology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, USA
| | - Parmede Vakil
- Department of Radiology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, USA
| | - Sumeeth V Jonathan
- Department of Radiology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, USA
| | - Hunt H Batjer
- Department of Neurosurgery, UT Southwestern, Dallas, Texas, USA
| | - Timothy J Carroll
- 1] Department of Radiology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, USA [2] Department of Biomedical Engineering, Northwestern University, Chicago, IL, USA
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