Article

Imaging of Brain Tumors: MR Spectroscopy and Metabolic Imaging

Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, 600 North Wolfe Street, Baltimore, MD 21287, USA.
Neuroimaging Clinics of North America (Impact Factor: 1.53). 08/2010; 20(3):293-310. DOI: 10.1016/j.nic.2010.04.003
Source: PubMed

ABSTRACT

The utility of magnetic resonance spectroscopy (MRS) in diagnosis and evaluation of treatment response to human brain tumors has been widely documented. The role of MRS in tumor classification, tumors versus nonneoplastic lesions, prediction of survival, treatment planning, monitoring of therapy, and post-therapy evaluation is discussed. This article delineates the need for standardization and further study in order for MRS to become widely used as a routine clinical tool.

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    • "Both PET and MRS have been used clinically for evaluating tumor metabolism. Although MRS is capable of detecting metabolic dysfunction in tissue that otherwise appears normal on structural imaging, most clinical applications are limited to a small region with single-voxel or multi-voxel acquisitions due to long acquisition time or SNR limitations [10]. In contrast, 18 F-FDG-PET can quickly outline potential metabolic abnormalities throughout the body, but may yield false positive results associated with inflammation, etc. "
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    • "In a follow-up survey we performed six years after the conduction of the original work so to provide a more thorough knowledge of any changes in practice patterns by hospitals to keep up with field advancements, we found that MRS was started to become a standard service in most hospitals. This finding conformed to some extent with observations by contemporary works expressing the beginning of its acceptance, though not universally , as routine clinical procedure [39]. On the contrary, fMRI was still unrecognized as it was during the initial earlier survey. "
    [Show abstract] [Hide abstract] ABSTRACT: Functional magnetic resonance imaging “fMRI” and magnetic resonance spectroscopy “MRS” are two crucial milestones that were introduced apart from one another into brain imaging and their implementation in major local cities is eventual step. Thus, the purpose of this study was to compare those techniques in terms of their clinical utilization in patient care delivery among the major governmental and private hospitals within Jeddah city. The study initially included eighteen hospitals to identify whether they were utilizing fMRI and MRS in their clinical practice. Out of the 18 hospitals under study only one hospital (5.6%) had both fMRI and MRS software; 7 (38.9%) had MRS but not fMRI; 4 (22.2%) did not have fMRI or MRS; and 6 (33.3%) hospitals had no MRI machine at all. Out of the eight hospitals applying MRS with one being excluded, the starting date of application was 2002 in 4 (57.1%) hospitals, 2004 in 1 (14.3%) hospital, and 2006 in 2 (28.6%) hospitals. The frequency of doing MRS was once a week in 2 (28.6%) hospitals, 2-3 cases/week in 3 (42.9%) hospitals, 5-10 cases/week in 1 (14.3%) hospital, and once every 6 months in 1 (14.3%) hospital. On the other hand, fMRI was applied only by one hospital starting in 2000 and was soon dismissed due to its time consumption and the inability of patients to accurately follow given instructions. It was concluded that MRS was more widely utilized compared to fMRI. Later on, a follow-up survey in the year of 2014 demonstrated that MRS has started to become a standard service in most hospitals whereas fMRI was still being unrecognized.
    Full-text · Article · Sep 2015 · Open Journal of Medical Imaging
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    • "Additional metabolites of interest include lipid and lactate peaks at approximately 1.3 ppm and myo-inositol at approximately 3.5 ppm. Lipids and lactate are considered markers of necrosis and hy-poxia, respectively, and myo-inositol is considered to be related to astrocytic integrity and regulation of brain osmosis131132133134. The MRS profile of gliomas is generally considered elevated Cho and decreased NAA135136137 . "
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