{"id":207,"date":"2002-10-17T15:55:52","date_gmt":"2002-10-17T20:55:52","guid":{"rendered":"http:\/\/blogs.law.harvard.edu\/neurovista\/2002\/10\/17\/mr-spectroscopy-for-glioma\/"},"modified":"2002-10-17T15:55:52","modified_gmt":"2002-10-17T20:55:52","slug":"mr-spectroscopy-for-glioma","status":"publish","type":"post","link":"https:\/\/archive.blogs.harvard.edu\/neurovista\/2002\/10\/17\/mr-spectroscopy-for-glioma\/","title":{"rendered":"MR Spectroscopy for Glioma"},"content":{"rendered":"<p>From the Literature <a href=\"http:\/\/www.thejns-net.org\">Journal of Neurosurgery<\/a> 97: 794, October 2002 Issue. <\/p>\n<p><strong>Histopathological validation of a three-dimensional magnetic resonance spectroscopy index as a predictor of tumor presence.<\/strong> <\/p>\n<p>Mcknight et al. from the Departments of Radiology, Neurosurgery, and Radiation Oncology at UCSF.<\/p>\n<p>In this article the authors examined the queston of whether the choline-NAA index (CNI)&nbsp;determined on MR spectroscopy&nbsp;could be used to detect metabolically active tumor in T2 hyperintense yet non-enhancing regions&nbsp;in patients with intrinsic brain tumors. &nbsp;<\/p>\n<p>The authors first used histologic criteria to generate a proposed cut-off for CNI to predict tumor versus non-tumorous tissue.&nbsp; They found that in non-tumorous biopsies that the CNI was 1.7 while in Grade II, Grade III and Grade IV astrocytoma, this ratio was over 5.3. Using a CNI of 2.5, tumor could be distinguished from non-tumorous tissue with 90% specificity and 86% specificity. <\/p>\n<p>Using this index, the authors then examined what percentage of MR defined lesion by T2 or T1 with constrast had a CNI greater than 2.5.&nbsp; More than 1\/3 of cases had CNI values consistent with tumor in the T2 intense region surrounding the contrast enhanced zone. <\/p>\n<p>The authors also assessed heterogeneity of the CNI in the T2 hyperintense regions yet nonenhancing regions of Grade II, III, and IV astrocytomas.&nbsp; In each of these grade tumors, &gt;40% of the total T2 hyperintense, non enhancing volume had a CNI greater than 2.5.&nbsp; <\/p>\n<p>&nbsp;<\/p>\n<p><strong>Commentary<\/strong>: The non-invasive detection of metabolically active tumor continues to be actively pursued as these authors describe.&nbsp; One important implication of the current study is that it may be possible to target the most metabolically active regions of non-enhancing tumors as defined by a CNI ratio of &gt;2.5.&nbsp; These so called &#8220;MR defined hotspots&#8221; may be useful to improve the diagnostic yield in the biopsy of non-enhancing lesions.&nbsp; ~Bob Carter, M.D., ~Fred Barker, M.D.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>From the Literature Journal of Neurosurgery 97: 794, October 2002 Issue. Histopathological validation of a three-dimensional magnetic resonance spectroscopy index as a predictor of tumor presence. Mcknight et al. from the Departments of Radiology, Neurosurgery, and Radiation Oncology at UCSF. In this article the authors examined the queston of whether the choline-NAA index (CNI)&nbsp;determined on [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[],"tags":[],"class_list":["post-207","post","type-post","status-publish","format-standard","hentry"],"jetpack_featured_media_url":"","_links":{"self":[{"href":"https:\/\/archive.blogs.harvard.edu\/neurovista\/wp-json\/wp\/v2\/posts\/207","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/archive.blogs.harvard.edu\/neurovista\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/archive.blogs.harvard.edu\/neurovista\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/archive.blogs.harvard.edu\/neurovista\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/archive.blogs.harvard.edu\/neurovista\/wp-json\/wp\/v2\/comments?post=207"}],"version-history":[{"count":0,"href":"https:\/\/archive.blogs.harvard.edu\/neurovista\/wp-json\/wp\/v2\/posts\/207\/revisions"}],"wp:attachment":[{"href":"https:\/\/archive.blogs.harvard.edu\/neurovista\/wp-json\/wp\/v2\/media?parent=207"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/archive.blogs.harvard.edu\/neurovista\/wp-json\/wp\/v2\/categories?post=207"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/archive.blogs.harvard.edu\/neurovista\/wp-json\/wp\/v2\/tags?post=207"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}