MRI Findings in Tumefactive Demyelinating Lesions: A Systematic Review and Meta-Analysis

Abstract

Conventional MR imaging findings may help differentiate tumefactive demyelinating lesions from primary brain tumor, though further study is needed to determine the added value of advanced MR imaging.

Magnetic resonance imaging diagnosis of demyelinating diseases: An update

“…22,59 Cases of tumefactive lesions in patients receiving disease-modifying drugs have also been reported. 64 Tumefactive demyelinating lesions can be differentiated from tumors, such as glioblastoma or lymphoma, by the following points: (i) tumefactive lesions have less mass effect compared with tumors; 57 (ii) surrounding enhancement of tumefactive lesions is often discontinuous (open-ring sign); 64,65 (iii) a T2-hypointense rim is seen in approximately half of tumefactive lesions; 66 (iv) perilesional edema is mild or absent in 57% of tumefactive lesions; 66 (v) relative cerebral blood volume on perfusion MRI is lower in tumefactive lesions than tumors; 67 (vi) density on non-contrast-enhanced computed tomography of MRI enhancing portions is lower in tumefactive lesions than in tumors; 68 (vii) intralesional susceptibility signals (dot-like hypointensities) are not seen in tumefactive lesions, although these signals are almost always seen in glioblastomas; 69 and (viii) a dilated vein coursing within the lesion might be seen. 64 Tumefactive demyelinating lesions can be differentiated from tumors, such as glioblastoma or lymphoma, by the following points: (i) tumefactive lesions have less mass effect compared with tumors; 57 (ii) surrounding enhancement of tumefactive lesions is often discontinuous (open-ring sign); 64,65 (iii) a T2-hypointense rim is seen in approximately half of tumefactive lesions; 66 (iv) perilesional edema is mild or absent in 57% of tumefactive lesions; 66 (v) relative cerebral blood volume on perfusion MRI is lower in tumefactive lesions than tumors; 67 (vi) density on non-contrast-enhanced computed tomography of MRI enhancing portions is lower in tumefactive lesions than in tumors; 68 (vii) intralesional susceptibility signals (dot-like hypointensities) are not seen in tumefactive lesions, although these signals are almost always seen in glioblastomas; 69 and (viii) a dilated vein coursing within the lesion might be seen.…”

“…[60][61][62][63] A variety of gadolinium-enhancing patterns, such as homogeneous, heterogeneous, patchy and diffuse, open-ring, and irregular rim, are seen according to different pathologies. 64 Tumefactive demyelinating lesions can be differentiated from tumors, such as glioblastoma or lymphoma, by the following points: (i) tumefactive lesions have less mass effect compared with tumors; 57 (ii) surrounding enhancement of tumefactive lesions is often discontinuous (open-ring sign); 64,65 (iii) a T2-hypointense rim is seen in approximately half of tumefactive lesions; 66 (iv) perilesional edema is mild or absent in 57% of tumefactive lesions; 66 (v) relative cerebral blood volume on perfusion MRI is lower in tumefactive lesions than tumors; 67 (vi) density on non-contrast-enhanced computed tomography of MRI enhancing portions is lower in tumefactive lesions than in tumors; 68 (vii) intralesional susceptibility signals (dot-like hypointensities) are not seen in tumefactive lesions, although these signals are almost always seen in glioblastomas; 69 and (viii) a dilated vein coursing within the lesion might be seen. 70,71 Tumefactive lesions usually diminish on follow-up MRI, in contrast to continual enlargement seen in real tumors.…”

Differential Diagnosis of Intracranial Masses

“…Instead, a trial of immune-modulating therapy should be given. Features suggesting a TDL (instead of a neoplasm) include: lesion centered in white-matter (including corpus callosum); central-vein sign; "garland-like" or incomplete rim-enhancement ("open ring" or "horseshoe"); less than expected volume effect; rCBV lower than neoplasm; ADC values higher than neoplasm (GBM or lymphoma); and non-contrast CT showing low attenuation (compared to solid portions of GBM and hyper-attenuation of lymphoma [2][3][4] (Fig. 8.3).…”

“…Schwannomas arise from the peripheral portions of the cranial nerves [3][4][5][6][7][8][9][10][11][12]-so they are ventral to the brainstem, most commonly in the posterior fossa. The most common site of origin is the inferior division of the vestibular nerve, at the apex of the internal auditory canal (IAC)-VS (vestibular Schwannoma).…”

Don’t Judge a Book by Its Cover: A Clinical Neuropathological Conference Case

“…Among those MR imaging characteristics, one of the highly specific MR imaging features according to a meta-analysis and systemic review by Suh et al was an open ring or incomplete rim enhancement that favored TDL over primary brain tumor like GBM. 12 TDL overall has less cerebral blood volume compared to brain neoplasms. [13][14][15] Another striking feature to distinguish TDLs from GBM is the regions of hypo-attenuation on non-contrast CT which were previously enhanced on MR imaging seen in TDLS while calcification or hemorrhage seen more with GBM.…”