The MRI Appearance of Tumefactive Demyelinating Lesions

Abstract

Pictorial Essay D Fig. 1.-21-year-old woman presenting with new-onset seizure and biopsy-proven tumefactive demyelinating lesion. A, Enhanced axial T1-weighted spin-echo image reveals large left frontal lesion with incomplete ring of enhancement (arrow), open on gray matter side of lesion. There is faint enhancement within dilated, centrally located venous structures (arrowhead), suggestive of demyelinating lesion. B, Enhanced coronal T1-weighted spin-echo image reveals large left frontal lesion with incomplete ring of enhancement (arrow). C, Unenhanced axial T2-weighted spin-echo image reveals relatively little mass effect or surrounding vasogenic edema given size of lesion.

Utility of Proton MR Spectroscopy for Differentiating Typical and Atypical Primary Central Nervous System Lymphomas from Tumefactive Demyelinating Lesions

“…PCNSLs tend to have a low ADC value because of high cellularity, whereas TDLs are usually associated with elevated ADC values. 10,19 However, at times, an acute demyelinating lesion may also have areas of low ADC values, which makes it difficult to differentiate from tumors. 20 Cha et al 21,22 summarized the perfusion MR imaging features of brain tumors.…”

“…When such lesions appear as solitary masses Ͼ2 cm in the longest diameter, they are defined as tumefactive demyelinating lesions (TDLs), and they can cause symptoms mimicking brain neoplasms and can be associated with variable enhancement on MR imaging. 10 Differentiation between PCNSLs and TDLs by use of conventional MR can sometimes be challenging, especially when there are atypical MR imaging features in PCNSLs. Considering the rapid progress of PCNSLs, early differentiation is important because both the treatment effectiveness and the patient survival rate will substantially decrease if there is delayed radiation therapy and/or chemotherapy.…”

Dynamic perfusion CT in brain tumors

“…Tumefactive demyelinating lesions (TDLs) are solitary lesions greater than 2 cm that mimic HGGs on contrast-enhanced MR images [25], and can also be confused with HGGs on histopathology [26]. Differentiation of TDLs from HGGs may avoid unnecessary biopsy and resection of viable brain tissue.…”

Differentiation of Tumefactive Demyelinating Lesions from High-Grade Gliomas with the Use of Diffusion Tensor Imaging

“…1 A TDL misdiagnosed as a neoplasm could lead to unnecessary surgical intervention or even radiation therapy, which could exacerbate demyelinating diseases. 2 Certain conventional MR imaging features, including a relative lack of mass effect, less substantial perifocal edema, and an open ring of enhancement, 1,3,4 which were previously thought to be characteristics of TDLs, were considered to be nonspecific in a more recent study reviewing the conventional MR imaging findings of 168 patients with biopsy-confirmed TDLs. 5 TDLs can also be confused with high-grade gliomas on histopathologic evaluation because of the presence of hypercellularity and atypical reactive astrocytes with mitotic figures.…”