TY - JOUR
T1 - Mr imaging of extracranial nerve sheath tumors
AU - Varma, Datla G.K.
AU - Moulopoulos, Angela
AU - Sara, Alan S.
AU - Leeds, Norman
AU - Kumar, Rajendra
AU - Kim, E. Edmund
AU - Wallace, Sidney
N1 - Copyright:
Copyright 2017 Elsevier B.V., All rights reserved.
PY - 1992
Y1 - 1992
N2 - We retrospectively reviewed MR images of 32 histologically proven extracranial nerve sheath tumors (NSTs). There were 23 benign (10 neurofibromas, 13 schwannomas) and 9 malignant NSTs. On Tl-weighted images (TlWIs) tumors were isointense or slightly hyperintense to muscle. On T2-weighted images (T2WIs) (11 lesions) and enhanced TlWIs (1 intraspinal lesion), a target pattern with peripheral hyperintense rim and central low intensity was seen in 12 of 23 (52%) benign NSTs (5 of 10 neurofibromas and 7 of 13 schwannomas). This pattern corresponded histologically to peripheral myxomatous tissue and central fibrocollagenous tissue. The pattern was absent in lesions with cystic, hemorrhagic, or necrotic degeneration. These tumors were hyperintense and variably inhomogeneous on T2WIs. Malignant NSTs were hyperintense and variably inhomogeneous on T2WIs and mimicked benign variably inhomogeneous lesions unless involvement of contiguous structures was visualized. A target pattern was not visible in malignant lesions. Magnetic resonance imaging cannot distinguish schwannomas from neurofibromas, and benign tumors may mimic malignant NSTs when cystic, hemorrhagic, and necrotic degeneration is present. A target pattern may be visualized in some benign NSTs, and evaluation of this sign with assessment of location and growth along nerves may help to avoid confusion with other lesions.
AB - We retrospectively reviewed MR images of 32 histologically proven extracranial nerve sheath tumors (NSTs). There were 23 benign (10 neurofibromas, 13 schwannomas) and 9 malignant NSTs. On Tl-weighted images (TlWIs) tumors were isointense or slightly hyperintense to muscle. On T2-weighted images (T2WIs) (11 lesions) and enhanced TlWIs (1 intraspinal lesion), a target pattern with peripheral hyperintense rim and central low intensity was seen in 12 of 23 (52%) benign NSTs (5 of 10 neurofibromas and 7 of 13 schwannomas). This pattern corresponded histologically to peripheral myxomatous tissue and central fibrocollagenous tissue. The pattern was absent in lesions with cystic, hemorrhagic, or necrotic degeneration. These tumors were hyperintense and variably inhomogeneous on T2WIs. Malignant NSTs were hyperintense and variably inhomogeneous on T2WIs and mimicked benign variably inhomogeneous lesions unless involvement of contiguous structures was visualized. A target pattern was not visible in malignant lesions. Magnetic resonance imaging cannot distinguish schwannomas from neurofibromas, and benign tumors may mimic malignant NSTs when cystic, hemorrhagic, and necrotic degeneration is present. A target pattern may be visualized in some benign NSTs, and evaluation of this sign with assessment of location and growth along nerves may help to avoid confusion with other lesions.
KW - Neoplasms-Magnetic resonance imaging
KW - Neurofibroma-Schwannoma-Nerves
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U2 - 10.1097/00004728-199205000-00020
DO - 10.1097/00004728-199205000-00020
M3 - Article
C2 - 1317391
AN - SCOPUS:0026720416
SN - 0363-8715
VL - 16
SP - 448
EP - 453
JO - Journal of computer assisted tomography
JF - Journal of computer assisted tomography
IS - 3
ER -