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1.
This study evaluates the effectiveness of CT and MR imaging in differentiating intradural extramedullary spinal schwannomas and meningiomas in a large group of patients. In addition, the study correlates tumour location, morphologic characteristics and enhancement pattern. From January 2000 to June 2007, we retrospectively reviewed 128 consecutive patients (51 male, 77 female; mean age at admission 53.8 years; range 17–83 years) with spinal intradural extramedullary tumours (92 schwannomas, 36 meningiomas) at our institution. Fifty-one of ninety-two schwannomas (55.4%) showed fluid signal intensity on T2-weighted MR images. Twenty-two of thirty-six meningiomas (61.1%) showed hyperintense signal intensity and thirteen of thirty-six meningiomas (36.1%) showed isointense signal on T2-weighted MR images. Fifty-four schwannomas (58.7%) showed rim enhancement and thirty-three meningiomas (91.7%) showed diffuse enhancement on contrast-enhanced T1-weighted MR imaging. Twenty-one meningiomas (58.3%) showed dural tail sign in contrast-enhanced T1-weighted MR imaging. Twenty-one meningiomas (58.3%) showed calcification on CT images. MR and CT imaging results are therefore useful for the differentiation of schwannomas from meningiomas of the spine.  相似文献   

2.
Summary Magnetic resonance (MR) images of 29 consecutive patients with intraspinal neoplasms (9 intramedullary tumors, 20 extramedullary tumors) were reviewed to evaluated the utility of MR imaging in distinguishing the intraspinal compartmental localisation and signal characteristics of each lesion. Compartment and histology of all neoplasms were surgically proven. MR correctly assigned one of three compartments to all lesions, 9 intramedullary, 14 intradural extramedullary (6 schwannomas, 3 neurofibromas, 5 meningiomas), and 6 extradural (3 schwannomas, 1 meningioma, 1 cavernous hemangioma, 1 metastatic renal cell carcinoma). All intramedullary tumors showed swelling of the spinal cord itself. In all five extradural tumors a low intensity band was visualized between the spinal cord and tumor. On the other hand, a low intensity band was demonstrated in no cases with intradural tumors. Visualization of this low intensity band is important in differentiating extradural from intradural-extramedullary lesions. We call this low intensity band, the extradural sign. Signal intensity of intradural tumors varied with histology. In extramedullary tumors, signal intensity of schwannomas was similar to that of the cerebrospinal fluid (CSF) both on T1 weighted (inversion recovery) and T2 weighted spin echo (SE) images. On the other hand, meningiomas tended to be isointense to the spinal cord on both T1 and T2 weighted SE images. We found relatively reliable signal characteristics to discriminate meningioma from schwannoma.  相似文献   

3.
Thirty-one consecutive intradural extramedullary spinal tumors examined with MR at 0.3 T were reviewed. In 13 of the patients myelography had been performed. There were 11 patients with meningeoma, 14 with neuroma, one ependymoma, 3 metastases, and 2 lipomas. All tumors were surgically removed and verified by histology. The intradural extramedullary location of the tumors was accurately assessed by MR imaging in all patients and by myelography in 10 of 13. The MR diagnoses were in accordance with the histologic findings in 74% of cases. Compression of the spinal cord or cauda equina with widening of the subarachnoid space above and below the mass or outward displacement of epidural fat was characteristic of the intradural extramedullary tumors. The signal intensity of meningeoma as well as of neuroma was slightly lower or equal to that of the cord on T1-weighted images, and equal to or higher than cord signal on T2-weighted images. Neuroma had a lower signal intensity on T1-weighted images and a higher signal intensity on T2-weighted images than meningeoma. Meningeoma appeared more homogeneous than neuroma and had a broad base towards the dura.  相似文献   

4.
Imaging of the spine and spinal cord has traditionally been accomplished with plain radiography, myelography, and CT. Recently, MR imaging has become the technique of choice in the assessment of lesions of the spine and spinal cord. MR imaging provides accurate localization of intramedullary, intradural extramedullary, and extradural tumors. Ependymomas and low-grade astrocytomas are the most common intramedullary tumors. MR imaging findings are distinguishable by the delineation and size of the lesion, and the signal intensity on T2-weighted images. Other less common tumors include malignant astrocytomas, hemangioblastomas, and intramedullary metastasis. Numerous foci of high-velocity signal loss are seen in the hemangioblastomas. Metastasis, meningiomas, and schwannomas are the most common intradural extramedullary tumors. Meningiomas are characterized by dural enhancement on postcontrast T1-weighted images. Schwannomas and neurofibromas often erode bony structures and appear to be dumbbell-shaped. Epidural metastasis accounts for the majority of extradural tumors. Primary malignant extradural tumors include lymphomas, chordomas, and so on. The most common primary benign extradural tumor is hemangioma, which often appears to be hyperintense on both T1-weighted and T2-weighted images. Intramedullary non-neoplastic lesions include demyelinating, vascular, and infectious diseases. Diffuse, peripheral, or speckled contrast enhancement, and lack of contrast enhancement may suggest non-neoplastic lesions.  相似文献   

5.
Spinal epidural cavernous hemangioma: MR findings   总被引:6,自引:0,他引:6  
PURPOSE: Cavernous hemangiomas with a spinal epidural location are very uncommon vascular tumors in contrast to those in the vertebral body. The purpose of this study was to describe the radiologic findings, focusing on the MR studies, of spinal epidural cavernous hemangiomas. METHOD: Five pathologically proven cases of spinal epidural cavernous hemangioma were retrospectively reviewed. MR (n = 5) and CT (n = 1) were evaluated. RESULTS: The level was thoracic (n = 4) or lumbosacral (n = 1). The mass was located in the epidural space and showed paravertebral extension in all cases. It showed a lobulated contour in all cases and encircled the spinal cord partially with a larger posterior (n = 3) or anterior (n = 1) component in four cases. In all cases, the mass showed high signal intensity on T2-weighted images and homogeneous, strong enhancement. Adjacent bony erosion (n = 5) and intervertebral neural foraminal widening (n = 4) were common. CONCLUSION: Spinal epidural cavernous hemangioma shows characteristic MR findings of a lobulated contoured epidural mass partially encircling the spinal cord with a larger posterior component in the spinal canal, high signal intensity on T2-weighted images, and homogeneous, strong enhancement.  相似文献   

6.
PURPOSETo describe the MR and CT imaging features of hemangiopericytoma and to identify the characteristics that might distinguish them from meningioma.METHODSWe retrospectively reviewed the CT and MR findings in 34 pathologically proved cases of hemangiopericytoma. We evaluated the size, shape, and location of the tumor; the presence of hydrocephalus, edema, and mass effect; the type of dural attachment (broad-based or narrow-based) and bone changes (erosion, hyperostosis); and the tumor''s density, signal, and contrast-enhancement characteristics.RESULTSThirty of 34 tumors were 4 cm or more in greatest dimension, 32 were lobular, and only seven were in the posterior fossa. Hydrocephalus was present in 18, edema in 30, and mass effect in 33. Twenty-three had broad-based dural attachment and 11 had narrow-based attachment. All 26 unenhanced CT scans showed hyperdense tumors; 19 were heterogeneous and seven homogeneous. All 27 contrast-enhanced CT scans showed enhancement; 17 were heterogeneous and 10 homogeneous. Bone erosion was present in 17 of 29 hemangiopericytomas imaged with CT. None had hyperostosis or tumor calcifications. On T1-weighted MR images, 13 of 17 tumors were isointense with cortical gray matter; on T2-weighted image, 10 of 17 were isointense. All 14 tumors imaged with contrast enhanced T1-weighted MR imaging showed enhancement, and 13 of these were heterogeneous; eight of the 14 had a "dural tail" sign.CONCLUSIONIntracranial hemangiopericytomas are multilobulated, extraaxial tumors, sometimes associated with narrow-based dural attachment and bone erosion. Unlike with meningiomas, hyperostosis and intratumoral calcification are not present.  相似文献   

7.
脊柱区淋巴瘤的MRI特征   总被引:2,自引:0,他引:2  
目的 分析脊柱区淋巴瘤的MRI表现,以提高对其的认识.方法 回顾性分析经手术及穿刺病理或临床随访证实的脊柱区淋巴瘤45例,其中原发性5例,均为非霍奇金淋巴瘤(NHL);继发性4|D例,其中霍奇金淋巴瘤(HL)9例,NHL 31例(B细胞型27例,T细胞型4例).将MRI表现与临床、病理结果进行对照.结果 (1)病变部位:单部位发病者13例,多部位发病者32例.5例原发性者均为单部位发病,继发性者40例中32例为多发.(2)病变类型:骨质破坏型27例,表现为不同程度的骨质破坏,23例合并有软组织肿块,18例软组织病变的范围超过骨质破坏的范围;软组织肿块型6例,骨质破坏不明显,5例表现为椎管内外软组织肿块并经椎间孔相连,呈围椎、钻孔生长的特点;骨髓浸润型9例,表现为椎骨髓质MRI信号异常,骨皮质完整,椎旁软组织正常;脊髓浸润型3例,表现为脊髓增粗和MRI信号异常.(3)MRI表现:椎骨骨质破坏和骨髓浸润表现为T1WI低信号,T2WI低、等或高信号,压脂T2WI高信号.软组织肿块与相邻正常肌肉相比,T1WI呈均匀低信号,T2WI呈高信号.增强扫描肿块多呈轻至中度强化,坏死液化不明显.结论 脊柱区淋巴瘤多为继发性B细胞NHL,其主要表现是溶骨性骨质破坏伴较大范围的软组织肿块,肿块有经椎间孔相连围椎、钻孔生长的特点,增强扫描呈轻至中度均匀强化.  相似文献   

8.
PURPOSEOur purpose was to describe the MR imaging features in a series of spinal intramedullary gangliogliomas and to compare these findings with the MR features of intramedullary astrocytomas and ependymomas.METHODSA retrospective analysis was performed of 76 MR examinations in 27 patients with histologically proved spinal ganglioglioma; these were then compared with imaging findings in a representative sample of histologically proved spinal cord astrocytomas and ependymomas.RESULTSStatistically significant observations regarding spinal gangliogliomas included young age of the patients (mean, 12 years), long tumor length, presence of tumoral cyst, presence of bone erosion and scoliosis, absence of edema, presence of mixed signal intensity on T1-weighted images, and presence of patchy enhancement and cord surface enhancement. A trend (not statistically significant) was noted for holocord involvement and lack of magnetic susceptibility.CONCLUSIONSpinal ganglioglioma can be strongly suspected if MR images reflect the above criteria; however, the ultimate diagnosis still depends on radical resection and appropriate histopathologic investigation.  相似文献   

9.
BACKGROUND AND PURPOSE: Spinal epidural abscesses are major complications of epidural anesthesia, and their MR features have been reported. In patients receiving continuous infusion via an epidural catheter, MR findings may mimic those of spinal epidural abscess in the absence of infection. The purpose of this study was to assess the spinal MR findings associated with continuous epidural anesthesia. METHODS: Spinal MR findings in five consecutive patients receiving continuous epidural anesthesia were retrospectively evaluated. Axial and sagittal T1- and T2-weighted spin-echo and contrast-enhanced fat-suppressed T1-weighted spin-echo images were obtained. Infection was ruled out on microbiologic analysis three patients and on follow-up in two. Each lesion was evaluated for its MR signal intensity, location, extent, delineation, and enhancement pattern. In three patients, follow-up MR imaging was performed within 5-150 days, and the images were compared. RESULTS: Posterior epidural lesions were identified in all five patients. The lesions were isointense to hypointense relative to the spinal cord on T1-weighted images, isointense relative to CSF on T2-weighted images, and well enhanced on enhanced T1-weighted images. The anomalous enhancement involved two to seven vertebral bodies. In one patient, the enhanced lesion slightly compressed the spinal cord. On follow-up MR imaging, the epidural lesions decreased in two patients and did not change in one. CONCLUSION: Continuous epidural anesthesia can result in MR findings similar to those of epidural abscess, even in the absence of infection.  相似文献   

10.
ObjectiveTo characterize MR imaging features of pure mucinous carcinoma of the breast.Materials and methodsMR images obtained from 16 women (age range, 29–81; mean age, 57 years) with pure mucinous carcinoma of the breast determined at surgery were reviewed. The MR findings used were shape, margin, internal mass enhancement, kinetic curve pattern on dynamic study, signal intensity on short time inversion recovery (STIR) T2-weighted images, and non-mass-like enhancement around the main tumor. Non-mass-like enhancement was compared with the presence of extensive intraductal component (EIC) on histopathological findings.ResultsEleven tumors (69%) had lobular contour, and nine tumors (56%) had smooth margin. Eight tumors (50%) showed rim enhancement and six tumors (38%) showed heterogeneous enhancement. Fourteen tumors (88%) showed a persistent enhancing pattern on kinetic curve. Fifteen tumors exhibited homogenous strongly high signal intensity on STIR T2-weighted images. In six cases with EIC, five cases had non-mass-like enhancement around the main mass.ConclusionsMR findings such as lobular shape, rim or heterogeneous enhancement, persistent pattern on kinetic curve, and homogeneous strongly high signal intensity on STIR T2-weighted images may be useful in diagnosing pure mucinous carcinoma. Moreover, linear-ductal enhancement around main mass may indicate presence of EIC.  相似文献   

11.
PURPOSE: To describe imaging findings and their neuropathologic correlate in patients with cerebrotendinous xanthomatosis (CTX). MATERIALS AND METHODS: Computed tomographic (CT) and magnetic resonance (MR) images in 24 patients with symptoms (mean age at time of imaging, 37 years; mean disease duration, 18 years) were reviewed for site and frequency of brain, spinal cord, and Achilles tendon involvement. Two patients died, and imaging findings were compared with postmortem neuropathologic findings. RESULTS: Apart from nonspecific supratentorial atrophy and deep white matter changes, more typical hyperintense lesions were seen on T2-weighted images in the dentate nucleus (in 79% of patients), globus pallidus, substantia nigra, and inferior olive and extended into adjacent white matter as disease progressed. In these locations, lipid crystal clefts and perivascular macrophages, neuronal loss, demyelination, fibrosis, and reactive astrocytosis were found at microscopic examination. Hypointensity was sometimes found on T2-weighted images in the dentate nucleus and was related to deposition of hemosiderin and calcifications. CT depicted fewer lesions; all had low attenuation, except for the calcifications. Spinal cord MR imaging revealed increased signal intensity in the lateral and dorsal columns on T2-weighted images. Achilles tendon xanthomas displayed intermediate signal intensity on T1- and T2-weighted images. CONCLUSION: The typical pattern of MR imaging findings reflects the classic histopathologic findings and should prompt the diagnosis of CTX.  相似文献   

12.
PURPOSEOur purpose was to describe the MR findings and evolution of spinal cord abscess and to define those MR features that allow differentiation of cord infection from other intramedullary abnormalities.METHODSWe retrospectively reviewed the MR studies of all patients in whom intramedullary spinal cord abscess was proved either by blood or cerebrospinal fluid culture or by serologic examination at our institution between January 1988 and January 1996. The study group included four adults and two children, 7 to 74 years old (mean age, 38 years).RESULTSInitial MR studies showed intramedullary high signal on T2-weighted sequences with poorly defined marginal enhancement on T1-weighted images. On follow-up contrast-enhanced T1-weighted studies, the lesions had well-defined enhancing margins with central low signal intensity. After the initiation of therapy, T2 signal abnormalities decreased markedly and contrast-enhanced studies showed ring enhancement. These T1 findings resolved with treatment over serial studies in four patients. The organisms identified were Streptococcus milleria, S pyogenes, atypical mycobacteria, Mycobacterium tuberculosis, and Schistosoma mansoni (both children).CONCLUSIONA characteristic sequence of imaging findings aids in the differentiation of cord infection from other intramedullary lesions.  相似文献   

13.
MR imaging of spinal neurofibromatosis   总被引:2,自引:0,他引:2  
The MR findings in 7 patients with neurofibromatosis involving the spine were evaluated. Six patients had paraspinal tumors at multiple levels. In 4 they were bilateral. Five patients had multiple intraspinal lesions, frequently with growth through the neural foramen. In one patient paraspinal tumors were found in the lumbar sacral plexus and in another bony dysplasia and meningoceles but no tumors were disclosed. In 2 patients the lesions were associated with bilateral acoustic neuromas and multiple intracranial meningeomas. In one of these a spinal meningeoma with signal characteristics close to spinal cord was found. The other tumors had a signal that was equal to or slightly lower than the spinal cord and slightly higher than muscle on T1-weighted images. On T2-weighted images the tumors had a markedly increased signal compared to surrounding tissue. In 3 patients with tumors larger than 4 cm the signal intensity was inhomogeneous with decreased signal in the center on T2-weighted images, indicating the presence of increased fibrous tissue. Gadolinium-DTPA was given to one patient with marked increase in intensity of small tumors on T1-weighted images. The study shows that MR imaging is the modality of choice for evaluating most aspects of spinal and paraspinal neurofibromatosis.  相似文献   

14.
PURPOSETo evaluate the MR appearance of normal and pathologic states of the submandibular gland.METHODSMR images of 22 healthy subjects and 21 patients with histopathologically confirmed disorders of the submandibular gland (five pleomorphic adenomas, two hemangiomas, two malignant lymphomas, one adenoid cystic carcinoma, one squamous cell carcinoma, and 10 cases of sialadenitis) were reviewed.RESULTSAll normal submandibular glands showed higher signal intensity than surrounding muscle but lower intensity than fat on T1-weighted and T2-weighted images. Postcontrast images showed moderate enhancement of the gland. All the tumors had lower signal intensity than the normal submandibular gland on T1-weighted images and had intermediate to high (n = 8) or high (n = 3) signal intensity relative to the normal submandibular gland on T2-weighted images. Six of seven benign tumors were well defined, and three of four malignant tumors were poorly defined. In all cases of sialadenitis, the submandibular gland showed diffusely different signal intensities from the normal gland on both T1-weighted and T2-weighted images. Eight cases of chronic sialadenitis showed lower T2-weighted signal intensities than the normal gland, and this can be explained histopathologically by marked fibrosis and cellular infiltration.CONCLUSIONSMR imaging can show the presence, extent, margins, and signal intensity changes of pathologic conditions of the submandibular gland.  相似文献   

15.
脑膜瘤的MRI表现与组织病理对照研究   总被引:7,自引:2,他引:5  
目的 研究脑膜瘤的磁共振表现与其病理分类之间的关系。方法 回顾分析 12 8例经手术病理证实为脑膜瘤患者的MRI表现。结果 T1WI图像 ,上皮型脑膜瘤 2 9例 ( 4 9% )呈低信号 ,11例 ( 19% )呈稍低信号 ,17例 ( 2 9% )呈等信号。而纤维型脑膜瘤T1WI信号类型分别为 2 3例 ( 5 9% ) ,5例 ( 13 % )和 9例 ( 2 3 % )。在T2 WI图像上 ,3 4例 ( 5 8% )上皮型脑膜瘤呈高信号 ,15例 ( 2 5 % )呈稍高信号 ,10例 ( 17% )呈等信号 ,而纤维型分别为 2例 ( 5 % ) ,8例 ( 2 0 .5 % )和 11例 ( 2 8% )。上皮型、纤维型、移行型在T1WI上均呈现等、低信号 ,而在T2 WI图像上 ,上皮型、血管瘤型及移行型呈现为高信号或稍高信号 ;纤维型脑膜瘤T1WI以低或稍低信号为主。结论 在MRIT1WI图像上 ,各组织学类型之间信号强度的分布无显著性差别 ,而在T2 WI上 ,信号强度与病理类型具有统计学的相关性  相似文献   

16.
One hundred and three patients with known malignancy and suspected bone metastasis underwent magnetic resonance imaging. In 93%, the metastatic lesions, detected both on plain films and radionuclide bone scans, showed decreased signal intensity on T1-weighted images and increased signal intensity on T2-weighted images. All lesions, except one lesion showing much blastic change on plain films, showed contrast enhancement with Gd-DTPA administration. Although further investigation is needed, a correlation between the type of primary malignancy and the signal intensity of the metastatic lesion is suggested. Among 312 metastatic lesions detected by MR imaging, 272 lesions (87%) and 134 lesions (40%) were also detected by radionuclide bone scans and plain films, respectively. In five cases, MR imaging clearly revealed the lesion compressing the spinal cord, which helped us formulate a therapeutic plan. We conclude that MR imaging is the most sensitive examination for detecting bone metastasis and is necessary for planning treatment.  相似文献   

17.
MRI of acute spinal epidural hematomas.   总被引:18,自引:0,他引:18  
PURPOSE: The purpose of this work was to determine the MR findings that characterize acute spinal epidural hematomas (ASEHs). METHOD: The MR findings of 17 patients with ASEH (9 cervical, 7 thoracic, and 2 lumbar) were reviewed. Fifteen of the hematomas were secondary to trauma and two were spontaneous. Correlation with CT (8 cases) and surgical findings (11 cases) was also performed. RESULTS: Imaging findings in ASEH were the following: (a) a variable signal intensity (on T1-weighted images, 10 showed isointensity to cord and 7 were slightly hyperintense; T2-weighted images showed hyperintensity with areas of hypointensity); (b) capping of epidural fat; (c) direct continuity with the adjacent osseous structures; (d) compression of epidural fat, subarachnoid sac, and spinal cord; (e) usually posterolateral location in the spinal canal. CONCLUSION: Epidural hematomas in the spinal canal are lesions capable of producing sudden spinal cord and/or cauda equina compression. MR provides characteristic findings that allow a prompt diagnosis of acute epidural hematomas.  相似文献   

18.
ObjectiveTo study the association between the “dural tail sign” and spinal meningiomas on MR imaging.MethodsRetrospective review of MR examinations of all pathologically proven spinal meningiomas from 1998 to 2005 was performed. Lesions were evaluated for size, signal intensity, enhancement pattern, and presence or absence of dural tail. The dural tail length and direction in reference to the meningioma were also evaluated.ResultsSeven spinal meningiomas were identified in seven patients. One lesion was purely extradural, while the remaining were intradural extramedullary. Dural tail was present in four cases (57%) and its length ranged between 5 and 21 mm. The tail was seen cranial and caudal to the meningioma in three cases and only cranially in one. Coronal images were available in three cases and in two of these; the dural tail was clearly depicted.Conclusions“Dural tail sign” is as common in spinal meningiomas as in cranial meningiomas.  相似文献   

19.
PURPOSETo describe the MR appearance of cystic meningiomas, and to correlate the MR appearance with the surgical and neuropathologic findings.METHODSEight patients with cysts associated with meningiomas were studied on a 1.5-T MR system. Unenhanced sagittal T1- and axial T2-weighted images were obtained in all patients. Axial and coronal gadopentetate dimeglumine-enhanced T1-weighted spin-echo images were obtained in seven patients. Additional sagittal T1-weighted spin-echo contrast-enhanced images were obtained in four patients.RESULTSThe cystic components were intratumoral and eccentric in two cases, intraparenchymal in one case, and extraparenchymal (trapped cerebrospinal fluid) in five cases. Cyst wall enhancement was present in two of seven cases performed with intravenous gadopentetate dimeglumine. There was no correlation between cyst signal intensity and cyst content. A preoperative diagnosis of cystic meningioma was possible in all eight cases.CONCLUSIONSMR demonstrates the extradural location of the tumor and its cystic component, correlates well with the surgical presentation and the neuropathologic results, and allows the preoperative diagnosis of cystic meningioma based on the MR findings. Division into three types of cysts aids the neurosurgeon, who must decide whether total resection is feasible. To obtain total resection and reduce the risk of recurrence with an intratumoral cyst, the surgeon must ensure that the plane of resection is in fact between the thin enhancing membrane of the tumor cyst and the adjacent arachnoid. In cases in which the cyst is trapped cerebrospinal fluid or intraparenchymal in location, the cyst wall adjacent to or within the brain parenchyma is not included in the resection.  相似文献   

20.
目的分析亚急性联合变性颈髓的磁共振成像表现特点,提高对该病的认识.方法收集临床确诊亚急性联合变性累及颈髓的患者5例,回顾性分析其磁共振成像表现,并复习相关临床及文献资料.结果5例患者磁共振成像均显示颈髓不同程度的后、侧索长T2信号,其颈髓正中矢状位T2加权图像均呈连续束带状异常信号;4例行钆喷替酸葡甲胺增强扫描,其中2例可见条片状强化.结论亚急性联合变性的颈髓矢状位束带状改变有比较典型的特点,磁共振成像是诊断该病的重要手段.  相似文献   

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