Dural tail sign in spinal meningiomas

OBJECTIVE: To study the association between the "dural tail sign" and spinal meningiomas on MR imaging. METHODS: Retrospective 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. RESULTS: Seven 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.     

Pathologic significance of the "dural tail sign"

Objective

The exact nature of the “dural tail sign” (thickening of the dura adjacent to the tumour in contrast enhanced T1-MRI imaging) is still not clearly established. In this study we tried to verify the histological appearance of the “dural tail sign” and probable correlation between different MRI findings and dural tail histology.

Material and methods

In this study, 129 patients with intracranial lesions underwent MRI imaging with 1.5 T scanner. The “dural tail sign” was defined using Goldsher et al. criteria. Size and pattern of enhancement of the tumour and adjacent dura was noted in MRI and in the pathologic samples, dural tail and the dura beneath the tumour was assessed.

Results

In 30 cases, “dural tail sign” was evident on MRI, dural tail noted in 17 of these cases in histological samples (12 meningiomas, 3 pituitary adenomas and 2 schwannomas). All of them had vessel dilatation, 6 showed tumoural invasion, 4 demonstrated intravascular growth of the lesion and 1 showed inflammation of the dura.

Conclusion

In our study MRI findings failed to predict tumoural invasion of the dural tail in histologic samples and because of frequent presence of tumour nests in it, the dura matter should be resected as widely as possible.     

颅内血管周细胞瘤与脑膜瘤的MRI表现及鉴别分析

目的探讨颅内血管周细胞瘤(HPC)MR影像特点并与脑膜瘤影像表现进行对比分析。方法回顾性分析6例2015—2017年经中国医科大学附属第一医院确诊的HPC病人[年龄26～75岁,平均(46.33±16.88)岁]及40例颅内脑膜瘤病人[年龄27～78岁,平均(56.12±12.19)岁]的临床及影像资料。所有病人均进行MRI扫描检查,采用χ~2检验对2组病人的影像表现进行比较。结果 HPC与脑膜瘤病人MRI表现相似,常规MRI可表现为肿瘤分叶、瘤体内有囊变坏死、血管流空影、窄基底连接及骨质破坏,且HPC的发生率均高于脑膜瘤(P0.05)。但脑膜瘤增强MRI上脑膜尾征的发生率高于HPC(P0.05)。结论 HPC与脑膜瘤存在的影像差异有助于两者的鉴别诊断。     

恶性脑膜瘤的CT与MRI诊断和鉴别诊断

目的分析恶性脑膜瘤的CT与MRI影像学特征,以提高其定性诊断的正确性。方法回顾性分析经手术与病理证实的9例恶性脑膜瘤的CT与MRI影像学表现,并结合文献进行复习。结果9例恶性脑膜瘤全部发生于脑外,增强后均有明显强化,CT清晰显示肿瘤内钙化、骨质破坏,MR可三维成像,清晰显示肿瘤内囊变、脑膜尾征。结论CT与MRI相辅相成,为恶性脑膜瘤的诊断和鉴别诊断提供重要的信息,结合病人临床资料可进一步提高诊断准确率。     

增强液体衰减反转恢复序列在脑膜瘤诊断中的应用价值

目的 探讨增强液体衰减反转恢复(FLAIR)序列在诊断脑膜瘤中的价值. 资料与方法 38例脑膜瘤患者行增强T1WI和FLAIR成像,比较两种序列增强图像上脑膜瘤的强化方式、"脑膜尾征"的显示、肿瘤强化程度、肿瘤与白质及肿瘤与灰质的对比率(CR)和对比噪声比(CNR). 结果 38例中25例(65.8%)在增强FLAIR上呈环状强化,而增强T1WI上仅7例(18.4%)呈环状强化."脑膜尾征"在增强FLAIR和增强T1WI上的显示率分别为36.8%和47.4%.肿瘤在增强FLAIR和增强T1WI上强化程度分别为57.0和301.3,两者间差异有统计学意义(P＜0.001).增强FLAIR和增强T1WI上肿瘤与灰质CR分别为0.9和1.5,两种序列上肿瘤与白质的CNR分别为50.6和72.6,肿瘤与灰质CNR则为44.3和80.1,两种序列间差异均有统计学意义(P＜0.001).肿瘤与白质CR在两种序列间无差异. 结论 增强FLAIR有助于脑膜瘤包膜的显示和判断,但在显示肿瘤本身及"脑膜尾征"上不及增强T1WI.     

Dural tail sign in spinal meningiomas

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.     

A review on dural tail sign

"Dural tail sign" (DTS) which is a thickening of the dura adjacent to an intracranial pathology on contrast-enhanced T1 MR Images, was first thought to be pathognomonic of meningioma, however, many subsequent studies demonstrated this sign adjacent to various intra- and extra-cranial pathologies and in spinal lesions. In this paper we outline the history, accompanying pathologies and the differentiation and probable pathophysiology of DTS. We also discuss whether we can predict tumoral involvement of the dural tail before surgery and whether the dural tail adjacent to a tumor should be resected.     

Dural invasion of meningiomas adjacent to the tumor margin on Gd-DTPA-enhanced MR images: histopathologic correlation

In intracranial meningiomas a flat, contrast-enhancing, dural structure adjacent to the tumor can occasionally be observed on gadolinium-DTPA-enhanced MR images. We wished to evaluate whether there is a correlation between MR images and meningeal invasion of intracranial meningiomas. The study included 54 patients with intracranial meningioma and the meningeal sign. MR studies included T2-weighted and gadolinium-DTPA-enhanced T1-weighted images in axial, coronal, and sagittal planes. Histopathologic examinations were done on the meningiomas adjacent to the dura mater. The meningeal sign on MRI was observed from 2 up to 35 mm from the main tumor mass in 31 (57 %) of the 54 patients. In 20 of these 31 the histopathologic examination showed tumor invasion, while 11 patients had no tumor invasion but tissue proliferation, hypervascularity, and vascular dilatation. Seven of the 23 meningiomas without the meningeal sign had histologically proven infiltration of the adjacent dura. MR imaging is not able to determine definitive whether or not there is dural infiltration of the meningiomas. In conclusion, resection of the tumor with a wide margin is necessary to achieve complete excision of meningioma and to avoid recurrence. Received 23 July 1997; Revision received 10 October 1997; Accepted 17 October 1997     

脑膜尾征”：与脑膜瘤相关的MR强化表现

目的分析脑膜瘤脑膜尾征的MR表现及组织学特点。方法对32例脑膜瘤患者均行MR平扫及增强扫描。结果32例34个脑膜瘤病灶中有23个病灶（67.6%）显示脑膜尾征,且与肿瘤的大小与位置无关。结论脑膜尾征是脑膜瘤在MR增强扫描时较常见和特有的表现,而且脑膜尾征与肿瘤侵犯脑膜部分相关。     

Intraosseous hemangioma of the skull with dural tail sign: radiologic features with pathologic correlation

Osseous hemangiomas of the calvaria account for about 0.2% of bone neoplasms. We report a case of an extensive intraosseous cavernous hemangioma in a 46-year-old woman. MR imaging showed a mass in the right frontal bone with intra- and extracranial extension and a dural tail sign after gadopentetate dimeglumine administration, mimicking a meningioma in which the dural tail sign was due to a direct noninvasive superficial growth of the lesion.     

The dural tail sign--beyond meningioma

There have been somewhat conflicting reports published about the significance of linear meningeal thickening and enhancement adjacent to peripherally located cranial mass lesions on contrast-enhanced magnetic resonance (MR) images. Most of the authors consider this so-called "dural tail sign" or "flare sign" almost specific for meningioma. This review illustrates the MR imaging findings of a wide spectrum of disorders that show this dural sign. Causes include other extra-axial lesions and also peripherally located intra-axial lesions such as neuromas, chloromas, metastases, lymphoma, gliomas, pituitary diseases, granulomatous disorders, and also cerebral Erdheim-Chester disease. The dural tail sign is not specific to a particular pathological process. Nevertheless, useful conclusions can be drawn from the morphology of the lesion, its enhancement pattern, and its solitary or multifocal presentation. The final diagnosis must be based on cerebrospinal fluid studies or histological studies after biopsy.     

脑膜血管外皮细胞瘤的影像诊断与鉴别诊断

目的 提高对脑膜血管外皮瘤的认识。资料与方法 回顾性分析经手术病理证实的4例脑膜血管外皮瘤的CT和MRI表现，并结合文献进行复习。结果 脑膜血管外皮瘤的CT和MRI表现类似脑膜瘤，但具有恶性征，无颅骨增生和硬膜强化（硬膜尾征），与脑膜瘤不同。结论 CT和MRI表现类似脑膜瘤的颅内肿瘤，具有恶性征，没有颅骨增生和硬膜强化者要考虑脑膜血管外皮瘤的可能。     

"Dural tail sign": a specific MR sign for meningioma?

Somewhat conflicting reports have appeared about the significance of linear meningeal thickening and enhancement adjacent to peripherally located cranial mass lesions on contrast enhanced magnetic resonance images. Some authors consider this finding nearly diagnostic of meningioma. In an attempt to determine the specificity of this so-called tail sign, particularly with respect to meningioma, we retrospectively reviewed 16 cases from institutional records. From our results, the tail sign appears to be highly suggestive but not specific for meningioma.     

Microcystic meningioma: importance of obvious hypointensity on T1-weighted magnetic resonance images

PURPOSE: To investigate the sensitivity and specificity of various magnetic resonance imaging findings for microcystic meningioma. METHODS: Magnetic resonance images of 26 patients with microcystic meningioma (8 from our series and 18 from the literature) and 32 control subjects with other types of meningiomas were evaluated for obvious hypointensity relative to the cerebral cortex on T1-weighted images (T1WIs), obvious hyperintensity relative to the cerebral cortex on T2-weighted images (T2WIs), a radial or sunburst vascular pattern, marginal and reticular enhancement, severe peritumoral brain edema, and the dural tail sign. Differences in the frequencies of these findings between the microcystic and control groups were examined by means of the chi2 test. The sensitivity, specificity, positive predictive value, and negative predictive value of these findings in the diagnosis of microcystic meningioma were calculated. Multivariate analysis of the findings was also performed. RESULTS: The frequencies of obvious hypointensity on T1WI, obvious hyperintensity on T2WI, marginal and reticular enhancement, and severe peritumoral brain edema significantly differed between the microcystic and control groups (all P < 0.005). Sensitivities and specificities of hypointensity on T1WI and hyperintensity on T2WI in the diagnosis of microcystic meningioma were greater than 87%. After multivariate analysis, obvious hypointensity on T1WI was the only significant predictor of microcystic meningioma, with an odds ratio of 75.0 (95% confidence interval, 3.7-1536.0). CONCLUSION: Obvious hypointensity relative to the cerebral cortex on T1WI was the most valuable magnetic resonance finding in the diagnosis of microcystic meningioma.     

Dural enhancement with primary calvarial lesions

The purpose of this study was to relate the pathological and imaging features of dural enhancement and meningeal sign (dural tail) on contrast-enhanced T1-weighted magnetic resonance (MR) images from patients with primary calvarial lesions as well to assess the accuracy of MR imaging in predicting dural invasion. Thirty-two calvarial tumors studied with contrast-enhanced MR imaging and histopathological examination of the dural specimens were reviewed. Sixteen patients presented dural enhancement, eight with tumor invasion. Tumoral invasion of the dura was observed in one case without enhancement. Malignant lesions showed enhanced dura more commonly than benign lesions (P=0.02). Nodular and discontinuous dural enhancement was statistically associated with dural invasion (P=0.05). Dural tail did not show a specific pathological association. Meningeal enhancement is a nonspecific reaction to calvarial lesions unless nodular and discontinuous. False-negative and -positive cases of dural invasion imply some limitation of contrast-enhanced MR imaging in predicting dural invasion by calvarial neoplasms.     

MRI鉴别囊变脑膜瘤与脑表面囊变胶质瘤的价值

目的：探讨囊变脑膜瘤与靠近脑表面囊变胶质瘤的MRI表现,以提高鉴别诊断水平。方法：回顾性分析经术后病理证实的囊变脑膜瘤38例与靠近脑表面囊变胶质瘤21例,分析增强后病灶边缘的＂脑膜尾征＂、＂白质塌陷征＂、＂毛刺征＂及＂指状水肿征＂、＂宽基底征＂及＂强化均匀＂的例数,并作统计学分析。结果：脑膜瘤组的脑膜尾征、白质塌陷征、毛刺征、宽基底征、指状水肿征及肿瘤实质强化均匀的检出率分别为73.7%（28/38）、76.3%（29/38）、10.5%（4/38）、81.6%（31/38）2、3.7%（9/38）及57.9%（22/38）;而胶质瘤组则分别为23.8%（5/21）、19.0%（4/21）、38.1%（8/21）、57.1%（12/21）5、2.4%（11/21）及33.4%（7/21）。白质塌陷征、脑膜尾征、宽基底征、毛刺征及指状水肿征在脑膜瘤组与胶质瘤组差异有统计学意义（P〈0.05）;肿瘤实质强化均匀在二组间差异无统计学意义（P〉0.05）。结论：脑膜尾征、白质塌陷征、宽基底、毛刺征、指状水肿征对鉴别脑膜瘤与胶质瘤价值较大,而强化较均匀对二者的鉴别意义不大。     

The dural tail of intracranial meningiomas on fluid-attenuated inversion-recovery images

We evaluated the dural tail associated with 48 intracranial meningiomas on fluid-attenuated inversion-recovery (FLAIR) and contrast-enhanced T1-weighted images. In 30 (62.5%), a dural tail was observed on contrast-enhanced T1-weighted images, and thickening of the dura mater and abnormal signal were identified in the corresponding region on FLAIR images. Thus, FLAIR imaging was useful for showing dural abnormality associated with meningiomas without the needed for contrast medium.     

Imaging characteristics of Rosai-Dorfman disease in the central nervous system

Background and purpose

Rosai-Dorfman disease (RDD) is a rare, lymphoproliferative disorder of uncertain etiology. The Central Nervous System (CNS) is a very rare site for RDD and only a few imaging appearances have been described. The purpose of this study is to present the largest series of cases in the CNS imaging literature to increase familiarity with this entity and further identify features that may distinguish RDD from meningioma.

Materials and methods

Findings from imaging examinations in 10 patients with pathologically confirmed RDD were retrospectively reviewed. Two radiologists evaluated the lesion location, shape, size, number, edge, cerebral edema, homogeneous or heterogeneous appearance, attenuation and signal intensity, degree of enhancement, and the relation between lesions and meninges.

Results

RDD in CNS showed similar features in imaging: an extra-axial, well-circumscribed, dura-based mass, isodense or hyperdense on CT, isointensity on T1-weighted imaging and isointensity with hypointensity on T2-weighted imaging. The mass enhanced markedly and homogeneously after the administration of contrast agent and demonstrated dural tail sign in all cases. Significant perifocal edema was associated with the masses. Remarkably, seven patients (77.8%) showed strong hypointensity within isointensity on T2-weighted or FLAIR images and no calcification was observed in CT images or pathologic specimens.

Conclusions

Although RDD in the CNS is a rare process, it should be considered in the differential diagnoses for meningioma. We believe that a typical representation of hypointensity irrelevant to calcification on T2-weighted or FLAIR images can suggest the diagnosis of RDD.     

Intracranial adenoid cystic carcinoma mimicking meningioma: report of two cases

Two cases of intracranial adenoid cystic carcinoma mimicking meningioma are reported. In one, MRI showed not only a homogeneously enhancing extra-axial tumour attached to the dura mater of the posterior cranial fossa, but also surrounding dural enhancement, the dural tail sign. In the second, CT demonstrated a well-demarcated enhancing extra-axial tumour, indistinguishable from a sphenoid ridge meningioma extending into the orbit. The neuroradiological features of intracranial adenoid cystic carcinoma may thus closely resemble those of meningioma.     

Dural tail adjacent to acoustic neuroma: MR features

There have been several reports describing the presence of a dural tail on enhanced MR as being specific for or suggestive of meningioma. It has also been stated that it is a specific diagnostic sign in distinguishing meningioma from acoustic neuroma. We report a case of a dural tail in an acoustic neuroma.