Access the full text.
Sign up today, get DeepDyve free for 14 days.
References for this paper are not available at this time. We will be adding them shortly, thank you for your patience.
ORIGINAL RESEARCH ADULT BRAIN Usefulness of a Rim-Enhancing Pattern on the Contrast- Enhanced 3D-FLAIR Sequence and MRI Characteristics for Distinguishing Meningioma and Malignant Dural-Based Tumor T. Panyaping, M. Punpichet, P. Tunlayadechanont, and O. Tritanon ABSTRACT BACKGROUND AND PURPOSE: Meningiomas are the most common type of extra-axial dural-based tumors; however, malignant dural-based tumors can mimic meningiomas on imaging. The aim of this study was to determine the efﬁcacy of differentiating me- ningiomas from malignant dural-based tumors by using rim-enhancement patterns on a contrast-enhanced FLAIR sequence and MR imaging characteristics. MATERIALS AND METHODS: This retrospective study included 102 patients with meningiomas and 31 patients with malignant dural- based tumors who underwent pretreatment MR imaging. The rim-enhancement patterns on contrast-enhanced FLAIR and MR imag- ing characteristics, including the dural tail sign, hyperostosis, bony destruction, leptomeningeal enhancement, peritumoral edema, T2-weighted signal intensity, and tumor enhancement were evaluated. RESULTS: Complete rim enhancement of the tumor-brain interface on contrast-enhanced FLAIR (contrast-enhanced-FLAIR rim sign) was present in most meningiomas (91/102, 89.2%) and at signiﬁcantly greater frequency than in malignant dural-based tumors (2/31, 6.5%) (P, .001). Complete contrast-enhanced FLAIR rim enhancement provided high sensitivity (89.2%), speciﬁcity (93.5%), and accu- racy (90.2%) for diagnosing meningioma. Additionally, hyperostosis was an MR imaging characteristic that suggested a diagnosis of meningioma. In contrast, bony destruction with cortical breakthrough and leptomeningeal enhancement suggested malignant dural- based tumors. There were limitations of meningiomas of ,2.0 cm or at cavernous sinus locations that did not demonstrate con- trast-enhanced FLAIR rim enhancement. CONCLUSIONS: The rim-enhancement pattern on contrast-enhanced FLAIR could help differentiate meningiomas and malignant dural-based tumors. The presence of complete rim enhancement on contrast-enhanced FLAIR was a robust predictive sign for meningioma. ABBREVIATIONS: AUC ¼ area under the curve; CE ¼ contrast-enhanced; NPV ¼ negative predictive value; PPV ¼ positive predictive value; WHO ¼ World Health Organization eningioma is the most common intracranial neoplasm and Meningiomas typically have a dual blood supply in which the extra-axial tumor, representing up to 30% of all adult intra- primary arterial feeders from dural branches or meningeal cranial neoplasms. The World Health Organization (WHO) arteries largely supply the tumor core, generating a “sunburst pat- classifies meningiomas on the basis of their histologic characteris- tern.” In large tumors, recruitment of pial supply from intracranial tics and recurrence risk as follows: grade I, benign (80%); grade arteries to the peripheral parts of the tumor may be seen and pro- II, atypical (18%); and grade III, anaplastic/malignant (2%). vides some specific MR imaging features of rim enhancement on 2,3 contrast-enhanced (CE) FLAIR images. In 2003, Oguz and Cila investigated the enhancement patterns Received October 6, 2022; accepted after revision January 3, 2023. of meningiomas on CE-FLAIR images. Twenty-one meningiomas From the Department of Diagnostic and Therapeutic Radiology, Faculty of Medicine, Ramathibodi Hospital, Mahidol University, Bangkok, Thailand. (70%) showed peripheral (rim) enhancement patterns, which is Please address correspondence to Oranan Tritanon, MD, Department of related to the dual (dural and pial) vascular supply to meningiomas Diagnostic and Therapeutic Radiology, Faculty of Medicine, Ramathibodi Hospital, Mahidol University, 270 Rama VI Rd, Ratchathewi, Bangkok 10400, Thailand; e-mail: more commonly seen in tumors of .2 cm in diameter. In 2005, Oratrita@gmail.com Oner et al found that 85% of meningiomas of .2cm showed Indicates open access to non-subscribers at www.ajnr.org peripheral enhancement on the CE-FLAIR sequence, confirming Indicates article with online supplemental data. http://dx.doi.org/10.3174/ajnr.A7780 the dual vascular supply. In 2014, Enokizono et al revealed that AJNR Am J Neuroradiol 44:247–53 Mar 2023 www.ajnr.org 247 the rim-enhancement patterns on CE-FLAIR were strongly cor- and DWI/ADC sequences. DWI was performed using a single-shot related with the presence of a dual vascular supply, which was echo-planar imaging pulse sequence. Diffusion-sensitizing gradients were applied sequentially along the 3 orthogonal planes, and images evidenced by DSA, and classified the rim-enhancement patterns were obtained at b-values of 0 and 1000 s/mm .ADC maps were on CE-FLAIR into 4 grades by their extent from 0 (no rim visible) generated for all patients using standard software. Routine MR to 3 (rim visible over most of the tumor-brain interface). They imaging protocols with gadolinium (Gd) enhancement were also concluded that the rim-enhancement patterns on CE-FLAIR obtained in CE-T1WI, CE-FLAIR, CE-3D T1 High Resolution of meningioma could predict surgical cleavability and histologic Isotropic Volume Excitation (THRIVE), or BrainVIEW (Philips tumor grade. Healthcare). A standard dose (0.1 mmol/kg) of Gd-DTPA was Meningiomas commonly present as incidental findings on injected at 1.8–2.0 mL/s in all patients using a standard length of IV brain imaging and are treated conservatively or surgically. tubing. After the Gd-DTPA had been injected, CE-3D FLAIR However, approximately 2% of dural-based masses have imaging 7 sequences were first performed in the sagittal plane with the follow- features that mimic meningiomas, including primary dural neo- ing parameters: TR, 4800 ms; TE , 330 ms; TI, 1650 ms; scan time, eff plasms, metastases, granulomatous diseases, various inflammatory 8-11 5minutes;FOV,240 240 mm; matrix size, 368 210; and section diseases, and infections. Thus, distinguishing between meningi- thickness, 1.12 mm. Then, CE-3D THRIVE or BrainVIEW imaging oma and its mimics is essential because clinical management and was performed in theaxial planewith TR, 5–7ms; TE, 3–5ms; flip prognosis can differ significantly, especially for malignant dural- angle, 12°; section thickness, 1 mm; and scan time, 2 minutes. based tumors. Finally, CE T1-weighted imaging was performed with TR, 500 ms; In 2017, Starr and Cha proposed 5 key imaging features to TE, 10 ms; matrix size, 192 240; FOV, 240 240 mm; section differentiate meningioma mimics from meningiomas, including thickness, 4 mm; and scan time, 2 minutes 15 seconds. lack of a dural tail, which was present in 83.7% of meningioma mimics,marked T2hyperintensity (45.9%),marked T2hypoin- Imaging and Postprocessing Analysis tensity (43%), osseous destruction (40.5%), and leptomeningeal Axial CE-T1WI, sagittal CE-3D FLAIR, axial CE-3D THRIVE/ extension (21.6%). In 2021, Nagai Yamaki et al proposed addi- BrainVIEW, axial T2WI, and axial DWI with ADC maps were tional dural displacement signs to predict meningioma mimics. acquired and evaluated in all patients. Multiplanar reconstruc- To the best of our knowledge, no analytic study has used rim- tion was performed in axial, coronal, and sagittal views of the enhancement patterns on CE-FLAIR to differentiate meningiomas CE-FLAIR and CE-3D THRIVE/BrainVIEW images. All MR and malignant dural-based tumors. Therefore, this study aimed to imaging findings were independently reviewed at the PACS distinguish these tumors on the basis of rim-enhancement patterns workstation by 2 neuroradiologists with 10 and 9 years of expe- on CE-FLAIR and MR imaging characteristics. rience in brain MR imaging. The neuroradiologists were blinded to patient data and pathologic diagnoses. MATERIALS AND METHODS First, we evaluated the MR imaging findings including signal Study Setting intensity on T2WI, dural tail (absent or present), osseous destruc- This retrospective study included patients treated at the Department tion (absent, marrow edema, cortex disruption, or cortical break- of Diagnostic and Therapeutic Radiology of Ramathibodi Hospital through), and hyperostosis (absent or present) on T2WI and CE- between January 2015 and May 2020. The study was approved by T1WI sequences. Then we defined the characteristics of rim the Institutional Ethics Committee of Ramathibodi Hospital. enhancement at the tumor-brain interface as a rim with relatively Because of the retrospective nature of the study, the need for high signal intensity on CE-FLAIR. We graded the rim enhance- informed consent was waived. ment patterns from 0 to 3 by their extent as 0, no rim visible; 1, 50% rim visible; 2, .50% rim visible but ,100%; and 3, complete Patient Selection rim enhancement of the tumor-brain interface (100%) (Fig 1). This study included 133 patients with histopathologic diagnoses There was no apparent discrepancy in demonstrating rim enhance- of meningiomas (102 patients) or malignant dural-based tumors ment on CE-3D FLAIR images between 1.5T and 3T scanners by (31 patients) who underwent pretreatment MR imaging of the observation. Additionally, we evaluated leptomeningeal enhance- brain at the Department of Diagnostic and Therapeutic Radiology ment (absent or present) and graded peritumoral brain edema (0 of Ramathibodi Hospital between January 2015 and May 2020. All to 2), which was defined as 0, no edema; 1, edema ,2.0 cm radi- patients underwent surgical resection, and histopathologic diag- ally from the tumor; and 2, edema $2.0 cm radially from the noses were made by an experienced pathologist. The 102 meningi- tumor. On CE-T1WI, we defined the contrast-enhancement pat- omas (1 meningioma per person) were subdivided into 3 groups tern of the tumor as homogeneous or heterogeneous. Any discrep- according to the WHO grading scale: WHO I, WHO II, and ancies in interpretations of MR imaging findings were resolved by WHO III. Demographic data of all patients were collected from consensus. medical records. MR Imaging Protocols and Data Acquisition Statistical Analysis All statistical analyses were performed using STATA Version All MR imaging scans were obtained using 1.5T and 3T scanners 15.1 software (StataCorp). The interobserver agreement in evalu- (Ingenia; Philips Healthcare) with a standard head coil. The patients ating MR imaging characteristics was analyzed using k analysis. were imaged using a routine precontrast brain MR imaging proto- colthat included axialand sagittalT1WI, axialT2WI, axialSWI, A x test was used to ascertain the significance of differences in 248 Panyaping Mar 2023 www.ajnr.org malignant dural-based tumors. Combined MR imaging features in meningiomas and malignant dural-based tumors were also ana- lyzed to predict the diagnosis. RESULTS Summary of Patient Demographics and Tumor Characteristics There were 133 patients with 133 dural-based tumors (1 mass per patient), consisting of meningiomas (102 patients, 76.7%) and malignant dural-based tumors (31 patients, 23.3%). All patient demographics and tumor characteristics are shown in Table 1. All meningiomas in this study were .2.0 cm in diameter. The 102 meningiomas were classified as WHO I (72/102, 70.6%), WHO II (22/102, 21.6%), and WHO III (8/102, 7.8%). The 31 dural-based masses were pathologically diagnosed as malignant dural-based tumors, as detailed in Table 2. Summary of MR Imaging Findings between Meningiomas and Malignant Dural-Based Masses Most meningiomas exhibited complete rim enhancement of the FIG 1. Four different rim-enhancement patterns at the tumor-brain tumor-brain interface on CE-FLAIR sequences (91/102, 89.2%) interface on the CE-FLAIR sequence (arrows). A, Complete rim (Fig 2), which was significantly higher than that in malignant enhancement (CE-FLAIR rim sign). B, Rim enhancement of $50% but dural-based tumors (2/31, 6.5%) (P, .001). Additionally, menin- ,100%. C, Rim enhancement of ,50%. D, No visible rim enhance- giomas frequently showed hyperostosis (76/102, 74.5%), marrow ment. The pathologic results of A, B,and C are meningioma, and D is plasmacytoma. edema (76/102, 74.5%), and homogeneous enhancement on T1WI (75/102, 73.5%), features that were all significantly differ- Table 1: Patient demographics and pathologic findings ent compared with malignant dural-based tumors (P, .001), Meningiomas Malignant Dural-Based which demonstrated hyperostosis (0/31, 0%), marrow edema Variables (n = 102, 76.7%) Tumors (n = 31, 23.3%) (6/31, 19.4%), and homogeneous enhancement on T1WI (9/31, Age (mean) (yr) 51.96 (SD, 10.69) 50.03 (SD, 20.81) 29%). In contrast, malignant dural-based tumors that demon- Sex strated cortical breakthrough (21/31, 67.7%) and leptomeningeal Female 85 (83.3%) 15 (48.4%) Male 17 (16.7%) 16 (51.6%) enhancement (10/31, 32.3%), absence of a dural tail sign (6/31, Size (mean) (cm) 4.37 (SD, 1.91) 4.5 (SD, 2.2) 19.4%), hypointensity on T2WI (8/31, 25.8%), and heterogeneous WHO grade enhancement on T1WI (22/31, 71%) were significantly different I 72 (70.6%) – compared with meningiomas (P, .001), which showed cortical II 22 (21.6%) – III 8 (7.8%) – breakthrough (5/102, 4.9%), leptomeningeal enhancement (0/102, Location 0%), absence of a dural tail sign (2/102, 2%), hypointensity on Convexity 24 (23.5%) 19 (61.2%) T2WI (4/102, 3.9%), and heterogeneous enhancement on T1WI Sphenoid wing 20 (19.6%) 3 (9.6%) (27/102, 26.5%). A summary of the MR imaging findings of Petroclival 18 (17.6%) 1 (3.3%) meningiomas and malignant dural-based tumors is presented in Parafalcine 13 (12.7%) – Cavernous sinus 9 (8.8%) 3 (9.6%) the Online Supplemental Data. Cerebellopontine 6 (5.8%) 1 (3.3%) angle Characteristic MR Imaging Findings That Predict Suprasellar 9 (8.8%) – Meningiomas Foramen magnum 2 (1.9%) – Complete rim enhancement of the tumor-brain interface on the Olfactory groove 1 (0.9%) – CE-FLAIR sequence demonstrated excellent sensitivity (89.2%), Orbit – 3 (9.6%) Prepontine – 1 (3.3%) specificity (93.5%), PPV (97.8%), and NPV (72.5%) and had the Note:—The en dash (–) indicates none. highest accuracy (90.2%) for predicting meningioma. The interob- server agreement was excellent for interpreting rim-enhancement rim-enhancement patterns on CE-FLAIR and other MR imaging patterns on CE-FLAIR sequences, with a k value ¼ 0.902. characteristics between meningiomas and malignant dural-based Furthermore, the analysis of $50% CE-FLAIR rim enhance- tumors and in the subgroup analysis of meningiomas graded ment demonstrated more excellent sensitivity (95.1%), specific- WHO I, WHO II, and WHO III. P values ,.001 were considered ity (93.5%), PPV (98%), NPV (85.3%), and accuracy (94.7%) for statistically significant differences. Furthermore, we calculated the predicting meningioma with a perfect interobserver agreement (k value ¼ 1.0). sensitivity, specificity, positive predictive value (PPV), negative pre- Hyperostosis also showed fair sensitivity (74.5%), excellent dictive value (NPV), and percentage accuracy of each MR imaging characteristic for differentiating between meningiomas and specificity (100.0%), and PPV (100.0%) and had high accuracy AJNR Am J Neuroradiol 44:247–53 Mar 2023 www.ajnr.org 249 (80.5%) for consideration of meningioma. The dural tail sign and Characteristic MR Imaging Findings That Predict marrow edema had high sensitivity but low specificity for pre- Malignant Dural-Based Tumors dicting meningioma (Table 3). Cortical breakthrough demonstrated moderate sensitivity (67.7%) Furthermore, complete or $50% rim enhancement of the tu- with high specificity (95.1%), PPV (80.8%), NPV (90.7%), and the mor-brain interface on the CE-FLAIR sequence (CE-FLAIR rim best accuracy (88.7%) for consideration of malignant dural-based sign) plus hyperostosis demonstrated higher accuracy for diag- tumors. Leptomeningeal enhancement and lack of a dural tail nosing meningiomas of .2.0 cm (area under the curve [AUC] ¼ demonstrated low sensitivity (32.3% and 19.4%, respectively) but 0.953). high specificity (100.0% and 98.0%, respectively), PPV (100.0% and 75.0%, respectively), NPV (82.9% and 80.0%, respectively), Table 2: Characteristics of malignant dural-based tumors and accuracy (84.2% and 79.7%, respectively) for predicting ma- Pathology No. of Cases (n = 31) lignant dural-based tumors (Table 4). Metastasis 18 (58%) A combination of aggressive MR imaging findings including Adenoid cystic carcinoma 5 leptomeningeal enhancement and cortical breakthrough was a Lung (non-small cell) 3 strong predictive sign for malignant dural-based tumors (AUC ¼ Breast (invasive ductal carcinoma) 2 0.911). Squamous cell carcinoma at scalp 2 Urachal carcinoma 1 Thyroid (follicular carcinoma) 1 Subgroup Analysis of MR Imaging Findings and Comparisons Mucoepidermoid carcinoma 1 between Meningiomas of WHO Grades I, II, and III Nasopharynx (SCCA) 1 The frequency of cortical breakthrough was significantly higher Base of tongue (SCCA) 1 in WHO grade III (4/8, 50%) meningiomas than in WHO grades Colon (adenocarcinoma) 1 I and II (1/94, 1%) (P, .001). WHO grade I and II meningiomas Plasmacytoma/multiple myeloma 6 (19.3%) Ewing sarcoma 2 (6.4%) demonstrated homogeneous enhancement on T1WI (73/94, Lymphoma (non-Hodgkin) 2 (6.4%) 77.6%) more often than WHO grade III meningiomas (2/8, 25%). Osteosarcoma 1 (3.4%) A comparison of MR imaging findings of WHO grade I–III Spindle cell carcinoma 1 (3.4%) meningiomas is shown in the Online Supplemental Data. Atypical teratoid/rhabdoid tumor 1 (3.4%) Note:—SCCA indicates squamous cell carcinoma. DISCUSSION Meningiomas are the most common form of intracranial neo- plasms and extra-axial masses and show many specific MR imag- ing findings. However, approximately 2% of dural-based masses have imaging features that mimic meningiomas, specifically ma- lignant dural-based tumors, which can be a diagnostic challenge. During several recent years, a few studies have described rim-enhancement patterns on the CE-FLAIR sequence for diag- nosing meningioma. However, no previous report in the litera- ture has investigated the role of rim enhancement on CE-FLAIR to differentiate meningiomas and meningioma mimics. This is the first study to compare meningiomas with malignant dural- based tumors using rim-enhancement patterns on CE-FLAIR (or CE-FLAIR rim signs). In this study, the presence of a com- FIG 2. CE-FLAIR rim sign in meningiomas at the cerebellomedullary plete CE-FLAIR rim sign showed high sensitivity, specificity, cistern (A) and parafalcine region (B). PPV, and accuracy for predicting meningiomas. Most meningio- Table 3: Characteristic MR imaging findings for predicting meningiomas Variables Sensitivity Speciﬁcity PPV NPV Accuracy Dural tail sign 98.0% 19.4% 80.0% 75.0% 79.7% Marrow edema 79.2% 33.3% 92.7% 13.0% 75.2% Hyperostosis 74.5% 100.0% 100.0% 54.4% 80.5% Complete rim enhancement on CE-FLAIR 89.2% 93.5% 97.8% 72.5% 90.2% Homogeneous enhancement on T1WI 73.5% 71.0% 89.3% 44.9% 72.9% Table 4: Characteristic MR imaging findings for predicting malignant dural-based tumors Variables Sensitivity Speciﬁcity PPV NPV Accuracy Lack of dural tail 19.4% 98.0% 75.0% 80.0% 79.7% Cortical breakthrough 67.7% 95.1% 80.8% 90.7% 88.7% Leptomeningeal enhancement 32.3% 100.0% 100.0% 82.9% 84.2% Heterogeneous enhancement on T1WI 71.0% 73.5% 44.9% 89.3% 72.9% Hypointense signal on T2WI 53.3% 86.2% 66.7% 78.1% 75.0% 250 Panyaping Mar 2023 www.ajnr.org Recent studies suggest that malignant dural-based masses receive vascular sup- ply from various branches of the internal and external carotid arteries according to 14-16 their cell types and locations. No pial vascular supply in the tumor capsule has been described for malignant dural-based masses. However, our study demonstrated 2 cases of malignant dural-based tumors (dural metastasis of squamous cell carci- noma and mucoepidermoid carcinoma) FIG 3. A, Anaplastic meningioma (WHO grade III). CE-FLAIR (A) sequence demonstrates a large extra-axial mass with cortical breakthrough involving the left middle skull base and left temporal with complete rim enhancement on the skull with the CE-FLAIR rim sign (white arrows). Malignant soft-tissue tumor was the favored diag- CE-FLAIR sequence accompanied by aggre- nosis in the initial report. The pathologic result is anaplastic meningioma (WHO grade III). A malig- ssive imaging features, including adja- nant dural-based mass on CE-FLAIR (B) and CE-T1WI fat suppression (C) sequences shows an cent leptomeningeal enhancement and extra-axial heterogeneously enhancing mass at the bilateral frontal convexities that had invaded brain parenchymal invasion. The CE- the anterior-superior sagittal sinus and demonstrates the CE-FLAIR rim sign (white arrows), accompanied by focal leptomeningeal enhancement (asterisk) and adjacent brain parenchymal FLAIR rim sign of these lesions could invasion (black arrow). Meningioma was the favored diagnosis in the initial report. The pathologic be related to prominent pial arterial result was metastatic mucoepidermoid carcinoma. supply at the peripheral portion of the tumors (Fig 3). mas of .2 cm demonstrated complete rim enhancement on CE- In this study, bony hyperostosis demonstrated fair sensitivity FLAIR, similar to the results presented by Oner et al (12/14, 85%). and excellent specificity and PPV, with high accuracy for consider- Furthermore, the presence of $50% CE-FLAIR rim enhancement ation of meningioma, consistent with findings in prior literature. demonstrated more excellent sensitivity, specificity, and accuracy However, lymphomas and immunoglobulin G4–related diseases 18,19 for predicting meningioma. can show hyperostosis that can mimic meningioma, but we These characteristic MR imaging findings have been described did not observe this feature in this study. as possibly related to the dual blood supply (meningeal and pial A dural tail was a hallmark for meningioma, with almost 60% arterial supply) of meningiomas that is commonly seen in tumors prevalence, but several dural-based masses also demonstrated this 20,21 of .2 cm in diameter (21/30, 70%). Because high Gd concentra- feature. The proliferation of meningiomas triggers an inflam- tions induce signal loss in the CE-FLAIR sequence, the high con- matory reaction that results in dural thickening and enhancement. centration of Gd in the central part of meningiomas that is due to In this study, a dural tail was present in 98% of meningiomas and the dominant meningeal supply can suppress the T1 effect and 80.6% of malignant dural-based tumors (P, .001), higher than increase T2 shortening, resulting in relative signal loss or no what was previously reported for the prevalence of dural tails in increased signal; in contrast, the lower concentration of Gd in meningioma mimics by Starr and Cha. Furthermore, in our study, the tumor capsule due to relatively less vascularity related to the the lack of a dural tail demonstrated relatively low sensitivity but pial supply can enhance T1 effects and increase T1 shortening, high specificity for predicting malignant dural-based tumors com- resulting in peripheral contrast enhancement on CE-FLAIR. pared with the study by Starr and Cha. These findings can be observed in the CE-2D FLAIR technique in The presence of cortical breakthrough in dural-based masses the previous studies and the CE-3D FLAIR technique in our represents an aggressive feature with significant bone destruction, study. In addition, the 3D-FLAIR technique has an advantage which is supposed to be found in malignant dural-based tumors over 2D-FLAIR in multiplanar reconstruction, providing a better and WHO grade III meningiomas and is very unusual in WHO evaluation of the rim enhancement on CE-FLAIR. grade I meningiomas. Our study found that cortical breakthrough All meningiomas in this study were .2.0 cm in diameter. had moderate sensitivity, high specificity, good PPV and NPV, Nonetheless, 4 meningiomas with no visible rim enhancement and the highest accuracy for consideration of malignant dural- and 1 meningioma with ,50% rim enhancement on CE-FLAIR based tumors, similar to the results of Starr and Cha. However, were observed. All 4 meningiomas with nonvisible rim enhance- there were 5 cases of meningiomas that demonstrated cortical ment were located in the intracavernous sinuses and received vas- breakthrough. All were anaplastic meningiomas (WHO III) with cular supply in various ways from the ICA (C3–C7 segments), complete rim enhancement on CE-FLAIR sequences, features that ophthalmic artery, or intracranial branches of the external carotid could help suggest anaplastic or malignant meningioma rather artery withoutpial vascular supply exceptfor thosethatextended than malignant dural-based tumors (Fig 3). beyond the cavernous sinus. Such findings represented a limita- Additionally, leptomeningeal enhancement was an excellent tion of using CE-FLAIR rim signs to predict intracavernous me- predictive sign for malignant dural-based tumors and was not ningiomas (Online Supplemental Data). The meningioma that generally seen in meningiomas. Our study demonstrated adjacent demonstrated ,50% CE-FLAIR rim enhancement was located at leptomeningeal enhancement in metastases, lymphoma, atypical the cerebral convexity. The reduced rim enhancement of this teratoid/rhabdoid tumor, and squamous cell carcinoma at the lesion could be related to the relatively poor pial artery supply of scalp, possibly related to the subarachnoid space and brain paren- the tumor. chymal invasion. Therefore, observing associated leptomeningeal AJNR Am J Neuroradiol 44:247–53 Mar 2023 www.ajnr.org 251 and differentiate such cases from malignant dural-based tumors. Future research could use rim-enhancement patterns on CE- FLAIR and other MR imaging findings to differentiate meningio- mas and other benign dural-based masses such as hemangioperi- cytomas and infectious/inflammatory dural-based lesions, which can mimic each other and make diagnostics challenging. CONCLUSIONS Complete or $50% rim enhancement on the CE-FLAIR sequence (CE-FLAIR rim sign) showed high accuracy for diagnosing me- ningiomas of .2.0 cm. Hyperostosis was another helpful MR FIG 4. A, CE-T1WI fat suppression sequence demonstrates an extra- imaging finding for predicting meningioma. Aggressive MR imag- axial mass at the right frontoparietal convexity with a dural tail sign ing findings including cortical breakthrough and leptomeningeal that resembles a meningioma. B, CE-FLAIR sequence. No rim enhance- enhancement were strong predictive signs of malignant dural- ment on the tumor-brain interface is observed. Meningioma was based tumors. the favored diagnosis in the initial report. The pathologic result was osteosarcoma. Disclosure forms provided by the authors are available with the full text and PDF of this article at www.ajnr.org. enhancement could alert radiologists that a dural-based mass is unlikely to be a meningioma. REFERENCES Hypointensity on T2WI is a feature that is not commonly seen 1. Osborn AG. Brain Imaging, Pathology, and Anatomy. 2nd ed. Elsevier; in meningiomas and generally indicates hypercellularity, large 2017:659–94 areas of calcification, or significant fibrous tissue in the tumor, 2. Starr CJ, Cha S. Meningioma mimics: five key imaging features to which are variably present in meningioma mimics. In this study, differentiate them from meningiomas. Clin Radiol 2017;72:722–28 25.8% (8/31) of malignant dural-based tumors showed hypointen- CrossRef Medline 3. Kelly M. Tumors. In: Krings T, Geibprasert S, ter Brugge KG eds. sity on T2WI. They were metastases, plasmacytoma/multiple Case-Based Interventional Neuroradiology. Thieme Medical Publishers; myeloma, and osteosarcoma (Fig 4). The frequency of hypointen- 2011:207–12 sity on T2WI was lower compared with the findings of Starr and 4. Oguz KK, Cila A. Rim enhancement of meningiomas on fast FLAIR Cha, in which 43% of malignant dural-based tumors had hypoin- imaging. Neuroradiology 2003;45:78–81 CrossRef Medline tensity on T2WI. Homogeneous or heterogeneous enhancement 5. Oner AY, Tokgöz N, Tali ET, et al. Imaging meningiomas: is there a on T1WI was variable in each tumor type and histologic subtype need for post-contrast FLAIR? Clin Radiol 2005;60:1300–05 CrossRef Medline of meningioma. 6. Enokizono M, Morikawa M, Matsuo T, et al. The rim pattern of me- Thus, combining these MR imaging findings could lead to ningioma on 3D FLAIR imaging: correlation with tumor-brain ad- high accuracy in differentiating meningioma and malignant hesion and histological grading. Magn Reson Med Sci 2014;13:251– dural-based tumors. Complete or $50% rim enhancement of the 60 CrossRef Medline tumor-brain interface on the CE-FLAIR sequence (the CE- 7. Ghosal N, Dadlani R, Gupta K, et al. A clinicopathological study of diagnostically challenging meningioma mimics. J Neurooncol FLAIR rim sign) plus hyperostosis demonstrated higher accuracy 2012;106:339–52 CrossRef Medline for diagnosing meningiomas of .2.0 cm (AUC ¼ 0.953), except 8. Smith AB, Horkanyne-Szakaly I, Schroeder JW, et al. From the radio- for those at an intracavernous location. However, CE-FLAIR rim logic pathology archives: mass lesions of the dura: beyond meningi- signs were found in a few malignant dural-based masses, where oma-radiologic-pathologic correlation. Radiographics 2014;34:295– they were accompanied by leptomeningeal enhancement and 312 CrossRef Medline 9. Nayak L, Abrey LE, Iwamoto FM. Intracranial dural metastases. brain parenchymal invasion. Therefore, aggressive MR imaging Cancer 2009;115:1947–53 CrossRef Medline findings including leptomeningeal enhancement and cortical 10. Lee EK,Lee EJ,Kim MS,et al. Intracranial metastases: spectrum of breakthrough were strong predictive signs of malignant dural- MR imaging findings. Acta Radiol 2012;53:1173–85 CrossRef Medline based tumors (AUC ¼ 0.911). In this study, cortical break- 11. Meyers SP, Hirsch WL Jr, Curtin HD, et al. Chondrosarcomas of the through was present in 4 cases of WHO grade III meningiomas. skull base: MR imaging features. Radiology 1992;184:103–08 CrossRef However, these cases also had complete CE-FLAIR rim signs, Medline 12. Nagai Yamaki V, de Souza Godoy LF, Alencar Bandeira G, et al. Dural- findings that were highly suggestive of meningioma with aggres- based lesions: is it a meningioma? Neuroradiology 2021;63:1215–25 sive behavior. Regarding the results from our study, we have pro- CrossRef Medline posed the diagnostic framework for differentiating meningioma 13. Schramm J. Advances and Technical Standards in Neurosurgery.Vol and malignant dural-based tumor, which is shown in the Online 43. Springer-Verlag; 2015:103–22 Supplemental Data. 14. Lyndon D, Lansley JA, Evanson J, et al. Dural masses: meningiomas and their mimics. Insights Imaging 2019;10:11 CrossRef Medline Our study had some limitations, including its single-institution 15. Hayt DB, Blatt CJ, Goldman SM, et al. Hypervascular presentation nature, no evaluation of tumors of ,2.0 cm in diameter, and a of multiple myeloma involving the skull, demonstrated on ence- small number of WHO grade III meningiomas. Further studies phaloscintigraphy. JNucl Med 1979;20:125–26 Medline should include more patients, specifically with WHO grade III 16. Whitehead RE, Melhem ER, Kasznica J, et al. Telangiectatic osteo- meningioma. Nevertheless, this study is the first step toward using sarcoma of the skull base. AJNR Am J Neuroradiol 1998;19:754–57 rim-enhancement patterns on CE-FLAIR to predict meningioma Medline 252 Panyaping Mar 2023 www.ajnr.org 17. Siegelman ES, Mishkin MM, Taveras JM. Past,present,and future of 20. Wilms G, Lammens M, Marchal G, et al. Thickening of dura surround- radiology of meningioma. Radiographics 1991;11:899–910 CrossRef ing meningiomas: MR features. J Comput Assist Tomogr 1989;13:763– Medline 68 CrossRef Medline 18. Paiva J, King J, Chandra R. Extra-axial Hodgkin’slymphoma with bony 21. Wilms G, Lammens M, Marchal G, et al. Prominent dural enhance- hyperostosis mimicking meningioma. JClin Neurosci 2011;18:725–27 ment adjacent to nonmeningiomatous malignant lesions on contrast- CrossRef Medline enhanced MR images. AJNR Am J Neuroradiol 1991;12:761–64 Medline 19. Lin CK, Lai DM. IgG4-related intracranial hypertrophic pachyme- 22. Kunimatsu A, Kunimatsu N, Kamiya K, et al. Variants of meningio- ningitis with skull hyperostosis: a case report. BMC Surg 2013;13:37 mas: a review of imaging findings and clinical features. Jpn J Radiol CrossRef Medline 2016;34:459–69 CrossRef Medline AJNR Am J Neuroradiol 44:247–53 Mar 2023 www.ajnr.org 253
American Journal of Neuroradiology – American Journal of Neuroradiology
Published: Mar 1, 2023
Access the full text.
Sign up today, get DeepDyve free for 14 days.