Imaging and spectroscopic findings in meningioangiomatosis

Meningioangiomatosis: Multimodal Analysis and Insights From a Systematic Review

BACKGROUND

Meningioangiomatosis is a poorly studied, rare, benign, and epileptogenic brain lesion.

OBJECTIVE

To demonstrate that surgical resection and a short-time interval to surgery improves epileptic seizure control, we performed a systematic review and meta-analysis of meningioangiomatosis cases.

METHODS

Using PRISMA-IPD guidelines, the authors performed a systematic review and meta-analysis of histopathologically-proven meningioangiomatosis cases. Literature search in French and English languages (PubMed, Embase, the Cochrane Library, and the Science Citation Index) including all studies (January 1981 to June 2020) dealing with histopathologically-proven meningioangiomatosis, without age restriction. We assessed clinical, imaging, histomolecular, management, and outcome findings of patients with meningioangiomatosis.

RESULTS

Two-hundred and seven cases of meningioangiomatosis from 78 studies were included. Most meningioangiomatosis was sporadic, preferentially concerned male patients, younger than 20 years old, and allowed a functionally independent status. Epileptic seizure was the main symptom, with 81.4% of patients having uncontrolled seizures at the time of surgery. Meningioangiomatosis mainly had frontal (32.3%) or temporal (30.7%) locations. Imaging presentation was heterogeneous, and the diagnosis was often missed preoperatively. The histopathologic pattern was similar whatever the clinical presentation, and immunohistochemistry had limited diagnostic value. On molecular analysis, allelic loss at 22q12 was more frequent in samples of meningioangiomatosis-associated meningioma (37.5%) than in isolated meningioangiomatosis (23.1%). Time interval from diagnosis to surgery (p = 0.011) and lack of surgical resection of the meningioangiomatosis (p = 0.009) were independent predictors of postoperative seizure control.

CONCLUSIONS

Owing to low scientific evidence, a multicentric prospective study should help refining the management of meningioangiomatosis.

Pediatric Meningeal Tumors of the Sylvian Fissure Region without Dural Attachment: A Series of Three Patients and Review of the Literature

Pediatric meningeal tumors are rare, but those in the region of the sylvian fissure without dural attachment are extremely rare, with only 24 previously reported cases in the world literature. In this series, we report two additional cases of sylvian fissure meningioma without dural attachment and one case of perisylvian meningioangiomatosis in the medial temporal lobe. All three patients presented with complex partial seizures, but the diagnosis was delayed in each case because the symptoms were misinterpreted to be behavioral rather than epileptic. The seizures were eventually confirmed with electroencephalogram, and subsequent imaging showed enhancing masses within the sylvian fissure region that were at least partially calcified in all three cases. Each patient underwent craniotomy. In the first case, gross total resection was achieved, and in the second case, a small residual portion of tumor was densely calcified and adherent to the middle cerebral artery branches. Both of these were World Health Organization (WHO) grade I meningiomas. The third patient underwent biopsy and limited resection of meningioangiomatosis. No dural attachments were noted in any of the tumors, but one of the meningiomas was intraparenchymal in location, surrounding the sylvian fissure in both the frontal and temporal lobes, which has been described in only a small number of these cases previously. The patients underwent pre- and postsurgical neuropsychiatric testing and did not experience any significant cognitive deficits. At 10-year follow-up, the patient who had gross total resection of the tumor has had no recurrence and is seizure-free without anticonvulsant medications. The incompletely resected intraparenchymal meningioma in the second patient recurred after 5 years, however, and at repeat surgery was found to have transformed to a WHO grade II tumor. Radiation therapy was delivered and the tumor has been stable for 2 years, but the patient continues to have occasional seizures despite medication. The patient with meningioangiomatosis has had no further growth and has excellent control of seizures but remains on medication. We review the clinical presentation of these rare tumors and discuss the treatment, outcomes, and possible relationship of meningiomas to meningioangiomatosis.

Three cases of sporadic meningioangiomatosis with different imaging appearances: case report and review of the literature

Background

Meningioangiomatosis (MA) is a rare meningiovascular malformation or hamartomatous lesion in the central nervous system. Radiographic findings of MA may show a variety of characteristics according to different histological components. We present three cases of sporadic MA with different imaging appearances in an attempt to identify specific imaging characteristics.

Case presentation

In case 1, an irregular hyperdense solid mass was localized in the left middle cranial fossa, demonstrating low and equal signal intensity on T1-weighted imaging (T1WI; TR/TE 2,048.9 ms/26.1 ms), high signal intensity with multiple flow void effect on T2-weighted imaging (T2WI; TR/TE 4,000 ms/106.4 ms), and significant and homogeneous enhancement on post-contrast magnetic resonance imaging (MRI). In case 2, the lesion in the right insular lobe showed a cystic-mural nodule pattern. The cystic content demonstrated similar density or signal intensity as cerebrospinal fluid, while the mural nodule demonstrated equal density or signal intensity on computed tomography (CT) and MRI. On post-contrast MRI, the mural nodule showed significant enhancement, but the cystic wall and content showed no enhancement. In case 3, a remarkably enhanced solid nodule was found in the cortex of the left parietal lobe with multiple small cysts surrounding it. This nodule showed low signal intensity on T2WI and diffusion-weighted imaging (DWI; TR/TE 6,000 ms/96.8 ms, b = 1,000 s/mm²). The preoperative diagnoses of the above three cases were meningioma, hemangioblastoma, and ganglioglioma. However, all were pathologically diagnosed as MA.

Conclusion

The presented cases demonstrate that MA may present with solid and cystic imaging patterns, which may include large cystic-mural nodules and small intra- and extra-cystic patterns. Although MA imaging diagnoses are difficult, several MRI signs may include specific characteristics, such as a flow void effect on T2WI and separating cysts in the cystic MA (as shown in our cases), gyriform hyperintensity on T2-fluid attenuated inversion recovery (FLAIR) sequence, and susceptibility artifacts on T2 gradient echo (GRE) sequences (as found in the literature).

Meningioangiomatosis: a case report and literature review emphasizing diverse appearance on different imaging modalities

Purpose. Meningioangiomatosis (MA) is a rare, benign lesion that commonly mimics other intracranial malformations in clinical presentation and appearance on imaging. The case presented and the literature review performed highlight the importance of combining MRI and CT results to better characterize intracranial lesions and including MA on the list of differential diagnoses of patients presenting with seizures. Methods. The case described is of a 19-year-old male with a 10-year history of worsening seizures refractory to multiple drug regimens. MRI revealed an atypical vascular malformation. The patient underwent surgical resection of the epileptogenic cortex. Results. Although the radiologic impression of the lesion was a vascular malformation, pathological examination revealed MA. A literature search performed highlights the variability of the appearance of MA on CT and MRI and suggests the utility of the T2 GRE sequence in illustrating the presence of calcification and, in a lesion with other characteristic features, the diagnosis of MA. Conclusion. MA can be a difficult diagnosis to make based on imaging findings alone. However, in a patient with a characteristic history and presentation, the presence of a calcified mass on CT and MRI brain susceptibility artifact on a T2 GRE sequence may suggest MA.