Meningioangiomatosis. A comprehensive analysis of clinical and laboratory features

Encephalic meningioangiomatosis in a dog with high-grade undefined glioma

Meningioangiomatosis (MA) is a rare proliferative meningovascular disorder that affects mainly the cerebral cortex, brainstem and spinal cord of humans and animals and can coexist with other proliferative disorders. A 7.5-year-old male Brazilian Campeiro Bulldog died after a convulsive crisis and cardiorespiratory arrest. At necropsy, a firm, white mass involving the piriform and right occipital lobes was seen. Histologically, the mass consisted of two morphologically distinct entities that collided: a congenital malformation characterized by a proliferation of meningothelial cells around blood vessels, within the perivascular spaces; and a neoplasm composed of two cell populations with astrocytic and oligodendrocytic differentiation. Meningothelial cells and neoplastic glial cells immunolabelled for vimentin. This first reported case of encephalic MA with a high-grade undefined glioma in a dog was confirmed through clinical signs, pathological and immunohistochemical findings.

Meningioangiomatosis with Skull Erosion

Meningioangiomatosis (MA) is a rare, poorly studied brain hamartomatous lesion, the etiology of which is not fully elucidated. It typically involves the leptomeninges, extending to the underlying cortex, characterized by small vessel proliferation, perivascular cuffing, and scattered calcifications. Given its close proximity to, or direct involvement of, the cerebral cortex, MA lesions typically manifest in younger patients as recurrent episodes of refractory seizures, comprising approximately 0.6% of operated-on intractable epileptic lesions. Due to the absence of characteristic radiological features, MA lesions constitute a significant radiological challenge, making them easy to miss or misinterpret. Although MA lesions are rarely reported with still-unknown etiology, it is prudent to be aware of these lesions for prompt diagnosis and management to avoid morbidity and mortality associated with delayed diagnosis and treatment. We present a case of a young patient with a first-time seizure caused by a right parieto-occipital MA lesion that was successfully excised via an awake craniotomy, achieving 100% seizure control.

Pure and non-pure meningioangiomatosis of 36 Chinese patients: an analysis of clinical presentation, diagnosis, histopathology and prognosis

Meningioangiomatosis (MA) is a disease that is extremely rarely reported. Sporadic MA is occasionally combined with meningioma or other lesions (identified as non-pure MA). This retrospective study investigated the difference between pure MA and non-pure MA by exploring clinical manifestations, histopathology characteristics, and outcomes of MA after surgery. We reviewed the medical records of 36 histopathologically confirmed MA patients (18 pure MA and 18 non-pure MA) who received surgery at our institution between 2012 and 2021. We compared differences in demographic, clinical, imaging, pathological features, and surgical outcomes between pure MA and non-pure MA through descriptive statistics. Compared to non-pure MA, pure MA presented with a more prominent male predilection (5:1 vs. 1.57:1, P = 0.264), a higher seizure incidence (83.3% vs 50.0%, P = 0.038), a more seizure type of GTCS (14/15 vs 5/9, P = 0.047), a less prominent enhancement on MRI (27.8% vs 88.9%, P < 0.001) and a preference of temporal and frontal lobe (100% vs 44.4%, P < 0.001). The differences in clinical characteristics between pure MA and non-pure MA demonstrate their disparate biological natures. Pure MA seems to be a non-neoplastic lesion, while non-pure MA is commonly combined with meningioma, which is a neoplastic lesion. A correct differential diagnosis can be achieved via a triad of the type of seizure, the location of lesion and the radiological presentation. MA is curable and the prognosis is excellent as most patients are free of seizure and recurrence after surgical treatment.

Cystic meningioangiomatosis and cerebellar ependymoma in a child with neurofibromatosis type 2

We report a case of multifocal cystic meningioangiomatosis (MA), an exceptionally uncommon diagnosis even in patients with type 2 neurofibromatosis (NF2). A 2-year-old male with personal as well as family history of genetically-confirmed NF2 presented with incidental findings of MA after imaging for closed-head injury. Computed tomography and magnetic resonance imaging revealed multifocal subcortical and basal ganglia cysts, enhancing tumor-like vascular encasement, and a cerebellar ependymoma with atypical features. Given the paucity of available literature describing this pathology, imaging findings are discussed to further characterize this elusive disease. Radiologists must keep in mind that children with NF2 may not only present with MA, but also a constellation of MA with classic NF tumors, including ependymoma as in this case.

Molecular Alterations in Meningioangiomatosis Causing Epilepsy

Meningioangiomatosis (MA) is a rare process at the intersection of cerebral developmental and neoplastic disorders that often results in epilepsy. We evaluated molecular alterations in MA to characterize its biology and pathogenesis. We searched a comprehensive institutional database for patients with MA treated between 2004 and 2019. Demographic, clinical, surgical, and radiographical data were collected. MA and associated meningioma tissues were evaluated using a next-generation sequencing assay interrogating 1425 cancer-related genes. We studied 5 cases: 3 with MA and 2 with MA associated with a meningioma. Of the MAs associated with a meningioma, 1 had deletions in the NF2 gene in both the MA and the meningioma components, whereas the other had an NF2 deletion in only the MA component. Additional mutations were identified in the MA components, suggesting that MA arises from the meningioma rather than the meningioma resulting from a transformation of the MA. The 3 cases of pure MA showed variants of unknown significance with no alterations in known oncogenic drivers. Our findings provide a starting point to a better understanding of the pathogenesis of this rare lesion. Our study indicates that MA-meningiomas have a neoplastic nature that differs from the hamartomatous/developmental nature of pure MA.

Meningioangiomatosis: an uncommon cause of focal epilepsy with characteristic neuroimaging and neuropathology

A 3-year-old boy presented with acute onset of prolonged right sided focal seizures with secondary generalisation. The investigation findings were suggestive of a neoplastic process more than an inflammatory process. Decision to perform brain biopsy from the lesion to establish the precise nature of lesion was undertaken.

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.

A Review of Proliferative Vascular Disorders of the Central Nervous System of Animals

In disease, blood vessel proliferation has many salient roles including in inflammation, when granulation tissue fills superficial defects, or in the recanalization of an occluded blood vessel. Sometimes angiogenesis goes awry-granulation can be exuberant, and plexiform proliferation of vascular components can contribute to pulmonary hypertension. This review focuses on the diverse manifestations of pathologic vascular overgrowth that occur in the brain, spinal cord, and meninges of animals from birth until old age. Entities discussed include systemic reactive angioendotheliomatosis in which glomeruloid vascular proliferations are encountered in various organs including the central nervous system (CNS). The triad of CNS vascular malformations, hamartomas, and benign vascular proliferations are an especially fraught category in which terminology overlap and the microscopic similarity of various disorders makes diagnostic classification incredibly challenging. Pathologists commonly take refuge in "CNS vascular hamartoma" despite the lack of any unique histopathologic features and we recommend that this diagnostic category be abandoned. Malformative lesions that are often confusing and have similar features; the conditions include arteriovenous malformation, cavernous angioma, venous angioma, and capillary telangiectases. Meningioangiomatosis, a benign meningovascular proliferation with dual components, is a unique entity seen most commonly in young dogs. Last, accepted neoplastic conditions range from lower-grade locally acquired growths like hemangioblastoma (a tumor of mysterious interstitial stromal cells encountered in the setting of abundant capillary vasculature proliferation), the rare hemangioendothelioma, and the highly malignant and invariably multifocal metastatic hemangiosarcoma. Additionally, this review draws on the comparative medical literature for further insights into this problematic topic in pathology.

Meningioangiomatosis: Clinical, Imaging, and Histopathologic Characteristics

Meningioangiomatosis is a rare benign lesion involving the central nervous system. Radiographic appearance can be highly variable which makes pre-operative diagnosis difficult. In this report, we describe meningioangiomatosis in a previously healthy 17-year-old woman who presented with seizures and continued headache and dizziness. This patient presented with a predominately calcified lesion on imaging and eventually underwent near total resection. Meningioangiomatosis is difficult to preoperatively identify, but is an important consideration as prognosis with surgical resection is typically good.

Meningioma with rhabdoid features combined with meningioangiomatosis in infancy: a novel combination

Meningioangiomatosis is a rare histologically distinct abnormality that is occasionally associated with intracranial meningioma. The rhabdoid variant of meningioma is also uncommon and is classified as a World Health Organization Grade III tumour. We report a case of meningioangiomatosis in conjunction with a meningioma with prominent rhabdoid features, in an infant male who underwent complete surgical resection of the lesion. The patient has been followed up for 6 years with no disease recurrence. To our knowledge, this is the first report in the literature describing meningioangiomatosis combined with a meningioma with rhabdoid features.

An update on the CNS manifestations of neurofibromatosis type 2

Neurofibromatosis type II (NF2) is a tumor predisposition syndrome characterized by the development of distinctive nervous system lesions. NF2 results from loss-of-function alterations in the NF2 gene on chromosome 22, with resultant dysfunction of its protein product merlin. NF2 is most commonly associated with the development of bilateral vestibular schwannomas; however, patients also have a predisposition to development of other tumors including meningiomas, ependymomas, and peripheral, spinal, and cranial nerve schwannomas. Patients may also develop other characteristic manifestations such as ocular lesions, neuropathies, meningioangiomatosis, and glial hamartia. NF2 has a highly variable clinical course, with some patients exhibiting a severe phenotype and development of multiple tumors at an early age, while others may be nearly asymptomatic throughout their lifetime. Despite the high morbidity associated with NF2 in severe cases, management of NF2-associated lesions primarily consists of surgical resection and treatment of symptoms, and there are currently no FDA-approved systemic therapies that address the underlying biology of the syndrome. Refinements to the diagnostic criteria of NF2 have been proposed over time due to increasing understanding of clinical and molecular data. Large-population studies have demonstrated that some features such as the development of gliomas and neurofibromas, currently included as diagnostic criteria, may require further clarification and modification. Meanwhile, burgeoning insights into the molecular biology of NF2 have shed light on the etiology and highly variable severity of the disease and suggested numerous putative molecular targets for therapeutic intervention. Here, we review the clinicopathologic features of NF2, current understanding of the molecular biology of NF2, particularly with regard to central nervous system lesions, ongoing therapeutic studies, and avenues for further research.

Sporadic Meningioangiomatosis Presenting as a Middle Cranial Fossa Arachnoid Cyst

BACKGROUND

Meningioangiomatosis is an extremely rare meningovascular disease of the central nervous system that is characterized by the proliferation of leptomeninges, cortical vessels, and perivascular spindled cells. Although it is a benign, neoplastic disorder that carries a good prognosis after surgical excision, initial diagnosis may be challenging as radiologic findings are often variable and nonspecific.

CASE DESCRIPTION

In this report, we describe an unusual presentation of meningioangiomatosis presenting as a symptomatic middle cranial fossa arachnoid cyst.

CONCLUSIONS

In view of the unexpected diagnosis and infrequency of this condition, the case is discussed in collaboration with current literature and management strategies.

B-cell central nervous system lymphoma developing in a patient with cerebral meningioangiomatosis

Meningioangiomatosis is a rare congenital hamartomatous malformation of the leptomeninges that can also involve the adjacent cerebral tissue, sometime arising in association with neurofibromatosis. Here we report the case of a 55-year-old man with neuroradiological evidence of meningioangiomatosis, known to be a well-defined malformative-dysplastic lesion, preceding the onset of central nervous system B-cell lymphoma. We describe for the first time this unusual association, highlighting how meningioangiomatosis could accompany different pathologies more frequently than thought.

Meningioangiomatosis: A review of the variable manifestations and complex pathophysiology

Meningioangiomatosis (MA) is a rare, complex and heterogeneous disease of meningovascular proliferation that is found primarily in the leptomeninges and cerebral cortex but can involve subcortical white matter and other brain regions such as the cerebellum and deep gray matter. MA may be found in pediatric or adult populations and may be sporadic or neurofibromatosis-associated. The presentation of MA is highly variable: it may be associated with other neurological diseases; clinically presents on a spectrum from asymptomatic to seizures or focal deficits; radiologically presents with multifocal, tumor-like, or cystic lesions, or may appear normal; and pathologically may have cellular or vascular predominance. In this article, we review the various manifestations of MA including neurofibromatosis-associated MA, multifocal MA, cystic MA, and MA associated with meningioma, other brain tumors, focal cortical dysplasia, neurodegenerative changes, and post-radiation changes. The treatment of MA is also reviewed. While the pathogenesis of MA remains elusive, we discuss the proposed theories such as developmental, dysplastic, hamartomatous or reactive ethology in given variants. It is important for physicians to be aware of MA as more research on this complex entity is needed and timely diagnosis may benefit outcomes in patients with MA.

Helical tomotherapy for meningiomas of the skull base and in paraspinal regions with complex anatomy and/or multiple lesions

Aim

To evaluate helical tomotherapy for the treatment of complex-shaped uni- or multifocal meningiomas.

Methods and materials

Between 2007 and 2009, 12 patients with complex-shaped meningiomas and/or multiple meningioma lesions were treated with helical tomotherapy. Histologic classification according to the most recent WHO classification for brain tumors was WHO grade I meningioma in 5 patients, atypical WHO grade II meningioma in 5 patients, and anaplastic WHO grade III meningioma in 2 patients. Eight patients were treated with primary radiotherapy, and in 4 patients tomotherapy was performed as re-irradiation for recurrent tumors.

Results

All patients were alive at the time of this analysis. Treatment was well tolerated by all patients. No severe side effects were observed. Four of 12 patients developed progression during follow-up at 2, 4, 17 and 29 months after radiotherapy. Of these, 2 patients were diagnosed with anaplastic meningiomas, and 2 patients suffered from atypical meningioma. Tumor progression developed after primary radiotherapy in 2 patients, and 2 recurrences developed after re-irradiation.

Conclusions

Helical tomotherapy can help meet the challenge of treating complex-shaped meningiomas in critical locations with one or multiple lesions due to the excellent dose distributions and the favorable clinical results.

Adult Brain Tumors and Pseudotumors: Interesting (Bizarre) Cases

Some brain tumors results are interesting due to their rarity at presentation and overwhelming imaging characteristics, posing a diagnostic challenge in the eyes of any experienced neuroradiologist. This article focuses on the most important features regarding epidemiology, location, clinical presentation, histopathology, and imaging findings of cases considered "bizarre." A review of the most recent literature dealing with these unusual tumors and pseudotumors is presented, highlighting key points related to the diagnosis, treatments, outcomes, and differential diagnosis.

Sporadic meningioangiomatosis with and without meningioma: analysis of clinical differences and risk factors for poor seizure outcomes

BACKGROUND

Meningioangiomatosis (MA) is a rare cerebral lesion. Sporadic MA occasionally combines with meningioma (MA-M). The aim of the present study was to clarify whether MA-M and pure MA have clinical differences and to determine risk factors for unsatisfactory seizure outcomes in sporadic MA.

METHODS

We reported 14 sporadic MA cases in our center and conducted a literature review. We compared the demographic, clinical, imaging, electrophysiological and pathological features and surgical outcomes. Logistic regression analysis was performed to evaluate the risk factors for poor seizure outcomes.

RESULTS

MA-M cases showed a more prominent male predilection (4.2 times vs. 1.6 times, p = 0.04), a shorter duration of symptoms (2.8 ± 0.8 years vs. 5.2 ± 0.6 years, p = 0.02), and a lower seizure incidence (53.6 % vs. 89.3 %, p < 0.001) as compared to pure MA. A gyriform alteration on imaging was exclusively associated with pure MA. The Ki-67 was higher in the meningioma component than in the MA component in MA-M (1.2 ± 0.3 % vs. 6.1 ± 1.1 %, p < 0.001). Lesions located in the temporal lobe predicted poor seizure outcomes (p = 0.02, OR = 4.4, 95 % confidence interval, 1.24-15.89).

CONCLUSION

Clinical differences may be caused by the different biological natures. MA-M seems to be a neoplastic lesion, while pure MA seems to be a non-neoplastic lesion. Long-term follow-up is required for MA-M. Because the coexistence of hippocampal sclerosis may explain the poor seizure outcomes of MA located in the temporal lobe, it is important to identify underlying hippocampal sclerosis and to perform complete resection.

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 in a second trimester fetus

We describe to our knowledge the first case of meningioangiomatosis identified in a second trimester fetus. A 30-year-old pregnant woman was attended at our hospital for a second-trimester ultrasound screening scan. With a diagnosis of partial agenesis of the corpus callosum, the parents requested termination of the pregnancy. At autopsy, frontal serial sections of the fetal brain disclosed a short corpus callosum that lacked the posterior splenium, confirming the sonographic diagnosis. At close inspection, a slight bilateral hardening of both medial aspects of the frontal lobes and anterior genu of the corpus callosum was found associated with meningeal adhesion between both frontal lobes. Microscopically, cerebral cortex and corpus callosum were permeated by intersecting bundles of spindle cells with eosinophilic cytoplasm and bland, round nuclei, with a fibroblast or meningothelial-like appearance surrounding abundant blood vessels, consistent with the diagnosis of meningioangiomatosis. According to this finding, meningioangiomatosis must be included in the differential diagnosis of meningocortical fetal lesions.

Multicystic meningioangiomatosis

Background

Meningioangiomatosis (MA) is a rare hamartomatous lesion. Only six cases of cystic MA have been reported in the literature.

Case presentation

We present a case of multicystic MA. A 21-year-old woman without any stigmata of neurofibromatosis type 2 presented with intractable seizures since 10 years. Brain magnetic resonance imaging revealed a well-defined, multicystic mass with heterogeneous signal intensity in the right temporal lobe. The patient underwent resection of the lesion and of the epileptogenic cortex under intraoperative electrocorticography (ECoG) assistance. Histopathological examination showed proliferation of perivascular cells that were arranged in a cuff pattern and were positive for vimentin, D2-40 and smooth muscle actin. Mutiple microcysts and enlarged perivascular spaces were present, which was similar to the structure of the arachnoid cavity. Hyalinized collagen fibers with round concentric acellular eosinophilic lamellae within areas of reactive gliosis were noted for the first time in MA. The patient was followed up without any clinical symptoms or recurrence for 2 years.

Conclusion

MA may originate from arachnoid and vascular tissue trapped in the cortical parenchyma during brain development, and the cysts may have resulted from the gradual accumulation of cerebrospinal fluid in the perivascular spaces of the trapped tissue. Resection of the lesion and of the epileptogenic cortex is important not only for pathological diagnosis but also for seizure control, and intraoperative ECoG assistance is recommended.

Sporadic meningioangiomatosis: imaging findings with histopathologic correlations in seven patients

INTRODUCTION

Meningioangiomatosis (MA) is a rare benign cerebral lesion. We aimed to evaluate the CT and MR features of sporadic MA, with a focus on the correlation between imaging and histopathologic findings.

METHODS

CT (n = 7) and MR (n = 8) images of eight patients (6 men and 2 women; mean age, 12.8 years; range, 4-22 years) with pathologically proven MA were retrospectively reviewed. After dividing the MA lesions according to their distribution into cortical and subcortical white matter components, the morphologic characteristics were analyzed and correlated with histopathologic findings in seven patients.

RESULTS

CT and MR images showed cortical (n = 4, 50%) and subcortical white matter (n = 7, 88%) components of MA. All four cortical components revealed hyperattenuation on CT scan and T1 isointensity/T2 hypointensity on MR images, whereas subcortical white matter components showed hypoattenuation on CT scan and T1 hypointensity/T2 hyperintensity on MR images. Two cortical components (25%) demonstrated enhancement and one subcortical white matter component demonstrated cystic change. Seven cases were available for imaging-histopathologic correlation. In all seven cases, the cortex was involved by MA and six patients (86%) showed subcortical white matter involvement by MA. There were excellent correlations between the imaging and histopathologic findings in subcortical white matter components, and the accuracy was 100% (seven of seven); whereas there were poor correlations in cortical components, and the accuracy was 43% (three of seven).

CONCLUSIONS

The cerebral cortex and subcortical white matter were concomitantly involved by MA. Subcortical white matter components of MA were more apparent than cortical components on CT and MR imaging.

Focal epileptogenic lesions

The spectrum of focal epileptogenic lesions and their clinical manifestations in children differ substantially from those seen in adults. In adults, mesial temporal sclerosis is the common lesion in surgical series; but in children, MTS is uncommon, and when it does occur, it exists frequently as dual pathology. The most common lesions in pediatric epilepsy surgery candidates are malformations of cortical development, developmental tumors, or encephalomalacia from infarction, hypoxia, trauma, or infection. Careful analysis of the lesion characteristics on brain MRI is sufficiently predictive of pathology in most cases. Histopathological evaluation remains the gold standard for diagnosis of mass lesions. The electroclinical phenotype of epilepsy in adults is largely determined by the anatomical location of the lesion and its connectivity. In children, in addition to the location of the lesion, the age at onset of the lesion and the age at onset of epilepsy have a major impact on the electroclinical phenotype. Children with congenital or early acquired lesions may manifest with generalized features on EEG and seizure semiology. Experience from various centers has demonstrated that a subset of these children benefit from epilepsy surgery despite a generalized epilepsy phenotype. All children with medically refractory epilepsy and a focal lesion should undergo evaluation for potential epilepsy surgery irrespective of the EEG findings and seizure semiology.

Multifocal meningioangiomatosis in a 3-year-old patient

Meningioangiomatosis consists of benign hamartomatous lesions of the brain and the leptomeninges, which typically present with seizure. Management is predicated on resection and control of seizures with medication. Lesions are typically solitary. Multifocal meningioangiomatosis is extremely rare, with only 2 cases reported in adults and none in children. The authors report the first case, to their knowledge, of multifocal meningioangiomatosis in a child. This unique case highlights therapeutic challenges associated with these lesions and demonstrates that multifocality is possible in the pediatric population. This finding has implications for diagnosis and follow-up for children afflicted with these tumors.

Meningioangiomatosis Without Neurofibromatosis Type 2

Meningioangiomatosis (MA) is a rare, benign hamartomatous lesion found in cerebral cortex and leptomeninges. It occurs mostly in 5 - 15 year old children in form isolated or diffuse; the diffuse form may be associated with neurofibromatosis type 2 (NF2). The sporadic type in the adults is less common.The patient was a 37 year-old man with a long history of frontal headache. In suspected sinusitis, the patient underwent cerebral MRI that showed hypointense lesion in the right frontal lobe with heterogeneous contrast enhancement after gadolinium administration. There were no stigmata or family history of neurofibromatosis. A right pterional approach with a supraorbital craniotomy was performed. The lesion was removed with complete remission of the headache in the postoperative time. MA enters into differential diagnosis with several other diseases and a correct diagnosis is mandatory. The total surgical removal is the treatment of choice, and the prognosis after surgery is usually excellent for the absence of recurrence in sporadic cases.

Meningioangiomatosis without neurofibromatosis simulating encephalitis in neuroimaging

Background:

Meningioangiomatosis (MA) is a rare entity characterized by a focal lesion that affects the leptomeninges and the cerebral cortex.

Case Description:

We describe a case of a 32-year-old man diagnosed with MA not associated with hamartomatous lesions or with type 2 neurofibromatosis. Magnetic resonance images (MRI) showed an extensive parieto-occipital lesion and another right frontal lesion, initially suggestive of encephalitis. A biopsy of the meninges and brain was performed via a right parieto-occipital craniotomy. The histopathologic diagnosis, complemented by immunohistochemical studies, was MA.

Conclusion:

Diagnosis of MA is very difficult based only on images, therefore lesions compromising the brain cortex, associated or not with calcifications, should be further examined through biopsy so as to have a precise diagnosis.

Neuropathology of temporal lobe epilepsy

Pathologic findings in surgical resections from patients with temporal lobe epilepsy include a wide range of diagnostic possibilities that can be categorized into different groups on the basis of etiology. This paper outlines the various pathologic entities described in temporal lobe epilepsy, including some newly recognized epilepsy-associated tumors, and briefly touch on the recent classification of focal cortical dysplasia. This classification takes into account coexistent pathologic lesions in focal cortical dysplasia.

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.

Focal leptomeningeal enhancement and corticopial calcifications underlying a parietal convexity lipoma: a rare association of findings in 2 pediatric epileptic patients

We present the unusual neuroimaging findings of focal cerebral leptomeningeal enhancement in association with corticopial calcifications, underlying a parietal convexity lipoma in 2 pediatric patients with normal psychomotor development, unremarkable physical findings, and recent onset of epilepsy. To our knowledge, this clinical and neuroradiological association has not been previously reported and shows overlapping features with Sturge-Weber syndrome without facial nevus and encephalocraniocutaneous lipomatosis, thus possibly representing an extremely rare variant within the spectrum of these congenital neurocutaneous disorders.

Tuberculosis: an extremely unusual cause of orbital wall erosion

We present the case report of a 10-year-old girl who presented to us with a painless swelling involving the left infraorbital region. The swelling was diagnosed to be tubercular in origin with erosion of the zygomatic, maxillary and frontal bones constituting the inferior and lateral walls of the left orbit. The patient responded well to antitubercular chemotherapy. A discussion of the case and a literature review of causes of orbital erosion is presented.

Meningioangiomatosis in a 5-year-old boy presenting with intractable seizures

A 5-year-old boy with a history of epilepsy underwent brain magnetic resonance imaging (MRI) because of an increase in seizure frequency. Brain MRI demonstrated a left frontal lesion. The patient was operated upon, and gross total excision was performed. The histological diagnosis was meningioangiomatosis. On follow-up examination 10 years later, the patient was free of seizures and without any evidence of tumor recurrence. Meningioangiomatosis is a rare benign hamartomatous lesion that is associated with seizures. Complete excision is associated with favorable long-term outcome. The novelty of the present case is the young age of the child at presentation and the curative role of surgery considering the long-term follow-up.

Imaging diagnosis--Canine meningioangiomatosis

Meningioangiomatosis is a rare proliferative disorder of the central nervous system. It occurs sporadically in dogs and is characterized by a leptomeningeal plaque that extends from the subarachnoid space along the perivascular spaces into the adjacent parenchyma. We describe the clinical presentation, magnetic resonance (MR) imaging and neuropathologic characteristics of two additional dogs with meningioangiomatosis, and document involvement of the thoracolumbar spinal cord, a site not previously described for this condition. MR imaging findings were different from those previously described, most likely reflecting the degree of vascularity and collagen deposition. The MR imaging features of meningioangiomatosis are not specific.

Pseudoneoplasms of the Nervous System

Context.—Pseudoneoplasms of the nervous system vary greatly in nature. Ranging from inflammatory to autoimmune, infectious, malformative, reactive, degenerative, and radiation induced, they all mimic true tumors. Thus, they have the potential to mislead clinicians, radiologists, and pathologists alike. Their clinical and/or neuroimaging and histologic features are readily misinterpreted as tumor. Knowledge of the pitfalls is essential to avoid mismanagement, specifically overtreatment. In such instances, pathologists must take the entire clinical picture into consideration, acquainting themselves with presenting symptoms, physical findings, and neuroimaging.

Objective.—To present 10 examples of pseudoneoplasms of the nervous system, analyze the basis for their mimicry, and discuss their differential diagnosis.

Data Sources.—Review of the pertinent literature related to pseudoneoplasms of the nervous system and review of the consultation files of one of the authors (B.W.S.).

Conclusions.—The identification of tumor mimics may be difficult under the best of circumstances, and maintaining a broad differential diagnosis as well as application of a variety of immunocytochemical and occasionally ultrastructural and/or molecular genetic methods is essential to arrive at a correct diagnosis.

Computed tomography and magnetic resonance appearance of sporadic meningioangiomatosis correlated with pathological findings

PURPOSE

Meningioangiomatosis (MA) is a rare benign localized lesion of leptomeninges and underlying cerebral cortex. Preoperative diagnosis is difficult and challenging because of its diverse clinical, pathological, and imaging features. We retrospectively analyzed 7 cases of MA to explore their imaging features and correlate with pathological findings.

MATERIALS AND METHODS

Imaging studies including computed tomography (CT) and magnetic resonance imaging (MRI) were retrospectively reviewed in 7 patients with surgically and pathologically verified intracranial MA (not associated with neurofibromatosis). Computed tomography studies were performed in axial plane without iodinated contrast-material administration; magnetic resonance studies consisted of axial T1-weighted, T2-weighted, Fluid attenuated Inversion Recovery (FLAIR), and postcontrast T1-weighted sequences and coronal or sagittal precontrast and postcontrast T1-weighted sequences.

RESULTS

Computed tomography showed focal extensively calcified lesions in 3 cases, lesions with patchy calcification in 2 cases, and no apparent calcification in 2 cases. Magnetic resonance imaging demonstrated predominantly hypointensity on T1-weighted images and hyperintensity on T2-weighted images. Six of 7 cases exhibited gyriform hyperintensity on FLAIR sequences, which correlated with proliferating microvessels with perivascular cuffs of spindle-cell proliferation within the cortex on histopathological analysis. After contrast-material administration, all but 1 showed heterogeneous enhancement. The nonenhancing lesion on MRI was completely calcified on CT.

CONCLUSION

Gyriform hyperintensity on FLAIR sequence is the main MRI feature of MA, which correlates with proliferating microvessels with perivascular cuffs of spindle-cell proliferation within the cortex on pathological analysis. Plain CT scan is essential to demonstrate the extent of calcification of these lesions.

Imaging and spectroscopic findings in meningioangiomatosis

Meningioangiomatosis (MA) is an uncommon brain tumor. The role of imaging techniques is underscored in cases where the tumor location makes resection (or even biopsy) dangerous. We report the case of a child with an MA tumor located deep in the right sylvian fissure. A computed tomography (CT) scan showed calcifications in a highly vascular lesion with surrounding edema. Magnetic resonance spectroscopy (MRS) showed a distinct choline (Cho) peak, which usually suggests a proliferating tumor. Fluorodeoxyglucose positron emission tomography (FDG-PET) showed the lesion lacked hypermetabolic features. These radiological features should put MA in the differential diagnosis.

A case of infantile meningioangiomatosis with a separate cyst

Meningioangiomatosis (MA) is a rare congenital tumor that occurs mostly in 5-15 year old children. There have been only 5 cases previously reported that described the cystic nature within these tumors. We present a case of a MA accompanied by a separate macrocyst. A normally developed 2 year-old female patient presented with partial and generalized seizures. The brain computerized tomogram and magnetic resonance imaging revealed the presence of a calcified mass accompanied by a cyst in the right parietal area, surrounded by low density and high attenuation edema and hemorrhage. Upon right parietal craniotomy, a 1.6 cm x 1.2 cm x 0.5 cm sized plate-like, gray-white, slightly hard mass was seen and it was completely excised. Approximately 1 cm from the mass in the anterior lateral direction, a cyst was found and subsequent biopsy of the cyst wall revealed no tumor tissue, and therefore the cyst was not removed. Pathologic report demonstrated the meningioangiomatosis. Follow up examination 2 years later showed no recurrence of the tumor, and there was no evidence of neurological deficits. Authors suggest that cysts that arise in the surrounding tissues of tumors may not be tumor cysts, and do not require surgical removal.

Imaging surgical epilepsy in children

INTRODUCTION

Epilepsy surgery rests heavily upon magnetic resonance imaging (MRI). Technical developments have brought significantly improved efficacy of MR imaging in detecting and assessing surgical epileptogenic lesions, while more clinical experience has brought better definition of the pathological groups.

DISCUSSION

MRI is fairly efficient in identifying developmental, epilepsy-associated tumors such as ganglioglioma (with its variants gangliocytoma and desmoplastic infantile ganglioglioma), the complex, simple and nonspecific forms of dysembryoplastic neuroepithelial tumor, and the rare pleomorphic xanthoastrocytoma. The efficacy of MR imaging is not as good for the diagnosis of focal cortical dysplasia (FCD), as it does not necessarily correlate with histopathological FCD subtypes and does not show the real extent of the dysplasia which may even be missed in a high percentage of cases. Further developments with better, multichannel coils, higher magnetic fields, specific sequences, and different approaches (such as diffusion tensor imaging) for depicting the structural abnormalities may hopefully improve this efficacy. A general review of the MR features of the diverse pathologies concerned with epilepsy surgery in the pediatric context is provided with illustrative images.

Meningioangiomatosis associated with neurofibromatosis: report of 2 cases in a single family and review of the literature

BACKGROUND

Meningioangiomatosis (MA) is a rare benign disorder. It may occur sporadically or in association with neurofibromatosis (NF). The sporadic type typically presents with seizures, whereas that associated with NF is often asymptomatic. Of the 100 cases reported, only 14 are associated with NF. We now report 2 additional cases of MA associated with neurofibromatosis 2 (NF2) in a single family, with one occurring in the cerebellum. The etiology, pathology, and imaging features of MA are presented.

CASE DESCRIPTION

A 38-year-old woman (patient 1) presented with a 4-month history of ataxia. She had been diagnosed previously with NF2. Magnetic resonance imaging (MRI) scans of the brain revealed bilateral acoustic neuromas and multiple calcified intracranial lesions. Her 13-year-old daughter (patient 2) presented with complex partial seizures. MRI scans of the brain revealed bilateral acoustic neuromas and a right parietal mass. Patient 1 underwent a suboccipital craniotomy to resect the right-sided acoustic neuroma. A small portion of normal-appearing cerebellar cortex was resected to avoid undue retraction. Histopathologic examination showed the presence of a lesion consistent with MA. Patient 2 underwent a right temporal-parietal craniotomy to remove the enhancing epileptogenic right posterior temporoparietal lesion. Histopathologic analysis showed a lesion consistent with meningioma and MA.

CONCLUSIONS

MA has been reported infrequently in association with NF2. We now report 2 cases of MA associated with NF2 in one family, and we add the cerebellum to possible locations of occurrence. MA should be considered in the differential diagnosis of cortical lesions, particularly in patients with NF2.

Histopathological study of five cases with sporadic meningioangiomatosis

We report five cases of sporadic meningioangiomatosis, three males and two females, ranging in age from 12 to 36 years at diagnosis. The lesion was found incidentally by MRI after a head trauma in one case; the other four subjects had a seizure disorders, which improved following surgical resection of the cortical lesions. Grossly, the lesionectomy specimens were of a whitish color and firm consistency. Histological examination revealed that the lesions were confined to the cortex with focal involvement of the overlying leptomeninges, and revealed unifying features of meningioangiomatosis, such as proliferating microvessels with perivascular cuffs of spindle-cell proliferation within the cortex. Two cases had numerous calcifications; one was associated with a prominent fibrocalcifying component. Immunostaining results were variable among the cases. Only vimentin was consistently positive. Some of the spindle cells were weak positive for EMA in two cases. Immunoreactions with anti-CD34 detected within the cytoplasm of the spindle cells were observed in three of the five cases. The Ki-67 proliferation index of all the cases was very low, less than 0.1%. Neurofibrillary tangles were identified in only one of the five cases using the Bodian and immunostaining methods. These findings indicate that meningioangiomatosis lesions show a wide range of clinicopathological features, making diagnosis difficult. A histopathological spectrum and differential diagnoses were discussed with a review of the literature. Since this lesion is a distinct clinicopathological entity and hamartomatous in nature, it is important to make a correct diagnosis in order to avoid further aggressive treatment.