Extra-Axial Cystic Meningioma without Dural Attachment in an Adult: Case Report and Review of Literature

Intraparenchymal meningiomas, meningiomas without dural attachment, and cystic meningioma are atypical and extremely rare, especially in adults. Only four cases of intraparenchymal cystic meningioma without dural attachment have been reported. A 47-year-old female presented with an altered sensorium. She had a progressive bifrontal headache for 2 months. Computed tomography scan of the brain showed an 8 cm × 6 cm cystic lesion with a solid component in the left frontoparietal region with a midline shift. The solid part of the lesion was enhancing on contrast but the cyst rim was not. Intraoperatively, the cyst was filled with amber-colored fluid, which was drained, and the solid component was completely excised. Histopathological examination of the solid tumor component confirmed cystic meningioma. At 2 years of follow-up, she has no evidence of recurrence. We report the fifth case of this very rare entity and review the literature.

Intraparenchymal Meningioma

Meningiomas have been described as the most frequent extra-axial tumor in the brain. Most are benign and correspond to World Health Organization (WHO) grade I; however, there are some reports of cases that shows atypical locations, like subcortical intra-axial meningiomas. This represents a challenge in radiological diagnosis because it could be taken as a metastasis tumor or vascular malformations. The authors bring a case report of a previously healthy patient who presents a traumatic brain injury with no traumatic lesions. A computed tomography (CT) evidenced a left frontal rounded subcortical lesion surrounded by large vasogenic edema. The first diagnostic impression was a metastasis tumor. During surgery, a total resection was completed, and the appearance of the tumor was meningioma. This was later confirmed by histological analysis. The literature was reviewed in order to determine the importance of including intraparenchymal meningiomas in the differential diagnosis of intracranial lesions.

Primary Intraparenchymal Meningiomas: A Case Report and a Systematic Review

BACKGROUND

Primary intraparenchymal meningiomas are exceedingly rare and often challenging to diagnose, given their misleading radiologic features. It is hypothesized that they arise from the cap cells of the pia mater that enter the brain via penetrating blood vessels during brain development. We systematically reviewed and analyzed previously reported features of primary intraparenchymal meningiomas in terms of radiography, presenting symptoms, and histopathology.

METHODS

A literature search of the Web of Science and PubMed databases and crossed references was performed in March 2021, per PRISMA guidelines, with no restrictions regarding publication date. Data regarding demographic features, clinical, radiographic, and histopathologic characteristics were extracted.

RESULTS

A total of 52 patients (including the reported case) were included in this review. The mean age was 21.1 years (range, 0.3-66 years) with a male/female ratio of 1.9:1. The most common localizations of intraparenchymal meningiomas were in the frontal (30.8%) and temporal (21.2%) lobes. Cyst formation was more readily observed and was noted in 51.4% of patients. Histopathology showed a higher incidence of World Health Organization grade II (14/52, 26.9%) and World Health Organization grade III (7/52, 13.5%) of primary intraparenchymal meningiomas.

CONCLUSIONS

We present a comprehensive analysis of every reported primary intraparenchymal meningioma. Because of their rarity and capacity to mimic other more common intra-axial tumors, they represent a diagnostic challenge. This systematic review highlights the importance of paying attention to atypical intra-axial lesions, with a particular reflection on the discrepancy between clinical characteristics and imaging features.

Giant Intraparenchymal Meningioma in a Female Child: Case Report and Literature Review

BACKGROUND

Intraparenchymal meningiomas without dural attachment are extremely rare, especially in female children. To our knowledge, fibrous intraparenchymal meningioma located in the temporal lobe has never been reported in female children. The significance in the differential diagnosis of lesions in the temporal lobe should be emphasized.

CASE PRESENTATION

A 12-year-old girl was admitted to our hospital, complaining of recurrent generalized seizures for 2 months. Magnetic resonance imaging demonstrated a solid lesion located in the temporal lobe. The lesion underwent gross total resection. Histopathological examination indicated that the lesion was a fibrous meningioma. Postoperative rehabilitation was uneventful.

CONCLUSION

This case report presents an extremely unusual intraparenchymal fibrous meningioma of the temporal lobe with peritumoral edema and reviewed 21 intraparenchymal meningioma cases in children and to discuss the clinical presentation and treatment, differential diagnosis, and radiological features.

Sylvian Fissure Meningioma in Childhood: Report of 3 Cases and Review of the Literature

OBJECTIVE

Sylvian fissure-based meningioma is a rare occurrence during childhood. We report a small series including 3 such cases, all attached to the arachnoid leaflets of the Sylvian fissure. We present a review of the literature and discuss the impact of possibly effective clinical, imaging, and surgical variables on the outcome.

METHODS

In a retrospective chart review of children with intracranial meningioma, we encountered 3 cases with Sylvian fissure meningioma operated within the past 32 years.

RESULTS

Two girls, 5 and 7 years old, and 1 boy, 7 years of age, presented with epilepsy, headache, diplopia, and hemiparesis. The duration of illness was 3, 4, and 2 months, respectively. All three tumors were attached to the arachnoid layer of the adjacent Sylvian fissure, and they were not dural based. Gross total resection could be achieved, and no recurrences were encountered after 13, 7, and 2 years.

CONCLUSION

We report 3 very rare cases of Sylvian arachnoid-based meningiomas. To our knowledge, this is the study with the longest follow-up period (mean 7.3 years, median 7 years). Even though the overall prognosis of pediatric meningiomas may be worse than that of adult illness, we would like to emphasize that the "rare location" of the Sylvian fissure was not an important factor contributing to the outcome in our children.

Intraparenchymal Atypical Meningioma in Basal Ganglia Region in a Child: Case Report and Literature Review

Intraparenchymal meningiomas without dural attachment are extremely rare, especially when they occur in basal ganglia region in child. An 8-year-old boy was admitted at our hospital, complaining of recurrent headache and vomiting for 3 months. Neurological examination showed impaired vision and mild paresis of the left extremities. Magnetic resonance imaging demonstrated a lesion located in the right basal ganglia region extending to superasellar cistern with solid, multiple cystic and necrotic components. Computed tomography revealed calcification within the mass. Due to the anterior cerebral artery involvement, a subtotal resection was achieved and postoperative radiotherapy was recommended. Histopathological examination indicated that the lesion was an atypical meningioma. The postoperative rehabilitation was uneventful. Mildly impaired vision and motor weakness of left extremities improved significantly and the patient returned to normal life after surgery. To our knowledge, intraparenchymal atypical meningioma in basal ganglia extending to superasellar cistern was never reported. The significance in differential diagnosis of lesions in basal ganglia should be emphasized.

Sporadic pediatric meningiomas: a neuroradiological and neuropathological study of 15 cases

OBJECTIVE Sporadic meningiomas have been classified in many different ways. Radiographically, these lesions can be described as occurring in either typical or atypical locations. The purpose of this study was to determine if there are any histopathological differences between sporadic meningiomas that arise in these varying locations in children. METHODS The neuroimaging, histopathological findings, and clinical records in patients with sporadic pediatric meningiomas not associated with neurofibromatosis Type 2 or prior radiation therapy were retrospectively reviewed. Tumors were classified by radiological findings as either typical or atypical, and they were categorized histopathologically by using the latest WHO nomenclature and grading criteria. RESULTS Fifteen sporadic meningiomas in pediatric patients were biopsied or resected at the authors' institution between 1989 and 2013. Five (33%) were typical in radiographic appearance and/or location and 10 (67%) were atypical. Four (80%) typical meningiomas were WHO Grade I tumors. Most (60%) of the atypical meningiomas were WHO Grade II or III. CONCLUSIONS This study is the largest series of sporadic pediatric meningiomas in atypical locations to date. Although sporadic meningiomas are relatively infrequent in children, those with atypical imaging, specifically those with apparently intraparenchymal and intraosseous locations, may be more common than previously recognized. In this study, pediatric sporadic meningiomas arising in atypical locations, in particular intraparenchymal meningiomas, may be of higher histopathological grade. The authors' findings should alert clinicians to the potential for more aggressive clinical behavior in these tumors.

Rare Parenchyma Meningioma in an Adolescent Female With Cheek Tingling: A Case Report

The following is a report on a rare parenchyma meningioma and the computed tomography (CT) and magnetic resonance imaging (MRI) findings. To our knowledge, this was the first characterization of magnetic resonance spectroscopy (MRS) in a parenchyma meningioma. Three days after initial presentation, a 14-year-old female student reported feeling tingling in her cheek, grading 3 to 4 points. Two hours later, the tingling had disappeared. The patient was admitted to hospital with stable vital signs and no abnormal presentations upon physical examination. A routine CT scan of the brain showed a quasicircular region of the left occipital lobe was homogenous hyperdense and an arcualia calcification was found on the lesion's margin and the boundary was ill-defined. Further MRI and contrast-enhanced scanning of the brain showed that a lobulated nidus with abnormal signaling was present in the left occipital lobe and was approximately 1.9 × 2.0 cm. Hypointensity on T1-weighted imaging and a slight hyperintensity on T2-weighted imaging was also observed. A short T2 signal appeared on the margin and a few longer T2 edema zones appeared around the nidus, whereas the lesion showed homogenous enhancement. MRS was characterized by a slight or moderate increase of a choline (Cho) peak and a small reduction of the N-acetyl aspartate (NAA) peak. After completing the preoperative preparation, the excision of the supratentorial deep lesions was performed on the patient. The pathology led to a diagnosis of a left occipital lobe meningioma, WHO I. The patient was followed-up for 14 months postoperation, and had no reoccurrences. Intraparenchymal meningioma rarely occurs in brain parenchyma, and is characterized by lesions with abundant blood supply and requires a glioma to be identified. MRS is a potential tool for preoperative diagnosis of intraparenchymal meningioma.

Pediatric Intraparenchymal Meningioma: Case Report and Comparative Review

Intra-axial (intraparenchymal) meningiomas are an extremely rare pathology with only dozens of cases reported. In children, the unusual characteristics of intraparenchymal meningiomas can easily create an atypical preoperative differential. The authors present the case of an otherwise healthy 14-year-old girl presenting with new-onset seizures and an intracranial lesion upon investigation. CT and MRI revealed a lesion both cystic and calcified in nature, residing completely within the brain parenchyma. Upon operative examination, the mass was found to be completely surrounded by cortex and to be of two disparate consistencies. Pathological analysis revealed the mass to be a meningioma. Despite the rarity in children, meningiomas must be kept on the differential for cystic, calcified lesions. The differential diagnosis based on imaging as well as the operative strategy taken are further discussed. In addition, the authors review the current understanding of pediatric meningiomas as compared with adult meningiomas.

Intraparenchymal meningioma mimicking cavernous malformation: a case report and review of the literature

Introduction

A primary intraparenchymal meningioma located in the subcortical region of the brain without a dural attachment is extremely rare. To the best of our knowledge, this is the first report showing that meningioma can mimic cavernous malformations.

Case presentation

We present the case of a 42-year-old German man who presented to our institution with seizure. Both computed tomography and magnetic resonance imaging scans showed characters of an intra-axial subcortical lesion with a ‘popcorn’ appearance and hemosiderin deposits in the right parietal lobe. The initial diagnosis was cavernous malformation. Intraoperatively, the lesion presented as a subcortical mass that had no connection to the dura or the ventricle. The histological diagnosis showed a WHO Grade 1 ‘raddled’ psammomatous meningioma with extensive metaplastic ossification. A literature review of 29 cases of intraparenchymal meningiomas regarding their clinical presentations, location and management was performed.

Conclusions

Meningiomas can be found in any region of the brain with and without dural attachment. Intraparenchymal meningiomas can have multiple entities mimicking their presentation. Caution must be used regarding the preoperative differential diagnosis.