Intraventricular meningiomas: a clinicopathological study and review of the literature

Abstract

<jats:sec> <jats:title>Object</jats:title> <jats:p>Intraventricular meningiomas are rare tumors. The origin of these tumors can be traced to embryological invagination of arachnoid cells into the choroid plexus. The authors analyzed data that they had collected to study the clinicopathological aspects and review the origin, presentation, imaging, and management of these tumors.</jats:p></jats:sec> <jats:sec> <jats:title>Methods</jats:title> <jats:p>In this retrospective analysis, the authors describe the cases of 12 patients who had received a diagnosis of intraventricular meningioma and underwent surgery for the tumors. Nine of these patients were men and three were women. Features of neurofibromatosis Type 2 were present in two of the women. Nine of the tumors were located in the lateral ventricles, one was in the third ventricle, and two were in the fourth ventricle. Raised intracranial pressure (ICP) was the universal presentation in all the patients, and the preoperative diagnoses were confirmed on neuroimaging studies. Excision was performed using the parietooccipital (trigonal) approach for lateral ventricle tumors, the transcortical–transventricular route for the third ventricle tumor, and suboccipital craniectomy for fourth ventricle tumors. Postoperatively, one patient died and the others experienced resolution of their symptoms. Histopathological features of these tumors were similar to those seen in meningiomas in other locations.</jats:p></jats:sec> <jats:sec> <jats:title>Conclusions</jats:title> <jats:p>Intraventricular meningiomas are slow-growing tumors that become large prior to detection. Although they are commonly seen in the lateral ventricles, they occur in the third and fourth ventricles as well. Presentation is in the form of raised ICP with no localizing features; therefore the diagnosis is based on imaging studies. Hydrocephalus occurs due to obstruction of cerebrospinal fluid pathways. Excision requires planning to avoid eloquent cortex incision. The histopathological features are varied, although most of the tumors in the study were angiomatous meningiomas. These tumors are no different histologically from tumors that are dural in origin. No recurrence has been reported.</jats:p></jats:sec>

Third Ventricular Meningioma -Case Report-

“…Third ventricle tumors are supplied by medial posterior choroidal vessels, whereas fourth ventricle tumors are supplied by choroidal branches of the posterior inferior cerebellar artery. 2,9) Tumor staining was faint in this case. Soluble interleukin-2 receptor level in the cerebrospinal fluid was within normal limits in this case.…”

“…Visual field deficits may be seen in 25% of patients and seizures are rare. 2) Hypothalamic features with or without endocrinopathy may be seen in third ventricle tumors. Manifestations of NF 2 may be evident on clinical and neurological evaluation.…”

“…4) Arachnoid tissue is transported together with the choroid plexus as the ventricular system invaginates, and by 20 to 40 weeks, the central stroma of the choroid plexus contains meningocytes, connective tissues, and blood vessels. 2,14) Meningiomas arise from arachnoid cap cells, which are specialized cells in arachnoid granulations. Similarly, intraventricular meningiomas arise from arachnoid cells contained within the choroid plexus.…”

“…Total removal of third ventricle meningiomas can be achieved through the interhemispheric transcallosal, interhemispheric trans-lamina terminalis, or transcortical-transventricular approaches. [1][2][3]11,13,15,17,18) The transcorticaltransventricular approach requires cortical incision to reach the lateral ventricle. This approach is best used for lesions with a significant intraventricular component within the third ventricle and associated enlarged lateral ventricles.…”

“…Intraventricular meningiomas are rare tumors, accounting for 0.5% to 5% of all intracranial meningiomas. 2) Although some series have reported lateral ventricle meningiomas, there are few case reports of third and fourth ventricle meningiomas. We present our experience with a case of third ventricle meningioma.…”