Case presentation

  1. Case 1—

    A 12-year-old boy presented to the department of neurosurgery with headache and vomiting for 4 months and recent onset of giddiness since 2 months. On examination, the child did not have any motor or sensory deficit. Fundus examination showed papilledema in both the eyes. The computed tomography (CT) brain revealed a large nodular, hyperdense, uniformly enhancing lesion occupying both the lateral ventricles (right more than left) and third ventricle with resultant ventricular dilatation (Fig. 1). On magnetic resonance imaging (MRI), the lesion appeared isointense on T1, mildly hypointense on T2 (Fig. 2), and showed uniform enhancement on contrast administration (Fig. 3). This appeared to be primarily intraventricular arising from the right lateral ventricle and then involving the third as well as the left lateral ventricle. In view of the nodularity, the child was taken up for an endoscopic biopsy of the lesion. The lesion appeared fibrous and biopsy did not reveal any malignancy. CSF was also negative for abnormal cells and tumor markers. Three days later, the child underwent surgical excision. A bicoronal scalp flap was raised and a right frontal craniotomy was performed. A transcortical approach through the middle frontal gyrus was used and gross total excision of the lesion was achieved. The tumor was moderately vascular and of variable consistency being soft in the center and firm on the outer side of all nodules (Fig. 4). The tumor could be dissected easily from the ventricular wall as well as from its attachment to the tela choroidea. Frozen section confirmed a meningioma encouraging complete excision. Postoperative CT scan showed complete excision (Fig. 5). Transitional type of meningioma was further confirmed on histopathology evaluation with a MIB Index of 2%. Postoperative period was uneventful except for a small subdural collection which settled after two tappings.

  2. Case 2—

    A 3-year-old boy presented with imbalance on walking since 6 months. He had features of raised intracranial pressure with headache and vomiting since 2 weeks. He had an ataxic gait and bilateral papilledema on examination. General examination was normal. The MRI scan showed a lobulated lesion in the left lateral ventricle which was isointense on T1 and T2. The lesion had homogeneous contrast enhancement (Fig. 6). The child underwent left frontal craniotomy and transcortical approach was used with gross total excision of the lesion (Fig. 7). Frozen section as well as final histopathology report confirmed a transitional meningioma (WHO grade I). The child developed bilateral subdural hygromas and underwent subduro-peritoneal shunt after observation for a month with complete resolution of symptoms. However, 6 months later, the child developed hydrocephalus and needed insertion of a left ventriculo-peritoneal shunt and removal of subdural shunt. At 2 years follow-up, the child complained of loss of vision and developed weakness in all four limbs. On evaluation, he was found to have several nodular lesions in the CV junction, cervical spine, and other stigmata of neurofibromatosis type II (Fig. 8). Decompression was done by removing the largest lesion. He has recovered well except in terms of vision and is under follow-up of more than 3 years.

Fig. 1
figure 1

CT scan (plain) showing a nodular, hyperdense, intraventricular lesion (arrow) with hydrocephalus

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Fig. 2
figure 2

Iso- to hyper-intense lesion (arrow) seen on T2 weighted MRI

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Fig. 3
figure 3

Postcontrast axial, coronal, and sagittal MRI sections showing intense homogeneous enhancement of the lesion

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Fig. 4
figure 4

Intra operative image showing the nodular tumor (blue arrow) dissected from the anterior choroidal artery (green arrow)

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Fig. 5
figure 5

Postoperative CT scan showing complete excision of lesion

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Fig. 6
figure 6

Axial, coronal and sagittal post contrast MRI showing a well-defined, lobulated, homogenously enhancing lesion predominantly in the left lateral ventricle (arrow)

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Fig. 7
figure 7

Postoperative CT scan showing complete excision of lesion

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Fig. 8
figure 8

Follow up MRI scan after 2 years showing intensely enhancing lesion at C4/5 level (green arrow) and also at the cranio-vertebral junction (red arrow)

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Introduction

Meningiomas are common brain tumors in adults, but occur very rarely in children. An intraventricular location sans dural attachment is unusual but has been reported in the past. Inside the ventricles, they arise from the arachnoid cells present within the choroid plexus, tela of the velum interpositum, and tela choroidea [1, 2]. Meningiomas account for less than 3% of brain tumors in children with intraventricular location constituting about 0.5 to 5% among them [3]. Management of these tumors is difficult owing to the depth of tumor, young age involved, large size of the lesion at presentation, increased vascularity, and absence of any neurological deficit which can add to the diagnostic difficulty.

Discussion

Meningiomas in children form a minority of cases as compared to a much higher incidence in adults. Conversely, the ratio of incidence of intraventricular meningiomas to intracranial tumors is higher in children than in adults [4]. In children, they tend to occur between 5 and 15 years of age [5]. As compared to their adult counterparts, pediatric meningiomas tend to have a higher grade on presentation and a more aggressive course [6]. Magnetic resonance imaging with contrast administration is preferred for diagnosis. They are iso- to hypointense on T1 and T2WI but show intense enhancement on contrast administration. This helps to delineate the tumor and plan the surgical approach [7]. Remotely, they may be associated with cystic change. The radiological presentation in children is similar to that in adults except for the larger size of tumor seen in the pediatric age group [7]. Meningiomas inside the ventricles are slow-growing tumors that tend to become large prior to detection. The plausible hypothesis is the presence of a large space in the ventricles which allows for tumor expansion especially in the lateral ventricles. Owing to the large space within, the lateral ventricle is the commonest site of tumor noted followed by the third and fourth ventricle. Until the outflow channels are obstructed mechanically, signs and symptoms are mild and nonspecific. The usual presentation is with symptoms of raised intracranial pressure. The intraventricular location makes neurological examination and localization difficult due to the paucity of deficits. The fourth ventricular and third ventricular tumors may present with cerebellar signs and hypothalamic disturbances. Although the overall incidence of seizures is lesser in children than in adults, few patients may still present with generalized tonic clonic variant of seizures. Cushing and Eisenhardt [8] described the following five characteristic clinical features of lateral ventricle meningiomas:

  1. (a)

    Pressure symptoms often in the form of unilateral headache

  2. (b)

    Contralateral homonymous macular splitting hemianopia

  3. (c)

    Contralateral sensorimotor deficit (sensory involvement greater than motor involvement)

  4. (d)

    Cerebellar affection in more than half the cases

  5. (e)

    Dysphasic and paralexic disturbance in left-sided tumors

The peculiar deep location with possible attachments and hidden vascular pedicles makes it a challenging prospect to manage surgically. An endoscopic biopsy of these lesions may help in confirming the diagnosis and helps to plan further surgical approach but it is unlikely to help as a cerebrospinal fluid diversion technique. The definitive treatment remains surgery and total excision of the tumor is curative since the lesion is benign in nature. The possible differentials to be ruled out are choroid plexus papilloma, ependymoma, and astrocytoma. The extent of surgical tumor excision is the most important factor in prevention of recurrence. The tumor receives its blood supply from the branches of the internal carotid artery. A planned approach is necessary to minimize the blood loss and avoid postoperative morbidity. Due consideration must be given to critical structures such as the optic radiation which lie in close relation to the lateral ventricle. Radiation should be considered in cases with subtotal excision and a high grade, i.e., grade III. Meningiomas in children are known to occur in patients with neurofibromatosis type II (up to 40%) and in patients with radiation therapy taken in the past [4, 5]. Hence, a meticulous cutaneous and ophthalmological evaluation along with a detailed past history of the patient is necessary to rule them out. So far, an intraventricular location of meningioma has not been described in the reported cases of neurofibromatosis type II.

A brief tabulated summary of the 27 cases of primary intraventricular meningioma reported from 1955 till date is given in Table 1 [4, 6, 7, 9,10,11,12,13,14,15,16,17,18,19,20,21]. Ciurea et al. [15] achieved complete excision of a large 7-cm lateral ventricular meningioma in a 4-year-old girl. The preoperative neurological deficits improved with time although she required drainage of a large subdural hygroma postoperatively which improved her motor weakness even further. Nambiar A. and his colleagues [18] reported a case of an 11-year-old boy with pyrexia of unknown origin with an intraventricular chordoid meningioma. The fever subsided after surgical excision of the same. He developed recurrence after 1 year and underwent repeat surgery with adjuvant fractionated radiotherapy. The largest single reported series of six cases of pediatric intraventricular meningiomas is by Dash et al. [21]. The mean age of presentation was 14.6 years with a male preponderance and headache was the most frequent presenting complaint. Five out of six patients had a single tumor while one patient presented with multiple meningiomas with concurrent neurofibromatosis type II. Transcortical approach via the superior parietal lobule, middle temporal gyrus approach, and transcallosal approach were the surgical techniques attempted. Transitional meningioma was the commonest pathological diagnosis. Follow-up after surgical excision ranged from 6 to 36 months and there were no reported recurrence in any case.

Table 1 Brief summary of the reported cases of primary intraventricular meningiomas in the pediatric age group till date
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Conclusion

Intraventricular meningiomas are very rare brain tumors in children. The management of these tumors is complex yet well defined. Total surgical excision is the only curative treatment in spite of their deep location and vascularity. Endoscopic biopsy of these lesions can be safely performed for confirmation of diagnosis in doubtful cases. Possibility of neurofibromatosis should be considered in their management. Prognosis remains good in cases with complete surgical excision and careful handling of the vascular pedicles intraoperatively reduces the chances of postoperative morbidity and improves the quality of life.