Intraventricular cavernous haemangioma located at the foramen of Monro

Clinical History

A 26-year-old previously healthy female presented for headache over the past month. No neurologic deficit was found on physical exam.

Imaging Findings

Brain MRI revealed a 1.5 cm well-delineated lobulated mass at the antero-superior aspect of the third ventricle extending to the foramen of Monro.
This lesion showed a heterogeneous signal on T1-weighted images with hyperintense foci and heterogeneous signal on T2-weighted images with hypointense peripheral rim. (Fig. 1-2) Susceptibility weighted images demonstrated significant blooming artefacts. (Fig. 3)
No surrounding oedema, mass effect or hydrocephalus. (Fig. 4) Post-contrast T1 images showed no enhancement (Fig. 5).
Complete surgical resection of the lesion was done without any intra-operative complications. Histopathologic examination confirmed the diagnosis of cavernous haemangioma. Post-operative course was uneventful and the headache resolved completely.
Follow-up MRI after 10 weeks showed satisfactory control with no evidence of the residual mass.

Discussion

Cavernous haemangiomas (CH) represent 5 to 13% of central nervous system (CNS) vascular malformations. Intraventricular CH, however, are rare and represent almost 2.5-10.8% of cerebral cavernomas with only 102 published cases mentioned by Şanlı et al. [1]. These occur most likely in the lateral ventricles followed by the third and then the fourth ventricle [1]. Those occurring at the foramen of Monro are even rarer and so far only 16 cases of CH have been reported at the foramen of Monro including our case [2].
CH represent a group of CNS vascular malformations along with arteriovenous malformations, venous angiomas and capillary telangiectasia. CH are hamartomatous vascular malformations composed of sinusoidal vascular channels lined with thin endothelium predisposing them to recurrent bleeding. They lack large feeding or draining vessels [1].
Clinical presentation ranges from asymptomatic to fatal disease and depends on the size and location of the cavernoma. The most frequent initial symptom of intraventricular CH is due to mass effect, especially if located at the foramen of Monro, followed by haemorrhage and then seizure [1, 3].
Pathologically, they are well-circumscribed lobulated red to purple nodules. Histologically, they are formed of immature blood vessels and foci of haemorrhage at different stages of evolution without any intervening neural tissue [2].
On CT, CH present as an ovoid well-circumscribed hyperdense lesion related to calcifications, blood pool effect or recent haemorrhage, with no significant surrounding oedema [3]. The lesion can be subtle on CT in the absence of recent haemorrhage or calcifications [4]. MRI is the major diagnostic tool for detection and characterization of CH [1]. T1WI show variable signal depending on the haemorrhagic state and may show hyperintensities. T2WI reveal a "popcorn-like" lesion of mixed signal and a hypointense rim from haemosiderin deposition [5]. Enhanced images demonstrate no or mild enhancement [3]. These lesions are angiographically occult because of the low flow and the absence of feeding vessels [2].
Unlike asymptomatic intra-axial supratentorial CH, which can be managed conservatively, those occurring in the ventricular system require a more aggressive approach and complete resection because of their risk of extra-lesional bleed and tendency to rapid growth [4].
The preferred routes to resect CH located at Moro foramen are transcallosal, transfrontal transventricular and translamina terminalis approaches [1]. Radiosurgery can be considered for lesions at high risk locations [2]. The role of complete endoscopic resection remains controversial [4].

Differential Diagnosis List

Final Diagnosis

Intraventricular cavernous haemangioma

URL:	https://www.eurorad.org/case/12716
DOI:	10.1594/EURORAD/CASE.12716
ISSN:	1563-4086