Preoperative Embolisation and Surgical Resection of a Giant Anterior Skull Base Meningioma

Introduction

Skull base meningiomas can be highly vascular tumours, and their vascularity may complicate or limit resection because of intraoperative blood loss.1,2 Surgical devascularisation can be challenging in practice, particularly for tumours arising along the skull base in locations that prevent access to the vascular pedicle until later stages of the resection.3,4 Embolisation of meningiomas may be performed preoperatively when surgical devascularisation is expected to be challenging. Preoperative embolisation of meningiomas has been advocated to facilitate intraoperative resection by decreasing surgical blood loss through occlusion of feeding arteries, as well as by shrinking, softening, and sometimes inducing necrosis in the tumour in ways that sometimes facilitate mechanical removal and reduced operative duration.3

Case Report

A 45-year-old female patient presented with complaints of headache and personality changes for the past two months. She also had difficulty in perceiving smell. On examination, she had anosmia, 6/6 vision in both eyes, and fundus examination revealed bilateral papilloedema. The rest of the clinical examination was unremarkable. Magnetic resonance imaging (MRI) revealed a large, contrast-enhancing lesion arising from the anterior skull base involving the crista galli, planum sphenoidale and tuberculum sellae, suggestive of a giant anterior skull base meningioma (Figure 1A–C).

In view of the large size of the lesion, the decision to perform a pre-operative digital subtraction angiography (DSA) with tumour embolisation was taken. Diagnostic angiographic runs, from the right external carotid artery, revealed feeders from the accessory middle meningeal artery (MMA) (distal branch of internal maxillary artery) giving rise to a characteristic tumour blush (Figure 2A–B). A similar tumour blush was noted from the left accessory MMA.

Discussion

Anterior skull base meningiomas can have a varied and complex vascular supply. The anterior and/or posterior ethmoidal arteries are the major arterial feeders in more than 13% of skull base meningiomas. The vascular supply of meningiomas in the olfactory groove and planum sphenoidale can arise from dural, transosseous, and even pial feeders.1 These tumours may also be fed by art these feeders is done through special microcatheters. However, aggressive embolisation can be fraught with permanent postprocedural neurological deficits in view of external and internal carotid artery anastomoses, which may sometimes not be visible. eries that supply the anterior branch of the MMA, the recurrent meningeal branches of the ophthalmic artery (OphA) and lacrimal artery, the meningeal branches of the internal carotid artery (ICA), the tentorial branch of the meningohypophyseal trunk (MHT), and the terminal branches of the internal maxillary artery (IMA), accessory meningeal artery.1,5 Super selective embolisation of these feeders is done through special microcatheters. However, aggressive embolisation can be fraught with permanent postprocedural neurological deficits in view of external and internal carotid artery anastomoses, which may sometimes not be visible.

Tumour embolisation decreases the tumour vascularity and initiates tumour necrosis, making the tumour consistency soft and more amenable to surgical resection. The necrotic areas can be identified on the postembolisation MRI as hypointense areas of decreased contrast uptake, which were noted in this case.