Endoscopic transnasal resection of sinonasal haemangiopericytoma involving anterior skull base: a case report and literature review.

Haemangiopericytoma is an uncommon vascular tumour of the sinonasal region with different clinical and pathological presentations. Given its origin from Zimmerman's pericytes around the capillaries, profuse bleeding during surgical manipulation is a characteristic sign. The open approach, with or without pre-operative embolisation, is therefore the usual technique for the resection of a large sinonasal haemangiopericytoma. We report on a case of haemangiopericytoma with massive unilateral involvement of the maxillary, anterior and posterior ethmoids, sphenoid, and frontal sinuses with extension to the ipsilateral orbit causing proptosis and diplopia. The tumour was completely removed endoscopically, and the dura exposed in the posterior part of the frontal recess was covered with a septal mucosal graft.