An unusual clivus mass is reported, following investigation of memory disturbance and headaches in a patient with β thalassaemia and sickle cell disease. This lesion proved to be a site of extramedullary haematopoiesis.

Computed tomography demonstrated a 2 cm mass at the base of the sphenoid. However, magnetic resonance imaging showed little bony expansion, and the differential diagnosis included chordoma, dermoid cyst and fibrodysplasia.

Examination of the biopsy showed the presence of bone marrow demonstrating erythroid hyperplasia and small aggregates of B-cell lymphocytes. The features were considered compatible with erythroid hyperplasia associated with haemolytic anaemia.

The patient was reassured that she did not have a neoplastic lesion, and was referred back to the haematologists for further management of her sickling β thalassaemia.

Extramedullary haematopoiesis occurs outside the reticuloendothelial system in response to haemolytic anaemia. Extramedullary haematopoiesis causing a clivus mass is an unusual ENT presentation. Such haematopoiesis is occasionally seen in the calvarial skull, but this is the first report of this process occurring in the anterior skull base, to our knowledge.

We report a case of allergic fungal sinusitis causing bone erosion and diplopia.

A 43-year-old man presented with a four-month history of increased nasal congestion and progressive diplopia. Clinical examination revealed bilateral nasal polyposis and a right lateral gaze deficit, consistent with a VIth cranial nerve palsy. Computed tomography of the paranasal sinuses demonstrated a large sellar mass with extensive bony erosion and both supra- and infra-sellar extension. An endoscopic approach to the sphenoid sinus, clivus and posterior cranial fossa with image guidance was performed, enabling surgical treatment involving nasal polypectomy, wide marsupialisation of the sphenoid sinus and removal of the extensive allergic fungal mucin. The patient awoke from anaesthesia with complete resolution of his diplopia.

Otolaryngologists should be aware that approximately 20 per cent of patients with allergic fungal sinusitis demonstrate paranasal sinus expansion and bone erosion involving surrounding anatomical structures. Such patients may have clinical findings involving the orbit and cranial vault.