Pseudotumour of the maxillary antrum.

Orbital pseudotumour is a non-specific inflammation of the orbit which forms a tumour-like mass composed of increased connective tissue and ground substance with vascular proliferation and an infiltrate of chronic inflammatory cells. No demonstrable aetiological agents are found locally, and there is no evidence of specific disease entities such as Hodgkins, SLE or temporal arteritis. The condition may present in many different ways to the otolaryngologist, and is therefore a rare but important differential diagnosis to be born in mind. We report a rare case of orbital pseudotumour presenting initially with involvement of the maxillary antrum and in association with Riedel's thyroiditis.