Design We report the case of an incidental pituitary mass discovered in the context of bilateral cavernous sinus thrombosis due to a bacterial pansinusitis. Conclusions Magnetic resonance imaging features of the pituitary lesion, together with transient central hypogonadism and total regression of the mass after anticoagulation and antimicrobial therapy, suggest that this lesion is a pituitary oedema of vascular mechanism. Other possible causes of pituitary mass in such a situation are also discussed.