Sigmoid sinus thrombosis (SST) has become increasingly uncommon. In the pre-antibiotic era this condition had a mortality rate of over 90%.1 A high index of suspicion is required to make the diagnosis. We present a rare case of sigmoid sinus thrombosis secondary to mastoiditis, which illustrates the problems of delayed diagnosis. This report highlights the importance of rapid diagnosis and early surgical intervention. We emphasis the need for scanning and otolaryngology referral in all cases of middle ear disease associated with pain or vertigo which does not resolve rapidly on appropriate antibiotic therapy.