The authors use case studies to illustrate the respective benefits of CT and MR imaging in the management of sphenoid sinus disease. Because the sphenoid sinus is located deep in the skull base adjacent to vital neurological and vascular structures, surgery involves a certain risk. The improved quality of imaging now available provides essential information on which to base therapeutic options. Since CT and MR findings make it possible to increase the precision of the pretherapeutic evaluation and to determine neurological and vascular involvement, these imaging studies have become an integral part of the successful management of sphenoid sinus disease.