Magnetic resonance imaging in the diagnosis of temporal bone and skull base lesions

Six patients are presented in whom total reliance on magnetic resonance imaging (MRI) interpretations would have resulted in less than ideal treatment. The misleading information on magnetic resonance imaging could be divided into two types; as follow: type I were those in which there was no signal but nonosseous pathology was present, and in type II an abnormal signal was present but misinterpreted. In three of these patients (cases, 2, 3, and 5), information gained from more traditional means (history, physical examination, audiologic and vestibular testing, and computed tomography) led to proper treatment, whereas, in two patients (cases 4 and 6), treatment exceeded that required by the disease process. In one patient (case 1), ideal therapy resulted, despite a negative magnetic resonance imaging study, when a small intracanalicular tumor was found fortuitously during a translabyrinthine vestibular nerve section for vertigo. Although magnetic resonance imaging provides excellent supplemental information to more traditional means of diagnosis, it cannot be used entirely in their place. As gadolinium-diethylene triamine pentaacetic acid (Gd-DTPA) becomes more readily available, as the resolution of magnetic resonance imaging improves, and as we gain more familiarity with this diagnostic modality, misleading information from these studies should decrease.