MRI of the head was performed in 25 patients suffering from Wegener's granulomatosis. 23 patients showed mucosal inflammation in the nasal cavity and in the paranasal sinuses, 10 patients had granulomas in the paranasal sinuses and in the orbits, 7 patients had cerebral lesions, 3 patients had submucosal hemorrhages in the paranasal sinuses and 3 patients showed bone erosions or destructions in the facial skeleton, which was visible only by CT.