Between 1983 and 1991 ten patients with chronic frontal sinus disease underwent frontal osteoplastic flaps with fat obliteration. In order to judge operative success on a long-term basis all patients were called for postoperative follow-up. They then completed a questionnaire, in which they were asked about postoperative complaints. Additionally, sinuses were examined by computed tomographic (CT) and magnetic resonance imaging (MR). Among the patients evaluated seven had no complaints, and no evidence of disease could be found by medical examination. CT scans showed complete obliteration of the frontal sinuses in all patients. In these patients, two-thirds of the fat had been replaced by connective tissue. MR was used in an attempt to show evidence for suppurative disease in the frontal sinus, but the MR images failed to correlate with symptoms. Additional results could not be obtained when compared to CT. Overall operating success could only be determined by clinical assessment and confirmed the value of the frontal osteoplastic flap with fat obliteration.