A comparison of noninvasive imaging modalities in the melanoma patient.

The results of radionuclide (RN) liver scans, computed tomography (CT), and ultrasonography (US) were compared in 163 patients. Thirty-eight patients had all three studies, while ten were examined by CT and RN liver scans. One hundred fifteen patients had only US and RN studies. Radionuclide liver scanning demonstrated more false positive and negative studies than CT or US. Also, CT and US demonstrated more areas of metastasis during a single examination than RN liver scans. Ultrasonography displayed roughly the same accuracy of CT when a technically adequate examination was obtained. However, US was hampered by technically inadequate studies in 19% of 153 patients because of interfering intestinal gas. Computed tomography proved the most accurate and reliable modality in 48 patients.