Frequency of benign hepatic lesions incidentally detected with contrast-enhanced thin-section portal venous phase spiral CT

Purpose: To evaluate the frequency of benign focal hepatic lesions incident ally detected at contrast-enhanced thin-section portal venous phase spiral CT. Material and Methods: Between January 1998 and February 1999, contrast-enhanced hepatic spiral CT examinations were performed in 1,892 patients. Out of these, only 100 patients fulfilled the following inclusion criteria: No underlying mal ignant disease, no liver cirrhosis, no suspected or known focal liver lesio ns. Standardized spiral CT parameters were applied. All CT studies were rev iewed retrospectively by one radiologist. Any focal lesion was recorded and classified. Lesion size and number were noted. Results: A total of 108 hepatic lesions were reported in 33 out of 100 pati ents (80 cysts; 18 hemangiomas; 3 focal fatty infiltrations; 2 focal non-tu morous perfusion defects; 1 calcification; and 4 non-classified lesions). T he average lesion size was 9.4 mm (less than or equal to5 mm: n=40; 6-10 mm : n=30; 11-15 mm: n=28; >15 mm: n=10). Conclusions: Benign liver lesions are probably a frequent incidental findin g at abdominal spiral CT.