Small hepatic nodules in cirrhosis: ultrasonographic, CT, and MR imaging findings

Purpose: The purpose of this study was to assess the imaging findings of pa thologically-proved small hepatic nodules 2 cm in size or smaller detected with ultrasonography in cirrhotic patients with suspected hepatocellular ca rcinoma (HCC). Materials and Methods: We evaluated sonographically detected 32 small hepat ic nodules which were pathologically confirmed in 23 consecutive cirrhotic patients who were suspected of having HCC. Twenty-six lesions were confirme d with ultrasonographically-guided aspiration needle-core biopsy, and six w ith definitive surgery. Ultrasonographic examination records Mere retrospec tively reviewed. CT, and MR images obtained with various imaging techniques were retrospectively reviewed by two radiologists in a blind fashion. Results: The 32 hepatic nodules were comprised of seven focal fatty changes , two large regenerative nodules, three low-grade dysplastic nodules, five high-grade dysplastic nodules, and fifteen HCCs. Ultrasonography showed var ious echogenicity for the hepatic nodules. The signal-intensity characteris tics with T1-weighted spin-echo, in-phase gradient-recalled-echo, and dynam ic MR imagings may be useful in distinguishing HCC from nonHCC nodules. Conclusions: Nearly half of small hepatic nodules detected with ultrasonogr aphy were nonHCC nodules. Ultrasonographic findings may not be reliable in characterizing small hepatic nodules in cirrhosis. CT and MR imaging obtain ed with the various techniques are still insensitive to these hepatic nodul es.