Hepatic transit time of an echo enhancer:: an indicator of metastatic spread to the liver

Objective Can sonographic measurements of the transit time of an echo enhancer from the hepatic artery to the hepatic vein discriminate between patients with and without liver metastases? Method The hepatic transit time (hepatic artery to hepatic vein delay) of an echo enhancer (Optison) was measured in pulse inversion mode on the basis of time intensity curves (TIC) in patients with gastrointestinal tumours with proven liver metastases and in patients without liver metastases. Results Sixty-four patients (46 males, 18 females, mean age 61 +/- 13 years) were admitted to the study. Fourteen patients had metastatic growth in the liver with a primary tumour in situ (group A). Fourteen patients had liver metastases following primary tumour resection (group B). Twenty-eight patients had a known primary tumour but no liver metastases (group C), and eight patients had neither liver symptoms nor a primary tumour (group D). The mean hepatic transit time in patients with liver metastases was 6.6 +/- 1.8 s in group A and 6.7 +/- 1.7 s in group B, whereas in patients without liver metastases it was significantly longer; namely, 15.7 +/- 4.4 s in group C and 15.0 +/- 2.0 s in group D (P< 0.001). The transit times in all patients with liver metastases were less than or equal to 10 s, while in all patients without metastases except for four the times were greater than or equal to 12 s and one of the four had already developed liver metastases on early follow-up. Conclusions Measurement of the hepatic transit time permits discrimination of patients with and without liver metastases. (C) 2004 Lippincott Williams Wilkins.