Hepatic tumor imaging using iron oxide MRI: Comparison with computed tomography, clinical impact, and cost analysis

Background: The surgical management of hepatic tumors has traditionally rel ied on preoperative contrast-enhanced computed tomography (CECT) in combina tion with intraoperative ultrasonography (IOUS). Unfortunately, the ability to detect and characterize hepatic tumors by using CECT is limited, and IO US frequently reveals additional disease that alters the operative approach . Recent advances in hepatic magnetic resonance imaging (MRI) may improve p reoperative tumor detection and characterization; however, little is known about how MRI compares with CECT or about the clinical impact and cost cons iderations of liver MRI. Methods: A retrospective chart review was performed to compare iron oxide ( Feridex [Fe])-MRI with CECT in the preoperative imaging of hepatic neoplasm s, eis well as to determine the clinical impact and overall healthcare cost s associated with Fe-MRI. Results: Of approximately 1000 patients who underwent abdominal MRI at a si ngle institution during a 20-month period, 57 were identified who underwent Fe-MRI evaluation of the liver. Indications for imaging included suspected metastases (n = 43), an indeterminate hepatic mass (n = 9), or primary hep atic cancer (n = 5). Overall, Fe-MRI identified a total of 157 lesions (mea n, 2.75 per patient; range, 0-14). CECT was performed in SO patients, of wh om 35 had primary or metastatic cancer. Fe-MRI identified more lesions than CT (n = 136 vs. 77; P = .016), and the average size of lesion detected by Iie-MRI was significantly smaller than that by CECT (2.5 vs. 3.4 cm; P = .0 18). Comparison of CECT and I;e-MRI findings with IOUS and pathological spe cimens showed a significant difference in sensitivity (MRI, 86%; CECT, 58%; P < .001), and IOUS changed the operative approach in only 5% of those ima ged with Fe-MRT. Overall, Fe-MRI altered the clinical management in 67% of patients imaged (n = 38 of 57), which corresponded to an overall net cost s avings of $108,368 ($1,901 per patient). Conclusions: Fe-MRI is a powerful imaging technique, with greater hepatic t umor detection sensitivity than CECT. Moreover, it is an economically feasi ble imaging method that will alter the clinical management in most patients imaged.