Combining diffusion-weighted MR imaging with Gd-EOB-DTPA enhanced MR imaging improves the detection of colorectal liver metastases

Introduction: In patients with colorectal cancer, accurate assessment of the size, location and segmental distribution of liver metastases on a per-lesion basis is critical for treatment planning. Diffusion-weighted MR imaging (DW-MRI) has a high sensitivity and specificity for liver metastasis detection [1-3]. Combining DW-MRI with T1-weighted imaging after liver specific contrast medium Magafodipir trisodium (MnDPDP) administration, improved the diagnostic accuracy compared with either technique alone [2]. Gadolinium-ethoxybenzyl-DTPA (Gd-EOB-DTPA; Primovist®) is a relatively new hepatocyte selective MR contrast medium that is useful for detecting smaller (< 1 cm) liver metastases [4]. Delayed T1-weighted Imaging at 20 – 60 minutes after contrast demonstrates metastases as hypointense lesions against the avidly enhancing liver parenchyma. However, the value of combining DW-MRI with Gd-EOB-DTPA enhanced MR imaging for detecting colorectal liver metastases has not been established.