Diffusion-weighted and T2-weighted MR imaging for colorectal liver metastases detection in a rat model at 7 T: a comparative study using histological examination as reference

作者：Wagner Mathilde^*; Maggiori Leon; Ronot Maxime; Paradis Valerie; Vilgrain Valerie; Panis Yves; Van Beers Bernard E

来源：European Radiology, 2013, 23(8): 2156-2164.

DOI：10.1007/s00330-013-2789-y

• Liver neoplasms
• Neoplasm metastasis
• Colorectal neoplasms
• Diffusion magnetic resonance imaging
• Animal model

To compare diffusion-weighted (DW) and T2-weighted MR imaging in detecting colorectal liver metastases in a rat model, using histological examination as a reference method. %26lt;br%26gt;Eighteen rats had four liver injections of colon cancer cells. MR examinations at 7 T included FSE-T2-weighted imaging and SE-DW MR imaging (b = 0, 20 and 150 s/mm(2)) and were analysed by two independent readers. Histological examination was performed on 0.4-mm slices. McNemar%26apos;s test was used to compare the sensitivities and the Wilcoxon matched pairs test to compare the average number of false-positives per rat. %26lt;br%26gt;One hundred and sixty-six liver metastases were identified on histological examination. The sensitivity in detecting liver metastases was significantly higher on DW MR than on T2-weighted images (99/166 (60 %) (reader 1) and 92/166 (55 %) (reader 2) versus 77/166 (46 %), P a parts per thousand currency signaEuro parts per thousand 0.001), without an increase in false-positives per rat (P = 0.773/P = 0.850). After stratification according to metastasis diameter, DW MR imaging had a significantly higher sensitivity than T2-weighted imaging only for metastases with a diameter (0.6-1.2 mm) similar to that of the spatial resolution of MR imaging in the current study. %26lt;br%26gt;This MR study with histological correlations shows the higher sensitivity of DW relative to T2-weighted imaging at 7 T for detecting liver metastases, especially small ones. %26lt;br%26gt;aEuro cent Diffusion weighted (DW) sequences are increasingly used in magnetic resonance imaging (MRI). %26lt;br%26gt;aEuro cent DW has higher sensitivity for liver metastases than T2-weighted imaging at 7 T. %26lt;br%26gt;aEuro cent This increase in sensitivity is especially marked for small liver metastasis detection. %26lt;br%26gt;aEuro cent This higher sensitivity is confirmed in an animal model with histological correlation. %26lt;br%26gt;aEuro cent DW imaging has the potential for earlier diagnosis of small liver metastases.

• 出版日期2013-8