Diffusion-Weighted MR Imaging before and after Contrast Enhancement with Superparamagnetic Iron Oxide for Assessment of Hepatic Metastasis.
10.3349/ymj.2012.53.4.825
- Author:
Hana KIM
1
;
Jeong Sik YU
;
Dae Jung KIM
;
Jae Joon CHUNG
;
Joo Hee KIM
;
Ki Whang KIM
Author Information
1. Department of Radiology, Gangnam Severance Hospital, Yonsei University College of Medicine, Seoul, Korea. yjsrad97@yuhs.ac
- Publication Type:Original Article
- Keywords:
Liver;
metastasis;
diffusion magnetic resonance imaging;
superparamagnetic iron oxide (SPIO)
- MeSH:
Adult;
Aged;
Aged, 80 and over;
Contrast Media/chemistry/*diagnostic use;
Diffusion Magnetic Resonance Imaging/*methods;
Female;
Ferric Compounds/chemistry/*diagnostic use;
Humans;
Liver Neoplasms/*diagnosis;
Male;
Neoplasm Metastasis/*diagnosis
- From:Yonsei Medical Journal
2012;53(4):825-833
- CountryRepublic of Korea
- Language:English
-
Abstract:
PURPOSE: The purpose of our study was to validate diffusion-weighted MRI (DWI) before and after superparamagnetic iron oxide (SPIO) injection for assessment of hepatic metastases. MATERIALS AND METHODS: Eighty-six hepatic metastases (size range, 0.3-4.7 cm; mean, 1.5 cm) verified pathologically or by follow-up imaging studies in 22 consecutive patients (17 men and 5 women; 44-83 years; mean age, 60 years) during a 13-month period were enrolled. Hepatic MRI, including DWI (b-factors=50, 400, 800 s/mm2) with breath-holding technique of single-shot spin-echo echo-planar imaging (TR/TE=1000/69 ms, average=2) before and after SPIO administration, were retrospectively reviewed by two independent radiologists with a 5-point scale confidence score for each hepatic lesion on pre-contrast DWI (pre-DWI), SPIO-enhanced DWI (SPIO-DWI), and SPIO-enhanced T2*-weighted imaging (SPIO-T2*wI). RESULTS: For all lesions, SPIO-T2*wI showed significantly higher confidence score in the diagnosis of hepatic metastases than pre-contrast or SPIO-DWI regardless of the size of b-factors (p<0.05) with only one exception; using b-factor=50 s/mm2, the score of SPIO-T2*wI was still higher than SPIO-DWI but there was no statistical significance given by observer 1 (p=0.730). For the subcentimeter lesions (n=37), SPIO-T2*wI showed the highest score, and using b-factor=50 or 400 s/mm2 SPIO-DWI showed similar confidence scores to SPIO-T2*wI by both observers (p>0.05). Pre-DWI using b-factor=50 sec/mm2 was also comparable with SPIO-T2*wI by observer 1 (p=0.060). CONCLUSION: Pre-DWI has a limited value for the assessment of hepatic metastases, however, the repetition of DWI after SPIO injection using small b-factors could complement SPIO-T2*wI, especially for subcentimeter lesions.
