Superparamagnetic iron oxide-enhanced MR imaging for focal hepatic lesions: a comparison with CT during
Akihiro Tanimoto1, Go Wakabayashi, Hiroshi Shinmoto
1Department of Diagnostic Radiology, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582, Japan.
Background:
We aimed to evaluate the efficacy of a breath-hold superparamagnetic iron oxide (SPIO)-enhanced magnetic resonance (MR) imaging protocol for the detection of focal hepatic lesions, in comparison with a non-breath-hold SPIO-enhanced imaging protocol and computed tomography during arterioportography (CTAP) plus CT during hepatic arteriography (CTHA).
Methods:
Findings of SPIO-enhanced MR imaging and CTAP/CTHA for 24 hepatic metastases in 17 patients and 29 HCCs in 21 patients were analyzed. All patients underwent breath-hold SPIO-enhanced MR imaging (1.5 tesla), breath-hold plus non-breath-hold SPIO-enhanced MR imaging, and CTAP plus CTHA prior to partial hepatectomy or laparoscopic ablation therapy. Histopathology for lesion characterization and intraoperative ultrasound for lesion detection were available for all patient. Breath-hold SPIO-enhanced MR imaging consisted of T2-weighted single-short fast spin echo (FSE), T2-weighted (T2W) FSE, T2*-weighted gradient echo (GRE), and T1-weighted GRE. For the non-breath-hold imaging protocol, respiratory-triggered, fat-suppressed T2W-FSE was added to the breath-hold MR imaging protocol. Double phase CTAP plus CTHA was performed on an angio-CT system. To compare the three imaging protocols, three radiologists performed blind film reading, and all data, on a hepatic segment-to-segment basis, were entered for alternative free-response receiver-operating characteristic (AFROC) analysis.
Results:
ROC analysis showed that there was no significant difference in the area under the AFROC curve (A1) value for metastases and HCCs among the three protocols; the breath-hold SPIO-enhanced MR imaging protocol, non-breath-hold MR imaging protocol, and CTAP plus CTHA. The breath-hold SPIO-enhanced MR imaging protocol showed a sensitivity, specificity, and accuracy equivalent to the non-breath-hold MR imaging protocol and CTAP plus CTHA.
Conclusions:
As a preoperative test, SPIO-enhanced MR imaging could have the potential to replace CTAP plus CTHA in a certain clinical setting.
Insights
Superparamagnetic iron oxide (SPIO)-enhanced MRI shows efficacy comparable to CTAP/CTHA for detecting liver lesions. This breath-hold MRI protocol offers a potential replacement for CTAP/CTHA in preoperative liver imaging.
Area of Science:
- Radiology
- Medical Imaging
- Hepatobiliary Imaging
Background:
- Evaluating diagnostic efficacy of breath-hold SPIO-enhanced MRI for focal hepatic lesions.
- Comparison with non-breath-hold SPIO-enhanced MRI and CTAP/CTHA.
- Assessing imaging protocols for hepatic metastases and hepatocellular carcinoma (HCC).
Purpose of the Study:
- To compare the efficacy of breath-hold SPIO-enhanced MRI with non-breath-hold SPIO-enhanced MRI and CTAP/CTHA for detecting focal hepatic lesions.
- To determine if breath-hold SPIO-enhanced MRI can replace CTAP/CTHA in preoperative settings.
Main Methods:
- Analysis of SPIO-enhanced MRI and CTAP/CTHA findings in patients with hepatic metastases and HCC.
- All patients underwent breath-hold SPIO-enhanced MRI, non-breath-hold SPIO-enhanced MRI, and CTAP/CTHA.
- Histopathology and intraoperative ultrasound used for lesion characterization and detection.
- Radiologists performed blind film reading and AFROC analysis.
Main Results:
- No significant difference in AFROC curve area (A1) among the three protocols for metastases and HCC.
- Breath-hold SPIO-enhanced MRI demonstrated equivalent sensitivity, specificity, and accuracy compared to non-breath-hold MRI and CTAP/CTHA.
Conclusions:
- SPIO-enhanced MRI, particularly the breath-hold protocol, is effective for detecting focal hepatic lesions.
- Breath-hold SPIO-enhanced MRI shows potential as a preoperative imaging test, possibly replacing CTAP/CTHA in specific clinical scenarios.
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Description of the Procedures
Computed Tomography (CT) scan:
Computed Tomography (CT) scans use X-ray technology to generate detailed images of bones, organs, and tissues. During the scan, the patient lies on a moving table...