Have an account? Please log in.
Text size: Small font Default font Larger font
.
Radiology Daily
Radiology Daily PracticalReviews.com Radiology Daily

SSSE-EPI May Be Used Alone to Detect Focal Liver Lesions

February 3, 2008
Written by: , Filed in: Abdominal Imaging
  • Comments
.

The objective of a recent study was to determine if single-shot spin-echo echoplanar imaging (SSSE-EPI) can be used alone in the detection of focal liver lesions when compared to superparamagnetic iron oxide (SPIO)-enhanced MRI.

The study has concluded that single-shot spin-echo echoplanar imaging (SSSE-EPI) can potentially be used alone in the detection of liver hemangiomas and metastases when compared to SPIO-enhanced imaging.

Participants
25 patients with metachronous liver metastases from colorectal carcinoma.

Methodology
A 1.5-Tesla MRI scanner was used. Respiratory triggered SSSE-EPI fat-suppressed images were obtained with b-values of 0, 10, 150, and 400 seconds/mm(2). Subsequently, T2-weighted TSE, T2*-gradient echo, and T1-weighted gradient echo in and out of phase sequences were performed. T1-weighted 3-D gradient echo fat-suppressed images were performed before and during the arterial, portal venous, late venous, and 15-minute delayed phase following intravenous administration of SPIO. T2-weighted TSE and T2*-gradient echo fat-suppressed images were obtained >15 minutes after SPIO administration. Lesion detection was performed by two radiologists with experience in abdominal MRI.

Related CME:
NEW FOR 2009
Abdominal & Thoracic CT/MR/US: Optimizing Practice
The University of California, San Francisco School of Medicine
Evolving technology improves radiological practice through improved image quality for anatomical interpretation and generation of functional data. The use of MDCT and fast, multi-phase imaging sequences also translates to a tremendous increase in data that requires review and handling and greater need for contrast and radiation safety awareness. This activity targets the community radiologist involved in body and cardiovascular imaging with a focus on developing an efficient workflow practice in the modern imaging environment.
Read more or order: Abdominal & Thoracic CT/MR/US: Optimizing Practice

CT/MRI of the Abdomen and Pelvis
University of California San Francisco Department of Radiology and Biomedical Imaging
Provides an updated review on the use of helical (single and multidetector-row) CT and MRI for imaging of the abdomen and pelvis. Participants will learn the current approach and uses of CT/MRI in the examination of the abdomen and pelvis including advances in abdominal MRI techniques, genitourinary applications of CT/MRI, CT colonoscopy, CT/MR angiography, and CT cholangiography.
Earn up to 12 AMA PRA Category 1 Credits™.
Abdominal Imaging CME

Results of the Study
95 hepatic lesions were detected on diffusion- and SPIO-enhanced images, including 25 hemangiomas and 70 metastases. The diffusion-weighted images (DWIs) with a b-value of 10 seconds/mm(2) were significantly better than the SPIO-enhanced images for the detection of liver metastases. This sequence demonstrated the best results for detecting lesions <10 mm in size that were near intrahepatic vessels. All lesions that were not appreciated on the different sequences measured <10 mm. All 95 lesions were seen as hyperintense focal liver lesions on all b-value SSSE-EPIs. Consequently, differentiation between liver hemangiomas and metastases was not possible using DWIs alone. Using the remainder of the sequences, 92% of the hemangiomas demonstrated typical imaging features, while 76% of the metastases could be characterized. All metastases that could not be characterized were <10 mm in size. Reviewer’s Comments
DWIs can aid in the detection of liver lesions. This is particularly helpful when employing a low b-value, which provides a black blood effect and consequently makes it possible to discern lesions from nearby intrahepatic vessels. However, this sequence is currently not specific in differentiating between some benign and malignant liver lesions and should not be relied on in isolation but should complement the standard MR abdominal imaging protocol.

One limitation reported in this study was that there was a lack of histological proof in many of the lesions. When intraoperative ultrasound with resection could not be performed, follow-up imaging was used as a reference standard.

Author: John C. Sabatino, MD

Reference:
Coenegrachts K, Orlent H, et al. Improved Focal Liver Lesion Detection: Comparison of Single-Shot Spin-Echo Echo-Planar and Superparamagnetic Iron Oxide (SPIO)-Enhanced MRI.
J Magn Reson Imaging; 2008; 27 (January): 117-124

.
  • Comments
.

Would you like to keep current with radiological news and information?

Post Your Comments and Responses

Comments are closed.