Purpose:

The purpose of our study was to evaluate the efficacy of echo planar imaging (EPI) as a breath-holding T2-weighted technique for imaging focal hepatic lesions.

Method:

Forty-eight patients with focal hepatic lesions (9 metastases, 21 hepatocellular carcinomas, 1 cholangiocarcinoma, 16 hemangiomas, and 2 cysts) underwent single shot EPI with and without a small diffusion-sensitizing gradient (DSG)(b values= 55 s/mm 2) at 1.5 T. Comparison was made with breath-holding T2-weighted fast SE (FSE) sequences.

Results:

Lesion-to-liver signal intensity ratio of EPI was significantly better than that of T2-weighted FSE (p< 0.05) in patients with metastasis. Use of DSG suppressed bright signals from vessels or periportal tissue, resulting in better conspicuity of small lesions. EPI with DSG visualized more metastatic deposits than T2-weighted FSE (p< 0.01).

Conclusion:

EPI with a small DSG is helpful for detection of small hepatic metastases.

Recent technical advances in MRI have enabled acquisition of abdominal images during a single breath-hold (1-9). MRI with breath-holding has been successfully applied to the T1-weighted imaging of the liver, particularly in combination with dynamic gadoliniumenhanced imaging techniques (1-4). As for T2-weighted liver imaging, however, the advantage of breath-hold sequences has been less convincing (2, 5-8). Several recent studies have reported that lesion-to-liver contrast in T2-weighted imaging with fast SE (FSE) techniques using breath-holding was suboptimal in comparison with conventional SE or FSE sequences not using breath-holding (6-8).