Hepatic hemangiomas and malignant tumors: improved differentiation with heavily T2-weighted conventional spin-echo MR imaging.

PURPOSE

To determine whether hemangiomas and malignant tumors can be better differentiated at 1.5-T magnetic resonance imaging with use of more heavily T2-weighted conventional spin-echo sequences.

MATERIALS AND METHODS

Eighty-three patients with focal liver lesions (50 malignant tumors, 24 hemangiomas, nine cysts) larger than 1 cm were studied with a 3,000/80, 160 sequence (repetition time msec/echo time [TE] msec). T2 relaxation times and lesion/liver signal intensity ratios at TEs of 80 and 160 msec were measured. Receiver operating characteristic (ROC) analyses of expert readers and quantitative measures were performed.

RESULTS

T2 relaxation times demonstrated the best performance in distinguishing hemangiomas from malignant tumors (area under ROC curve = .99 +/- .01). Mean T2 times were 76 msec +/- 11 for malignant tumors, 142 msec +/- 40 for hemangiomas, and 341 msec +/- 38 for cysts. A cutoff T2 value of 112 msec allowed discrimination between hemangiomas and malignant tumors with a 97% accuracy, 100% sensitivity, and 92% specificity.

CONCLUSION

Hemangiomas and malignant tumors are better differentiated with use of T2 relaxation times obtained with a more heavily T2-weighted sequence.