This is a comparison of the ability of two quantitative magnetic resonance (MR) indices: (a) the second echo signal drop (SESD) (a simplified index of T2 relaxation times that we have developed); and (b) the previously described lesion/liver signal intensity ratio (LLR) to provide histologic diagnosis in hepatic lesions greater than 2 cm in diameter. In 55 patients 108 hepatic masses [31 cavernous hemangiomas (CH), 68 metastases, and 9 hepatocellular carcinomas] were scanned at 0.5 T. Statistically significant differences between CH and malignant lesions were obtained in mean SESD (p = 0.0006) and LLR (p = 0.0008) using repetition time (TR) 2,100/echo time (TE) 35, 60 ms. Application of cutoff values derived from receiver-operator characteristic analysis led to a correct diagnosis in 100 and 94% of lesions, respectively. Using TR 2,100/TE 35, 90 ms in a different patient population, CH and malignancies again displayed significantly different mean values, using the SESD (p = 0.0090) and LLR (p = 0.0024) methods. These measurements provided a correct diagnosis in 74 and 81%, respectively. Accuracy was increased in those cases in which the diagnosis by SESD and LLR were concordant. When compared with visual analysis, these quantitative methods appear to achieve near 100% accuracy in the differentiation of hepatic CH from malignancies.