Ito S, Fuwa N, Nomura M, et al. - For cases of head and neck cancer treated with intra-arterial chemotherapy, researchers sought to establish objective indices for ascertaining the distribution of anticancer drugs administered to multiple arteries. In MRI, changes in 1/T 1 (Δ1/T 1) are linked with the contrast agent concentration. Focusing on these properties, they examined whether anticancer drug concentrations can be estimated within tissue based on Δ1/T 1. The fast spin echo (FSE) sequence was employed to ascertain optimum imaging parameters using a phantom. Thereafter, seven cases of tongue cancer were administered a contrast agent via the lingual and external carotid arteries. Tumor and nontumor tissues were assessed for Δ1/T 1. For the FSE, two repetition times (TR, 500 and 1000 ms) was the optimum imaging parameters. Significantly higher Δ1/T1 was evident in both tumor and nontumor tissues (2.13 and 2.62 times, respectively) in correlation with the lingual artery administration of contrast agent vs the external carotid artery administration. Findings suggest the possible utility of this method in determining intratissue concentrations of intra-arterially administered anticancer drugs, thus possibly yielding valuable information in determining the distribution of anticancer drugs.