RESUMO
AIM: To elucidate whether warming may reduce the viscosity of miriplatin-lipiodol suspension (MPT/LPD) and also the injection pressure through microcatheters, for potential use as a chemotherapeutic agent of transarterial chemoembolization (TACE) for hepatocellular carcinoma (HCC). METHODS: Viscosity of MPT/LPD prepared at on-label dose was measured in vitro at 25°C, 30°C, 40°C, 50°C and 60°C using capillary tube method. Reproducibility of viscosity change was also tested. Injection pressure through two different commercially available microcatheters was measured using a rheometer. Data sampling was performed at least twice for each measurement. RESULTS: Viscosity of MPT/LPD was significantly reduced as the temperature was elevated (R(2) = 0.9586, P < 0.0001, Pearson's correlation); at 40°C, it was almost half of that at room temperature (25°C). Repeated warming and cooling down of MPT/LPD revealed good reproducibility of viscosity change. Injection pressure through either microcatheter showed significant reduction when MPT/LPD was warmed (P < 0.05, Spearman's rank correlation coefficient). CONCLUSION: The viscosity and injection pressure through microcatheters of MPT/LPD was confirmed to reduce significantly as the temperature is elevated. MPT/LPD warmed to 40°C has half viscosity as that at room temperature and is considered suitable for clinical use. Warming MPT/LPD may have potential to facilitate the procedure of TACE for HCC.
RESUMO
We have developed a new target-irradiation system for the online preparation of multitracer solutions, where the nuclear-reaction products recoiling out of the target are directly implanted in a solvent as a liquid catcher. A rapid online transportation of the solution has enabled highly efficient recovery of the multitracer solutions having even short-lived radioactive isotopes without any chemical treatments. It has been suggested that the collection efficiency depends on the chemical properties of the recoil elements.