Introduction: Liver metastasis is detected in more than one million people in each year. Only 10% of them are eligible for surgery. Radiofrequency ablation is the most popular local ablation technique for the management of the other 90% of the metastases. Complete ablation of the lesion with a safe margin is the goal of such a local ablative method. There is no routine available technique for monitoring the treatment process. MRI is the only method which can monitor tissue ablation in real time however interaction of radiofrequency energy by MRI acquisition makes it impossible for clinical use.Materials and Methods: In our in-vitro study, the effect of bipolar needles was evaluated on the signal intensity of theliver parenchyma. This evaluation was repeated 15 times. A calibration curve was also calculated from the in-vitro measurement of tissue temperature with an interstitial NTC sensor with dedicated data collecting software written by our team. Finally the correlation between temperature and signal intensity was prepared and during the RF ablation, the temperature map could be created in an almost real time manner.Results: Our results show an exponential calibration curve for sensors and a linear reduction of the signal intensities during the RF procedure.Conclusion: We introduce a method for calibration of the MRI signal intensity with tissue temperature between alternative RF pulses. This method brings MR monitoring as the practical method in clinical use. By this innovative technique it is possible for all the hospitals and clinics to use their routine MR scanner for monitoring this ablative technique without any additional hardware.