Antje Kickhefel1,
Christian Rosenberg2,3, Joerg Roland4, Patrick Gross4,
Fritz Schick5, Norbert Hosten2, Rares Salomir6
1Diagnostic
& Interventional Radiology, Eberhard-Karls-University Tbingen, Tbingen,
Baden-Wrttemberg, Germany; 2Diagnostic Radiology &
Neuroradiology, Ernst-Moritz-Arndt-Universitt Greifswald, Greifswald,
Germany; 3Diagnostic Radiology & Neuroradiology, Greifswald,
Germany; 4Siemens Healthcare, Erlangen, Bavaria, Germany; 5Diagnostic
& Interventional Radiology, Eberhard-Karls-University Tbingen, Tbingen,
Baden-Wrtemberg, Germany; 6Radiology, University Hospitals of
Geneva, Geneva, Switzerland
A novel implementation of the reference-less PRFS method for MR thermometry is described here. The method is based on near-harmonic reconstruction of GRE 2D phase background and enables no-user-interaction temperature calculations over the whole liver. Alternatively, it may be used with an arbitrarily thin border (unheated). The current implementation offers high flexibility and robustness under clinical workflow. The actual reference-less calculations were compared to the standard time-referenced respiratory triggered MR thermometry, using clinical data from a liver LITT ablation protocol in 6 patients. The average precision of baseline measurements using the standard reference-method was 4C, the reference-less calculation greatly improved this precision by reducing it to 0.5C.