VISUALIZATION OF MAGNETIC RESONANCE-COMPATIBLE NEEDLES AT 1.5 AND 0.2TESLA

Purpose: For two types of passively visualizable magnetic resonance (M R)-compatible needles, the size of susceptibility artifacts was invest igated at 0.2 and 1.5 Tesla (T) and assessed regarding their suitabili ty for needle visualization. Methods: Phantom trials were performed us ing T1-weighted spin echo (SE), turbospin echo (TSE) and gradient echo (GE) sequences and different angles beta between the needles and the main magnetic field (B-0). Results: Depending on the needle angle beta and the applied pulse sequence, we found artifact diameters of 0-9.7 mm employing SE, of 1.7-9.4 mm employing TSE, and of 1.4-20.6 mm emplo ying GE at 1.5 T. At 0.2 T, we found artifact diameters of 0-5.7 mm em ploying SE, of 0-6.3 mm employing TSE, and of 0-11.3 mm employing GE. Conclusion: Comparing artifact sizes at 1.5 T and 0.2 T, low field str ength is superior for passive visualization of the needles tested-espe cially if GE imaging is performed.