DIFFUSION-WEIGHTED MR-IMAGING - NAVIGATED MULTISHOT SE EPI TECHNIQUE FOR CLINICAL USE

Purpose: Evaluation of a navigated multi-shot SE EPI sequence for rout ine clinical use in MR diffusion imaging, Methods: We compared a multi -shot SE EPI sequence with the conventional SE sequence as well as wit h a single-shot SE EPI sequence on a standard 1.5 Tesla MR-scanner (AC S-NT, Philips Medical Systems) with a conventional gradient system (10 mT/m). Image quality and the reproducibility of the apparent diffusio n coefficient were analysed with phantoms and with healthy volunteers. The diffusion coefficients of different brain areas were determined i n a group of twenty volunteers. Results: The multi-shot SE EPI sequenc e showed considerably shorter measurement times and smaller motion art ifacts than the SE sequence and was less sensitive to susceptibility a rtifacts than the single-shot version. The reproducibility of the diff usion coefficients was better than 10%. Conclusion: The navigated mult i-shot SE technique is more practicable and meaningful than the SE and the single-shot SE EPI techniques on a standard 1.5 Tesla MR-scanner with a conventional gradient system. In our opinion it is now the best method for diffusion imaging and should be preferred in clinical use. The determination of diffusion coefficients yields reliable results a nd characteristic values for different tissue can be obtained.