Abstract：
:Current MRI nonuniformity correction techniques are reviewed and investigated. Many approaches are used to remedy this artifact, but it is not clear which method is the most appropriate in a given situation, as the applications have been with different MRI coils and different clinical applications. In this work four widely used nonuniformity correction techniques are investigated in order to assess the effect on tumor response measurements (change in tumor volume over time): a phantom correction method, an image smoothing technique, homomorphic filtering, and surface fitting approach. Six brain tumor cases with baseline and follow-up MRIs after treatment with varying degrees of difficulty of segmentation were analyzed without and with each of the nonuniformity corrections. Different methods give significantly different correction images, indicating that rf nonuniformity correction is not yet well understood. No improvement in tumor segmentation or in tumor growth/shrinkage assessment was achieved using any of the evaluated corrections.
journal_name
Med Physjournal_title
Medical physicsauthors
Velthuizen RP,Heine JJ,Cantor AB,Lin H,Fletcher LM,Clarke LPdoi
10.1118/1.598357subject
Has Abstractpub_date
1998-09-01 00:00:00pages
1655-66issue
9eissn
0094-2405issn
2473-4209journal_volume
25pub_type
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