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Chhatwal J, Alagoz O, Lindstrom MJ, Kahn CE Jr, Shaffer KA, Burnside ES.Chhatwal J, et al.AJR Am J Roentgenol. 2009 Apr;192(4):1117-27. doi: 10.2214/AJR.07.3345.AJR Am J Roentgenol. 2009.PMID: 19304723Free PMC article.