6Lee Jh,et al. Operator-dependent techniques for graded compression sonography to detect the appendix and to diagnose acute appendicitis. Am J Roentgenol, 2005,184 (1) : 91-97.
7Rettenbacher T,et al. Ovoid shape of the vermiform appendix:a eriterion to exelude aeute appendieitis - evaluation with US. Radiology, 2003,226 (1) : 95-100.
8Wiersma F,et al. US features of the normal appendix and surrounding area in children. Radiology, 2005 : 1018-1022.
9Rioux M,HK Lim,et al. Sonographic detection of the normal and abnormal appendix. Am J Roentgenol, 1992,158(4) : 773-778.
10Jan YT, et al. Visualization and pattern of normal appendix on multidetector computed tomography by using multiplanar reformation display. Journal of Computer Assisted Tomography, 2005,29(4):446-451.
