4Marro B. Valery CA, Bitard A, et al. Intracranial aneurysms on CTA:demonstration using a transparency volume rendering technique. J Comp Assist Tomog,2000,24:90.
5Rankin SC. Spiral CT:vascular appilcation. Euro J Radiol,1998,28 : 18.
6Rubin GD, shiau MC, schmidt A J, et al. Computed tomographic angiography: historical perspective and new state of the art using multi detector row helical computed tomography. J Comp Assist tomo, 1999,23:583.