Sato Y, Shiraga N, Nakajima S, Tamura S, Kikinis R
Division of Functional Diagnostic Imaging, Biomedical Research Center, Osaka University Medical School, Suita, Japan.
J Comput Assist Tomogr. 1998 Nov-Dec;22(6):912-7. doi: 10.1097/00004728-199811000-00014.
The purpose of our study was to demonstrate a new visualization method (local maximum intensity projection; LMIP) that can clearly depict densitometric as well as geometric information in vascular visualization from 3D data such as obtained from MR and CT angiography.
LMIP is an extended version of maximum intensity projection (MIP). However, LMIP differs from MIP in that the latter method selects the maximum value along an optical ray, whereas LMIP selects the first local maximum value encountered that is larger than a preselected threshold value along an optical ray from a viewpoint in the viewing direction.
Examples are presented in which LMIP is used to visualize renal vessels from CT angiography data and cerebral vessels in the vicinity of an aneurysm from phase-contrast MR angiography data. We demonstrate that LMIP can clearly depict geometric information, as shaded surface display does, and densitometric information, as is done by volume rendering, in a straightforward and objective manner.
我们研究的目的是展示一种新的可视化方法（局部最大强度投影；LMIP），该方法能够清晰地描绘从磁共振血管造影（MR angiography）和计算机断层血管造影（CT angiography）等3D数据进行血管可视化时的密度信息以及几何信息。
LMIP是最大强度投影（MIP）的扩展版本。然而，LMIP与MIP的不同之处在于，后者沿着光线选择最大值，而LMIP是从观察方向的一个视点沿着光线选择遇到的第一个大于预选阈值的局部最大值。
给出了使用LMIP从CT血管造影数据可视化肾血管以及从相位对比MR血管造影数据可视化动脉瘤附近脑血管的示例。我们证明，LMIP能够以直观且客观的方式，像表面阴影显示那样清晰地描绘几何信息，像容积再现那样描绘密度信息。
