摘要
开放式肝脏肿瘤切除手术是治疗肝脏肿瘤的最有效方法,基于双目结构光的术中肝脏表面三维重建对肿瘤的精确定位起到至关重要的作用。但由于手术环境光照和双目相机采集图像的位置等因素,将造成相机拍摄的图像出现局部亮度饱和问题,进而导致肝脏表面三维重建缺失。为此,本文提出基于不同反射率区域分割投影算法制定的自适应最佳条纹光栅的方法来解决该问题。先建立肝脏表面光照的物理模型和双目系统下的肝脏表面光照示意图并分析肝脏表面局部亮度饱和的影响。接着,利用肝脏表面不同位置的反射率不同,进行区域划分,根据不同反射率的区域分割投影算法来计算自适应最佳条纹光栅的强度,实现肝脏表面的分区投射。然后,将左、右相机图像中的饱和点转换到投影仪投射的条纹图像中并通过局部亮度饱和实验来验证本文提出的方法对克服肝脏表面局部亮度饱和问题的有效性。最后,通过猪肝实验结果表明:采用本文提出的方法后,三种不同手术状态下因局部亮度饱和而导致猪肝三维重建表面的缺失比率分别从1.1%、2.9%和1.4%降至0%,并且猪肝表面三维重建精度达到0.75 mm。本文的方法基本可以满足医生提出的术中肝脏表面三维重建精度1 mm以内并且重建表面无缺失的要求。
An open resection of liver tumors is the most effective method for their treatment.The intraoperative three-dimensional(3D)reconstruction of liver surface based on binocular structural light plays an important role in the accurate localization of liver tumors.However,due to factors such as illumination in the surgical environment and the location of images captured by the binocular camera,a local brightness saturation occurs in the captured images,leading to hindrance in the three-dimensional reconstruction of the liver surface.To solve this problem,an adaptive optimal fringe grating based on the segmentation projection algorithm of different reflectivity regions is proposed in this paper.First,a physical model and a sketch of illumination on the liver surface under binocular system were established,and the influence of local brightness saturation on the liver surface was analyzed.The region was then divided according to the different reflectivity of the liver surface.The intensity of the adaptive optimal fringe grating was calculated according to the region segmentation projection algorithm of different reflectivity,so as to achieve the partition projection of the liver surface.The saturation points of the left and right camera images were transferred to the streaks cast by the projector.The effectiveness of the proposed method to overcome the local brightness saturation of the liver surface was verified by the local brightness saturation experiment.Finally,the experimental results of porcine liver showed that the deletion rate of porcine liver 3D reconstruction surface decreased from 1.1%,2.9%,and 1.4%to 0%,respectively,under three different operating conditions due to local brightness saturation,and the accuracy of porcine liver 3D reconstruction reached 0.75 mm.The method described in this paper can essentially meet the requirements of doctors,including the intraoperative 3D reconstruction accuracy of liver surface to be less than 1 mm with no defects in the reconstructed surface.
作者
陈龙
王文聪
张峰峰
孙立宁
CHEN Long;WANG Wen-Cong;ZHANG Feng-Feng;SUN Li-Ning(School of Mechanical and Electrical Engineering,Soochow University,Suzhou 215006,China;Collaborative Innovation Center of Suzhou Nano Science and Technology,Soochow University,Suzhou 215123,China)
出处
《光学精密工程》
EI
CAS
CSCD
北大核心
2021年第11期2590-2602,共13页
Optics and Precision Engineering
基金
国家重点研发计划项目(No.2018YFB1307700)。
关键词
肝脏
结构光
亮度饱和
投影
区域分割
liver
structured light
brightness saturation
projection
regional segmentation
