重建耻骨联合三维结构用于活体年龄推断的技术方法

Age assessment by three-dimensional reconstructions of pubis symphysis via magnetic resonance imaging

目的建立基于MRI成像的快速耻骨联合三维结构重建技术方法。方法利用3.0 T超导磁共振仪对成年男性志愿者骨盆进行T1小角度快速激发3D梯度回波序列扫描,进行二值化阈值分割、区域增长提取骨盆软组织图像;运算获得耻骨联合三维结构模型雏形,经逆向工程软件降噪处理建立耻骨联合三维结构模型,并与耻骨CT扫描三维结构重建模型进行比较。结果耻骨联合面沟嵴、下端、腹侧缘(斜面)、背侧缘(斜面)、耻骨结节等结构显示完整,无明显噪点,与CT扫描三维重建模型吻合较好。结论 MRI扫描成像可实现快速有效的耻骨联合三维结构重建,可为法医活体年龄推断提供安全无辐射作用的三维可视化影像学技术方法。

Objective To establish a method of quick three-dimensional（3D） reconstruction of pubic symphysis based on magnetic resonance imaging. Methods The pelvis images of adult male were generated on a 3.0 T scanner using a T1 Gradient Echo FLASH-3D（T1-FL3D） sequence and imported the images into medical image control system. Segmentation of binaryzation threshold was conducted and pelvic soft tissue image was extracted by regional growth, 3D structure model of pubic symphysis was obtained by Boolean operation. The 3D structure model of pubic symphysis was established by the noise reduction of reverse engineering software. And compared with the 3D reconstruction model pubic bone CT scan. Results The morphological characters of the MRI pubic symphysis 3D model, such as the ridges and furrows on the symphysial surface, lower extremity, dorsal margin（beveling）, margin（beveling） and pubic tubercle, were highly consistent with the morphological characters of the 3D model established by CT scan. Conclusion MRI scan can be used to reconstruct the 3D structure of pubic symphysis quickly and effectively, and it can provide a safe radiation-free 3D visualization imaging technique for forensic age estimation for the living.