Cavalcanti M G P, Rocha S S, Vannier M W
Department of Radiology, College of Dentistry, University of São Paulo,São Paulo, Brazil.
Dentomaxillofac Radiol. 2004 May;33(3):170-6. doi: 10.1259/dmfr/13603271.
This study was designed to determine the precision and accuracy of anthropometric measurements using three-dimensional computed tomography (3D-CT) volume rendering by computer systems for craniofacial clinical applications, and to compare the craniometric landmarks using bone and soft tissue protocols.
The study population consisted of 13 cadaver heads that were examined with spiral CT. The archived CT data were transferred to a workstation, and 3D-CT volume rendered images were generated using computer graphics tools. Linear measurements (n = 10), based upon conventional craniometric anatomical landmarks (n = 08), were identified in 2D-CT and in 3D-CT images by two radiologists twice each independently, and then performed by 3D-CT imaging using a computer graphics systems using bone and soft tissue protocols. In total, 520 imaging measurements were made. The soft tissues were subsequently removed from the cadaver heads and the measurements were repeated using an electromagnetic 3 Space trade mark digitizer.
The results demonstrated no statistically significant difference between interobserver and intraobserver measurements or between imaging and physical measurements in both 3D-CT protocols. The standard error was found to be between 0.45% and 1.44% for all the measurements in both protocols, indicating a high level of precision. Furthermore, there was no statistically significant difference between imaging and physical measurements (P > 0.01). The error between the mean actual and mean 3D-based linear measurements was 0.83% for bone and 1.78% for soft tissue measurements, demonstrating high accuracy of both 3D-CT protocols.
3D-CT volume rendering images using craniometric measurements can be used for anthropological studies involving craniofacial applications.
本研究旨在确定计算机系统利用三维计算机断层扫描(3D-CT)容积再现技术进行颅面临床应用人体测量的精度和准确性,并比较使用骨骼和软组织方案的颅骨测量标志点。
研究对象包括13个尸体头部,均进行了螺旋CT检查。将存档的CT数据传输到工作站,使用计算机图形工具生成3D-CT容积再现图像。两名放射科医生分别两次独立在二维CT和三维CT图像中,根据传统颅骨测量解剖标志点(共8个)确定线性测量值(共10个),然后使用计算机图形系统通过骨骼和软组织方案对三维CT成像进行测量。总共进行了520次成像测量。随后从尸体头部移除软组织,并使用电磁3Space商标数字化仪重复测量。
结果表明,在两种三维CT方案中,观察者间和观察者内测量之间或成像测量与物理测量之间均无统计学显著差异。两种方案中所有测量的标准误差在0.45%至1.44%之间,表示精度较高。此外,成像测量与物理测量之间无统计学显著差异(P>0.01)。骨骼测量的平均实际线性测量值与基于三维的平均线性测量值之间的误差为0.83%,软组织测量为1.78%,表明两种三维CT方案均具有较高的准确性。
使用颅骨测量的三维CT容积再现图像可用于涉及颅面应用的人类学研究。