Katsumata Akitoshi, Hirukawa Akiko, Okumura Shinji, Naitoh Munetaka, Fujishita Masami, Ariji Eiichiro, Langlais Robert P
Department of Oral Radiology, Asahi University School of Dentistry, Gifu, Japan.
Oral Surg Oral Med Oral Pathol Oral Radiol Endod. 2007 Dec;104(6):829-36. doi: 10.1016/j.tripleo.2006.12.005. Epub 2007 Apr 20.
An in vitro study was designed to investigate the influence of projection data discontinuity-related artifacts in limited-volume cone-beam computerized tomography (CBCT) imaging of the jaws.
Test objects were positioned in 4 patterns in a water-filled phantom as follows: bimandible and vertebrae, bimandible, left mandible and vertebrae, and left mandible. The CT imaging of the left molar region was performed using image intensifier (II)- and flat panel detector (FPD)-based CBCT scanners. The CT value of the mandible and the adjacent soft tissue region were analyzed for density by means of an 8-bit grayscale.
The effects of artifacts were scored as the difference in relative density between the lingual and buccal soft tissue. The intensity of artifacts increased when more objects were presented outside the area being imaged. Fewer artifacts were noted in images produced by the particular FPD CBCT used in this investigation.
The CBCT system using an FPD resulted in fewer artifacts than the CBCT system using an II in this particular study.
设计一项体外研究，以调查颌骨有限体积锥形束计算机断层扫描（CBCT）成像中投影数据不连续相关伪影的影响。
测试对象在充满水的体模中以4种模式放置如下：双侧下颌骨和椎骨、双侧下颌骨、左侧下颌骨和椎骨以及左侧下颌骨。使用基于影像增强器（II）和平板探测器（FPD）的CBCT扫描仪对左侧磨牙区域进行CT成像。通过8位灰度分析下颌骨及相邻软组织区域的CT值以确定密度。
将伪影的影响评定为舌侧和颊侧软组织之间相对密度的差异。当成像区域外出现更多物体时，伪影强度增加。在本研究中使用的特定FPD CBCT产生的图像中观察到的伪影较少。
在本特定研究中，使用FPD的CBCT系统比使用II的CBCT系统产生的伪影更少。
