外质量的高密度物体会影响视野内高密度物体的体积
Fernanda Coelho-Silva1, Deivi Cascante-Sequeira1, Marcela Tarosso Réa1
1Division of Oral Radiology, Department of Oral Diagnosis, Piracicaba Dental School, University of Campinas, Piracicaba 13414-903, Brazil.
Dento maxillo facial radiology
|January 15, 2024
概括
在形光束CT (CBCT) 成像中,高密度物体在视野外 (FOV) 的数量和位置会影响FOV内的物体的测量体积. 这种体积变化 (VA) 根据材料和CBCT系统而异.
科学领域:
- 牙科成像 牙科成像 牙科成像
- 放射学 放射学是一门学科.
- 医学物理 医学物理
背景情况:
- 形光束CT (CBCT) 在牙科和医学中广泛使用.
- 准确的体积测量对于诊断和治疗规划至关重要.
- 由高密度物体引起的人工物质会影响图像质量和准确性.
研究的目的:
- 调查外部高密度物体的存在和数量如何影响CBCT中视野 (FOV) 内的物体的测量体积.
- 评估不同材料 (-,,) 和它们的空间布局对体积精度的影响.
主要方法:
- 创建了五个实验组,使用不同数量和位置的气 (0,1前,1后,2后,3前/后) 制成-,或.
- 使用OP300和X800系统进行CBCT扫描,这些外部物体和中央高密度圆柱体.
- 通过将细分体积与物理体积进行比较来计算体积变化 (VA),并使用重复测量ANOVA进行分析.
主要成果:
- 材料,物体组合和它们的相互作用显著影响了CBCT系统上的体积测量.
- 在OP300系统上,增加的外部物体数量减少了VA,特别是对于-.
- 在X800系统上,更多的外部物体倾向于增加VA,而石显示的易感性较小.
结论:
- 外部高密度物体显然会影响CBCT视野内的物体的体积精度.
- 这种体积变化的程度取决于材料组成,数量和外部物体的位置,以及使用的特定CBCT系统.
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