cbct

At first , the CBCT projection data was simulated with computer simulation technology .

首先，运用计算机仿真技术模拟出锥束CT投影数据；

The Realization of the High-Speed Data Acquisition of the CBCT System Based on LVDS Technology

基于LVDS技术的CBCT系统高速数据采集的实现

According to the characters of CBCT image , we proposed the noise variance estimation formula .

根据CBCT图像的特点，提出了适合CBCT图像的噪声方差估计公式，使其更适合CBCT图像噪声的去噪。

CBCT has great advantage over conventional radiography in the diagnosis and treatment of endodontic problems .

相对于传统的X片，CBCT在牙体牙髓病的诊断治疗中具有相当的优势。

Because of its real-time , high sensitivity , convenience of Clinical Application , CBCT imaging system is drawing more and more attention .

CBCT成像系统因实时性好、灵敏度高、使用方便等特点而越来越受到重视，并广泛应用到肿瘤精确定位系统中。

We want to use the image of the same breathing phase to reconstruct CBCT images . And this can significantly improve the image quality .

为了克服肿瘤靶区边缘模糊的问题，我们利用同一呼吸相位的图像来重建CBCT图像，能显著提高图像质量。

Hence , it can be proved that realizing CBCT in image-guided radiotherapy perfusion imaging by the proposed model was feasible .

该模型实现图像引导放疗中的锥束CT灌注成像是可行的。

Based on the characters of scattering artifacts in CBCT , a scatter correction method combining beam attenuation grid and scatter sampling is proposed .

针对锥束CT散射伪影的特点，建立了散射校正模型，提出了一种结合衰减网格与散射采样的散射校正方法。

Experimental results for a test image and clinical CBCT images show that this algorithm can suppress noise in CBCT images effectively with important structure details preserved .

对测试图像与临床CBCT图像的去噪结果表明，该算法能够在保留重要诊断细节的同时有效地抑制CBCT图像中的噪声。

Objective To study the role of KV-X CBCT on the geometricl accuracy of IMRT of nasopharyngeal carcinoma .

目的探讨KV-X线CBCT在鼻咽癌调强放射治疗位置精度保证中的应用。

RT image includes the picture obtained by imaging device ( CBCT ), digitally reconstructed radiographs ( DRR image ) and so on .

RT图像包括成像设备（如CBCT）所得到的图像及数字化重建放射图像（DRR图像）等。

Objective : This work was to analyze the set-up errors in image guided IMRT for tumors using the cone-beam computed tomography ( CBCT ) .

目的探讨锥形束CT用于调强放疗分次间摆位误差测量。

Compared with usual fan-beam and parallel-beam CT , CBCT has numerous advantages , such as higher spatial resolution , faster scan speed , and etc.

相比通常的扇束和平行束CT重建，锥束CT有诸多优点（如空间分辨率高，扫描速度快等）。

Imaging methods is the use of Micro CT , CBCT , spiral CT and panoramic photography and other equipment scanning and measuring the teeth or dental arch .

影像学方法是采用MicroCT、牙科CT、螺旋CT和曲面断层摄影等设备扫描牙齿或牙弓，在计算机上获取人牙的图像后进行测量。

CBCT can clearly display external and internal resorption , identify the scope and degree of resorption three-dimensionally , help to determine treatment plan for root resorption .

CBCT可以清晰显示对牙内、外吸收病变，明确牙齿颊舌向吸收的范围及程度，有助于确定牙根吸收后的治疗规划。

CBCT images have the advantages of good real-time , high sensitivity , and convenience . Their superiority is more prominent when they are registered and fused with Planning CT images .

通常，CBCT兼具实时性好、灵敏度高、使用方便等优点，与计划CT图像配准融合后可更加充分地发挥上述优势。

Considering the measurement accuracy , operability , applicability and cost , etc. , we believe that the CBCT is more suitable for dental dentition morphological measurements in vivo . 2 .

结论1.根据四种影像学方法的测量精度、可操作性、适用性及成本等方面，笔者认为牙科CT较适合对人体全牙列进行形态学测量研究。

This method can preserve the edges information of CBCT images , reduce the denoising artifacts , achieve higher PSNR ( Peak Signal to Noise Ratio ), and provide a better vision effect . 2 .

该方法可以有效地保留CBCT图像中的边缘信息，减少去噪伪影，并能得到更高的峰值信噪比，进而有更好的视觉效果。

CBCT and Planning CT elastic registration based on attribute vector ( 1 ) The existence and corruption of noises in CBCT images is one of the main interfering factors for the accuracy of registration .

基于特征向量的CBCT图像与计划CT图像的多模弹性配准（1）CBCT图像中的噪声是影响CBCT图像与计划CT图像配准结果准确性的主要因素之一。

Because the projection slice data in the same respiratory phase is very little , Shannon formula can not be meted . We apply the compressed sensing theory to the CBCT image reconstruction algorithm , and give the experimental result .

针对同一呼吸相位的投影切片数据量少、不能满足传统的Shannon公式问题，我们提出了将压缩感知理论应用到CBCT图像重建算法。

There are several factors affecting the CBCT image quality : truncated projection , beam hardening , the patient physiological movement , the compensation and gain correction of detector , the speckle , the misaligned CBCT geometric structures and so on .

CBCT图像与CT图像相比质量较差，影响CBCT图像质量的主要因素有：截断伪影、射线硬化、病人的生理运动、探测板的补偿和增益校正、散斑、CBCT几何结构未对齐等。

Because of the complexity of the formative factors of artifacts in CBCT , this thesis investigates scattering artifact and metal artifact with Monte Carlo method , and the formats of artifacts under single factors are given after physics calculation and digital phantoms simulation .

由于锥束CT伪影形成原因复杂，本文运用蒙特卡罗方法对散射伪影和金属伪影进行研究，通过物理计算和数字体模仿真，给出单因素的伪影表现形式。