Conclusions In order to reduce the setup errors, CT scan needs not only a reference marker as close as possible to the center of the tumor, but also a reliable and accurate approach for postural fixation.%目的:利用CBCT数据分析研究宫颈癌内外照射中的摆位误差以指导临床工作.方法选取2015年3—6...
Abe et al. showed that dicentric formation was significantly increased in peripheral blood lymphocytes after a single CT scan (mean: 24.24 mSv) [5]. However Qiu et al. [6] have published that patients treated with IMRT or RapidArc in the pelvic region are not at additional risk when using...
In oral and maxillofacial surgery, a preoperative-full-head-scan is required for treatment planning purposes. Orthognathic patients are traditionally referred to radiology departments for a head CT scan. However, state-of-the-art dental-CBCT-scanners, equipped with large detectors and/or stitching ...
The patient also underwent CBCT scans on a Varian On‐Board Imager (OBI) after 40Gy dose delivery and a re‐planning CT scan (CTrepl). We performed a B‐Spline intensity based deformable registration between CTsim and CBCT with the in‐house software Plastimatch. The output deformation field...
探讨低剂量口腔CBCT检查中耳鼻喉相关组织的表现.docx,锥形束CT(cone beam computed tomography,CBCT)检查是以锥形X射线束围绕受检者受检部位旋转1周后成像的方法。通过锥形束扫描方式避免了周围结构重叠的影响,提高了三维空间分辨率,同时大大减少了扫描剂量,且明显低
The time needed for a full scan is typically under one minute and the radiation dosage is up to a hundred times less than that of a regular CT scanner.Figure Picture of Smart CBCTSince the COVID-19 virus outbreak in December 2019, the disease has spread to almost 100 countries around ...
& Razi, S. Comparison of the Hounsfield unit in CT scan with the gray level in cone-beam CT. J. Dent. Res. Dent. Clin. Dent. Prospects 13, 177–182. https://doi.org/10.15171/joddd.2019.028 (2019). Article PubMed PubMed Central Google Scholar Parsa, A. et al. Influence of ...
Two clinical target volumes (CTVs) were delineated, CTV1 including the prostate and seminal vesicles and CTV2 including the prostate only. PTVs were generated from the CTVs by adding a 1 cm margin in all directions, except for the posterior direction, where 5 mm were added. The total dose...
Many methods for correcting CBCT images with high quality have been proposed to produce quantitative CBCTs in the radiation therapy field, which do not require a calibration phantom during an object scan. These methods can be classified as hardware corrections such as anti-scatter grids, and model...
方法用已知体积的硬壁水模体和软壁水模体模拟膀胱。FBCT由2排Hispeed dual CT、64排Lightspeed VCT螺旋CT扫描,各自据螺距或床速分别扫描。CBCT据曝光条件分别pelvis、pelvis spotlight、higll quality head扫描。每种扫描5次后于TPS重建分析体积差异并与真实值对比,对......