Helium CT: Monte Carlo simulation results for an ideal source and detector with comparison to proton CT.
Helium CT: Monte Carlo simulation results for an ideal source and detector with comparison to proton CT.
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DOI：
10.1002/mp.12942
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发表时间：
2018-07
期刊：
影响因子：
3.8
通讯作者：
Seco J
中科院分区：
文献类型：
--
作者：
Piersimoni P;Faddegon BA;Méndez JR;Schulte RW;Volz L;Seco J
评价模拟氦CT（HeCT）与质子CT（pCT）重建图像的相对阻止本领和空间分辨率的准确性。使用TOPAS工具进行了Monte Carlo（MC）研究，以比较低通量HeCT与pCT的相对阻止本领（RSP）重建和空间分辨率的准确性，两者均使用200 MeV/u粒子。一个理想的设置，包括一个平面光束源和一个完全吸收的能量范围检测器的实现，以估计理论上最好的可实现的RSP精度的校准和重建方法目前用于pCT。成像的体模包括具有不同材料、尺寸和位置的插入物的圆柱形水体模、具有包含高对比度线对的模块（CTP 528）的Catphan体模和具有不同RSP的圆柱形插入物的模块（CTP 404），以及体素化的10岁女性体模。还计算了圆柱形水体模的剂量。研究了除CTP 528模块外的所有体模的RSP准确度。后者用于估计空间分辨率，评估为10%时的调制传递函数（MTF）。对于具有不同插入物的水体模，HeCT实现了低于0.5%的总体误差，在所有情况下均优于pCT，在某些情况下为3倍。重建CTP 404模块中的插入物，HeCT的平均RSP准确度为0.3%，pCT为0.2%。解剖结构（大脑、骨骼、气腔等）在数字化头部模型中，可很好地识别，HeCT和pCT均未观察到伪影。三个主要的组织材料（软组织，大脑和颅骨）是很好地识别重建的RSP体积分布与两种成像模式。使用360个投影角度，HeCT的空间分辨率为4 lp/cm，pCT的空间分辨率为3 lp/cm。通常，空间分辨率随着投影角度的数量而增加，并且对于相同数量的投影，HeCT的空间分辨率总是高于pCT。当进行HeCT和pCT扫描以在体模中输送相同剂量时，HeCT的分辨率高于pCT。MC模拟用于比较HeCT和pCT图像重建。与pCT相比，HeCT图像具有相似或更好的RSP准确性和更高的空间分辨率。氦离子成像的潜力的进一步调查是必要的。
To evaluate the accuracy of relative stopping power and spatial resolution of images reconstructed with simulated helium CT (HeCT) in comparison to proton CT (pCT). A Monte Carlo (MC) study with the TOPAS tool was performed to compare the accuracy of relative stopping power (RSP) reconstruction and spatial resolution of low-fluence HeCT to pCT, both using 200 MeV/u particles. An ideal setup consisting of a flat beam source and a totally absorbing energy-range detector was implemented to estimate the theoretically best achievable RSP accuracy for the calibration and reconstruction methods currently used for pCT. The phantoms imaged included a cylindrical water phantom with inserts of different materials, sizes, and positions, a Catphan phantom with a module containing high-contrast line pairs (CTP528) and a module with cylindrical inserts of different RSP (CTP404), as well as a voxelized 10-year-old female phantom. Dose to the cylindrical water phantom was also calculated. The RSP accuracy was studied for all phantoms except the CTP528 module. The latter was used for the estimation of the spatial resolution, evaluated as the modulation transfer function (MTF) at 10%. An overall error under 0.5% was achieved for HeCT for the water phantoms with the different inserts, in all cases better than that for pCT, in some cases by a factor 3. The inserts in the CTP404 module were reconstructed with an average RSP accuracy of 0.3% for HeCT and 0.2% for pCT. Anatomic structures (brain, bones, air cavities, etc.) in the digitized head phantom were well recognizable and no artifacts were visible with both HeCT and pCT. The three main tissue materials (soft tissue, brain, and cranium) were well identifiable in the reconstructed RSP-volume distribution with both imaging modalities. Using 360 projection angles, the spatial resolution was 4 lp/cm for HeCT and 3 lp/cm for pCT. Generally, spatial resolution increased with the number of projection angles and was always higher for HeCT than for pCT for the same number of projections. When HeCT and pCT scan were performed to deliver the same dose in the phantom, the resolution for HeCT was higher than pCT. MC simulations were used to compare HeCT and pCT image reconstruction. HeCT images had similar or better RSP accuracy and higher spatial resolution compared to pCT. Further investigation of the potential of helium ion imaging is warranted.
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影响因子：
3.5
作者：
Collins-Fekete, Charles-Antoine;Volz, Lennart;Seco, Joao
通讯作者：
Seco, Joao
影响因子：
1.8
作者：
Johnson RP;Bashkirov V;DeWitt L;Giacometti V;Hurley RF;Piersimoni P;Plautz TE;Sadrozinski HF;Schubert K;Schulte R;Schultze B;Zatserklyaniy A
通讯作者：
Zatserklyaniy A
影响因子：
3.8
作者：
Giacometti, Valentina;Bashkirov, Vladimir A.;Schulte, Reinhard W.
通讯作者：
Schulte, Reinhard W.
影响因子：
3.8
作者：
Penfold, S. N.;Schulte, R. W.;Rosenfeld, A. B.
通讯作者：
Rosenfeld, A. B.
影响因子：
3.1
作者：
Hansen, David C.;Seco, Joao;Landry, Guillaume
通讯作者：
Landry, Guillaume