■我们开发了一种骨骼专用准直器,该准直器具有更高的灵敏度,但在用于平面骨骼闪烁显像的单光子发射计算机断层扫描(SPECT)上的分辨率略有下降,与传统的低能量高分辨率准直器相比。在这项工作中,我们研究了使用盲反卷积算法来提高骨闪烁显像平面图像分辨率的可行性。
■使用NCAT体模进行蒙特卡罗模拟,以在配备有骨骼专用准直器的临床双头SPECT扫描仪(ImagineNET632,北京新颖医疗设备有限公司)上进行骨骼闪烁显像。最大似然估计方法用于盲解卷积算法。通过比较从不同输入参数获得的去模糊图像,确定了该方法的点扩散函数(PSF)的初始估计和迭代次数。我们模拟了五个不同位置和五个不同直径的不同肿瘤,以评估初始输入的鲁棒性。此外,我们在临床SPECT扫描仪上进行了胸部体模研究.评估肿瘤和背景之间的量化的增加的对比度(CR)。
■2mmPSF内核和10次迭代在我们的系统上提供了实用且鲁棒的去模糊图像。这两个输入可以在肿瘤位置和大小方面生成鲁棒的去模糊图像,其中平均增加的CR为21.6%。幻影研究还证明了盲解卷积的能力,使用这两个输入,CR增加了17%,17%,22%,20%,直径为1厘米的病变占13%,2厘米,3厘米,4厘米,和5厘米,分别。
■使用盲解卷积算法对SPECT骨闪烁显像的平面图像进行去模糊是可行的。可以使用仿真研究来确定PSF核的适当值和盲解卷积的迭代次数。
UNASSIGNED: We have developed a bone-dedicated collimator with higher sensitivity but slightly degraded resolution on single-photon emission computed tomography (SPECT) for planar bone scintigraphy, compared with conventional low-energy high-resolution collimator. In this work, we investigated the feasibility of using the blind deconvolution algorithm to improve the resolution of planar images on bone scintigraphy.
UNASSIGNED: Monte Carlo simulation was performed with the NCAT phantom for modeling bone scintigraphy on the clinical dual-head SPECT scanner (Imagine NET 632, Beijing Novel Medical Equipment Ltd.) equipped with the bone-dedicated collimator. Maximum likelihood estimation method was used for the blind deconvolution algorithm. The initial estimation of point spread function (PSF) and iteration number for the method were determined by comparing the deblurred images obtained from different input parameters. We simulated different tumors in five different locations and with five different diameters to evaluate the robustness of the initial inputs. Furthermore, we performed chest phantom studies on the clinical SPECT scanner. The quantified increased contrast ratio (CR) between the tumor and the background was evaluated.
UNASSIGNED: The 2 mm PSF kernel and 10 iterations provided a practical and robust deblurred image on our system. Those two inputs can generate robust deblurred images in terms of the tumor location and size with an average increased CR of 21.6%. The phantom studies also demonstrated the ability of blind deconvolution, using those two inputs, with increased CRs of 17%, 17%, 22%, 20%, and 13% for lesions with diameters of 1 cm, 2 cm, 3 cm, 4 cm, and 5 cm, respectively.
UNASSIGNED: It is feasible to use the blind deconvolution algorithm to deblur the planar images for SPECT bone scintigraphy. The appropriate values of the PSF kernel and the iteration number for the blind deconvolution can be determined using simulation studies.