1.Observation of CT-MRI image fusion in postoperativeprecise radiotherapy for gliomas
Rong HUANG ; Hui WU ; Xiaoxu LU ; Jing XU ; Yanling WANG ; Dingjie LI ; Zhiyao CHENG
Chinese Journal of Radiation Oncology 2017;26(2):192-196
Objective To investigate the value of computed tomography (CT)-magnetic resonance imaging (MRI) image fusion in target volume delineation of postoperative precise radiotherapy for gliomas.Methods Thirty-six patients newly diagnosed with gliomas were enrolled and received postoperative intensity-modulated radiotherapy.Landmark (L) combined with manual fusion (M) and maximization of mutual information (MI) was used for image fusion.Target volume and organs at risk were delineated based on CT images and fused images,respectively.Comparison of the volume was made by pairwise t test.The distance from a landmark on CT image to the corresponding one on MRI image was calculated.The volume method and geometric center method were used to calculate the degree of volume overlap and changes in central positions after image fusion.Results The L+M+MI method achieved a high registration accuracy in image fusion,with a registration error less than 2 mm.In patients with grade Ⅲ-V gliomas,the CT images yielded significantly smaller gross tumor volume (GTV) and clinical target volume (CTV) than the MRI images (74.62±46.91 vs.105.99±58.86 cm3,P=O.042;304.03± 130.05 vs.387.94± 150.12 cm3,P=0.040).After image fusion,the smallest change in central position occurred in the chiasma (1.32± 1.42 mm),and the largest change occurred in CTV (7.99± 11.06 mm),followed by GTV and the brain stem.Conclusions CT-MRI image fusion helps to reduce the uncertainty of target volume delineation in patients with gliomas,especially in those with edema and residual tumor after surgery.
2.Application of auto-importing of CT images and structures into treatment planning system based on UiBot software
Bing LI ; Zhiyao CHENG ; Wei GUO ; Ronghu MAO ; Zhaoyang LOU ; Xiuyan CHENG ; Hong GE
Chinese Journal of Radiation Oncology 2021;30(11):1178-1182
Objective:To build a systemic and automatic importing scheme for importing CT images and structures into the treatment planning systems (TPSs) of Eclipse and Monaco.Methods:Based on two TPSs of Eclipse and Monaco, the files of CT images and structures were automatically transported from OAR auto-delineation system to the importing directory of these two TPSs using batch script in Windows system. Following the standard importing procedures of these two TPSs, the automatically importing script of CT images and structures were developed using the application of UiBot. Finally, the CT images and structures were imported into these two TPSs opportunely.Results:By comparing the importing time using script and manual methods, the script not only achieved auto-importing CT images and structures into TPSs, but also yielded almost the same efficiency to manual method. The number of imaging layers in most patients was between 130 and 180, and the average manual and automatic importing time within this interval was 76 s and 75 s.Conclusions:Automatic scripts can be developed by using the automation function of UiBot combined with the actual problems of radiotherapy and repeated workflow. The efficiency of radiotherapy work can be significantly improved. Manual and time costs can be saved. It provides a novel alternative for the automation of radiotherapy procedures.
3.Research Progress of Toll-like Receptors and Cerebral Ischemia
Sujun ZHANG ; Yuzhe GAO ; Zhiyao WEI ; Changhe LAI ; Junwen CHENG ; Xiaohui DING
Journal of Shenyang Medical College 2016;18(4):305-308
Cerebrovascular disease is one of the main diseases that threaten human health and life,and the age of onset become younger and younger. Research shows that Toll-like receptors (TLRs) express in brain, have effects on neurons, play an important role in the occurrence and development of cerebral ischemia and secondary cerebral injury.It is clear that TLR2, TLR3, TLR4, TLR7 and TLR9 have influence on occurrence and development of cerebral ischemia. This is crucial for understanding the relationship between immune inflammation and nerve regeneration, and improving clinical treatment.
4.Clinical application of MdaccAutoPlan in the planning of nasopharyngeal carcinoma with intensity modulated radiotherapy
Zhiyao CHENG ; Dingjie LI ; Hui WU ; Rong HUANG ; Xiaofang YIN ; Feng WANG
Chinese Journal of Radiological Medicine and Protection 2018;38(4):285-290
Objective To compare the MdaccAutoPlan (MDAP)software with Manual planning in intensity modulated radiotherapy (IMRT) planning for nasopharyngeal carcinoma (NPC) patients.Methods A total of 20 newly diagnosed NPC patients were enrolled and their IMRT plans were designed with MDAP software and manually,respectively with identical field angle,optimization parameters and other planning requirements.Dosimetric differences and planning efficiency were compared for these two planning method.Results The PGTV Dgs%,PGTV D PTV1 Dgs%,PTV1 D PTV2 D98%,PTV2 D of plans generated from MDAP were reduced by 2.5%,0.3%,0.1%,0.5%,0.6%,1.0%,respectively,compared with those in plans generated manually.The D2% of the PGTV,PTV1,PTV2 in MDAP plans were increased by 1.7%,1.5%,0.6% compared with those in manual plans,respectively.There were significant differences observed in the PGTV D9s%,PGTV D2% and PTV2 Dg8% between these two planning method (t =5.519,6.701,0.937,P < 0.05).The D50% of right parotidand left parotid,the D and D of the spinal cord in MDAP plans were reduced significantly by 24.8%,27.7%,11.4%,14.0%,respectively,compared with those in manual plans (t =5.447,5.375,6.786,3.810,P < 0.05).The dose of both lens increased significantly by 65.0% and 19.3%,respectively,in MDAP plans compared with Manual plans (t =9.863,3.440,P < 0.05).There was no significant dosimetric difference observed in opticnerve,opticchiasm and brainstem between these two planning method.The dose distribution of post neck in MDAP plans were better than those in manual plans.The dose-volume histogram curves of planning target volume,brainstem and spial cord in the manul plans were higher than those in the MDAP plans.The labor time of MDAP planning was reduced by 54.4% compared with Manual planning,while computer working time was increased by 34.4% with MDAP planning compared with Manual planning.Conclusions MDAP planning is clinically valualbe in its applicaion for a NPC IMRT planning with a better sparing for OARs,a decreased planning time and improvement on planning efficiency compared with manual planning.
5.Detection of carotid intima and media thicknesses based on ultrasound B-mode images clustered with Gaussian mixture model.
Guiling QI ; Bingbing HE ; Yufeng ZHANG ; Zhiyao LI ; Hong MO ; Jie CHENG
Journal of Biomedical Engineering 2020;37(6):1080-1088
In clinic, intima and media thickness are the main indicators for evaluating the development of atherosclerosis. At present, these indicators are measured by professional doctors manually marking the boundaries of the inner and media on B-mode images, which is complicated, time-consuming and affected by many artificial factors. A grayscale threshold method based on Gaussian Mixture Model (GMM) clustering is therefore proposed to detect the intima and media thickness in carotid arteries from B-mode images in this paper. Firstly, the B-mode images are clustered based on the GMM, and the boundary between the intima and media of the vessel wall is then detected by the gray threshold method, and finally the thickness of the two is measured. Compared with the measurement technique using the gray threshold method directly, the clustering of B-mode images of carotid artery solves the problem of gray boundary blurring of inner and middle membrane, thereby improving the stability and detection accuracy of the gray threshold method. In the clinical trials of 120 healthy carotid arteries, means of 4 manual measurements obtained by two experts are used as reference values. Experimental results show that the normalized root mean square errors (NRMSEs) of the estimated intima and media thickness after GMM clustering were 0.104 7 ± 0.076 2 and 0.097 4 ± 0.068 3, respectively. Compared with the results of the direct gray threshold estimation, means of NRMSEs are reduced by 19.6% and 22.4%, respectively, which indicates that the proposed method has higher measurement accuracy. The standard deviations are reduced by 17.0% and 21.7%, respectively, which indicates that the proposed method has better stability. In summary, this method is helpful for early diagnosis and monitoring of vascular diseases, such as atherosclerosis.
Carotid Arteries/diagnostic imaging*
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Carotid Intima-Media Thickness
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Normal Distribution
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Ultrasonography