1.Automatic Registration between Portal Images and Reference Images in Radiotherapy
Chinese Journal of Medical Physics 2009;26(6):1481-1484
Objective: To correct the set-up error of patients during radiotherapy is very important for increasing treatment effective. Methods: This paper proposes a registration method based on portal images and reference images. Canny Operator was used to extract edge features. The extracted edge features were set as datum mark to calculate the maximal mutual information between the portal images and reference images. Parameters were optimized with simplex-simulated annealing optimization strategy. Results: The portal images and reference images of 29 patients with the cervix cancer and prostatic carcinoma were registrated in this paper. The results showed that the registration was precise, and the registration speed was increased remarkably. Conclusion: So this registration method can be applied for online estimation for set-up errors in clinical radiation.
2.Development of medical image registration
International Journal of Biomedical Engineering 2006;0(02):-
Medical image registration plays an important role in the research of medical image processing field. It is widely used in the areas of clinical diagnoses, treatment, quality assurance and evaluation of curative effect. This paper gives an overview on three medical image registration methods Correlation method, mutual information method, and wavelet transform method. Features of these method and their applications are reviewed.
3.The strategies on reducing ventilator-associated pneumonia incidence in ICU
Peng ZHENG ; Jianwei ZHOU ; Yaqin SONG
Chinese Journal of Primary Medicine and Pharmacy 2016;23(3):417-419
Objective To understand the incidence trend of ventilator -associated pneumonia(VAP)in ICU and to evaluate the effects of the interventions on the incidence of VAP,so as to provide scientific evidences for the prevention of VAP.Methods A study of 149 patients with VAP occurred in the 3 710 patients of ICU before and after intervention during 7 /2010 -12 /2014 in Wujin People's Hospital,Changzhou city was conducted.It was divided into two stages:baseline survey and stem expectations,VAP interventions included:training and education,chlorhexidine oral care and maintain appropriate endotracheal tube cuff pressure,elevated head of bed to up to 30°and improved hand hygiene.Hospital infection control professionals collected the number of patients,basic information,length of hospital stay,days of receiving mechanical ventilation and the VAP incidence data in ICU.And then change of the VAP incidence of the intervention before and after the intervention was compared and evaluation of the effect of combined intervention measures.Results Prospective data from 3 710 patients hospitalized in ICU were collected for an aggregate of 14 831 days,the utilization rate of ventilator was 55.2%.The occurrence of VAP was 149 cases.The average rate of VAP was 18.2 cases per 1 000 ventilator -day.VAP was associated with a crude mortality of 7.56%and with increased ICU LOS of 13.2d.As the results of the interventions,the rate of VAP was decreased from 52.38 /1 000 during 7 /2010 -6 /2011 to 5.71 /1 000 during 1 /2014 -12 /2014.Conclusion The rate of VAP in the inves-tigated ICU has led to a decreased incidence of VAP under the comprehensive interventions.
4.The study of wave intensity to evaluate early changes of cardiovascular function in patients with type 2 diabetes mellitus
Yaqin ZHOU ; Zheng HE ; Zhiling GAO
Journal of Chinese Physician 2015;17(4):551-553
Objective To explore the clinical value of wave intensity (WI) in evaluating early changes of cardiovascular function in patients with type 2 diabetes mellitus (T2DM).Methods Thirty T2DM patients without atherosclerosis by conventional ultrasonography were enrolled as case group,while thirty healthy volunteers were enrolled as control group.Two groups were well-matched in age and sex.Both of the case and control groups were taken WI test of carotid artery.The parameters of WI examinations in two groups were measured and compared.Results Compared to the control group,values of arterial stiffness index (β),elasticity modulus (Ep),pulse wave transit velocity (PWVβ),and decelerating wave intensity (W2) were significantly higher in T2DM group (P <0.05).Arterial compliance (AC) value was significantly reduced in T2DM group (P <0.05).Accelerating wave intensity (W1) value was higher in T2DM group without significant statistical differences (P > 0.05).Conclusions WI technique which can early assess the changes of left ventricular function and vascular elasticity in T2DM patients has important clinical value.
5.Evaluation the Results of C-reaction Protein Tested by Specific Protein Gold Measuring Instrument
Meijuan SHAO ; Li NI ; Yaqin ZHENG
Journal of Medical Research 2006;0(12):-
0.05).Conclusions Special protein gold measuring instrument had high sensitivity,good accuration and speediness,which was suitable for clinical LAB to test CRP.
6.Accuracy comparison of enhanced dynamic wedge modles among Pinnacle3 9.0 ACA and Eclipse7.3 AAA, PBC algorithm
Xiaofen XING ; Tong CUI ; Xuliang ZHENG ; Xuegang CHU ; Yaqin ZHENG
Chinese Journal of Radiation Oncology 2012;21(5):468-470
ObjectiveTo compare the accuracy of enhanced dynamic wedge (EDW) models of adaptive convolution algorithm (ACA) in Pinnacle3 9.0 and anisotropic analytical algorithm (AAA),and pencil beam convolution (PBC) algorithms in Eclipse7.3 treatment planning systems (TPS).MethodsTo evaluate the accuracy of the three algorithm models,we compared actual measurement values with TPS calculation values of EDW wedge factors under for different fields in which Varian-21EX 6 MV X-ray was applied,and also compared the actual dose distribution profile with that of TPS.ResultsThe deviations of EDW wedge factors of symmetry fields and asymmetric fields are within 2.8% and 19.4% for ACA in Pinnacle3 9.0.Meanwhile,the deviations are 1.0% and 2.0% for AAA,1.2% and 3.0% for PBC in Eclipse7.3.The deviations between measurement and calculation of all fields profile for ACA is within 3% and within 2.7% for AAA within 4.0% for PBC in wedge direction.For the dose distributions,we evaluated the pass rates of three algorithms using gamma analysis.The gamma pass rates among all the three algorithms in symmetry and asymmetric fields are above 87% and 85% respectively.After the removal of the penumbra zone,the pass rates among all the three algorithms are above 96% in symmetry fields,and above 95% in asymmetric fields,respectively.Conclusions AAA and PBC algorithms in symmetric and asymmetric fields can meet the need of clinical applications.While,wedge factor of ACA should not be used in clinical due to its greater error in asymmetric fields.
7.Dosimetric study in intensity-modulated radiotherapy with dissimilar position for cervical cancer
Xiaofen XING ; Yaqin ZHENG ; Zhifang ZANG ; Hegao WANG ; Hongxing JIN
Cancer Research and Clinic 2010;22(2):115-117
Objective To analyze the difference of irradiation dose and volume of organs at risk (OAR) particularly in small intestine between supine position and prone position on intensity-roodulated radiotherapy(IMRT) for cervical cancer. Methods 11 patients with Ⅱ_B-Ⅲ_B cervical cancer were scanned with supine position and prone position by CT.The CT images were transported to TPS,then target volumes were delineated and the IMRT plans were designed respectively.The prescribed dose was 95%PTV receiving 45 Gy in 23 fractions of 2 Gy.The exposure volumes of the OAR at different position and different dose levels in the dose volume histograms (DVH) were compared and analyzed.Results When tlle dose di8tributions met to the clinic request,the exposure volumes of small intestine at prone position were redueed than that at supine position in dose range 46-30 Gy(P<0.05),but this phenomenon Was not distinct in low dose range(< 20 Gy)(P>0.05).The exposure volumes of bladder, rectum, femur head and spine cord were no obviously differences at dissimilar position. Conclusion IMRT of cervical cancer should adopt prone position.because their small intestine will be protected better.
8.Anxiety and depression of patients with amyotrophic lateral sclerosis
Minying ZHENG ; Yaqin LI ; Xun ZENG ; Yongqing HUANG
Modern Clinical Nursing 2014;(9):4-7
Objective To study the anxiety and depression in patients with amyotrophic lateral sclerosis(ALS).Method One hundred and seventy-four ALS patients were evaluated by self-rating anxiety scale(SAS)and self-rating depression scale(SDS) to study the anxiety and depression in them.Results In 174 ALS patients,21 had anxiety(12.07%)and 65 the depression(37.36%). The scores of SAS and SDS in the ALS patients were significantly higher than the national norm(P<0.05).The depression incidence in the female patients was significantly higher than the male(P<0.05).Conclusions Anxiety and depression are more severe than those in ALS patients than those in normal people.Psychological support is important for these patients,especially for those female patients.
9.Influence of dose rate reference control level on the design of accelerator shielding
Yaqin ZHENG ; Yajun KANG ; Xuegang CHU ; Fang GUO
Chinese Journal of Radiological Medicine and Protection 2015;35(2):139-141
Objective To explore the influence of dose rate reference control level on the design of accelerator shielding.Methods According to the standards of GBZ 126-2011,GBZ/T 201.1-2007 and GBZ/T 201.2-2011,two different shielding calculation methods,based on the dose rate reference control level and week dose control level,were used to calculate and compare the thickness of accelerator room shielding.Results Under the same condition of maximum weekly workload,the obtained results were different when the calculated dose rate reference control value was larger than dose rate reference control level (2.5 μSv/h).The maximum difference of shielding thickness reached 64 cm.Meanwhile,considering dose rate reference control level,the different accelerator rates could lead to different radiation shielding thickness.Conclusions The dose rate at reference point must be first calculated before calculating shielding thickness.The calculation should be made on the premise that dose rate reference control level is met.
10.Comparison of dose distribution between three dimensional conformal radiotherapy and intensity-modulated radiotherapy for pelvis metastasis of post-hysterectomy cervical carcinoma
Junli REN ; Li FAN ; Yaqin ZHENG ; Lili LI
Cancer Research and Clinic 2010;22(z1):14-16
Objective To compare the differences of target-volume(PTV) coverage and organ at risk (OAR) protection between three dimensional conformal radiotherapy (3DCRT) and intensity-modulated radiotherapy(IMRT) for patients with pelvis metastasis of cervical cancer underwent radical hysterectomy and pelvic lymphadenectomy. To explore the optimal treatment methods for pelvis metastasis of cervical cancer.Methods 10 patients with pelvis metastasis of cervical cancer underwent radical hysterectomy and pelvic lymphadenectomy were selected for this study. The images scanned by CT were transferred to treatment planning system to generate 3DCRT and IMRT plans. The impacts of 3DCRT on PTV were compared with those of IMRT. Isodose line and dose volume histograms(DVH) were used to evaluate to the dose-distribution in PTV and OAR. Results For 95 % confidence interval, the margin from CTV to PTV was 1 cm. Conformal indexs (CIs) of PTV for 3, 4, 5 and 6 fields 3DCRT were 0.46, 0.67, 0.68 and 0.68, respectively. When beyond 4 fields, the advantage of adding fields was not significant. CIs of PTV for 5, 7, 9, 11 and 13 fields IMRT were 0.75, 0.83 0.84, 0.85 and 0.85, respectively. When beyond 9 fields, the advantage of adding fields was not significant. The maximum dose of the bowl and spine cord in IMRT plans were lower than that in the 3DCRT plans (P <0.05). Maximum dose of OAR had no significant differences (includingt the bone, recttum and bladder) between IMRT and 3DCRT plans. Conclusion For patients with pelvis metastasis of cervical cancer after radical surgery, 4 fields planning in 3DCRT and 9 fields planning in IMRT are feasible. At high dose levels, the IMRT plans can more significantly protect the bowl and spine cord and decrease the radiation volume of colorectal and urinary bladder at risk than 3DCRT, so IMRT may potentially diminish probability of the normal tissue complications.