1.The application of a 2D diode array in verifying the composite dose distribution of intensity modulated radiation therapy
Qilin LI ; Xiaowu DENG ; Lixin CHEN ; Xiaoyan HUANG ; Shaomin HUANG
Chinese Journal of Radiological Medicine and Protection 2011;31(3):359-362
Objective In order to explore the ways of reflecting the dose distribution in the implementation of the of IMRT (intensity modulated radiation therapy),a 2D diode array (2D-DA) was used in verifying the composite dose distribution of IMRT plans in the way of multi-gantry-angle composite (MGAC).Methods IMRT quality assure (QA) plans of 27 patients,based on the 2D-DA and solid water phantom,were designed and verified in two ways of single-gantry-angle composite (SGAC) and MGAC verifications.The comparison and analyzation of the dose distributions of the TPS calculation and the measurement of the 2D-DA were done.Results (1) When the beam central axes were not superposed with the detectors'plane of the 2D-DA,the verification passrate of SGAC and MGAC planar dose distribution of 27 patients'IMRT plan were 94.56%±4.28% and 94.81%±3.80% (the criteria:rvalue,3 ram/3%),respectively.There was no statistical difference between the results of two sets (t =-0.213,P>0.05).(2) When one of the beam central axes was superposed with the detectors'plane of the 2D-DA,the verification passrate of MGAC planar dose distribution were 79.72%±12.77%.Conclusions Using the 2D-DA with a proper phantom,there was no statistical difference in the SGAC and MGAC verifications of IMRT plans when the beam central axes were not superposed with the detectors'plane.However,the MGAC dose distribution can provide more about the clinical dosimetry,and the errors in the implementation of the of IMRT were easier located.
2.Establishment and optimization of loop-mediated isothermal amplification for rapid detection of pseu-domonas aeruginosa
Qun LIN ; Jieyi FENG ; Jinhua HUANG ; Shaomin HUANG ; Zhigang WU
The Journal of Practical Medicine 2016;32(16):2677-2679
Objective To establish a Loop-mediated Isothermal Amplification (LAMP) for Pseudomonas aeruginosa rapid detection. Method 152 P. aeruginosa strains isolated from nasal swabs and 30 reference strains were applied. P. aeruginosa ATCC15442 was used to develop LAMP amplification and evaluate sensitivity and specificity. Results Sensitivity of LAMP was 103 times higher than PCR, with DNA amount as 132 fg. When LAMP was applied to 30 reference strains and 152 P. aeruginosa strains , the specification was 100% while iden-tification rate reached 94.7%. Conclusion The establishment LAMP showed a promising prospect in P. aerugi-nosa rapid detection.
3.Comparison of planning parameter selection for volumetric modulated arc therapy of nasopharyngeal carcinoma in two different treatment planning systems
Yan MA ; Jian ZHENG ; Xiaowu DENG ; Shaomin HUANG ; Li CHEN
Chinese Journal of Radiation Oncology 2015;(5):564-568
Objective To investigate the impact of planning parameter settings on plan quality and delivery efficiency of VMAT for nasopharyngeal carcinoma with two treatment planning systems (TPS),as references for clinic plan optimization. Methods 25 patients with nasopharyngeal carcinoma were selected and planned for SIB?VMAT treatment. The same planning aims were used in the two kinds of TPS ( TPS?1 and TPS?2). Multiple planning parameters were set for plan optimization. Dose distribution to the target volumes and organs at risk,monitor unit ( MU) and delivery time were compared. Paired t?test or one?way ANOVA was used for the data which was in accordance to normal distribution;otherwise, nonparametric Wilcoxon signed rank test or nonparametric Friedman test was used. Results More segments lead to better plan quality and less MU but longer delivery time ( Minor impact was observed when segment number was larger than 120) in TPS?1,while it had little impact on both plan quality and delivery efficiency in TPS?2. Comparing to single?arc plans,dual?arc VMAT achieved no significant benefit in plan quality but had more MU and longer delivery time in TPS?1 ( P= 0?000 ) . However, dual?arc VMAT plans had better dose distribution in TPS?2, decreased the maximum and mean dose for spinal cord in 3?9% and 13?7%respectively (P=0?000,0?000).Changing the settings of maximum or minimum dose rate did not affect the plan quality in both of the tested TPSs. Increasing the maximum or minimum dose rate reduced the delivery time but the latter increased the number of MU ( P=0?000,0?000) . Conclusions VMAT plan quality and delivery efficiency is affected significantly and differently by planning parameter settings for two TPSs. Trial test should be conducted for different TPS to determine the optimal parameter settings.
4.Shooting and assessing the portfilm in radiation therapy
Jie LU ; Zhaoliang WANG ; Shaomin HUANG ; Guangqiang LAI
Chinese Journal of Radiation Oncology 1995;0(02):-
Objective To discuss how to practise and consummate to shoot and assess the portfilm for radiotherapy. Methods Double radiography technique was used to take a portfilm. The reference mark points (plumbum points) were added into the field at the first exposure and the cross lines drawn based on the plumbum point images were definited as the reference coordinate to the actual field. Then, the portfilm was compared and analyzed with the simulator planning film. Results The images of both plumbum points and block boundaries were distinct in the portfilm, but the resolution and contrast of the tissue structure image was inferior to the ordinary film from simulator. However, all different structures and positions could be identified in order to assess if the actual field coincided with the radiation planning. Conclusions Although the real-time property of the portfilm is inferior to the electric portal image device (EPID), the double radiography portfilm is feasible as an important quality control method in radiation therapy due to its lower price and easier performance. The design of reference points is the key point in this technique.
5.Relationship between multiple risk factors and coronary artery lesions in the patients with coronary heart disease and metabolic syndrome
Shaomin ZHANG ; Zhiqi XIA ; Lei ZHU ; Xiaoling PENG ; Desheng HUANG
Journal of Third Military Medical University 2003;0(15):-
Objective To investigate the relationship between coronary artery lesions and multiple risk factors in the patients with metabolic syndrome (MS) and coronary heart disease (CHD). Methods Totally 429 patients were definitely diagnosed with CHD by coronary arteriography and their BMI, BP, FBG, TG, HDL-c as well as age, gender, smoking, TC, LDL-c, UA were recorded. All patients were divided into two groups: CHD with MS, CHD. Results BMI, BP, FBG, TG, HDL-c, TC, LDL-c and UA were significantly higher in CHD with MS group than those in CHD group (P
6.Role of nursing classification and marking management in ICU nursing management
Xiaoling XIONG ; Yanling HUANG ; Shaomin HE ; Qingfang DAI
Modern Clinical Nursing 2014;(4):59-61
Objective To probe into the role of nursing classification and marking management in ICU nursing management. Methods According to the admission date,the first 87 patients hospitalized in our department were assigned into the control group and another 84 into the intervention group.Then the human resources were divided based on the ABCD nursing classification and marking management for ICU.The two groups were compared in terms of adverse events.Results The incidences of pressure sores, non-planned extubation,improper clinostatism for using respirator,hypoglucycaemia during reinforced treatment with insulin, respirator-associated pulmonary pneumonia,tube-associated infection,and multidrug resistant bacteria in the intervention group were all significantly lower than those in the control group (allP<0.05).Conclusion The nursing classification and marking management for ICU nursing management can enhance the nursing quality.
7.Influence of T- and B-cell-deficiency on retinal neurocytes of mice withacute ocular hypertension
Yanjiao, HUO ; Ping, HUANG ; Shaomin, ZHANG ; Chun, ZHANG
Chinese Ophthalmic Research 2010;28(3):193-197
Background Recently,the study on the cause of optic nerve damage induced by glaucoma is of concern in ophthalmology.Some research showed that the immune system is associated with glaucoma-induced optic neuropathy.Acute ischemia-reperfusion is an ideal model of studying optic neuropathy.ObjectiveThe present study investigates the effect of T and B lymphocyte deficiency on the retinal neurocytes of mice with acute intraocular hypertension.Methods Sixteen SPF CB-17/Icr.Cg-Prkdc~(scid)Lyst~(bg)/CrlVR mice 6-8 week-old (severe combined immunodeficiency mouse,SCID) were used in this study and 16 age-matched SPF wild type (C57BL/6) mice served as controls.The ischemia-reperfusion injury models were induced in the right eyes of 10 SCID mice and 10 C57BL/6 mice through intra-anterior chamber infusion of balanced saline solution for 45minutes to increase the intraocular pressure to 104mmHg,and the left eyes served as model controls.The other 6 SCID mice and 6 C57BL/6 mice served as normal control group.10g/L (2μL) of FlouroGold was injected into the brains of the mice for the labeling of surviving retinal ganglion cells 21 days after ischemia-reperfusion.The thickness of retinal inner nuclear layer was measured by H&E staining under the fluorescent microscope 21 days after ischemic insult.The use of the animals followed the Standard of Association for Research in Vision and Ophthalmology.Results In normal control mice,the morphology of retinal ganglion cells (RGCs) and retinal structure were similar between SCID mice and C57BL/6 mice.The differences in the numbers of RGCs and retinal thickness were insignificant between the two types of mice(P>0.05).In the experimental mice,the surviving RGCs were strikingly increased in SCID mice (91%±5%) compared with C57BL/6 mice(78%±5%)(P=0.003).The thickness of the retinal inner nuclear layer was obviously thinner in the model eyes (22.44±1.70μm) compared to model control eyes (31.06±3.75μm) in C57BL/6 mice(P=0.004),but no statistically significant difference was found between the model eyes and model control eyes in SCID mice (33.52±2.13μm vs 34.06±3.00μm) 21 days after ischemia-reperfusion injury(P>0.05).Conclusion T and B lymphocytes deficient mice show a better tolerance to acute intraocular hypertension than the wild type C57BL/6 mice.
8.Comparison and evaluation of VMAT and IMRT for the treatment of initial treated nasopharyngeal carcinoma
Dandan ZHANG ; Shaomin HUANG ; Xiaowu DENG ; Guangshun ZHANG ; Xiaoyan HUANG ; Wenzhao SUN ; Hailei LING
Chinese Journal of Radiation Oncology 2012;21(4):364-368
ObjectiveTo compare planning quality,treatment efficiency and delivery accuracy for initial treated nasopharyngeal carcinoma (NPC) with step & shoot intensity modulated radiation therapy (ssIMRT) and volumetric modulated arc therapy (VMAT).These results will help make a clinic choice of the therapeutical technique.MethodsTwenty-six NPC cases were planned with the same dose prescription and objective constrains by means of 9-field ss-IMRT and VMAT respectively.Compare:( 1 ) plan dosimetric distribution,conformity index and homogeneity index of the targets,the average dose,maximum dose and interested dose-volume histograms of organs at risk (OAR) et al;(2) delivery times of the therapy plans ;(3) the accuracy of treatment plans dose verification.ResultsBoth therapeutical plans can achieve the clinic dosimetric demands.Compared to ss-IMRT,VMAT had less inferior target coverage.The CI and HI of the PGTV was 0.57 and 0.08 ( ss-IMRT),0.48 and 0.12 (VMAT) respectively ( t =-4.52,- 8.33,P =0.000,0.000).Except of brain stem,VMAT had higher mean dose and maximum dose of OARs than ss-IMRT (t=-9.57 - -3.71,P=0.000 -0.001).The spinal cord D1cc and parotids D50% were increased by 11.9% and 6.5% averagely.The treatment times of ss-IMRT and VMAT were 803.7 s and 389.3 s respectively (t =24.12,P =0.000),while V MAT decreasing by 51.6%.The pass ratios of γ (3mm,3% ) from the dose verification were 99.4% (ss-IMRT) and 98.0% (VMAT) respectively ( t =5.19,P =0.000).ConclusionsThe dose distribution of VMAT for initial treated nasopharyngeal carcinoma can achieve the clinic demands,but slightly worse than 9-field ss-IMRT.VMAT has the advantage of high efficiency and dosimetric accuracy.
9.Clinical characteristics with radiation encephalopathy after intensity-modulated radiotherapy in nasopharyngeal carcinoma patients: analysis of 42 cases
Shengfa SU ; Ying HUANG ; Fei HAN ; Chuanmiao XIE ; Shaomin HUANG ; Taixiang LU
Chinese Journal of Radiological Medicine and Protection 2012;32(1):60-64
Objective To explore the incidence, clinical characteristics, and prognosis of radiation encephalopathy (REP) in nasopharyngeal carcinoma (NPC) patients after intensity-modulated radiotherapy (IMRT). Methods 870 NPC patients confirmed pathologically and without distant metastasis received radical IMRT,570 of which received chemotherapy simultaneously,and followed up for 6 -104 months (with a median of 40 months),undergoing magnetic resonance imaging (MRI) once every 3 months within the first 3 years after treatment and then once every year.The clinical manifestations were observed.In 29 of these 42 patients diagnosed as with REP,the dose distributions of REP lesions were evaluated.Results 4.83% of the NPC patients (42/870) were diagnosed as with REP.There were 39 cases with pure temporal lesion (bilateral in 6 cases),with a median latency period of 30 months (6 -56 months),2 cases with pure cerebral stem lesion both with a latency period of 14 months,and one case with lesions in temporal lobe and cerebral stem with the latency period of 18 months.REP was not observed in the stage T1-2 patients.The incidence rate of REP was 3.09% for the stage T3 patients and 14.35% for the stage T4 patients.Twenty-two patients underwent following-up MRI after initial diagnosis of REP.After medication or surgical treatment the conditions became better or stable in the most cases. Dosimetric analysis of 32 injured temporal lobes in 29 patients found that the maximal dose was in the contrastenhanced lesions in 27 injured temporal lobes and in edema regions in 5 injured temporal lobes.For each patient,the maximal dose in the normal temporal lobe was lower than that in the injured temporal lobe.In the same patient,the maximal dose,minimal dose,and mean dose of contrast-enhanced lesions were all higher than those in the edema region.Conclusions The incidence of REP after IMRT is high,especially in local advanced NPC patients. Active treatment stabilizes or improves the REP condition. REP is positively correlated with dose of irradiation to brain tissue.
10.Four-dimensional CT in the study of lung volume and respiratory movement
Zongwen SUN ; Xiaoyan HUANG ; Yong BAO ; Li ZHANG ; Shaomin HUANG ; Wei FAN ; Ming CHEN ; Xiaowu DENG
Chinese Journal of Radiation Oncology 2008;17(6):437-440
Objective To evaluate the respiratory movement of the both lungs with four-dimensional CT(4DCT), and determine the optimal respiratory phase series CT images for radiation dose calculation. Methods From November 2005 to November 2006,thirty patients with lung cancer who received 4DCT scan were enrolled,including 15 left and 15 right lung cancer cases,25 men and 5 women. The media age was 55 (35-78) years old. After 4DCT scanning, the image was treated with Advantage 4D workstation,and then transmitted into Pinnacle station( Adac 7.4). The both lungs were automatically outlined using Pinnacle station with CT recognition value of-900 to-200 Hu. Then-the same physician examined the unreasonable parts and revised them. After the delineation was completed,the volume of 10 respiratory phases of lung was obtained. Results The average respiratory phase in inspiratory and expiratory phases was 78.87%±2.71% and 26.32%±3.17% in the tumor located lung,77.55%±2.81% and 24.73%±2.55% in the healthy lung. The maximum and minimum mean volume was 106.48%±3.00% and 94.23%±2.78% in the tumor located lung,107.47%±2.43% and 93.65%±2.32% in the healthy lung. The volume at the end of inspiratory and expiratory was 106.43%±3.07% and 94.63%±2.71% in the tumor located lung, 107.37%±4.62% and 93.98%±2.34% in the healthy lung. Conclusions The series CT images scan on 20% ,30% and 80% respiratory phases are reasonable for radiation dose calculation. The maximum and minimum average lung volumes are almost equal to those at the end of inspiratory and expiratory.