1.Invasiveness assessment by CT quantitative and qualitative features of lung cancers manifesting ground-glass nodules in 555 patients: A retrospective cohort study
Yantao YANG ; Wei WANG ; Yichen YANG ; Biying WANG ; Huilian HU ; Ziqi JIANG ; Dezhong CAI ; Yaowu DUAN ; Jiezhi JIANG ; Jia LUO ; Guangqiang ZHAO ; Yunchao HUANG ; Lianhua YE
Chinese Journal of Clinical Thoracic and Cardiovascular Surgery 2024;31(01):51-58
Objective To explore the correlation between the quantitative and qualitative features of CT images and the invasiveness of pulmonary ground-glass nodules, providing reference value for preoperative planning of patients with ground-glass nodules. Methods The patients with ground-glass nodules who underwent surgical treatment and were diagnosed with pulmonary adenocarcinoma from September 2020 to July 2022 at the Third Affiliated Hospital of Kunming Medical University were collected. Based on the pathological diagnosis results, they were divided into two groups: a non-invasive adenocarcinoma group with in situ and minimally invasive adenocarcinoma, and an invasive adenocarcinoma group. Imaging features were collected, and a univariate logistic regression analysis was conducted on the clinical and imaging data of the patients. Variables with statistical difference were selected for multivariate logistic regression analysis to establish a predictive model of invasive adenocarcinoma based on independent risk factors. Finally, the sensitivity and specificity were calculated based on the Youden index. Results A total of 555 patients were collected. The were 310 patients in the non-invasive adenocarcinoma group, including 235 females and 75 males, with a meadian age of 49 (43, 58) years, and 245 patients in the invasive adenocarcinoma group, including 163 females and 82 males, with a meadian age of 53 (46, 61) years. The binary logistic regression analysis showed that the maximum diameter (OR=4.707, 95%CI 2.060 to 10.758), consolidation/tumor ratio (CTR, OR=1.027, 95%CI 1.011 to 1.043), maximum CT value (OR=1.025, 95%CI 1.004 to 1.047), mean CT value (OR=1.035, 95%CI 1.008 to 1.063), spiculation sign (OR=2.055, 95%CI 1.148 to 3.679), and vascular convergence sign (OR=2.508, 95%CI 1.345 to 4.676) were independent risk factors for the occurrence of invasive adenocarcinoma (P<0.05). Based on the independent predictive factors, a predictive model of invasive adenocarcinoma was constructed. The formula for the model prediction was: Logit(P)=–1.293+1.549×maximum diameter of lesion+0.026×CTR+0.025×maximum CT value+0.034×mean CT value+0.72×spiculation sign+0.919×vascular convergence sign. The area under the receiver operating characteristic curve of the model was 0.910 (95%CI 0.885 to 0.934), indicating that the model had good discrimination ability. The calibration curve showed that the predictive model had good calibration, and the decision analysis curve showed that the model had good clinical utility. Conclusion The predictive model combining quantitative and qualitative features of CT has a good predictive ability for the invasiveness of ground-glass nodules. Its predictive performance is higher than any single indicator.
2.Analysis of blood testing indicators in HIV patients co-infected with different genotypes of HCV in Kunming area of Yunnan Province
LIU Junyi ; KANG Lijuan ; WANG Shimin ; ZHU Yantao ; ZHANG Mi ; ZHANG Nian ; XIE Qi ; LIU Shifang ; YANG Jiantao ; LI Xiao ; HE Quanying ; WANG Jiali
China Tropical Medicine 2024;24(3):252-
Objective To understand the genotyping of human immunodeficiency virus (HIV) co-infected hepatitis C virus (HCV) patients in Yunnan Province, and to analyze the differences in viral load, biochemical indicators, and blood routine indicators among different genotypes, in order to provide a laboratory basis for the diagnosis and clinical treatment of HIV/HCV co-infected patients. Methods From November 2022 to June 2023, the serum samples and basic information of patients diagnosed with HIV/HCV co-infection were collected in the antiviral outpatient clinic of Yunnan Provincial Hospital of Infectious Diseases. The HCV viral load was detected by one-step qRT-PCR amplification, the positive samples were sequenced, and genotyping was determined based on NS5 gene sequence. The differences in biochemical and blood routine indexes between HIV patients co-infected with different HCV genotypes and low/high viral loads were analyzed. Results A total of 126 HIV/HCV co-infected patients were collected, including 20 HCV genotype 1 (15.9%), 91 HCV genotype 3 (72.2%), and 15 HCV genotype 6 (11.9%). The maximum and minimum viral load of the three HCV genotypes were as follows: HCV type 1 (1.0×108, 4.8×104 IU/mL), HCV type 3 (2.2×108, 2.9×102 IU/mL), and HCV type 6 (8.1×107, 6.8×104 IU/mL). The results showed that there was no significant difference between HIV co-infection with different genotypes of HCV and three HIV treatment schemes, including nucleoside reverse transcriptase inhibitors+integrase strand transfer inhibitors (NRTIs+INSTIs), nucleoside reverse transcriptase inhibitors+non-nucleoside reverse transcriptase inhibitors (NRTIs+NNRTIs) and nucleoside reverse transcriptase inhibitors+protease inhibitor (NRTIs+PLs), and the viral load of patients (P>0.05). The analysis of biochemical indexes such as total bilirubin (TBIL), direct bilirubin (DBIL), alanine aminotransferase (ALT), aspartate aminotransferase (AST), creatinine (CREA), and blood routine indexes such as white blood cell (WBC), red blood cell (RBC), hemoglobin (HGB), platelet (PLT), mean corpuscular hemoglobin (MCH) and mean corpuscular hemoglobin concentration (MCHC) among different HCV genotypes and low/high viral loads showed that there was no significant difference in biochemical indexes and blood routine indexes between low/high viral loads of HIV co-infected HCV patients (P>0.05); however, the biochemical indicators TBIL, IBIL and MCHC were significantly different statistically between patients with genotype 3 HCV infection and those with genotype 1 HCV infection (P<0.05), while other biochemical and blood routine indexes were not statistically different among different HCV genotypes (P>0.05). Conclusions There are six subtypes of HCV co-infection in HIV patients in Kunming, Yunnan Province, including three genes of genotype 1, 3, and 6. Among them, genotype 3 HCV is the main prevalent genetic virus among HIV co-infected populations. The TBIL, IBIL and MCHC values of HIV patients co-infected with HCV type 3 are different from those infected with HCV type 1.
3.Molecular characteristics of Japanese encephalitis virus carried by Culex tritaeniorhynchus in Dongchuan District, Kunming City, Yunnan Province
Yangyang GU ; Yuwen HE ; Yiju CHEN ; Zhenxing YANG ; Nan LI ; Shunyan LÜ ; Yantao ZHU ; Fangchao RUAN ; Jiali WANG ; Jinglin WANG
Chinese Journal of Schistosomiasis Control 2024;36(4):361-369
Objective To isolate the Japanese encephalitis virus carried by Culex tritaeniorhynchus in Dongchuan District of Yunnan Province and analyze its molecular characteristics, so as to provide insights into the prevention and control of Japanese encephalitis in Yunnan Province. Methods Mosquito specimens were collected using mosquito-trapping lamps from pig farms in Batang Village and Xiaoxin Village, Dongchuan District, Kunming City, Yunnan Province in July 2016, and the mosquito species was identified according to the mosquito morphology. Then, 60 to 100 mosquitoes of each species served as a group and were ground. Baby hamster kidney-21 (BHK-21) cells and Aedes albopictus clone C6/36 cells were used for virus isolation, and positive isolates were identified using flavivirus primers. The positive isolates were amplified using reverse transcription polymerase chain reaction (RT-PCR) assay with 15 pairs of specific primers covering the full length of the genotype I Japanese encephalitis virus, and DNA sequence assembly was performed using the software SeqMan in the DNASTAR package. The obtained sequences were aligned with the complete sequences of 38 Japanese encephalitis virus downloaded from the GenBank with the software MegAlign, and the nucleotide and amino acid homology analyses of the obtained sequences were performed. The difference in amino acid sites was analyzed with the software GeneDoc, and phylogenetic trees were created based on the sequences of the coding region and E protein of the isolated Japanese encephalitis virus with the software Mega X. In addition, the secondary and tertiary structures of the E protein of the Japanese encephalitis virus were predicted using the online tool SOPMA and the software Swiss-Model. Results A total of 5 820 mosquitoes were collected and 3 843 Cx. tritaeniorhynchus (66.03%) were identified according to the mosquito morphology. A positive virus isolate, termed YNDC55-33, was isolated from Cx. tritaeniorhynchoides following batches of virus isolation from mosquito specimens, and cytopathic effect was observed following inoculation into BHK-21 and C6/36 cells. The YNDC55-33 virus isolate was successfully amplified with the flavivirus primes, and a long sequence containing 300 nucleotides was obtained. Following sequence alignment using the BLAST tool, the sequence of the YNDC55-33 virus isolate had high homology with that of the genotype I Japanese encephalitis virus. A long sequence with 10 845 nucleotides in length, which encoded 3 432 amino acids, was obtained by splicing the full sequence of the YNDC55-33 virus isolate. Phylogenetic analysis based on the whole-genome sequence and E gene sequence of the YNDC55-33 virus isolate showed that the new YNDC55-33 virus isolate was most closely related to the genotype I Guizhou isolate (GenBank accession number: HM366552), with nucleotide homology of 98.5% and amino acid homology of 99.4%, and the YNDC55-33 virus isolate shared 97.96% ± 0.33% nucleotide homology and 99.35% ± 0.08% amino acid homology with other genotype I Japanese encephalitis virus isolates, and < 90% nucleotide homology and < 98% amino acid homology with other genotypes of Japanese encephalitis virus. The YNDC55-33 virus isolate and the live attenuated virus vaccine candidate SA14-14-2 isolate differed at 16 amino acid sites on E gene, and 7 out of 8 key amino acid sites related to neurovirulence. The secondary and tertiary structures of the E protein of the YNDC55-33 virus isolate were predicted to be characterized by random coils. Conclusions A genotype I Japanese encephalitis virus was isolated from Cx. tritaeniorhynchus in Dongchuan District, Kunming City. This virus isolate and the live attenuated virus vaccine candidate SA14-14-2 isolate does not differ at antigenic epitopes-related key amino acid sites, and the major protein structure of the virus isolate is random coils. This study adds new data for the epidemiological distribution of Japanese encephalitis virus in Yunnan Province, which may provide insights into the prevention and control of Japanese encephalitis in the province.
4.The cutoff value of small airway dysfunction in children with bronchial asthma
Wei CHEN ; Zhe YANG ; Chuanhe LIU ; Xinyu JIA ; Yantao ZHANG ; Xin SONG ; Shuo LI
Chinese Journal of Pediatrics 2024;62(3):245-249
Objective:To explore the cutoff value for assessing small airway dysfunction in children with asthma.Methods:A total of 364 asthmatic children aged 5 to 14 years, with normal ventilatory function, followed up at the Asthma Clinic of the Children′s Hospital of Capital Institute of Pediatrics from January 2017 to January 2018, were selected as the case group. Concurrently, 403 healthy children of the same age range and without any symptoms in the community were chosen as the control group, and pulmonary function tests were conducted. The values of forced expiratory volume in 1 second (FEV 1), forced vital capacity (FVC), forced expiratory flow at 50% of FVC (FEF 50), forced expiratory flow at 75% of FVC (FEF 75) and maximum mid-expiratory flow (MMEF) were compared between case group and control group. Statistical tests such as t-test, χ2 test, or Mann-Whitney U test were used to analyze the differences between the groups. Receiver operating characteristic (ROC) curves were constructed, and the maximum Youden Index was utilized to determine the optimal cutoff values and thresholds for identifying small airway dysfunction in asthmatic children. Results:This study comprised 364 children in the case group (220 boys and 144 girls) and 403 children in the control group (198 boys and 205 girls). The small airway parameters (FEF 50%pred, FEF 75%pred, MMEF%pred) in the asthmatic group were significantly lower than in the control group (77% (69%, 91%) vs. 95% (83%, 109%), 67% (54%, 82%) vs. 84% (70%, 102%), 76% (66%, 90%) vs. 97% (86%, 113%), Z=12.03, 11.35, 13.66, all P<0.001). The ROC curve area under the curve for FEF 50%pred, FEF 75%pred, MMEF%pred was 0.75, 0.74, and 0.79, respectively. Using a cutoff value of 80% for FEF 50%pred achieved a sensitivity of 56.9% and specificity of 81.4%. A cutoff value of 74% for FEF 75%pred resulted in a sensitivity of 67.3% and specificity of 69.2%. Finally, using a cutoff value of 84% for MMEF%pred achieved a sensitivity of 67.9% and specificity of 77.2%. Conclusion:In the presence of normal ventilatory function, utilizing FEF 50<80% predicted or MMEF<84% predicted can accurately serve as criteria for identifying small airway dysfunction in children with controlled asthma.
5.Effect of the setting of control point of Monaco radiotherapy planning system on dosimetry of dIMRT plan for esophageal cancer of middle and lower segment
Hao WANG ; Yunyi YANG ; Yi LI ; Qi DING ; Feng GUO ; Yantao GONG ; Genxiang CHEN ; Ya CHE ; Yinghong REN
China Medical Equipment 2024;21(9):1-6
Objective:To study the dosimetry effects of differently selected values of control point(CP)in Monaco radiotherapy planning system on dynamic intensity modulated radiation therapy(dIMRT)for esophageal cancer of middle and lower segment.Methods:Thirteen patients with esophageal cancer at middle and lower segment who received dIMRT in Shangluo Central Hospital from January to June 2023 were selected.In the Monaco radiotherapy planning system,nine groups of dIMRT plans were designed for each patient according to the 9 kinds of CP limit values(10,20,30,40,50,60,70,80 and 90).There were not changes in other optimized parameters except CP parameter.The differences of the dosimetry between target region and organs at risk(OAR)included lung,heart and spinal cord were analyzed.Results:With the increase of the CP limit value,the maximum dose of the target region which was radiation dose(D2%)of 2%volume of target region,the mean dose,which was radiation dose(D50%)of 50%volume of target region,and the homogeneity index(HI)appeared a trend of gradual stability after reduction,and the radiation dose(D98%)of 98%volume of target region which was the minimum dose of target region and the conformance index(CI)appeared a trend of gradual stability after increase.There was not significant in each dose indicator of OAR(P>0.05).The variation ranges of lung at 5,10,20,30 Gy dose(V5,V10,V20 and V30)were respectively 1.13%,0.75%,0.29%and 0.19%,and the maximum deviation of mean dose(Vmean)of lung was 18.7 cGy.The variation ranges of V10,V20,V30 and V40 in the heart were respectively 2.2%,1.23%,1.39%and 1.12%,and the maximum deviation of Vmean in the heart was 63.85 cGy,and the maximum deviation of Dmax in the spinal-cord was 70.78 cGy.There were statistically significant differences in the actual CP number(CPs),execution time(DT)of plan,and ratio value of machine unit(MU)of the complexity of plan to CPs(MU/CPs)among the plans of 9 groups(F=2.857,25.145,135.467,P<0.05),respectively.Conclusion:In the dIMRT plan of esophageal cancer of middle and lower segment,the maximum CP value is set at between 40-50,which can reduce the optimization time of the plan,the number of subfields and the treatment time of patients under the premise of meeting the dose of the target region and the OAR.
6.Effect of hyperoside on transverse aortic constriction-induced cardiac hypertrophy
Xiaodong ZHANG ; Yantao ZHANG ; Lei ZHANG ; Wenting DONG ; Huixian AN ; Yang HAN ; Jie ZHANG ; Zhiguo LIU ; Wei LI ; Wei WANG
Acta Universitatis Medicinalis Anhui 2023;58(12):2058-2063
Objective To investigate the protective effect of hyperoside(Hyp)on transverse aortic constriction-in-duced cardiac hypertrophy and its possible mechanism.Methods Forty 8-week-old male C57BL/6J mice were randomly divided into four groups:Sham group,TAC group,Hyp+TAC group and Hyp+ML385+TAC group.Four weeks after operation,cardiac function including left ventricular ejection fraction(LVEF),left ventricular fractional shortening(LVFS)and left ventricular end-diastolic posterior wall thickness(LVPWd)were measured with echocardiography.HE staining was used to evaluate the myocyte cross-sectional area.Masson staining was used to determine myocardial fibrosis.The ratio of heart weight/body weight was calculated.DHE staining was used to assess reactive oxygen species(ROS)production.The mRNA levels of atrial natriuretic peptide(ANP),brain natriuretic peptide(BNP)and β-myosin heavy chain(β-MHC)were detected by qRT-PCR.The protein levels of NF-E2-related factor 2(Nrf2),heme oxygenase-1(HO-1),superoxide dismutase2(SOD2)and NAD-PH-Oxidase 2(gp91phox)were detected by Western blot.Differences among groups were compared by one-way a-nalysis of variance,and LSD-t test was used for comparison between the two groups.Results Compared with the Sham group,the values of LVEF and LVFS in the TAC group decreased(P<0.01).The value of LVPWd,the cross-sectional area,fibrosis and the ratio of HW/BW increased(P<0.01).The mRNA levels of ANP,BNP andβ-MHC were upregulated(P<0.01).The ROS production and gp91phox protein level were elevated in the TAC group(P<0.01),while the protein levels of Nrf2,HO-1 and SOD2 decreased(P<0.01).Compared with the TAC group,the values of LVEF and LVFS in the Hyp+TAC group increased(P<0.01).The value of LVPWd,the cross-sectional area,fibrosis and the ratio of HW/BW decreased(P<0.01).The mRNA levels of ANP,BNP and β-MHC were downregulated(P<0.01).The ROS production and gp91 phox protein levels were reduced in the Hyp+TAC group(P<0.01),while the protein levels of Nrf2,HO-1 and SOD2 increased(P<0.01).However,ML385 could partially reverse the protective effects of Hyp on TAC-induced cardiac hypertrophy.Conclusion Hyp alleviates pressure overload-induced cardiac hypertrophy by inhibiting oxidative stress and fibrosis,and its mechanism may be related to Nrf2/HO-1 signaling.
7.Research progress on the correlation between imaging characteristics and pathological invasion degree of early lung adenocarcinoma
Yantao YANG ; Yunchao HUANG ; Guangqiang ZHAO ; Lianhua YE
Chinese Journal of Clinical Thoracic and Cardiovascular Surgery 2023;30(09):1337-1343
With the development of multi-slice spiral computed tomography (CT) technology and the popularization of low-dose spiral CT screening, more and more adenocarcinomas presenting ground-glass nodule (GGN) are found. Pathological invasiveness is one of the important factors affecting the choice of treatment strategy and prognosis of patients with early lung adenocarcinoma. Imaging features have attracted wide attention due to their unique advantages in predicting the pathologic invasiveness of early lung adenocarcinoma. The imaging characteristics of GGN can be used to predict the pathologic invasiveness of lung adenocarcinoma and provide evidence for clinical decisions. However, the imaging parameters and numerical values for predicting pathologic invasiveness are still controversial, which will be reviewed in this paper.
8.Effects of organ dose modulation technique on image quality and radiation dose in sinus CT scanning
Dewu YANG ; Yan SUI ; Kang LIU ; Yantao NIU
Chinese Journal of Radiological Medicine and Protection 2022;42(3):230-234
Objective:To investigate the effects of organ dose modulation (ODM) on image quality and radiation dose to lens during sinus CT scanning.Methods:The GE Revolution EVO CT was used to scan the anthropomorphic head with ODM turned off as the control group and ODM turned on as the observation group. With different parameter combinations of tube voltage (140, 120, 100 kV), noise index (N17, N18), pitch (0.531, 0.969 at 20 cm collimation width, 0.516, 0.984 at 40 mm collination width), 24 series of images were acquired respectively. The tube current (mA) valuesat the anterior (A), left (L), posterior (P) and right (R) positions, volume CT dose index (CTDI vol) and dose length product (DLP) were recorded. Average CT values (AV), standard deviation (SD), signal-to-noise ratio (SNR), contrast to noise ratio (CNR) and image quality factor (FOM) of ROI were calculated. Double blind method was used to evaluate the edge sharpness, soft tissue level, noise and artifact on a subjective scale of 3 points. Results:For the combinations of different scanning parameters, the radiation dose of the observation group was lower than that of the control group. The tube current attheposition A for the observation group was lower than that of the control group, and the difference was statistically significant ( t=2.28, P<0.05). The differences oftube currentsatposotions of L, P and R, CTDI vol and DLP values in twogroupswere not statistically significant ( P>0.05). There were no significant differences in SD, SNR, CNR and FOM between the two groups of images ( P>0.05). There were no significant differences in the subjective scores of edge sharpness, soft tissue gradation, noise and artifacts between the two groups ( P>0.05). Conclusions:ODM technique can effectively reduce the radiation dose of eye lens without decompromising the image quality, which could meet the requirements of diagnosis, and accord with the principle of radiological protection optimization.
9.Establishment of Quality Standard for Benchmark Samples of Liangditang
Yantao WANG ; Chunyan WANG ; Xiaodan QI ; Haibin LIU ; Zhongchao WANG ; Haiju YANG ; Liyan QIAN ; Lingmei KONG ; Yan LIU
Chinese Journal of Experimental Traditional Medical Formulae 2022;28(20):27-36
ObjectiveTo establish the quality standard of Liangditang benchmark samples. MethodUltra performance liquid chromatography-quadrupole time-of-flight mass spectrometry (UPLC-QTOF-MS) was used to qualitatively analyze the chemical composition of Liangditang on the basis of molecular and fragment ion peak information with cracking law. The mobile phase was methanol (A)-0.05% phosphate aqueous solution (B) for gradient elution (0-10 min, 5%-23.5%A; 10-20 min, 23.5%A; 20-58 min, 23.5%-63%A; 58-60 min, 63%-90%A), the flow rate was 0.8 mL·min-1, and the detection wavelength was 254 nm. Electrospray ionization was employed under positive ion mode, the detection range was m/z 100-1 700. Key quality attributes and sources were determined by comparing with single medicine and reference substances. Through mass transfer analysis of multiple batches from decoction pieces to benchmark samples, high performance liquid chromatography (HPLC) for determining the contents of index components and HPLC detection of characteristic maps were established. Through the determination of 15 batches of benchmark samples, the content range of the index components and the common peaks of the characteristic map were determined. Thin layer chromatography (TLC) was applied to the identification of 5 medicines in the formula. Moisture and dry extract yield of the benchmark samples were determined by drying method. ResultA total of 27 compounds were inferred from the benchmark samples of Liangditang, among which 9 compounds were confirmed by comparison with the control, including catalpol, harpagide, gallic acid, albiflorin, paeoniflorin, verbascoside, angoroside C, cinnamic acid and harpagoside. A method for determining the characteristic maps of the benchmark samples were established and 13 peaks were assigned, and the characteristic peaks were mainly derived from wine-processed products of Rehmanniae Radix, Scrophulariae Radix and wine-processed products of Paeoniae Radix Alba. The similarity between the characteristic map of 15 batches of benchmark samples and the control characteristic map was >0.9. Methods for the determination of paeoniflorin, harpagoside, L-hydroxyproline and glycine were established, and the contents of these four components in 15 batches of benchmark samples were within ±30% of the corresponding mean value, and the transfer rate of decoction pieces to the benchmark samples was stable and controllable. TLC was established to identify 5 prescription drugs (except Ejiao) with two kinds of test solutions, and the results showed that the method had good specificity. The average dry extract yield was 48.06%, and the average moisture was 5.58%, which were within the range of ±10% and ±30% of their mean values, respectively. ConclusionThe quality standard of Liangditang benchmark samples was as follows:the similarity between the benchmark samples and the control characteristic map is >0.9, the contents of paeoniflorin, harpagoside, L-hydroxyproline and glycine are 217-403, 24-46, 634-1 178, 1 253-2 328 mg per dose, the dry extract yield is 43.0%-53.0%, the moisture is 4.0%-7.0%, under the set detection conditions, the benchmark samples have corresponding characteristic spots by comparing with the control herbs of 5 medicines. This quality standard is stable and reliable, which fills the gap in the quality control of Liangditang, and can provide a reference for the establishment of the quality standard of Liangditang granules.
10.Study on image quality optimization of abdominal digital radiography with different additional filters
Yan SUI ; Dewu YANG ; Xunru LI ; Junfeng SONG ; Kang LIU ; Zhaorui CHEN ; Yantao NIU
Chinese Journal of Radiological Medicine and Protection 2021;41(7):519-523
Objective:To investigate the effect of different additional filters on the image quality and radiation dose in abdominaldigital radiography (DR).Methods:Retrospective analysis was performed on 10 cases of abdominal DR from December 2020 to January 2021 in Fuxing Hospital, and the average mAs was calculated. Using automatic exposure control (AEC) technology, a polymethyl methacrylate (PMMA) slab of the corresponding thickness (18 cm) at the same output of above mAs was confirmed and used as the attenuator to simulate the abdomen. The phantom of CDRAD 2.0 and 17 slices of 10 mm thick PMMA plates (total thickness 18 cm) were placed on the bed. The additional filters were selected as no additional filter, 2 mmAl, 0.1 mmCu+ 1 mmAl, 0.1 mmCu+ 2 mmAl respectively. The AEC levels were selected at -2, -1, 0, 1, and 2 respectively. The images were collected and analyzed by using CDRAD 2.0 software to obtain the image quality factor (IQF inv). The incident air kinetic energy on the surface of the PPMA was measured for each exposure, and PCXMC software was used to estimate the organ dose and effective dose, and a comparative analysis was made. Results:The skin incident doses at no additional filter, 2 mmAl, 0.1 mmCu+ 1 mmAl, 0.1 mmCu+ 2 mm Al were (0.546 1±0.200 8), (0.376 2±0.133 8 ), (0.285 3±0.100 1) and (0.289 9±0.099 2) mGy, respectively. The estimated effective doses were (79.63±29.24)×10 -3, (71.05±25.56)×10 -3, (63.58±22.18)×10 -3 and (67.64±23.11)×10 -3 mSv, respectively. The gonadal doses were (0.058 1±0.020 8), (0.050 0±0.018 0), (0.044 8±0.015 6) and (0.047 7±0.016 3) mGy.The IQF inv values were 4.70±0.61, 4.80±0.84, 4.60±0.55, 4.60±0.60, respectively. There were linear correlations between the effective dose and the skin incident dose under different additional filtration, and the effective doses increased with the increase of the incident doses. The dose was lowest at the addition filtration of 0.1 mmCu+ 1 mmAl. There was no significant difference in the IQF inv between groups( P>0.05). Conclusions:The optimal additional filtration for abdominal DR was 0.1 mmCu+ 1 mmAl with the image quality meeting the requirements of clinical diagnosis, the radiation dose reduced reasonably, and the objective of the optimization of radiographic parameters achieved.

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