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1.
Arq. bras. cardiol ; Arq. bras. cardiol;121(4): e20230565, abr.2024. graf
Article in Portuguese | LILACS-Express | LILACS | ID: biblio-1557048

ABSTRACT

Resumo A doença veno-oclusiva pulmonar (DVOP) e a hemangiomatose capilar pulmonar são tipos raros de substratos histopatológicos dentro do espectro da hipertensão arterial pulmonar (HAP) com prognóstico muito ruim. Caracterizam-se por um processo fibroproliferativo generalizado das veias e/ou capilares de pequeno calibre com preservação das veias maiores, resultando em um fenótipo de hipertensão pulmonar pré-capilar. A apresentação clínica é inespecífica e semelhante a outras etiologias de HAP. O diagnóstico definitivo é obtido por meio de análise histológica, embora a biópsia pulmonar não seja aconselhada devido ao maior risco de complicações. No entanto, alguns achados adicionais podem permitir um diagnóstico clínico presuntivo de DVOP, especialmente história de tabagismo, uso de drogas quimioterápicas, exposição a solventes orgânicos (particularmente tricloroetileno), baixa capacidade de difusão do monóxido de carbono (DLCO), dessaturação ao esforço e evidências de doença venosa sem doença cardíaca esquerda no exame de imagem, manifestada por uma tríade clássica de opacidades em vidro fosco, linhas septais, e linfadenopatias. O transplante pulmonar é o único tratamento eficaz e os pacientes devem ser encaminhados no momento do diagnóstico, devido à rápida progressão da doença e ao prognóstico ruim. Apresentamos o caso de um homem de 58 anos com HAP com características de envolvimento venoso/capilar em que a suspeita clínica, o pronto diagnóstico e o encaminhamento precoce para transplante pulmonar foram determinantes para um bom desfecho.


Abstract Pulmonary veno-occlusive disease (PVOD) and pulmonary capillary hemangiomatosis are rare types of histopathological substrates within the spectrum of pulmonary arterial hypertension (PAH) with a very poor prognosis. They are characterized by a widespread fibroproliferative process of the small caliber veins and/or capillaries with sparing of the larger veins, resulting in a pre-capillary pulmonary hypertension phenotype. Clinical presentation is unspecific and similar to other PAH etiologies. Definitive diagnosis is obtained through histological analysis, although lung biopsy is not advised due to a higher risk of complications. However, some additional findings may allow a presumptive clinical diagnosis of PVOD, particularly a history of smoking, chemotherapy drug use, exposure to organic solvents (particularly trichloroethylene), low diffusing capacity for carbon monoxide (DLCO), exercise induced desaturation, and evidence of venous congestion without left heart disease on imaging, manifested by a classical triad of ground glass opacities, septal lines, and lymphadenopathies. Lung transplant is the only effective treatment, and patients should be referred at the time of diagnosis due to the rapid progression of the disease and associated poor prognosis. We present a case of a 58-year-old man with PAH with features of venous/capillary involvement in which clinical suspicion, prompt diagnosis, and early referral for lung transplantation were determinant factors for the successful outcome.

2.
Chinese Journal of Radiology ; (12): 57-63, 2024.
Article in Chinese | WPRIM | ID: wpr-1027292

ABSTRACT

Objective:To investigate the value of CT radiomic model based on analysis of primary gastric cancer and the adipose tissue outside the gastric wall beside cancer in differentiating stage T1-2 from stage T3-4 gastric cancer.Methods:This study was a case-control study. Totally 465 patients with gastric cancer treated in Affiliated People′s Hospital of Jiangsu University from December 2011 to December 2019 were retrospectively collected. According to postoperative pathology, they were divided into 2 groups, one with 150 cases of T1-2 tumors and another with 315 cases of T3-4 tumors. The cases were divided into a training set (326 cases) and a test set (139 cases) by stratified sampling method at 7∶3. There were 104 cases of T1-2 stage and 222 cases of T3-4 stage in the training set, 46 cases of T1-2 stage and 93 cases of T3-4 stage in the test set. The axial CT images in the venous phase during one week before surgery were selected to delineate the region of interest (ROI) at the primary lesion and the extramural gastric adipose tissue adjacent to the cancer areas. The radiomic features of the ROIs were extracted by Pyradiomics software. The least absolute shrinkage and selection operator was used to screen features related to T stage to establish the radiomic models of primary gastric cancer and the adipose tissue outside the gastric wall beside cancer. Independent sample t test or χ2 test were used to compare the differences in clinical features between T1-2 and T3-4 patients in the training set, and the features with statistical significance were combined to establish a clinical model. Two radiomic signatures and clinical features were combined to construct a clinical-radiomics model and generate a nomogram. The area under the receiver operating characteristic curve (AUC) was used to evaluate the efficacy of each model in differentiating stage T1-2 from stage T3-4 gastric cancer. The calibration curve was used to evaluate the consistency between the T stage predicted by the nomogram and the actual T stage of gastric cancer. And the decision curve analysis was used to evaluate the clinical net benefit of treatment guided by the nomogram and by the clinical model. Results:There were significant differences in CT-T stage and CT-N stage between T1-2 and T3-4 patients in the training set ( χ2=10.59, 15.92, P=0.014, 0.001) and the clinical model was established. After screening and dimensionality reduction, the 5 features from primary gastric cancer and the 6 features from the adipose tissue outside the gastric wall beside cancer established the radiomic models respectively. In the training set and the test set, the AUC values of the primary gastric cancer radiomic model were 0.864 (95% CI 0.820-0.908) and 0.836 (95% CI 0.762-0.910), and the adipose tissue outside the gastric wall beside cancer radiomic model were 0.782 (95% CI 0.731-0.833) and 0.784 (95% CI 0.702-0.866). The AUC values of the clinical model were 0.761 (95% CI 0.705-0.817) and 0.758 (95% CI 0.671-0.845), and the nomogram were 0.876 (95% CI 0.835-0.917) and 0.851 (95% CI 0.781-0.921). The calibration curve reflected that there was a high consistency between the T stage predicted by the nomogram and the actual T stage in the training set ( χ2=1.70, P=0.989). And the decision curve showed that at the risk threshold 0.01-0.74, a higher clinical net benefit could be obtained by using a nomogram to guide treatment. Conclusions:The CT radiomics features of primary gastric cancer lesions and the adipose tissue outside the gastric wall beside cancer can effectively distinguish T1-2 from T3-4 gastric cancer, and the combination of CT radiomic features and clinical features can further improve the prediction accuracy.

3.
Chinese Journal of Radiology ; (12): 165-171, 2024.
Article in Chinese | WPRIM | ID: wpr-1027296

ABSTRACT

Objective:To investigate the consistency of myocardial extracellular volume between systole and diastole using dual-layer detector spectral CT.Methods:This was a cross-sectional study. Thirty-five patients who underwent cardiac spectral CT examination in West China Hospital of Sichuan University from April 2022 to December 2022 were retrospectively collected. Hematocrit was collected within 3 days before the CT scan. The delayed phases holographic spectral images in systole (45%) and diastole (75%) were obtained using dual-layer spectral CT. CT data were processed using a spectral post-processing workstation, and the extracellular volume (ECV) based on iodine density images, referred as CT-ECV, in systolic and diastolic phases were calculated, respectively. According to the American Heart Association′s 16-segment model of left ventricular, the standard short-axis images were constructed, and the myocardium was standardized into 16 segments at the basal, mid-cavity, and apical levels of the left ventricle. Two radiologists performed a subjective evaluation in the image quality of the CT-ECV images of the whole heart and the three sections in systole and diastole using a "five-point" scale. The ECV of the 16 segments and the whole heart in systole and diastole was calculated. The consistency of subjective evaluations between systole and diastole was assessed using Kappa statistics. Wilcoxon signed-rank tests were used to compare the differences in scores between systole and diastole. Paired sample t-test was used to compare the differences in CT-ECV scores between systole and diastole. The intraclass correlation coefficient was used to test the intra-and inter-observer consistency of CT-ECV measurements between two radiologists. P<0.05 was statistically significant. Results:There was good agreement between the two radiologists on subjective scores of CT-ECV image quality between systole and diastole ( Kappa>0.80), and there was no statistical difference in image quality among the basal, mid-cavity, and apical levels of the left ventricle and whole heart between systole and diastole ( P>0.05). The systolic and diastolic CT-ECV for the entire heart obtained through the delay phase were (33.29±3.46)% and (33.50±3.39)%, respectively, with no statistically significant difference ( t=-0.78, P=0.442). CT-ECV in systole and diastole were (34.15±3.94)% and (35.30±3.99)% for segment 8, (34.03±3.76)% and (35.46±3.74)% for segment 9, and (33.98±3.32)% and (35.05±3.98)% for segment 14, respectively. The mean values of the systolic CT-ECV of segments 8, 9 and 14 were significantly lower than those of diastolic CT-ECV ( t=-2.65, -3.26, -2.42, P=0.012, 0.003, 0.022, respectively). The ICCs for CT-ECV measurements of 16 segments by the two radiologists were greater than 0.90 in both systolic and diastolic, indicating good agreement. Conclusions:There is no significant difference in whole heart CT-ECV values between systolic and diastolic myocardial ECV based on dual-layer spectral CT. However, minor differences (less than 2%) are found between systolic and diastolic myocardial CT-ECV for some segments. Myocardial CT-ECV measurement should be performed on the same segment during the same phase to obtain stable and accurate ECV values.

4.
Chinese Journal of Radiology ; (12): 172-179, 2024.
Article in Chinese | WPRIM | ID: wpr-1027297

ABSTRACT

Objective:To investigate the value of the virtual monoenergetic image (VMI) obtained by a new dual-layer detector spectral CT combined with metal artifact reduction algorithms(O-MAR) in reduction of different types of artifacts caused by 125I seeds implantation and in improvement of the post-operative CT image quality. Methods:This was a cross-sectional study. Thirty-five patients who underwent dual-layer detector spectral CT scanning of the chest and abdomen after 125I seeds implantation were retrospectively included at the First Affiliated Hospital of Zhengzhou University from March to September 2022. The spectral data were collected and reconstructed into conventional CT image (CI), VMI image (50-150 keV, 20 keV/level), CI+O-MAR image, and VMI+O-MAR image (50-150 keV, 20 keV/level). The artifacts′ removal effects and image quality improvement in each group were evaluated. Two slices with the strongest artifacts were selected for analysis for each patient, resulting in a total of 70 slices. Objective indicators including artifact index (AI), signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) of soft tissue regions affected by artifacts were measured and calculated. Subjective indicators including the overcorrected artifacts and new artifacts, the different forms of artifacts, the diagnosis of artifacts, and the image quality were assessed. One-way analysis of variance was used for comparisons among multiple groups. Paired t test was used to compare the quantitative indicators between the combined O-MAR group and the non-O-MAR group. Kappa statistics was used to evaluate the consistency between observers. Results:In high/low-density artifacts (ROI H/L), the AI values in all groups showed decrease with increasing VMI keV. In artifact-affected tissue (ROI T), SNR of the CI/VMI (70-150 keV)+O-MAR group were significantly higher than those of the CI/VMI group ( P<0.05), CNR of the CI/VMI(50-150 keV)+O-MAR group were significantly higher than those of the CI/VMI group ( P<0.05). Both overcorrection and new artifacts mainly presented in VMI 50 keV and VMI 70 keV groups; Compared with VMI (50-70 keV) group, significantly less numbers of overcorrection and new artifacts were found in VMI (50-70 keV)+O-MAR group ( P<0.05); regarding the comparison of artifact types, with the VMI keV increasing, the number of a-type banded artifacts gradually decreased on images with high-density artifacts, reaching a minimum of 3 in the VMI 150 keV+O-MAR group; while the number of e-type artifacts with little or no artifacts increased, with the highest number of 23 in the VMI 150 keV+O-MAR group. The total number of high-density artifacts in each type decreased with increasing VMI keV. As VMI keV increased, the diagnostic and image quality scores of high-density artifacts in each group were significantly higher than those of low-density artifacts in the VMI+O-MAR group ( P<0.05). Conclusions:VMI combined with O-MAR can significantly improve the objective and subjective image quality of follow-up CT imaging after 125I seed implantation, enhancing lesion visibility and diagnostic confidence. Additionally, VMI+O-MAR showed more pronounced correction effect on high-density artifacts.

5.
Chinese Journal of Radiology ; (12): 180-186, 2024.
Article in Chinese | WPRIM | ID: wpr-1027298

ABSTRACT

Objective:To investigate the value of multi-parametric analysis based on dual-layer detector spectral CT (DLCT) in predicting the initial recurrence risk for papillary thyroid carcinoma (PTC).Methods:From November 2021 to October 2022, 102 PTC patients confirmed by pathology were retrospectively collected at the First Affiliated Hospital of Nanjing Medical University in this cross-sectional study. There were 25 males and 77 females, with an age of (42±13) years old. The initial recurrence risk assessment for PTC patients was categorized into a low-risk group (75 cases) and an intermediate-high-risk group (27 cases). Clinical data, including age, gender, body mass index, history of nodular goiter, history of Hashimoto thyroiditis, and preoperative thyroid function, were collected. Tumor morphological features, including size, location, shape, aspect ratio, the degree of thyroid capsule contact, calcification, and cystic change, were evaluated. Quantitative DLCT parameters, including iodine concentration (IC), standardized iodine concentration (NIC), effective atomic number (Z eff), standardized effective atomic number (NZ eff), electronic density (ED), CT values under different energy levels (40-200 keV, 30 keV intervals) and slope of energy spectrum curve (λ HU) both in the arterial and venous phase were measured. The differences in clinical, morphological features, and spectral CT quantitative parameters between the two groups were compared using independent sample ttest, Mann-Whitney U test, or χ2 test. Multivariate logistic regression analyses were used to construct three models based on clinical and morphological features, quantitative DLCT parameters and their combination, respectively. The receiver operating characteristic curve was used to evaluate the predictive performance of these models for the initial recurrence risk of PTC patients, and the area under the curve (AUC) was compared using the DeLong test. Results:Significant differences were found in gender, lesion long diameter, lesion short diameter and calcification between the low-risk group and intermediate-high-risk groups ( P<0.05). The arterial phase IC, arterial phase Z eff, arterial phase λ HU, arterial phase CT 40 keV, venous phase NIC and venous phase NZ eff in intermediate-high-risk group were significantly lower than those in the low-risk group ( P<0.05). The logistic regression analysis revealed that the clinical model included gender ( OR=2.895, 95% CI 1.047-8.002, P=0.040) and lesion long diameter ( OR=1.142, 95% CI 1.042-1.251, P=0.004), with an AUC of 0.720, sensitivity of 63.0%, and specificity of 78.7% in predicting the initial recurrence risk of PTC patients. The DLCT quantitative parameter model included arterial phase IC ( OR=0.580, 95% CI 0.370-0.908, P=0.017), venous phase NIC ( OR=0.077, 95% CI 0.011-0.536, P=0.010), and venous phase NZ eff ( OR=0.002, 95% CI 0.001-0.103, P=0.009), with an AUC of 0.774, sensitivity of 71.9%, and specificity of 70.0%. The AUC of the combined model was 0.857, with a sensitivity of 74.1%, and specificity of 88.0%, outperforming the clinical model ( Z=2.92, P=0.004) and the DLCT quantitative parameter model ( Z=2.07, P=0.046). Conclusion:Multi-parametric analysis based on DLCT can help predict the initial recurrence risk for PTC, and combining it with clinical and morphological features, the predictive accuracy can be improved.

6.
Chinese Journal of Radiology ; (12): 187-193, 2024.
Article in Chinese | WPRIM | ID: wpr-1027299

ABSTRACT

Objective:To explore the value of nomogram based on dual-layer detector spectral CT quantitative parameters and conventional CT feature in evaluating high-grade pattern (HGP) of pulmonary invasive non-mucinous adenocarcinoma.Methods:This study was a case-control study. A total of 71 patients with pathologically confirmed pulmonary invasive non-mucinous adenocarcinoma in the First Affiliated Hospital of Soochow University from February 2022 to May 2023 were retrospectively enrolled, which were divided into HGP and non-HGP groups according to pathological results. Conventional CT features were analyzed, including size, shape, density, internal signs, margins, and pleural retraction. The iodine concentration (IC), electron density (ED), and normalized iodine concentration (NIC) of the lesions in both the arterial phase (AP) and venous phase (VP) were measured. Differences between the two groups were analyzed using independent sample t-test, Mann-Whitney U test, or χ2 test. Multivariate logistic regression analysis was used to select the independent influencing factors of HGP in pulmonary invasive non-mucinous adenocarcinoma, and the conventional CT feature model, the spectral CT quantitative parameter model, and the combined model were constructed and expressed in a nomogram. The area under the curve (AUC) of receiver operating characteristic curve was used to assess the performance of each model, and was compared by DeLong test. Decision curves (DCA) was used to assess the clinical net benefit of the models. Results:There were significant differences between HGP group and non-HGP group in terms of density, lobulation, spiculation, IC AP, IC VP, NIC AP, ED AP and ED VP (all P<0.05). The multivariate logistic regression analysis showed that the solid nodule ( OR=15.452, 95% CI 4.246-56.235, P<0.001), lobulation ( OR=7.069, 95% CI 1.618-30.883, P=0.009), ED AP( OR=1.183, 95% CI 1.064-1.315, P=0.002) and IC VP ( OR=0.231, 95% CI 0.072-0.744, P=0.014) were independent influencing factors for predicting HGP in pulmonary invasive non-mucinous adenocarcinoma. The AUC of the conventional CT feature model, spectral CT quantitative parameter model, and the combined model were 0.835, 0.890, and 0.915, respectively. The AUC of the combined model was better than that of the conventional CT feature model ( Z=2.67, P=0.008). The DCA analysis demonstrated that the nomogram had higher clinical net benefit than the conventional CT feature model. Conclusions:The nomogram based on the quantitative parameters of dual-layer detector spectral CT and conventional CT features have favorable diagnostic efficacy in predicting HGP in pulmonary invasive non-mucinous adenocarcinoma, and can be used as a reliable tool for non-invasive diagnosis of HGP before surgery.

7.
Chinese Journal of Radiology ; (12): 194-200, 2024.
Article in Chinese | WPRIM | ID: wpr-1027300

ABSTRACT

Objective:To explore the value of dual-layer detector spectral CT quantitative parameters in evaluating the treatment response of neoadjuvant chemoradiotherapy (nCRT) in patients with locally advanced rectal cancer (LARC).Methods:The study was a cross-sectional study. From May 2021 to March 2023, a total of 52 patients with LARC who received complete nCRT and were pathologically confirmed rectal adenocarcinoma at the Guangdong Province Hospital of Traditional Chinese Medicine were retrospectively enrolled. Each patient underwent spectral CT examination before and after nCRT, including plain scan, arterial phase (AP), and venous phase (VP) scans. According to the tumor regression grade, the patients were divided into the good response ( n=20) and the poor response group ( n=32). Measurements of the primary tumor′s spectral CT parameters, including effective atomic number (Z eff) at plain scan, iodine concentration (IC), CT values of 40 keV and 100 keV virtual monochromatic image (VMI) at dual-enhanced phases, were taken before and after nCRT. Additionally, the normalized iodine concentration (NIC), spectral curve slope (λHU), and the change rate of the above parameters before and after nCRT were calculated. The independent sample t-test or Mann-Whitney U test was used to compare the differences between the two groups. The receiver operating characteristic (ROC) curve was used to assess the efficacy of various metrics in evaluating the tumor treatment response of nCRT. A binary logistic regression analysis of combined parameter results was performed for the parameters with the areas under curve (AUC)>0.75, and the AUC of the combined parameter was evaluated. Results:There were significant differences in NIC AP and λHU VP before nCRT, NIC VP and λHU VP after nCRT, and the change rates of Z eff, NIC AP, NIC VP and λHU AP between the good response group and the poor response group ( P<0.05). The remaining parameters showed no statistically significant difference ( P>0.05). The ROC curve results showed that the AUCs of the above 8 parameters for evaluating tumor treatment response of nCRT were 0.702, 0.655, 0.695, 0.769, 0.738, 0.807, 0.791, and 0.677, respectively. The AUC of the combined model of the three parameters with AUC>0.75 (λHU VP after nCRT, the change rate of NIC AP and NIC VP) was 0.869, with 80.0% sensitivity and 84.4% specificity. Conclusion:The quantitative parameters derived from spectral CT may provide new markers for evaluating the response to nCRT treatment in patients with LARC. The multi-parameter combined model can improve diagnostic efficacy.

8.
Chinese Journal of Radiology ; (12): 209-215, 2024.
Article in Chinese | WPRIM | ID: wpr-1027302

ABSTRACT

Objective:To explore the value of radiomics and deep learning in predicting the efficacy of initial transarterial chemoembolization (TACE) for hepatocellular carcinoma (HCC).Methods:This was a cohort study. The imaging and clinical information of HCC patients treated with TACE in the Second Affiliated Hospital of Harbin Medical University from January 2015 to January 2021 were collected retrospectively. A total of 265 patients were divided into response group (175 cases) and non-response group (90 cases) according to the modified solid tumor efficacy evaluation criteria (mRECIST) 1 to 2 months after initial TACE. According to the proportion of 8∶2, the patients were randomly divided into training group (212 cases, 140 responders and 72 non-responders) and test set (53 cases, 35 responders and 18 non-responders). Univariate and multivariate logistic regression was used to screen clinical variables and construct a clinical model. The radiomics features were extracted from the preoperative CT images, and radiomics model was constructed after feature dimensionality reduction. Using the deep learning method, three residual network (ResNet) models (ResNet18, ResNet50 and ResNet101) were established, and their effectiveness was compared and integrated to build a deep learning model with best performance. Univariate and multivariate logistic regression was used to combine pairwise three models to establish the combined model. The receiver operating characteristic curve was used to evaluate the performance of the model to distinguish between TACE response and non-response groups.Results:In the test set, the area under the curve (AUC) of the clinical model and the radiomics model in the differentiation between response and non-response after TACE were 0.730 (95% CI 0.569-0.891) and 0.775 (95% CI 0.642-0.907). The AUC of ResNet18, ResNet50 and ResNet101 were 0.719, 0.748 and 0.533, respectively. The AUC for deep learning model obtained by integrating ResNet18 and ResNet50 was 0.806 (95% CI 0.665-0.946). After pairwise fusion, the combined deep learning-radiomics model showed the highest performance, with an AUC of 0.843 (95% CI 0.730-0.956), which was better than those of the deep learning-clinical model (AUC of 0.838, 95% CI 0.719-0.957) and the radiomics-clinical model (AUC of 0.786, 95% CI 0.648-0.898). Conclusions:The combined model of radiomics and deep learning has high performance in predicting the curative effect of TACE in patients with HCC before operation.

9.
Chinese Journal of Radiology ; (12): 273-278, 2024.
Article in Chinese | WPRIM | ID: wpr-1027306

ABSTRACT

Objective:To investigate the clinical value of multiparametric myocardial imaging using a dual-layer detector spectral CT in the non-invasive preoperative assessment of patients with coronary atherosclerotic heart disease (CHD) undergoing percutaneous coronary intervention (PCI).Methods:The clinical and imaging data of 90 patients who underwent coronary CT angiography (CCTA) with dual-layer spectral detector CT and invasive coronary angiography (ICA) within 30 days at the Affiliated Changshu Hospital of Nantong University from January 2021 to October 2022 were retrospectively analyzed. A total of 189 coronary arteries were included in the study cohort. The patients were divided into PCI ( n=44) and non-PCI groups ( n=46) according to whether they received PCI after evaluation with ICA. The diameter stenosis rate of the coronary arteries, myocardial iodine concentration (IC) and effective atomic number (Z eff) values were obtained from CCTA conventional and spectral images. The IC values and Z eff values of the myocardium in the areas with abnormal perfusion were compared with those in the areas with normal perfusion. The diagnostic performance of these parameters, as well as their combined model, was evaluated and compared using receiver operating characteristic (ROC) curve and area under the curve (AUC) in the pre-PCI assessment of patients with CHD. Results:Baseline patient data did not show statistically significant differences between the PCI and non-PCI groups (all P>0.05). There were statistically significant differences in IC values [(0.42±0.28) and (2.26±0.48) mg/ml] and Z eff values (7.39±0.33 and 8.50±0.25) between the myocardium areas with abnormal perfusion and the myocardium areas with normal perfusion in all patients (all P<0.001). The AUC for assessing whether patients with CHD need PCI treatment using myocardial IC and Z eff values were 0.865 and 0.853, respectively, which were significantly higher than assessment based only on lumen diameter stenosis rate (AUC=0.726, P<0.001). Conclusions:The IC and Z eff derived from myocardial spectral images can be used to diagnose myocardial perfusion abnormalities in patients with CHD. The spectral myocardial multi-parameters imaging shows promising potentials in pre-PCI assessment of patients with CHD, which can improve the efficiency of evaluation and may help to avoid unnecessarily invasive procedures.

10.
Chinese Journal of Radiology ; (12): 286-292, 2024.
Article in Chinese | WPRIM | ID: wpr-1027308

ABSTRACT

Objective:To investigate the value of the nomogram based on quantitative parameters of dual-layer detector spectral CT and conventional CT features in preoperatively predicting tumor deposits (TDs) in colorectal cancer.Methods:This study was a case-control study. A total of 126 patients with pathologically confirmed colorectal cancer who underwent preoperative spectral CT scan from January 2022 to March 2023 in the First Affiliated Hospital of Soochow University were enrolled retrospectively. Patients were divided into TDs-positive group ( n=38) and TDs-negative group ( n=88) based on pathological results. The following conventional CT features were assessed: cT stage, cN status, uniformity of enhancement in the venous phase, pericolorectal fat invasion (PFI), maximum tumor diameter, and tumor location. The following quantitative parameters were also measured and calculated: the normalized iodine concentration (NIC) of lesions, the normalized effective atomic number (NZ eff), and the slope of the 40-100 keV spectral curve (K) in the arterial and venous phases, and the difference in NIC between the arterial and venous phases. Multivariate logistic regression analysis was used to select independent predictors of TDs and the nomogram based on spectral CT quantitative parameters and conventional CT features was constructed. The receiver operating characteristic curve was performed to evaluate the diagnostic performance of each parameter and model. DeLong test was used to compare the differences of area under the curve (AUC). Results:Statistically significant differences were found between the TDs-positive and TDs-negative groups for the cT stage, cN status, uniformity of enhancement in the venous phase, PFI, NIC, NZ eff, K in the venous phase and the difference in NIC between the arterial and venous phases ( P<0.05). After multivariate logistic regression analysis, the conventional CT feature model incorporated two features: uniformity of enhancement in the venous phase (OR=9.602, 95% CI 3.728-24.734, P=0.001) and PFI ( OR=2.881, 95% CI 1.177-7.049, P=0.020). The combined model of conventional CT features and spectral CT quantitative parameters incorporated three features: the difference in NIC between the arterial and venous phases ( OR=37.599, 95% CI 8.320-169.912, P=0.001), uniformity of enhancement in the venous phase ( OR=14.978, 95% CI 3.848-58.295, P=0.001), and PFI ( OR=4.013, 95% CI 1.320-12.760, P=0.015), and the nomogram was constructed. The AUC, sensitivity, and specificity of the nomogram for predicting TDs were 0.919 (95% CI 0.865-0.973), 84.2%, and 86.5%, respectively. The AUC of the conventional CT feature model was 0.796 (95% CI 0.707-0.885), which was lower than that of the nomogram, and the difference was statistically significant ( Z=3.87, P=0.001). Conclusion:Dual-layer spectral detector CT can be used to predict TDs in colorectal cancer preoperatively, and the nomogram based on quantitative parameters of dual-layer detector spectral CT and conventional CT features shows good diagnostic performance.

11.
Chinese Journal of Radiology ; (12): 409-415, 2024.
Article in Chinese | WPRIM | ID: wpr-1027318

ABSTRACT

Objective:To establish and validate a clinical and CT radiomics combined model for predicting lymph node metastasis (LNM) risk in patients with hilar cholangiocarcinoma (HCCA).Methods:This was a case-control study. Data from 158 pathologically confirmed HCCA patients between January 2016 and January 2022 at the First Affiliated Hospital of Zhengzhou University were retrospectively analyzed. Using stratified random sampling, the patients were randomly divided into a training set ( n=95) and an internal validation set ( n=63) at a 6∶4 ratio. According to postoperative pathology, 31 LNM-positive cases and 64 LNM-negative cases were in the training set, and 22 LNM-positive cases and 41 LNM-negative cases were in the internal validation set. A cohort of 50 HCCA patients was retrospectively collected from West China Hospital of Sichuan University between October 2018 and June 2021 as an external validation set, including 21 LNM-positive and 29 LNM-negative cases. Clinical features were selected by multivariate logistic regression analysis to establish a clinical model. Radiomics features were extracted from portal venous phase CT images using 3D Slicer software. A radiomics model was developed using the least absolute shrinkage and selection operator regression algorithm. A clinical-radiomics model was constructed by integrating clinical features and Radscore, and a nomogram was developed. The prediction performance of models was evaluated by the area under the receiver operating characteristic curve (AUC). The AUC values were compared using the DeLong test. Calibration curves and decision curves were plotted to assess calibration and clinical net benefit. Results:Clinical N (cN) staging was an independent risk factor for LNM ( OR=6.86, 95% CI 2.70-18.49, P<0.001). Totally 12 optimal features were selected to construct the radiomics model, and the clinical-radiomics nomogram model was constructed by combining cN staging and Radscore. In the external validation set, the AUC (95% CI) of the clinical model, radiomics model, and clinical-radiomics nomogram were 0.706 (0.576-0.836), 0.768 (0.637-0.899), and 0.803 (0.680-0.926), respectively. The nomogram achieved higher AUC than clinical and radiomics models with statistical significance ( Z=2.01, 2.21; P=0.044, 0.027). The calibration and decision curves demonstrated good model fit, providing clinical net benefits for patients. Conclusion:The clinical-radiomics nomogram model combining cN staging and CT radiomics features can effectively predict LNM risk in HCCA patients.

12.
Article in Chinese | WPRIM | ID: wpr-1027414

ABSTRACT

Objective:To investigate the clinical value of prospective ECG-gated high-pitch protocol scanning of third generation DSCT in the diagnosis of pediatric congenital heart disease (CHD).Methods:A total of 243 children with confirmed CHD who were expected to undergo surgical treatment were prospectively collected and randomly divided evenly into 3 groups, with first group for prospective ECG-gated high-pitch scanning in third generation DSCT (Flash 3rd), second group for prospective ECG-gated high-pitch scanning in second generation DSCT (Flash 2nd) and third group for prospective sequential scanning in third generation DSCT (Sequence 3rd). The SD value and SNR of aortic root and pulmonary artery of each child were recorded. The 5-point system is adopted with subjective scoring. Based on the result of operation, the diagnosis accuracy in 3 groups was analyzed. Results:The E values in Flash 3rd, Flash 2nd and Sequence 3rd group were 0.24 (0.19, 0.27), 0.11 (0.10, 0.14) and 0.44 (0.39, 0.48) mSv ( H=207.04, P<0.05), respectively. Subjective scores of group Flash 3rd and Sequence 3rd were significantly higher than that of group Flash 2nd [4 (4, 4) vs. 4(3, 4) vs. 3(3, 3), H=124.05, P<0.05] and no difference between these two groups. SD value of aortic root and pulmonary artery of group Flash 3rd and Sequence 3rd were significantly lower than that of group Flash 2nd( H= -40.27-33.38, P<0.05). SNR of aortic root and pulmonary artery of group Flash 3rd was significantly higher than that of group Flash 2nd and Sequence 3rd ( H=-0.90-51.42, P<0.05). Diagnosis accuracy of intracardiac malformation for group Flash 2nd was significantly lower than that of Flash 3rd and Sequence 3rd (77.7%, 90.9%, 88.9%, K=9.36, P<0.05), and there was no significant difference between the latter two groups. There was no difference in diagnosis accuracy of extracardiac malformation among 3 groups (88.6%, 94.8%, 92.2%, K=3.11, P=0.21). Conclusions:The prospective ECG-gated high-pitch scanning in third generation DSCT can take into account radiation dose and image quality, which has important clinical value in the diagnosis of CHD.

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Article in Chinese | WPRIM | ID: wpr-1027589

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Objective:To study the CT manifestations of malignant hepatic perivascular epithelioid cell carcinoma (PEComa).Methods:Clinical data of nine patients undergoing surgery with histologically confirmed malignant hepatic PEComa in Yueqing People's Hospital, Wenzhou People's Hospital, and Yongjia County People's Hospital from January, 2010 to June, 2022 were retrospectively collected, including two males and seven females with a median age of 47 (43, 56) years old. The CT findings, including tumor size, shape, boundary, density, and enhancement patterns, were analyzed.Results:CT scans showed that all nine tumors were single lesions. Five tumors were located in right liver lobe, three in left lobe, and one in caudate lobe. The median tumor diameter was 5.7 (range, 3.3-16.0 ) cm. In terms of tumor shape, three were round, four were quasi-circular, and two were irregular. Eight tumors had well-defined boundaries, while one was ill-defined. Nine tumors showed uneven densities and were lower than the adjacent liver parenchyma. Four tumors had a false capsule, one contained fatty tissue, and six had necrotic and cystic changes. In the arterial phase of contrast-enhanced CT scanning, two tumors showed moderate enhancement and seven showed significant enhancement. In the portal venous and delayed phases, enhancement decreased significantly in four cases, showing a " fast-in and fast-out" pattern. In four cases, the enhancement persisted, showing a " fast-in and slow-out" pattern. One case showed no enhancement in any phase but had a strip-like enhanced vessel inside the tumor. Five cases had significantly thickened vessels around the tumor.Conclusion:The CT manifestations of PEComa are as follows: round or quasi-circular lesions with well-defined boundaries, uneven low densities, significant enhancement in the arterial phase and rapid washout or persistent enhancement in the portal venous and delayed phases.

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Article in Chinese | WPRIM | ID: wpr-1027907

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Objective:To investigate the value of traditional metabolic parameters, CT features and intratumoral heterogeneity parameters measured by 18F-FDG PET/CT in predicting the mutation status of the epidermal growth factor receptor (EGFR) gene in patients with adenocarcinoma. Methods:A total of 147 patients (73 males, 74 females, age (59.8±10.2) years) with pathological confirmed adenocarcinoma between January 2016 and June 2020 in the Affiliated Hospital of Jining Medical University were retrospectively included. The differences of clinical data (smoking history, tumor location and clinical stage), CT features (maximum diameter, ground-glass opacity content, lobulation, speculation, cavitation, air-bronchogram, pleural retraction and bronchial cut-off sign), 18F-FDG PET/CT traditional metabolic parameters (SUV max, SUV mean, metabolic tumor volume (MTV) and total lesion glycolysis (TLG)) and intratumoral heterogeneity parameters ( CV, heterogeneity index (HI)) were analyzed between patients with EGFR mutation and patients with EGFR wild-type. Independent-sample t test, Mann-Whitney U test and χ2 test were used to analyze the data. Multivariate logistic regression was used to analyze the predictors of EGFR mutation. ROC curve analysis was used to evaluate the predictive value of clinical and PET/CT information. Results:Among 147 patients, 87 were with EGFR mutation and 60 were with EGFR wild-type. There were significant differences in gender (male/female), smoking history (with/without), location (peripheral lesion/central lesion), pleural retraction (with/without), SUV max, SUV mean, TLG, CV and HI ( χ2 values: 4.72-23.89, z values: from -2.31 to 5.74, all P<0.05). Multivariate logistic regression analysis showed that smoking history (odds ratio ( OR)=0.167, 95% CI: 0.076-0.366; P<0.001), pleural retraction ( OR=1.404, 95% CI: 1.115-3.745; P=0.012), SUV max ( OR=0.922, 95% CI: 0.855-0.995; P=0.003), TLG ( OR=0.991, 95% CI: 0.986-0.996; P=0.001) and HI ( OR=0.796, 95% CI: 0.700-0.859; P<0.001) were predictors of EGFR mutation. ROC curve analysis showed the AUC of HI was 0.779, with the sensitivity of 76.67%(46/60) and the specificity of 79.31%(69/87). The predictive model was constructed by combining smoking history, pleural retraction, TLG, SUV max and HI, and the AUC was 0.908, with the sensitivity of 88.33%(53/60) and the specificity of 68.97%(60/87). The difference of AUCs between HI and the predictive model was statistically significant ( z=3.71, P<0.001). Conclusion:HI can predict EGFR mutations better, and the predictive value for EGFR mutations can be enhanced when combining HI with smoking history, pleural retraction, TLG and SUV max.

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Article in Chinese | WPRIM | ID: wpr-1027909

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Objective:To investigate whether the image quality of total-body PET/CT (TB PET/CT) with 1 min acquisition can meet the clinical diagnostic requirements.Methods:From May 2019 to September 2021, a total of 90 malignant tumor patients (60 males, 30 females, age 31-86 years) with primary lesions confirmed by pathological diagnosis in Zhongshan Hospital, Fudan University were respectively analyzed. All patients underwent conventional PET/CT (C PET/CT) scan with conventional clinical acquisition and TB PET/CT scan with 1 min acquisition after injecting 18F-FDG in random order. Paired t test or Wilcoxon signed rank test was used to analyze the image quality of these two scans. Results:SUV max of primary lesions in TB PET/CT group was significantly higher than that in C PET/CT group (15.9(7.9, 24.6) vs 12.5(5.8, 16.6); z=8.14, P<0.001), so were signal-to-noise ratio (SNR) of the blood pool, liver, muscles (9.3±3.0, 11.4(9.5, 14.2), 8.3(7.3, 10.1) vs 6.2±1.7, 9.4(7.7, 11.8), 6.0(4.9, 7.1)), tumor-to-blood pool ratio (TBR) (9.3(4.3, 14.8) vs 8.5(4.3, 11.1)), tumor-to-liver ratio (TLR) (6.7(3.0, 10.4) vs 6.1(2.9, 7.7)), tumor-to-muscle ratio (TMR) (23.2(11.5, 38.0) vs 18.3(9.6, 26.6); t=9.36, z values: 4.44-7.40, all P<0.001). Conclusion:The image quality of TB PET/CT scan with 1 min acquisition can meet the diagnostic requirements, and is better than the C PET/CT image quality with conventional clinical acquisition.

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Article in Chinese | WPRIM | ID: wpr-1027912

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Objective:To explore whether multi-parametric MRI (mpMRI) combined with 68Ga-prostate specific membrane antigen (PSMA) PET/CT can improve the detection efficiency of clinically significant prostate cancer (csPCa). Methods:Clinical and imaging data of 152 patients (age (68.5±8.5) years) who underwent mpMRI and 68Ga-PSMA PET/CT examination for suspected prostate cancer in the First Affiliated Hospital of the Air Force Medical University from January 2021 to November 2022 were retrospectively analyzed, with the histopathological results from transrectal ultrasound guided biopsy as reference. Lesions with Gleason scores (GS) ≥3+ 4 from the biopsy were diagnosed with csPCa, and lesions with negative biopsy or GS 6 were diagnosed with non-csPCa. MpMRI was evaluated independently by two radiologists according to the Prostate Imaging Reporting and Data System (PI-RADS) version 2.1. The radioactive uptake of 68Ga-PSMA PET/CT in prostate lesions was evaluated by SUV max. The independent-sample t test, Mann-Whitney U test and χ2 test were used to compare differences between the two groups, and then multivariate logistic regression analysis was performed. ROC curves analysis was used to analyze the diagnostic efficacies of individual and combined factors and Delong test was used. Results:There were 85 csPCa and 67 non-csPCa confirmed. Prostate specific antigen (PSA), PI-RADS score and SUV max were significantly different between the csPCa group and the non-csPCa group ( χ2=68.06, U values: -7.66, -8.98, all P<0.001). Multivariate logistic regression analysis indicated that PI-RADS score (odds ratio ( OR)=3.424, 95% CI: 1.651-7.100) and SUV max ( OR=1.931, 95% CI: 1.403-2.658) were independent predictors of csPCa (both P<0.001). ROC curves analysis revealed that the cut-off value for diagnosing csPCa was 4 for PI-RADS score and 5.6 for SUV max. The accuracy of mpMRI and PET/CT alone in csPCa diagnosis was 80%(122/152) (AUC of 0.789(95% CI: 0.711-0.866) with the sensitivity and specificity of 91%(77/85) and 67%(45/67)), and 87%(132/152) (AUC of 0.876(95% CI: 0.817-0.936) with the sensitivity and specificity of 81%(69/85) and 94%(63/67)), respectively. Several joint models incorporating 68Ga-PSMA PET/CT with mpMRI data were investigated, the model of PI-RADS 5 or PI-RADS 3-4 and SUV max>5.6 showed better performance than mpMRI and PET/CT alone and other joint models ( z values: 2.01-3.64, all P<0.05), with the accuracy of 91%(138/152) (AUC of 0.910(95% CI: 0.857-0.962) with the sensitivity and specificity of 89%(76/85) and 93%(62/67)). Conclusion:MpMRI combined with 68Ga-PSMA PET/CT can significantly improve the detection efficiency of csPCa, with the principal effect being improved in risk stratification of PI-RADS 3-4 lesions in mpMRI.

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Article in Chinese | WPRIM | ID: wpr-1027919

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Objective:To evaluate the value of prostate specific membrane antigen (PSMA) PET/CT-based radiomics models in differentiation between prostate cancer and benign prostatic hyperplasia (BPH).Methods:Data from 50 patients with prostate cancer (age: (70.0±8.8) years) and 25 patients with BPH (age: (66.9±9.4) years) who underwent 18F-PSMA-1007 PET/CT imaging and prostate biopsy in the First Affiliated Hospital of Xi′an Jiaotong University from May 2020 to September 2022 were retrospectively collected. Patients were divided into the training set ( n=53) and test set ( n=22) in the ratio of 7∶3 by using random seed number. The ROIs were delineated based on PET and CT images, and radiomics features were extracted respectively. Feature selection was performed using the minimum redundancy and maximum relevance (mRMR) and the least absolute shrinkage and selection operator (LASSO) algorithm. PET and PET/CT radiomics models were generated using logistic regression. ROC curve analysis was employed for model evaluation. In addition, comparisons of the 2 radiomics models with parameters including the ratio of free prostate specific antigen (fPSA)/total prostate specific antigen (tPSA), PET metabolic parameters, as well as prostate cancer molecular imaging standardize evaluation (PROMISE) were conducted (Delong test). Results:A total of 7 features were included in the PET radiomics model, and 3 CT-based features and 4 PET-based features were included in the PET/CT radiomics model. The AUCs of PET and PET/CT radiomics models in the training set and test set were 0.941, 0.914 and 0.965, 0.914, respectively, which were higher than those of fPSA/tPSA (0.719 and 0.710), SUV max(0.748 and 0.800), peak of SUV (SUV peak, 0.722 and 0.771), metabolic tumor volume (MTV, 0.640 and 0.595), total lesion uptake (TLU, 0.525 and 0.476) and PROMISE (0.644 and 0.667)[ z values for the training set: from -6.26 to -3.13, all P<0.01; z values for the test set: from -3.16 to -1.08, P>0.05 (fPSA/tPSA, SUV max, SUV peak) or P<0.05 (MTV, TLU, PROMISE)]. The differential diagnostic accuracy, sensitivity and specificity of PET and PET/CT radiomics models in the test set were 86.36%(19/22), 13/15, 6/7 and 90.91%(20/22), 15/15, 5/7, respectively. Conclusion:Compared with the clinical and PET parameters, PSMA PET/CT-based radiomics model can further improve the efficiency of differential diagnosis between prostate cancer and BPH.

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Article in Chinese | WPRIM | ID: wpr-1027920

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Objective:To investigate the value of radiomics signatures based on 18F-FDG PET/CT for predicting molecular classification and Ki-67 expression of breast cancer. Methods:A total of 134 female patients ((55.4±13.3) years) who underwent 18F-FDG PET/CT examination and were diagnosed with breast cancer by pathology in the First Affiliated Hospital of Soochow University from April 2016 to May 2023 were retrospectively enrolled. LIFEx software was used to extract radiomics features and the least absolute shrinkage and selection operator (LASSO) algorithm and independent-sample t test were used to screen potentially meaningful features and calculate the radiomics score, which were considered as radiomics models. Clinical characteristics were selected by supervised logistic regression and clinical models were established. Radiomics features and clinical characteristics were incorporated to logistic regression analysis to establish combined models. ROC curves were drawn and the differences among AUCs were analyzed by Delong test. Results:Among 134 patients, 22 were with triple negative breast cancer (TNBC), 47 were human epidermal growth factor receptor 2 (HER2) over-expression type, 37 were Luminal A type and the rest 28 were Luminal B type. The expression of Ki-67 was high in 85 patients, and was low in the rest 49 patients. The AUCs (95% CI) of the combined models for predicting TNBC, HER2 overexpression type, Luminal A type and Ki-67 expression were 0.843(0.770-0.900), 0.808(0.723-0.876), 0.825(0.711-0.908) and 0.836(0.762-0.894), respectively, which were higher than those of clinical models ( z values: 1.97-3.06, all P<0.05). Conclusion:The predictive model combining radiomics signatures based on 18F-FDG PET/CT and clinical characteristics can well predict the molecular classification and Ki-67 expression level of breast cancer.

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Article in Chinese | WPRIM | ID: wpr-1027921

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Objective:To investigate the diagnostic value of machine learning model based on 18F-FDG PET/CT for polymyalgia rheumatica (PMR). Methods:From November 2014 to December 2022, 177 patients (119 males, 58 females; age: 67.0 ( 61.0, 72.0) years) admitted to the Department of Rheumatology and Immunology, the First People′s Hospital of Changzhou, with suspected PMR and undergoing 18F-FDG PET/CT examination were retrospectively analyzed. Patients were randomly divided into training set and validation set at the ratio of 7∶3. Three machine learning models, including classification and regression tree (CART), the least absolute shrinkage and selection operator (LASSO) algorithm, and logistic regression, were established based on the PET/CT imaging features to aid in the diagnosis of PMR. The diagnostic efficacy of each model was evaluated by ROC curve analysis and differences among AUCs were analyzed by Delong test. Results:There were 78(44.1%, 78/177) PMR patients and 99(55.9%, 99/177) non-PMR patients, and 124 patients in the training set and 53 patients in the validation set. The logistic regression model (training set: AUC=0.961; validation set: AUC=0.930) was superior to the CART (training set: AUC=0.902, z=2.96, P=0.003; validation set: AUC=0.844, z=2.46, P=0.014) in diagnosing PMR, and was similar to LASSO algorithm (training set: AUC=0.957, z=0.95, P=0.340; validation set: AUC=0.930, z=0.00, P=1.000), but with fewer sites evaluated. The simplified PMR-Logit score had the AUC of 0.951 in the overall population, with the sensitivity of 89.74%(70/78) and the specificity of 90.91%(90/99). Conclusion:Machine learning models based on 18F-FDG PET/CT imaging features are expected to be an effective diagnostic tool for PMR.

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Article in Chinese | WPRIM | ID: wpr-1027922

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Objective:To compare the imaging quality and metabolic quantitative parameters of pulmonary nodules between Q. Flex whole information five-dimensional (5D) and conventional three-dimensional (3D) PET/CT imaging for clinical evaluation.Methods:Fifty-four patients (30 males, 24 females, age: 60(42, 75) years; 78 solid pulmonary nodules (maximum diameter≤3 cm) with abnormal uptake of 18F-FDG) from Tianjin Cancer Hospital Airport Hospital between June 2022 and August 2022 were enrolled in this retrospective study. All patients underwent 5D scanning and 3D, 5D reconstruction. Image quality scores, signal-to-noise ratio (SNR), SUV max, SUV mean and metabolic tumor volume (MTV) of pulmonary nodules of 5D group and 3D group were evaluated and compared with χ2 test and Wilcoxon signed rank test. Correlation of quantitative parameters between 2 groups were analyzed by using Spearman rank correlation analysis. Results:Thirty-five of 78(45%) pulmonary nodules with image quality score≥4 were found in 5D group, which were more than those in 3D group (22/78(28%); χ2=4.67, P=0.031). Meanwhile, SNR, SUV max, SUV mean, and MTV were significantly positively correlated between the 2 groups ( rs values: 0.86, 0.86, 0.85, and 0.95, all P<0.001). SNR, SUV max and SUV mean of pulmonary nodules in 5D group were significantly higher than those in 3D group, which were 37.46(18.42, 62.00) vs 32.72(16.97, 54.76) ( z=-4.07, P<0.001), 9.71(5.48, 13.82) vs 8.96(4.82, 12.63) ( z=-3.05, P<0.001) and 6.30(3.39, 8.94) vs 5.61(2.99, 7.63)( z=-4.07, P<0.001) respectively. MTV of pulmonary nodules in 5D group was significantly lower than that in 3D group, which was 1.72(0.66, 2.74) cm 3vs 1.98(1.06, 4.63) cm 3 ( z=-7.13, P<0.001). Quantitative parameters of lower lung field and nodules with maximum diameters of >10 mm and ≤20 mm based on 5D scanning changed most significantly compared with those based on 3D scanning ( z values: from -5.23 to -2.48, all P<0.05). Conclusion:Q. Flex 5D PET significantly improves the quantitative accuracy of SUV and MTV of pulmonary nodules, and the improvement of image quality is substantial without increasing the radiation dose, which has clinical practical value.

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