To investigate the automatic synthesis process of 2-¹⁸F-fluorobutyric acid (2-¹⁸F-FBA) and its C18 column purification method, so as to meet the production requirements of Good Manufacturing Practice of Medical Products (GMP), shorten the synthesis time and improve the yield. To evaluate the PET imaging of 2-¹⁸F-FBA in nude mice with prostate tumor.

Based on the GE TRACERlab FX-FN module, 2-¹⁸F-FBA was automatically synthesized by 'one-pot method' and 'column hydrolysis method', respectively. Both schemes used methyl 2-bromobutyrate as a precursor, which was fluorinated, purified and hydrolyzed to obtain 2-¹⁸F-FBA. Micro-PET/CT was performed at different time points after tail vein injection of 2-¹⁸F-FBA in nude mice bearing prostate tumor, and the PMOD software was used to outline the region of interest and calculate the maximum standardized uptake value.

The synthesis time of 2-¹⁸F-FBA by 'one-pot method' and 'column hydrolysis method' was 35 min and 27 min, respectively, and the uncorrected radiochemical yield was (34±5.2)% and (41±3.7)%. Micro-PET/CT showed significant radio-concentration at the tumor at 30 min after injection of 2-¹⁸F-FBA, and the tumor / muscle ratio was relatively high at 60 min. Both schemes were able to synthesize 2-¹⁸F-FBA, with the 'column hydrolysis' method having a relatively shorter synthesis time and higher yield.

The 2-¹⁸F-FBA is clearly visualized in tumor of prostate tumor bearing nude mice with a high target/non-target ratio at 60 min.

To investigate the application of high-frequency ultrasound combined with CT in the early diagnosis of papillary thyroid carcinoma and its predictive value for cervical lymph node metastasis.

Clinical data of 120 patients with suspected papillary thyroid cancer admitted to the Fourth Affiliated Hospital of Xinjiang Medical University from January 2022 to July 2023 were retrospectively analyzed. All the patients underwent thyroidectomy and cervical lymph node dissection, and high-frequency ultrasound and CT examinations were performed. The pathological results were used as the gold standard to count the detection of papillary thyroid cancer and cervical lymph node metastasis by high-frequency ultrasound and CT alone and in combination, and the diagnostic value of high-frequency ultrasound and CT alone and in combination for papillary thyroid cancer and the predictive value for cervical lymph node metastasis were analyzed.

Among the 120 patients with suspected papillary thyroid carcinoma, 107 (89.17%) were positive for papillary thyroid carcinoma and 13 (10.83%) were negative; 65 (54.17%) had metastasis in the cervical lymph nodes and 55 (45.83%) did not have metastasis. High-frequency ultrasound detected 72 true-positive and 9 true-negative papillary thyroid carcinomas; CT detected 74 true-positive and 10 true-negative; and combined examinations detected 89 true-positive and 11 true-negative cases. Using the pathologic results as the gold standard, high-frequency ultrasound detected 49 true-positive and 43 true-negative cervical lymph node metastases; CT detected 51 true-positive and 44 true-negative; and combined examination detected 61 true-positive and 52 true-negative. ROC curve analysis showed that the sensitivity, accuracy, and AUC of the combined high-frequency ultrasound and CT examination were higher than those of the high-frequency ultrasound and CT single examination for diagnosing papillary thyroid carcinoma (P<0.05); the sensitivity, specificity, positive predictive value, negative predictive value, accuracy, AUCs of the combined high-frequency ultrasound and CT examination for predicting cervical lymph node metastasis were higher than those of the high-frequency ultrasound, CT single examination (P<0.05).

The value of high-frequency ultrasound combined with CT for early diagnosis of papillary thyroid cancer was high, and it could predict the metastasis of the patient's cervical lymph nodes, and the combined examination of the two was better than the examination alone.

To assess the relationship between symptoms and cerebral perfusion in patients with unilateral internal carotid artery occlusion (ICAO), and the influence of the occlusion period and location on cerebral perfusion.

Sixteen patients with ICAO who met the inclusion and exclusion criteria were enrolled in the Department of Neurology of the Second Affiliated Hospital of Xi'an Jiaotong University from September 2021 to March 2023. Regional cerebral blood flow (CBF) was measured by Dr Brain's software ASL module. Differences in regional CBF in global, middle cerebral artery (MCA) territory, anterior cerebral artery territory, Alberta Stroke Programme Early Computed Tomography Score (ASPECTS) regions (include caudate nucleus, lentiform nucleus, insula ribbon, internal capsule and M1-M6) and brain lobes (include frontal, parietal, temporal, insular lobe) of different subgroups (symptomatic and asymptomatic, acute and chronic, initial and intracranial ICAO) at PLD 1.5 s and PLD 2.5 s were evaluated.

The CBF of symptomatic and asymptomatic, acute and chronic, initial and intracranial ICAO patients found no differences in the global and contralateral hemisphere at PLD 1.5 s and PLD 2.5 s (P>0.05). The CBF of initial and intracranial ICAO patients found no differences in the ipsilateral hemisphere at PLD 1.5 s and PLD 2.5 s (P>0.05). In the occluded hemisphere, the CBF of symptomatic ICAO was significantly lower than that of asymptomatic at PLD 1.5 s in M5, the CBF of symptomatic was significantly higher than that of asymptomatic at PLD 1.5 s in internal capsule (P<0.05). The CBF of symptomatic and asymptomatic ICAO found no differences in the ipsilateral hemisphere at PLD 2.5 s (P>0.05). In the occluded hemisphere, the CBF of acute ICAO was significantly lower than that of chronic at PLD 1.5 s in middle cerebral artery territory, M1, M5, frontal lobe; the CBF of acute ICAO was significantly lower than that of chronic at PLD 2.5 s in middle cerebral artery territory, M1, M5, M6, frontal lobe (P<0.05).

Acute ICAO has further perfusion impairment than chronic ICAO in the middle cerebral artery territory and partly ASPECTS cortical areas of the occluded side. Symptomatic ICAO was associated with further perfusion impairment in partly ASPECT area of the occluded side. There was no significant difference in cerebral perfusion at different locations of internal carotid artery occlusion.

To investigate the correlation between the pathogenic distribution of hospital-acquired pneumonia (HAP) and ventilator- associated pneumonia (VAP) with their corresponding chest CT imaging characteristics, aiming to promptly identify the distribution of HAP/VAP pathogens and accurately assess the extent of pulmonary lesions.

A retrospective analysis was performed for the culture of airway secretion pathogens and chest CT images of 184 patients with HAP/VAP (154 cases of HAP and 30 cases of VAP) who were diagnosed and treated at the Affiliated Hospital of Shaanxi University of Chinese Medicine from January 2020 to January 2022. Artificial intelligence software was used to segment chest CT images and quantitatively analyze pathogenic bacteria image characteristics. The quantitative indicators included whole lung volume, emphysema quantification, lesion volume, lesion volume percentage, lesion mass, and the percentage of lesion density less than -300 HU in total lesion volume.

Gram-negative bacilli were the dominant pathogens (92.72%), with Klebsiella pneumoniae, Pseudomonas aeruginosa, Acinetobacter baumannii being the most prevalent. Surgical history/invasive procedures emerged as major risk factors in 37% of the patients. On CT images, lung consolidation was a common funding, while Klebsiella pneumoniae pneumonia showed pleural effusion and ground- glass changes; Pseudomonas aeruginosa pneumonia also shows bronchiectasis and cavitation; Acinetobacter baumannii pneumonia may also see pleural effusion and interstitial changes. Quantitative CT analysis revealed that LAA- 950% in patients with Klebsiella pneumoniae pneumonia was low, whereas it was higher in patients with mixed bacterial infection. Patients with Klebsiella pneumoniae pneumonia have the biggest lung volume, whereas those with mixed infections caused by bacteria have the least. The highest proportion of LOA% in pneumonia, combined with a fungal infection (15%), was observed in patients. And LOA% was 10.5%, which could indicate the presence of fungal infection or multiple bacterial infections, with an area under the curve of 0.713 (P=0.041), 79% sensitivity, and 70% specificity.

By analyzing the CT imaging features and quantitative parameters of HAP/VAP, especially LOA%, it is helpful to speculate on potential pathogenic bacterial types, which has important value in the diagnosis of combined fungal or multi bacterial infections.

To explore the diagnostic value of susceptibility-weighted imaging (SWI) combining transcranial sonography (TCS) in Parkinson's disease (PD).

Forty-two PD patients treated at the First People's Hospital of Foshan from January 2021 to December 2023 were selected as the PD group, while 43 healthy volunteers served as the control group. All subjects underwent SWI and TCS examinations to observe the disappearance of the "swallow tail sign" in the midbrain substantia nigra. Differences in the hyperechoic area of the substantia nigra (SN), midbrain area, and the S/M values were analyzed between the groups. Statistically significant indicators were subjected to multivariate logistic regression analysis to identify independent predictors of PD and construct a predictive model, which was visualized using a nomogram. The model's discriminative ability, calibration, and clinical utility were evaluated using ROC curves, calibration curves, and decision curve analysis, respectively.

There were significant differences in the hyperechoic area of the SN (P<0.001) and the S/M ratio (P<0.001) between the PD group and the control group. The AUC for SWI and TCS separately in distinguishing PD from control group were 0.80 (95% CI: 0.716-0.886) and 0.857 (95%CI: 0.774-0.940), respectively. Multivariate Logistic regression analysis showed that the hyperechoic area of SN and the swallow tail sign as independent risk factors for predicting PD. The predictive model constructed using these factors had an AUC value of 0.94 (95% CI: 0.896-0.984). The calibration curve demonstrated good agreement between predicted and actual probabilities, and decision curve analysis showed that the predictive model provided a higher net benefit than individual indicators.

The predictive model combining SWI and TCS quantitative indicators demonstrates good predictive capability for PD risk, surpassing any single model and showing promising clinical utility.

To explore the hardness study of shear wave elastography (SWE) on closed complete Achilles tendon rupture.

Fifty- three patients with closed complete Achilles tendon rupture diagnosed by ultrasound in the First Hospital of the University of Science and Technology of China from July 2021 to January 2024 were selected, and the separation length of the Achilles tendon rupture, the length of the rupture site from the attachment site and the thickness of the Achilles tendon were measured ultrasonographically, as well as the proximal and distal Achilles tendon rupture and the healthy Achilles tendon shear wave velocity (SWV), and the SWV of the flounder muscle of both the affected and the healthy side were measured simultaneously.

The 53 cases of closed patients with complete Achilles tendon rupture, 62.26% (33/53) of the Achilles tendon ruptures occurred on the left side and 37.73% (20/53) of the Achilles tendon ruptures occurred on the right side. Side-by-side comparisons of the thickness of the ruptured Achilles tendon on the affected side, the thickness of the Achilles tendon on the healthy side, the length of the rupture from the attachment, and the length of the separation of the Achilles tendon on the affected side were not statistically significant (P > 0.05); the thicknesses of the distal part of the rupture of the Achilles tendon on the affected side and that of the Achilles tendon on the healthy side were 8.36±3.07 mm and 5.01±0.97 mm, respectively, with statistically significant differences (P < 0.05), the thicknesses of the proximal part of the rupture of the Achilles tendon on the affected side and the Achilles tendon on the healthy side, the The differences in SWV between the proximal part of the affected Achilles tendon rupture and the proximal part of the affected Achilles tendon rupture and the distal part of the affected Achilles tendon rupture were statistically significant (P < 0.05), and the differences in SWV between the healthy Achilles tendon flounder muscle and the affected ruptured Achilles tendon flounder muscle were not statistically significant (P > 0.05).

Closed complete rupture of the Achilles tendon mostly involves the left Achilles tendon, and the elastic changes of the affected Achilles tendon occur in the free Achilles tendon and do not involve the proximal tendon structures of the flounder muscle, and the SWE technique can be used to quantitatively assess the preoperative stiffness of the affected Achilles tendon.

To investigate the value of conventional ultrasound signs and shear-wave elastography elastic ratio (SWE-ER) in predicting the risk of cervical lymph node metastasis (CLNM) in papillary thyroid carcinoma (PTC) invasion.

Eighty-seven patients with PTC confirmed by postoperative pathology from June 2022 to March 2024 in Baoji People's Hospital were collected, including 93 cancer nodules. The patients were divided into CLNM group and non-CLNM group according to postoperative pathology. The characteristics of conventional ultrasound images of the relationship between thyroid cancer nodules and the capsule (the contact between cancer nodules and the capsule, the continuity of the capsule, and the invasion range of the capsule) and the SWE-ER value were retrospectively analyzed. ROC curves of the relationship between SWE-ER, nodules and the capsule at different thresholds were drawn by pathological diagnosis as the gold standard, and the value of predicting the risk of cervical lymph node metastasis at different thresholds was compared. Independent risk factors for CLNM were calculated by binary Logistic regression equation.

The average meridian of cancer nodules in CLNM group was higher than that in non- CLNM group (P < 0.05). Compared with non- CLNM, there were statistically significant differences in capsule contact, capsule continuity and capsule invasion area in the perituberous length of cancer in CLNM group (P < 0.001). The mean value of SWE-ER in the CLNM group was lower than that in the non-CLNM group (P < 0.05). Using pathology as the gold standard, ROC curves were developed to assess the risk of CLNM under different cut-off values. The area under the ROC curve with the capsule invasion occupying 1/4 of the circumference of cancer nodules as cut-off value was 0.756(95% CI: 0.652- 0.859), indicating the highest diagnostic efficiency. Multivariate analysis by binary Logistic regression showed that thyroid capsule interruption, capsule invasion in 1/4-1/2 of the circumference of cancer nodule, capsule invasion in ≥ 1/2 of the circumference of cancer nodule were independent risk factors for CLNM (P < 0.05). The contact between SWE-ER and the capsule of cancer nodules was not an independent risk factor for CLNM of PTC (P > 0.05).

The relationship between thyroid cancer nodule and capsule, especially the invasion range of thyroid cancer nodule capsule has high diagnostic value in ultrasonic prediction of CLNM. The involvement of the capsule in 1/4-1/2 of the circumference of cancer nodule, and the involvement of the capsule in ≥1/2 of the circumference of cancer nodule were independent risk factors for CLNM, while SWE-ER and whether cancer nodule contacted with the capsule were not independent risk factors for CLNM in PTC.

To analyze the independent prognostic factors of postoperative patients with stage ⅡA colorectal cancer and construct a prediction model.

A total of 4847 patients with a diagnosis of stage ⅡA colorectal cancer with concomitant surgical treatment registered at the American Cancer Center from January 1, 2010 to December 31, 2015 were collected according to the SEER database, and the Kaplan-Meier method was applied to draw the survival curves, and the COX proportional risk model was applied to analyze the factors affecting the prognosis of postoperative patients with stage ⅡA colorectal cancer and to construct a prediction model.

Univariate COX regression analysis suggested that six factors, including patient age, tumor site, nerve invasion, number of lymph nodes cleared, carcinoembryonic antigen level and adjuvant chemotherapy, were the influencing factors of patients' overall survival (P < 0.001). Multifactorial analysis identified five independent risk factors associated with overall survival, which were age, nerve invasion, number of lymph nodes cleared, carcinoembryonic antigen level and adjuvant chemotherapy (P < 0.001). Accordingly, survival curves were plotted and stratified for patients with different neuroinvasive status, and both patients with PNI(+) and PNI(-) showed improved prognosis after adjuvant chemotherapy, but the difference between the two groups was not statistically significant (P=0.652). Based on the results of the multifactorial COX analysis, a column-line diagram was constructed, and the ROC curve showed that the column- line diagram could accurately predict the survival rates of patients with stage ⅡA colorectal cancer after surgery at 1 year (AUC=0.727), 3 years (AUC=0.697), and 5 years (AUC=0.692). AUCs of the 1-, 3-, and 5-year survival rates in the test set were 0.760, 0.722, 0.704, respectively.

The column-line graphical model can provide a basis for prognostic and therapeutic decision-making in postoperative patients with stage ⅡA colorectal cancer.

To explore the value of multi-slice spiral CT in the differential diagnosis of cecal diverticulitis and acute appendicitis.

A total of 128 cases of suspected acute appendicitis admitted to the First Affiliated Hospital of Changsha Medical College, Linxiang People's Hospital and Yiyang Third People's Hospital from January 2020 to September 2023 were retrospectively analyzed. All patients underwent CT plain scan and 3D reconstruction image processing before surgery. With postoperative pathological results or discharge diagnosis as the gold standard, the clinical application value of three- dimensional reconstruction of multi- slice spiral CT in the diagnosis of cecal diverticulitis and acute appendicitis was deeply explored, and the key points of differentiation between the two were analyzed.

Among the 128 patients, 49 cases of acute appendicitis, 41 cases of cecal diverticulitis, 21 cases of acute appendicitis combined with cecal diverticulitis and 17 cases of normal people were confirmed by operation, pathology or discharge treatment. The accuracy of three-dimensional multi-slice CT in the diagnosis of cecal diverticulitis was 96%. The accuracy of diagnosis of acute appendicitis was 98.25%. The accuracy of diagnosis of acute appendicitis with cecal diverticulitis was 100%. CT signs: The proportion of appendicitis enlargement in patients with acute appendicitis was significantly higher than that with cecal diverticulitis, with statistical significance (P < 0.05). 89.80% of appendicitis patients had periappendicular exudation but no exudation around the cecum, 82.93% of cecal diverticulitis patients had periappendicular exudation but no exudation around the appendix.

Multi-slice spiral CT 3D reconstruction technique has high efficacy in the differential diagnosis of acute appendicitis and cecal diverticulitis, and can provide guidance for the selection of clinical treatment.

To observe the prenatal diagnosis and prognosis analysis of vena cava anomalies fetuses from multiple perspectives, and to provide experience for integrated maternal-fetal management.

A total of 105 fetuses born in the first affiliated Hospital of University of Science and Technology of China from 2021 to 2023 were retrospectively analyzed. According to the abnormal development of vena cava, the fetuses were divided into two groups: abnormal vena cava group (n=51) and normal vena cava group (n=54). The routine prenatal data and pregnancy outcome of the two groups were analyzed to explore the influencing factors of adverse pregnancy outcome of abnormal vena cava.

There was significant difference in adverse pregnancy outcome between abnormal vena cava fetus and normal fetus (P < 0.05). The incidence of adverse pregnancy outcome of abnormal vena cava fetus was higher than that of normal fetus. There was significant difference in adverse pregnancy outcome among isolated vena cava abnormal fetus, intracardiac abnormal fetus and extracardiac abnormal fetus (P < 0.05). There was significant difference in adverse pregnancy outcome between isolated vena cava abnormal fetus and intracardiac abnormal fetus (P < 0.05). There was no significant difference in adverse pregnancy outcome between isolated vena cava abnormal fetus and extracardiac abnormal fetus, extracardiac abnormal fetus and intracardiac abnormal fetus (P > 0.05). There was no significant correlation between maternal age, common complications during pregnancy and adverse pregnancy outcome of abnormal vena cava fetus (P > 0.05). Intracardiac malformation was an important influencing factor of adverse pregnancy outcome of abnormal vena cava fetus (P < 0.05).

The adverse pregnancy outcomes of fetuses with vena cava anomalies differed from those of normal fetuses, and the combination of intracardiac malformations was a risk factor for the adverse pregnancy outcomes of fetuses with vena cava anomalies.

To evaluate the diagnostic value of CT imagomics in hepatic fibrosis in patients with chronic hepatitis B (CHB).

A total of 210 patients with CHB admitted to Xinjiang Uygur Autonomous Region People's Hospital from January to October in 2023 were selected as the study subjects. Patients were divided into non-fibrosis group (n=137) and fibrosis group (n=73). All patients underwent CT plain scan + enhanced scan. Shukun Radiomics V 94 software was used to extract different CT imagomics features from the region of interest of each CT image, including texture feature, shape feature, filter feature, density feature, etc. The enrolled patients were divided into training set (n=147) and validation set (n=63), and the diagnostic model of liver fibrosis in CHB patients was screened and established by LASSO and Logistic regression analysis. The performance of the model was evaluated using the ROC curve.

After LASSO screening, 23 of the 1227 extracted quantitative image features were retained to construct the diagnostic model of liver fibrosis in CHB patients. The AUC, accuracy, sensitivity, and specificity of the training set were 0.851, 0.789, 0.792, and 0.735, respectively; The AUC, accuracy, sensitivity, and specificity of the validation set were 0.774, 0.733, 0.751, and 0.703, respectively.

The CT image-omics features show clinical significance in the assessment of liver fibrosis in patients with CHB.

To evaluate abdominal visceral fat (VAT) and subcutaneous fat (SAT) by quantitative CT, and to explore the correlation between abdominal fat distribution and colorectal adenoma.

A total of 100 patients with colorectal adenoma diagnosed by pathology in Foshan First People's Hospital from January 2022 to July 2023 were retrospectively collected as the adenoma group. The adenomas were divided into early adenomas (n=36) and advanced adenomas (n=64). Then, 158 healthy people without adenoma in our hospital during the same period were collected as the normal group. Basic clinical data were collected, and quantitative CT was used to measure the VAT and SAT areas at the L2/3 intervertebral space level in the abdomen. The fat distribution of the adenoma group was compared with the normal group and the adenoma groups of different pathological types. Logistic regression analysis was used to evaluate the correlation between VAT, SAT and the risk of colorectal adenoma.

The VAT area of the adenoma group was higher than that of the normal group (P=0.015), while the difference in SAT was not statistically significant (P > 0.05), the VAT area of the advanced adenoma group was higher than that of the early adenoma (P=0.021). Logistic regression analysis showed. Age, hyperlipidemia, BMI, VAT and VAT obesity were independent risk factors for colorectal adenoma (OR=2.044, 1.325, 1.147, 1.895, 2.185, P < 0.05).

VAT is associated with the incidence of colorectal adenoma. The higher VAT, the higher risk of adenoma and more likely it is to develop into advanced adenoma. However, SAT is not necessarily associated with the occurrence of adenoma.

To explore the clinical value of B1-corrected T1 mapping in the diagnosis of benign and malignant lung nodules and the identification of the pathological types of lung cancer.

Fifty-four patients with a total of 57 lung nodules underwent chest B1- corrected T1 mapping were collected in Yancheng No.1 People's Hospital from August 2020 to July 2022, including 17 cases of benign and 40 cases of malignant lung nodules. The native T1 values of lesions were manually measured by two independent radiologists (observers A and B). The intra- and inter-observer reproducibility were evaluated with intraclass correlation coefficients. The differences of T1 values between the benign and malignant lung nodules were compared. ROC curves were identified the best threshold value for distinguishing the benign and malignant lung nodules. The native T1 values among different pathological types of lung cancer were compared by one-way analysis of variance.

The native T1 values of lung nodules showed good reproducibility both within and between observers (intraclass correlation coefficients=0.977, 0.953). The native T1 values of benign pulmonary nodules measured by observers A and B were 1615.98± 337.28 ms and 1618.52±362.82 ms, respectively. The native T1 values of malignant pulmonary nodules measured by observers A and B were 1376.87 ± 262.50 ms and 1392.51 ± 301.30 ms, respectively. The native T1 values of benign lung nodules was significantly higher than those of malignant lung nodules (P=0.006 and 0.020). ROC curve analysis showed that when the threshold value was 1350.33 ms, the sensitivity and specificity of the diagnosis of malignant pulmonary nodules were 53.66% and 87.50%, and the AUC was 0.720 (95% CI: 0.586-0.831). The native T1 values were different among adenocarcinoma, squamous cell carcinoma and small-cell lung cancer (observer A and B: P=0.009 and P=0.010). The native T1 values of small-cell lung cancer were significantly higher than those of adenocarcinoma and squamous cell carcinoma (P=0.003 and P=0.049), but there was no statistically significant difference between adenocarcinoma and squamous cell carcinoma (P=0.944 and P=0.774).

B1-corrected T1 mapping is a rapid, non-invasive quantitative imaging technique with a good repeatability that can be used to distinguish between benign and malignant lung nodules and identify the pathological types of lung cancer.

To investigate the feasibility of DRI combined with waist circumference in reducing radiation dose of lumbar CT examination in children.

A total of 300 children who underwent lumbar spine CT examination at the Children's Medicine Affiliated to Nanjing Medical University from January 2021 to October 2022 were divided into groups according to their waist circumferences, with a waist circumference of ≤45 cm for group A, a waist circumference of 45-50 cm for group B, and a waist circumference of > 50 cm for group C, the children in each group were randomly assigned to different subgroups, each subgroup corresponded to different DRI values, the scanning tube voltage was 100 kV, the DoseRight automatic exposure control technology was used, the iDose4 reconstruction algorithm was used to reconstruct the CT images, and the quality of the images were subjectively and objectively evaluated, and the CTDIVOL and DLP of each group were compared and analyzed.

When the DRI of group A was 9, group B was 11, and group C was 13, the image quality can meet the minimum diagnostic requirements, the SNR in the intervertebral disc region and the paravertebral muscle region of the three groups increased with the increase of DRI, and the difference was statistically significant (P < 0.01), the CTDIVOL and DLP of the three groups decreased with the decrease of DRI (P < 0.01).

The combination of DRI and waist circumference can provide guidance for the development of an individualized plan for lumbar CT scan in children.

To analyze the prognostic factors of gastrointestinal stromal tumors after radical surgery for 5 years and establish a survival prediction model to guide clinical practice.

A retrospective analysis was conducted on the clinical, pathological, and CT data of 297 patients with gastrointestinal stromal tumors who underwent radical surgery at our Hospital from January 5, 2010 to June 20, 2018. With a 5-year observation cut-off point, they were divided into non recurrence survival group (n=232) and death or recurrence metastasis group (n=65). A Logistic regression model was established by combining statistically significant clinical, pathological, and CT features, and the model efficacy was evaluated.

The relationship between clinical pathological characteristics and 5-year prognosis of patients: Patients without adjuvant imatinib treatment, with high mitotic count, and high Ki-67 index have a higher probability of poor prognosis within 5 years, and the difference was statistically significant (P < 0.05); However, gender, age, and gastrointestinal bleeding had no statistically significant difference in 5-year prognosis (P > 0.05). The relationship between CT features and 5-year prognosis: There were statistically significant differences between the two groups in terms of location, shape, size, cystic change or necrosis, rupture, bleeding, tumor with cystic lumen communicating with the intestinal canal, is there a large blood supply artery or drainage vein, venous phase and delayed phase enhancement methods (P < 0.05); However, there was no statistically significant difference in growth mode, ulcer, calcification and transient enhancement of the overlying mucosal line (P > 0.05); Logistic regression combining clinical pathology and CT features: Tumor location, morphology, size, tumor rupture, tumor sac to intestinal communication, and mitotic imaging were independent predictors of 5-year prognosis. The AUC was 0.916, sensitivity was 0.877, specificity was 0.802, and accuracy was 0.818, all of which were higher than the subjective predictions of two radiologists.

This study established a predictive model that affects the 5-year prognosis of gastrointestinal stromal tumors after radical surgery. The predictive performance of this model is good, providing important basis for accurate judgment and evaluation of the 5-year prognosis of gastrointestinal stromal tumors in clinical practice.