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ObjectivesTo evaluate whether radiomics signature of pericoronary adipose tissue (PCAT) based on coronary computed tomography angiography (CCTA) could improve the prediction of future acute coronary syndrome (ACS) within 3 years.MethodsWe designed a retrospective case-control study that patients with ACS (n= 90) were well matched to patients with no cardiac events (n= 1496) during 3 years follow-up, then which were randomly divided into training and test datasets with a ratio of 3:1. A total of 107 radiomics features were extracted from PCAT surrounding lesions and 14 conventional plaque characteristics were analyzed. Radiomics score, plaque score, and integrated score were respectively calculated via a linear combination of the selected features, and their performance was evaluated with discrimination, calibration, and clinical application.ResultsRadiomics score achieved superior performance in identifying patients with future ACS within 3 years in both training and test datasets (AUC = 0.826, 0.811) compared with plaque score (AUC = 0.699, 0.640), with a significant difference of AUC between two scores in the training dataset (p= 0.009); while the improvement of integrated score discriminating capability (AUC = 0.838, 0.826) was non-significant. The calibration curves of three predictive models demonstrated a good fitness respectively (allp> 0.05). Decision curve analysis suggested that integrated score added more clinical benefit than plaque score. Stratified analysis revealed that the performance of three predictive models was not affected by tube voltage, CT version, different sites of hospital.ConclusionCCTA-based radiomics signature of PCAT could have the potential to predict the occurrence of subsequent ACS. Radiomics-based integrated score significantly outperformed plaque score in identifying future ACS within 3 years.Key Points• Plaque score based on conventional plaque characteristics had certain limitations in the prediction of ACS.• Radiomics signature of PCAT surrounding plaques could have the potential to improve the predictive ability of subsequent ACS.• Radiomics-based integrated score significantly outperformed plaque score in the identification of future ACS within 3 years.

BACKGROUND: The identification of patients with a high likelihood of left ventricular (LV) remodeling with a high-risk prognosis has critical implications for risk stratification after acute ST-segment elevation myocardial infarction (STEMI). This study aimed to evaluate the relationship between circulating miR-1 and 6-month post-infarct LV remodeling based on cardiac magnetic resonance (CMR) imaging. METHODS: A total of 80 patients with a first STEMI treated with primary percutaneous coronary intervention (PCI) who underwent CMR imaging 1 week and 6 months after STEMI were evaluated. The percentage changes of LV ejection fraction (LVEF), LV end-diastolic volume (LVEDV), LV end-systolic volume index (LVESV) at 1 week and 6 months after PCI (%ΔLVEF, %ΔLVEDV and %ΔLVESV) were calculated. miR-1 was measured using polymerase chain reaction (PCR)-based technologies in plasma samples that were collected at admission. The study group was divided into two groups based on a 10% cutoff value for the percentage of change in the LV end-diastolic volume (%ΔLVEDV): remodeling at high risk of major adverse cardiac events (MACEs) (%ΔLVEDV ≥10%, termed the LV remodeling group) and remodeling at lower risk of MACEs (%ΔLVEDV

The purpose of this study is to investigate the performance of dual-layer detector spectral CT for iron deposition compared to magnetic resonance imaging (MRI) T2* imaging. Thirty-one patients with a clinical history of myelodysplastic syndromes and aplastic anemia underwent liver and cardiac T2*-weighted unenhanced MRI on a three-tesla MRI scanner, and underwent unenhanced CT scan laterally on a 128-row spectral detector CT. R2* values of the liver, septal muscle, and paraspinal muscle were calculated. Attenuation differences (ΔH) in the liver and myocardium were calculated between the lower (50 keV) and higher (120 keV) energy levels. The liver and cardiac T2* values were 9.54 ± 5.63 ms and 21.41 ± 2.44 ms, respectively. The liver-to-muscle and myocardium-to-muscle T2* value ratios were 0.37 ± 0.23 and 0.79 ± 0.19, respectively. The liver and cardiac ΔH were − 1.13 ± 4.24 HU and 2.22 ± 4.41 HU, respectively. There was a strong linear correlation between the liver R2* and ΔH (r = − 0.832, P

Objective The most severe complication associated with giant coronary aneurysm in children with Kawasaki disease is ischemic cardiomyopathy (ICM) caused by thrombolysis. Effective thrombolytic therapy has a significant impact on patients’ quality of life in long term. Methods To describe the effects of alteplase for once + heparin for 1 week/ then continue warfarin + aspirin + clopidogrel oral treatment for KD children with central thrombus in coronary aneurysm. These patients were treated in pediatric cardiology department of Shengjing hospital, China medical university, between 2020 Jan to 2021 August. Results Total 4 boys (7 times) had CAA complicated with central thrombosis. 5 times treatment with alteplase and heparin/ warfarin/ aspirin/ clopidogrel for 10 days to 2 months, all succeed. Conclusion 1. In KD pediatric patients complicated with coronary aneurysm thrombosis, small but convexity lumen thrombus with strong echo less than one month and large thrombus with strong and weak mixed echo, coronary artery blood flow can be improved or completely recovered after the above treatment. 2. Alteplase should not be strictly limited to within 12 hours of thrombosis. 3. Children with KD complicated with coronary aneurysm thrombosis are prone to thrombosis again.

Background and AimPericoronary adipose tissue (PCAT) reflects pericoronary inflammation and is associated with coronary artery disease. We aimed to identify the association between local PCTA thickness using cardiac magnetic resonance (CMR) and prognosis of patients with ST-elevation myocardial infarction (STEMI), and to investigate the incremental prognostic value of PCAT thickness in STEMI after reperfusion.MethodsA total of 245 patients with STEMI (mean age, 55.61 ± 10.52 years) who underwent CMR imaging within 1 week of percutaneous coronary intervention therapy and 35 matched controls (mean age, 53.89 ± 9.45 years) were enrolled. PCAT thickness indexed to body surface area at five locations, ventricular volume and function, infarct-related parameters, and global strain indices were evaluated using CMR. Associations between PCAT thickness index and 1-year major adverse cardiovascular events (MACE) after STEMI were calculated. The prognostic value of the standard model based on features of clinical and CMR and updated model including PACT thickness index were further assessed.ResultsPatients with MACE had a more significant increase in PCAT thickness index at superior interventricular groove (SIVGi) than patients without MACE. The SIVGi was significantly associated with left ventricular ejection fraction (LVEF), infarct size, and global deformation. SIVGi > 4.98 mm/m2 was an independent predictor of MACE (hazard ratio, 3.2; 95% CI: 1.6–6.38; p < 0.001). The updated model significantly improved the power of prediction and had better discrimination ability than that of the standard model for predicting 1-year MACE (areas under the ROC curve [AUC] = 0.8 [95% CI: 0.74–0.87] vs. AUC = 0.76 [95% CI: 0.68–0.83], p < 0.05; category-free net reclassification index [cfNRI] = 0.38 [95% CI: 0.1–0.53, p = 0.01]; integrated discrimination improvement [IDI] = 0.09 [95% CI: 0.01–0.18, p = 0.02]).ConclusionsThis study demonstrated SIVGi as an independent predictor conferred incremental value over standard model based on clinical and CMR factors in 1-year MACE predictions for STEMI.

Background: Pericoronary adipose tissue (PCAT) is considered as a source of inflammatory mediators, leading to the development of coronary atherosclerosis. The study aimed to investigate the correlation between PCAT quality derived from dual-layer spectral detector CT (SDCT) and the severity of coronary artery disease (CAD), and whether PCAT parameters were independently associated with the presence of CAD.Materials and Methods: A total of 403 patients with symptoms of chest pain who underwent SDCT were included. PCAT quality including fat attenuation index (FAI) measured from conventional polychromatic CT images (FAI120kvp) and spectral virtual mono-energetic images at 40 keV (FAI40keV), slope of spectral HU curve (λHU), and effective atomic number (Eff-Z) were measured around the lesions representing the maximal degree of vascular stenosis in each patient. Meanwhile, overall epicardial adipose tissue (EAT) attenuation was acquired in the conventional polychromatic energy imaging.Results: FAI40keV, λHU, Eff-Z, and FAI120kvp increased along with the degree of CAD in general and were superior to the overall EAT attenuation for detecting the presence of CAD. Multivariate logistic regression analysis indicated that FAI40keV was the most powerful independent indicator (odds ratio 1.058, 95% CI 1.044–1.073; p < 0.001) of CAD among these parameters. Using an optimal cut-off (−131.8 HU), FAI40keV showed higher diagnostic accuracy of 80.6% compared with the other parameters.Conclusions: These preliminary findings suggest that FAI40keV on SDCT may be an appealing surrogate maker to allow monitoring of PCAT changes in the development of CAD.

This study was conducted to establish and validate a non-contrast T1 map–based radiomic nomogram for predicting major adverse cardiac events (MACEs) in patients with acute ST-segment elevation myocardial infarction (STEMI) undergoing percutaneous coronary intervention (PCI). This retrospective study included 157 consecutive patients (training sets, 109 patients; test sets, 48 patients) with acute STEMI undergoing PCI. An open-source radiomics software was used to segment the myocardium on the non-contrast T1 mapping and extract features. A radiomic signature was constructed to predict MACEs using the least absolute shrinkage and selection operator method. The performance of the radiomic nomogram for predicting MACEs in both the training and test sets was evaluated by its discrimination, calibration, and clinical usefulness. The radiomic signature showed a good prognostic ability in the training sets with an AUC of 0.94 (95% CI, 0.86 to 1.00) and F1 score of 0.71, which was confirmed in the test sets with an AUC of 0.90 (95% CI, 0.74 to 1.00) and F1 score of 0.62. The nomogram consisting of the radiomic scores and cardiac troponin I showed good discrimination ability in the training and test sets with AUCs of 0.96 (95% CI, 0.91 to 1.00; F1 score, 0.71) and 0.94 (95% CI, 0.83 to 1.00; F1 score, 0.70), respectively. The non-contrast T1 map–based radiomic nomogram is a useful tool for the prediction of MACEs in patients with acute STEMI undergoing PCI that can assist clinicians for optimised risk stratification of individual patients. • Radiomic signature improved MACE prediction in acute STEMI patients. • T1 mapping–derived radiomic signature outperformed conventional cardiac MRI parameters in predicting MACEs in acute STEMI patients. • The non-contrast T1 mapping–based radiomic nomogram can be used for prediction of MACEs and improvement of risk stratification in acute STEMI.

To investigate the potential effect of intracoronary administration of the glycoprotein IIb/IIIa inhibitor tirofiban on the microvascular obstruction (MVO) assessed by cardiac magnetic resonance (CMR) imaging compared to the intravenous route in patients with ST-segment-elevation myocardial infarction undergoing primary percutaneous coronary intervention (PCI). Two hundred eight patients were randomized into two groups (tirofiban i.v. and tirofiban i.c.). CMR was completed within 3–7 days after ST-segment-elevation myocardial infarction. One hundred thirty-two patients had a follow-up CMR at 6 months after discharge. The primary end point was the CMR measurements including myocardium strain, myocardial perfusion index, final infarct size, prevalence and extent of MVO, and the change of left ventricular end-diastolic volume (LVEDV) at six months follow-up. The second endpoint was major adverse cardiovascular events (composite of all-cause death, nonfatal reinfarction and congestive heart failure) in one year. The MVO prevalence and extent [56% versus 36%, p = 0.004; 2.08 (IQR: 1.18–5.07) g versus 1.68 (IQR: 0.30–3.28) g, p = 0.041] showed a significant difference between the intravenous and intracoronary groups. Global left ventricular peak longitudinal strain was significantly different in intracoronary groups compared to intravenous groups, − 12.5 [IQR: − 13.4 to − 10.9] versus − 12.3 [IQR: − 13.4 to − 10.4], respectively (P = 0.042). Infarcted myocardial perfusion index was significantly different in intracoronary groups compared to intravenous groups, 0.11 [IQR: 0.08 to 0.15] versus 0.09 [IQR: 0.07 to 0.14], respectively (P = 0.026). Intracoronary tirofiban was associated with a higher change in LVEDV compared with intravenous group (− 10.2% [IQR: − 13.7% to − 2.6%] versus 1.3% [IQR: − 5.6% to 6.1%], p

OBJECTIVE To evaluate the feasibility of texture analysis on non-contrast-enhanced T1 maps of cardiac magnetic resonance (CMR) imaging for the diagnosis of myocardial injury in acute myocardial infarction (MI). MATERIALS AND METHODS This study included 68 patients (57 males and 11 females; mean age, 55.7 ± 10.5 years) with acute ST-segment-elevation MI who had undergone 3T CMR after a percutaneous coronary intervention. Forty patients of them also underwent a 6-month follow-up CMR. The CMR protocol included T2-weighted imaging, T1 mapping, rest first-pass perfusion, and late gadolinium enhancement. Radiomics features were extracted from the T1 maps using open-source software. Radiomics signatures were constructed with the selected strongest features to evaluate the myocardial injury severity and predict the recovery of left ventricular (LV) longitudinal systolic myocardial contractility. RESULTS A total of 1088 segments of the acute CMR images were analyzed; 103 (9.5%) segments showed microvascular obstruction (MVO), and 557 (51.2%) segments showed MI. A total of 640 segments were included in the 6-month follow-up analysis, of which 160 (25.0%) segments showed favorable recovery of LV longitudinal systolic myocardial contractility. Combined radiomics signature and T1 values resulted in a higher diagnostic performance for MVO compared to T1 values alone (area under the curve [AUC] in the training set; 0.88, 0.72, p = 0.031: AUC in the test set; 0.86, 0.71, p002). Combined radiomics signature and T1 values also provided a higher predictive value for LV longitudinal systolic myocardial contractility recovery compared to T1 values (AUC in the training set; 0.76, 0.55, p < 0.001: AUC in the test set; 0.77, 0.60, p < 0.001). CONCLUSION The combination of radiomics of non-contrast-enhanced T1 mapping and T1 values could provide higher diagnostic accuracy for MVO. Radiomics also provides incremental value in the prediction of LV longitudinal systolic myocardial contractility at six months.

BACKGROUND: Depression is common in patients with myocardial infarction and has been independently associated with adverse outcomes. However, the association between depression and myocardial injury on cardiac magnetic resonance (CMR) in patients with ST-segment elevation myocardial infarction (STEMI) has still not been assessed. AIM: To assess the association between depression and myocardial injury on CMR in patients with STEMI. METHODS: A total of 107 STEMI patients undergoing primary percutaneous coronary intervention (P-PCI) were analyzed in this prospectivecohort study. Each subject completed the Patient Health Questionnaire-9 (PHQ-9) to assess the presence and severity of depressive symptoms. CMR was performed at a median of 3 d after P-PCI for quantifying post-MI myocardial injury. Correlations between depression identified by the PHQ-9 and myocardial injury measured on CMR were assessed. RESULTS: In this study, 19 patients (17.8%) were diagnosed with major depression identified by the PHQ-9 ≥ 10. PHQ-9 was analyzed both as a continuous variable and dichotomous variable. After multivariable adjustment, the proportion of patients with large infarction size was significantly higher in the major depression group (PHQ-9 ≥ 10) (OR: 4.840, 95%CI: 1.122–20.868, P =0.034). When the PHQ-9 was evaluated as a continuous variable, after multivariable adjustment, an increased PHQ-9 score was associated with an increased risk of large infarction size (OR: 1.226, 95%CI: 1.073–1.401, P =0.003). CONCLUSION: In patients with STEMI undergoing PCI, depression was independently associated with a large infarction size.

This study aimed to evaluate the accuracy of sequential whole-body PET/MR image coregistration of cervical lesions.Twenty-five patients with cervical carcinomas underwent fluorine-18 fluorodeoxyglucose PET/MR before radiotherapy. MR-volumes of interest (VOIs), PET-VOIs, and apparent diffusion coefficient (ADC)-VOIs were outlined manually on T2-weighted MR images, PET images, and ADC maps. The difference between the lesion centers on PET and MR was determined by calculating the distance of the respective geometric center of gravity. In addition, the tumor volume contour differences were assessed using the dice similarity coefficient for PET and ADC. Results were analyzed by mean±SD and a two-sample t-test.The mean values of the center of gravity mismatch were relatively higher with lesions between PET and ADC (5.79±1.70 mm) than that between PET and MR-T2 (5.22±1.97 mm; P=0.304). Tumor location overlap difference between MR-T2 and PET images (0.64±0.13) was larger than that between ADC and PET (0.56±0.14; P=0.054). The average differences between the centers of lesions on PET and T2-weighted images were 6.25±1.91, 5.24±2.17, and 4.30±1.30 mm for MR-VOI less than 14, 14-62, and at least 62 ml. The average differences between the center of lesions on PET and ADC were 5.97±1.48, 5.43±1.40, and 5.78±2.75 mm, respectively. Image registration tended to be slightly less accurate in the smaller lesions than in the larger lesions (P0.05). The average overlaps were 0.51±0.13, 0.63±0.10, and 0.76±0.03 between the T2-weighted image and PET, respectively. The average overlaps were 0.44±0.14, 0.58±0.11, and 0.66±0.04 between the ADC and PET, respectively. Larger tumors had a higher degree of overlap compared with small tumors (P0.05).Image coregistration of cervical lesions is usually accurate in sequential whole-body PET/MR. The accuracy of image registration between MR-T2 and PET was larger than that between ADC and PET. Image registration tended to be more accurate in the larger lesions.

Objective Integrated positron emission tomography/magnetic resonance imaging (PET/MRI) scanners provide combined MR-based anatomic and metabolic image information. The aim of this study was to evaluate qualitative and quantitative diagnostic performance of PET/MR with 18 fluoro-2-deoxyglucose ( 18 F-FDG) using a diagnostic MR sequence in patients with abdominal and pelvic tumors, compared to positron emission tomography/computed tomography (PET/CT). Materials and methods Forty five patients underwent a single-injection ( 18 F-FDG), dual-imaging protocol including whole-body PET/CT and subsequent regional PET/MR hybrid imaging. A regional PET/MR scan followed the PET/CT. Images from both modalities were analyzed using a 3-point scale for PET/CT and PET/MR image quality, image alignment, and lesion visibility on PET images. PET-CT/PET-MR functional and anatomical correlation was analyzed. Results A total of 66 lesions were studied, from which 63 were identified using PET/CT and 59 were identified using PET/MR. The 18 F-FDG PET images had good diagnostic quality ( P P = 0.102), and there was no difference in lesion visibility ( P = 0.18). The average rating score regarding anatomical correlation for PET-positive lesions was 2.75 for combined MR sequence images and 2.04 for CT, with a significant difference ( P = 0.317), Standard uptake value (SUV) for focal lesions had excellent correlation (SUV max/mean : R = 0.948/0.948); furthermore, the SUV mean of background organs combined, bone marrow and the muscle tissue showed good correlation ( R = 0.329/0.398/0.298). No correlations were found in the liver and spleen. Conclusions PET/MR with diagnostic MR sequence was able to detect abdominal and pelvic lesions and had good image quality compared to PET/CT. SUV max and SUV mean values in focal lesions, and the SUV mean of background organs generally correlated well in abdominal and pelvic oncology patients examined using PET/CT and PET/MRI.

AIM To explore the value of the applying the apparent diffusion coefficient (ADC) to the quantitative diagnosis of temporal bone cholesteatoma. MATERIALS AND METHODS Seventy-one patients clinically suspected of temporal bone cholesteatoma were enrolled prospectively. These patients underwent ear magnetic resonance imaging (MRI) and turbo spin-echo diffusion-weighted imaging (TSE-DWI) using a Philips Ingenia 3 T superconductive MRI system, and their ADCs were measured. Subsequently, all enrolled patients underwent surgery within 15 days of the MRI. Using receiver operating characteristic (ROC) curve analysis, the optimal threshold and diagnostic performance for diagnosing temporal bone cholesteatoma were determined. Logistic regression modelling was used to combine ADCs and T1-weighted imaging (T1WI) sequences and calculate the combined diagnostic performance. RESULTS Based on the pathology results, patients were categorised into the cholesteatoma group (CS group, n=43) and the non-cholesteatoma group (NCS group, n=28). In the CS group, ADCs were significantly lower (mean, 0.87±0.31×10−3 mm2/s) than in the NCS group (mean, 1.87±0.49×10−3 mm2/s; p CONCLUSION ADC quantitative analysis has a high value in the preoperative diagnosis of cholesteatoma, and the combination of ADC and T1WI sequences can improve the diagnostic accuracy and specificity and thereby facilitate clinically effective diagnosis.

To assess the accuracy of compressed SENSE (CS-SENSE) cine cardiac magnetic resonance imaging (CMR) with and without breath-hold in comparison to standard cine CMR with breath-hold for the assessment of left ventricular (LV) function.Thirty-three healthy volunteers underwent balanced turbo field-echo cine CMR with breath-hold (BTFE-BH; reference standard), single breath-hold CS-SENSE (csBTFE-BH) cine CMR, and free-breathing (FB) CS-SENSE (csBTFE-FB) cine CMR on a 3 T MRI system. All images were acquired in stacks of eight short-axis sections. Image quality was assessed and compared by the Wilcoxon matched-pairs signed-rank test. End-diastolic volume, end-systolic volume, stroke volume, ejection fraction, LV end-diastolic (LVED) mass, regional myocardial wall motion, and scan time were compared by paired t-test, linear regression, and Bland-Altman analyses.All techniques provided acceptable image quality (score ≥3) for LV volumetric analysis in all participants (BTFE-BH [reference standard]: 5.00±0.00; csBTFE-BH: 4.03±0.17 [p0.001]; csBTFE-FB: 3.76±0.44 [p0.001]), with good agreement in LV function assessment; however, there was a slight but significant underestimation of LVED mass by csBTFE-FB (csBTFE-FB: 73.63±17.31 g versus BTFE-BH [reference standard]: 75.12±18.18 g, p=0.037). All methods showed a strong correlation with quantitative regional myocardial wall motion. Acquisition times for both csBTFE-BH and csBTFE-FB were significantly shorter than that for BTFE-BH (BTFE-BH [reference standard]: 89.3±5.70 seconds; csBTFE-BH: 24.42±2.18 seconds [p0.001]; csBTFE-FB: 22.48±1.85 seconds [p0.001]).LV function assessment with the novel CS-SENSE cine CMR is not inferior to standard cine CMR, irrespective of BH; however, LVED mass is underestimated by csBTFE-FB.

Objective To clarify the usefulness of 18 F-FDG PET/CT for detecting primary gastric cancer via gastric distention using a mixture of milk and Diatrizoate Meglumine. Materials and methods A total of 68 patients (male: 47, female: 21; age: 41–87 years) suspected of gastric carcinoma underwent 18 F-FDG PET/CT imaging. After whole-body PET/CT imaging in a fasting state, the patients drank a measured amount of milk with Diatrizoate Meglumine. Local gastric district PET/CT imaging was performed 30 min later. The imaging was analyzed by semi-quantitative analysis, standardized uptake value (SUV) of the primary tumor was measured in a region of interest. The diagnosis results were confirmed by gastroscopy, pathology, and follow-up results. Results Of the 68 patients, 56 malignant gastric neoplasm patients (male: 37, female: 19) were conformed. The sensitivity, specificity, positive predictive value and negative predictive value of fasting whole-body PET/CT imaging for a primary malignant tumor were 92.9%, 75.0%, 94.5%, and 69.0%, respectively. The values for distension with a mixture of milk and Diatrizoate Meglumine were 91.1%, 91.7%, 98.1%, and 68.8%, respectively. The area under the curve was 0.919 ± 0.033 and 0.883 ± 0.066 for the diagnosis of gastric cancer with SUV max in a fasting state and after intake of mixture respectively, the differences were not statistically significant ( P = 0.359). Using gastric distension with a mixture of milk and Diatrizoate Meglumine, the mean ratio of the lesion's SUV max to the adjacent gastric wall SUV max increased significantly from 3.30 ± 3.05 to 13.50 ± 15.05, which was statistically significant ( P Conclusions 18 F-FDG PET/CT imaging is highly accurate for the diagnosis of primary gastric carcinoma. Gastric distention can display the lesions more clearly, however, it cannot significantly improve diagnostic accuracy.

The aim of the study was to determine the standardized uptake value (SUV) threshold on gross tumor volume from PET images (PET-GTV) that generates the maximal spatial overlap with MRI-defined GTV (MR-GTV) in locally advanced cervical cancer with the aid of hybrid PET/MRI.Twenty-seven patients with cervical carcinomas underwent F-FDG PET/MRI before radiotherapy. MR-GTV was manually outlined on T2-weighted MRI. PET-GTVs were contoured on PET images using visual inspection (PETvis-GTV), 2.5 SUV (PET2.5-GTV) and 40% SUVmax threshold (PET40-GTV), and compared with MR-GTV. All PET data were reviewed again. The PET-GTV was determined, with the SUVmax threshold defined as the value at which the Dice similarity coefficient (DSC) between PET-GTV and MR-GTV was maximal (PETdsc-GTV). Results were analyzed by Pearson's analysis, the t-test, and one-way analysis of variance.The mean PETvis-GTV, PET40-GTV, and PET2.5-GTV were significantly different from the mean MR-GTV. The average DSCs were 0.64, 0.65, and 0.68 for PETvis-GTV, PET40-GTV, and PET2.5-GTV with MR-GTV, respectively. The mean threshold of PETdsc-GTV was 29.4% SUVmax, with a maximal DSC value of 0.72 in all patients. PET-GTVs as defined by thresholds of 25 and 30% of SUVmax were not statistically different from the MR-GTV. The mean thresholds of PETdsc-GTV were 43.3±8.8, 27.9±5.8, and 22.2±2.6% for MR-GTV14, 14-62, and ≥62 cm, respectively.PETvis-GTV, PET2.5-GTV, and PET40-GTV do not appear to be suitable for target volume delineation in locally advanced cervical cancer. The PETdsc-GTV may increase the accuracy in target volume delineation. Furthermore, a high level of tumor overlap existed between MR-GTV and PETdsc-GTV in hybrid PET/MRI.

ObjectiveThis study aimed to compare the tumor volume between magnetic resonance imaging–defined gross tumor volume (MR-GTV) and positron emission tomography–defined GTV (PET-GTV) in cervical cancer with hybrid PET/MR.Materials and MethodsTwenty-seven patients with cervical cancer underwent PET/MR pelvic examination before radiotherapy. The MR-GTV was manually outlined on T2-weighted MR images. The PET-GTV was autocontoured on PET images using a 40% maximum standardized uptake value threshold. Results were analyzed by Pearson analysis, Bland-Altman plot, and 1-way analysis of variance.ResultsMagnetic resonance imaging–GTV significantly correlated with PET-GTV (r2 = 0.797, P < 0.001). The Bland-Altman plot showed a bad agreement between MR-GTV and PET-GTV. The PET-GTV underestimated the MR-GTV in 23 of 27 tumors. Patients were divided into the following 3 groups according to MR-GTV: less than 14 mL (n = 6), 14 to 62 mL (n = 12), and 62 mL or more (n = 9). The mean (SD) MR-GTV, PET-GTV, ratio, and overlap between MR-GTV and PET-GTV for the less than 14 mL cohort were 9.6 (2.6) mL, 16.7 (10.1) mL, 0.77 (0.40), and 0.47 (0.20), respectively. The PET-GTV overestimated MR-GTV in 4 of the 6 lesions by a mean (SD) of 11.1 (9.4) mL. Among the 14 to 62 mL cohort, the mean (SD) MR-GTV, PET-GTV, ratio, and overlap were 38.6 (14.5) mL, 24.9 (8.6 mL), 1.54 (0.25), and 0.87 (0.08), respectively. The PET-GTV underestimated MR-GTV for 12 tumors by a mean (SD) of 13.7 (8.4) mL. In the 62 mL or more cohort, the mean (SD) MR-GTV, PET-GTV, ratio, and overlap were 85.9 (25.8) mL, 54.3 (14.1) mL, 1.61 (0.35), and 0.87 (0.09), respectively. The PET-GTV underestimated MR-GTV 9 tumors by a mean (SD) of 31.6 (19.5) mL. The ratio and overlap differences were statistically significant among groups (F = 14.619, P < 0.001; F = 25.134, P < 0.001).ConclusionsTumor volume discrepancies were observed between MR-GTV and PET-GTV for cervical cancer. With an increasing tumor volume, there was an increase in the difference between MR-GTV and PET-GTV. In addition, larger tumors had a higher degree of overlap compared with small tumors.

To clarify the usefulness of (18)F-FDG PET/CT for detecting primary gastric cancer via gastric distention using a mixture of milk and Diatrizoate Meglumine.A total of 68 patients (male: 47, female: 21; age: 41-87 years) suspected of gastric carcinoma underwent (18)F-FDG PET/CT imaging. After whole-body PET/CT imaging in a fasting state, the patients drank a measured amount of milk with Diatrizoate Meglumine. Local gastric district PET/CT imaging was performed 30 min later. The imaging was analyzed by semi-quantitative analysis, standardized uptake value (SUV) of the primary tumor was measured in a region of interest. The diagnosis results were confirmed by gastroscopy, pathology, and follow-up results.Of the 68 patients, 56 malignant gastric neoplasm patients (male: 37, female: 19) were conformed. The sensitivity, specificity, positive predictive value and negative predictive value of fasting whole-body PET/CT imaging for a primary malignant tumor were 92.9%, 75.0%, 94.5%, and 69.0%, respectively. The values for distension with a mixture of milk and Diatrizoate Meglumine were 91.1%, 91.7%, 98.1%, and 68.8%, respectively. The area under the curve was 0.919 ± 0.033 and 0.883 ± 0.066 for the diagnosis of gastric cancer with SUVmax in a fasting state and after intake of mixture respectively, the differences were not statistically significant (P=0.359). Using gastric distension with a mixture of milk and Diatrizoate Meglumine, the mean ratio of the lesion's SUVmax to the adjacent gastric wall SUVmax increased significantly from 3.30 ± 3.05 to 13.50 ± 15.05, which was statistically significant (P0.001).(18)F-FDG PET/CT imaging is highly accurate for the diagnosis of primary gastric carcinoma. Gastric distention can display the lesions more clearly, however, it cannot significantly improve diagnostic accuracy.