MRI-based radiomics feature combined with tumor markers to predict TN staging of rectal cancer.

The aim of this study is to evaluate the predictive ability of MRI-based radiomics combined with tumor markers for TN staging in patients with rectal cancer and to develop a prediction model for TN staging. A total of 190 patients with rectal adenocarcinoma who underwent total mesorectal excision at the First Affiliated Hospital of the Air Force Medical University between January 2016 and December 2020 were included in the study. An additional 54 patients from a prospective validation cohort were included between August 2022 and August 2023. Preoperative tumor markers and MRI imaging data were collected from all enrolled patients. The 190 patients were divided into a training cohort (n = 133) and a validation cohort (n = 57). Radiomics features were extracted by outlining the region of interest (ROI) on T2WI sequence images. Feature selection and radiomics score (Rad-score) construction were performed using least absolute shrinkage and selection operator regression analysis (LASSO). The postoperative pathology TNM stage was used to differentiate locally advanced rectal cancer (T3/4 or N1/2) from locally early rectal cancer (T1/2, N0). Logistic regression was used to construct separate prediction models for T stage and N stage. The models' predictive performance was evaluated using DCA curves and calibration curves. The T staging model showed that Rad-score, based on 8 radiomics features, was an independent predictor of T staging. When combined with CEA, tumor diameter, mesoretal fascia (MRF), and extramural venous invasion (EMVI), it effectively differentiated between T1/2 and T3/4 stage rectal cancers in the training cohort (AUC 0.87 [95% CI: 0.81-0.93]). The N-staging model found that Rad-score, based on 10 radiomics features, was an independent predictor of N-staging. When combined with CA19.9, degree of differentiation, and EMVI, it effectively differentiated between N0 and N1/2 stage rectal cancers. The training cohort had an AUC of 0.84 (95% CI: 0.77-0.91). The calibration curves demonstrated good precision between the predicted and actual results. The DCA curves indicated that both sets of predictive models could provide net clinical benefits for diagnosis. MRI-based radiomics features are independent predictors of T staging and N staging. When combined with tumor markers, they have good predictive efficacy for TN staging of rectal cancer.

Neurological prognosis in surgically treated acute aortic dissection with brain computed tomography perfusion.

OBJECTIVES: The aim of this study was to explore the prognostic value of brain computed tomography perfusion (CTP) for postoperative new stroke in acute type A aortic dissection (ATAAD) patients. METHODS: Patients with ATAAD and suspected cerebral malperfusion who underwent brain CTP and surgical repair were retrospectively analysed. Brain perfusion was quantified mainly with the averaged cerebral blood flow. Significant clinical and imaging findings were identified through univariable and multivariable regression analysis. Furthermore, the added prognostic benefit of perfusion parameters was confirmed with the receiver operating characteristic curves in the entire cohort and subgroup analysis. RESULTS: The incidence of postoperative new stroke was 30.8% (44/143). The independent adjusted predictors of postoperative new stroke included an impaired averaged cerebral blood flow (ml/100 ml/min) (odds ratio: 0.889; P < 0.001), severe stenosis (odds ratio: 5.218; P = 0.011) or occlusion (odds ratio: 14.697; P = 0.048) of the true lumen in common carotid artery (CCA), hypotension on admission (odds ratio: 9.644; P = 0.016) and a longer surgery time (odds ratio: 1.593; P = 0.021). The area under the receiver operating characteristic curves significantly improved after adding perfusion parameters to clinical and computed tomography angiography characteristics (P = 0.048). This benefit was more pronounced in patients with severe stenosis or occlusion in CCA true lumen (P = 0.004). CONCLUSIONS: Brain CTP could be a useful prognostic tool for surgically treated ATAAD patients and especially beneficial in patients with severe stenosis or occlusion of the CCA true lumen.

Association of Objective Sleep Characteristics and Incident Angina Pectoris: A Longitudinal Analysis from the Sleep Heart Health Study.

Purpose: While prior research has highlighted a significant association between sleep characteristics and angina pectoris (AP) incidence, the link between sleep efficiency (SE) and angina remains unexplored. This study seeks to elucidate the relationship between AP and objectively quantified SE. Patients and Methods: We examined a cohort of 2990 participants (1320 males and 1670 females; mean age 63.69 ± 13.2 years) from the Sleep Heart Health Study. The main exposure variable was SE, as determined by baseline home polysomnography, while the primary outcome was the first incidence of angina pectoris (AP) during the period between the baseline polysomnography and the end of follow-up. A multivariate Cox regression model was utilized, controlling for factors such as age, gender, BMI, smoking and alcohol consumption habits, diabetes, hypertension, sleep duration, triglycerides, cholesterol, high-density lipoprotein, apnea-hypopnea index, nocturnal oxygen saturation, to analyze the relationship between SE and AP. Results: During an average follow-up of 11 years, 284 patients developed AP. The unadjusted Kaplan-Meier analysis identified the 2nd quartile of SE as having the lowest AP risk. The multivariate Cox proportional hazards model demonstrated a higher risk of AP in quartile 1 (HR, 1.679; 95% CI, 1.109-2.542; P <0.014) and quartile 3 (HR, 1.503; 95% CI, 1.037-2.179; P <0.031), compared to quartile 2 of SE. Upon stratified analysis, this relationship was particularly pronounced in hypertensive individuals. Conclusion: Our results highlight the critical role of optimal sleep efficiency in mitigating the risk of angina pectoris, especially among hypertensive individuals.

Predictive Value of CT-Based Radiomics in Distinguishing Renal Angiomyolipomas with Minimal Fat from Other Renal Tumors.

Objectives: This study is aimed at determining whether CT-based radiomics models can help differentiate renal angiomyolipomas with minimal fat (AMLmf) from other solid renal tumors. Methods: This retrospective study included 58 patients with a postoperative pathologically confirmed AMLmf (observation group) and 140 patients with other common renal tumors (control group). Non-contrast-enhanced CT and contrast-enhanced CT data were evaluated. Radiomics features were extracted from manually delineated volume of interest (VOIs). The least absolute shrinkage and selection operator (LASSO) regression was used for feature screening. Five classifiers, including logistic regression, multilayer perceptron (MLP), support vector machine (SVM), k-nearest neighbor (KNN), and logistic regression (LR), were used, with leave-out validation (128 training, 60 testing). The diagnostic performance of the classifier was evaluated and compared by receiver operating characteristic curve (ROC) analysis. Results: Among the 1029 extracted features, prediction models of AMLmf were composed, by 2, 10, 4, and 9 selected features for precontrast phase (PCP), corticomedullary phase (CMP), nephrographic phase (NP), and excretory phase (EP), respectively. Models of CMP and NP achieved adequate performance after using MLP classifier, with prediction accuracy of 0.767 (AUC 0.85, sensitivity 0.76, and specificity 0.78) and 0.783 (AUC 0.83, sensitivity 0.79, and specificity 0.78), respectively. MLP model of features selected from the combination of the all features had the best diagnostic performance (accuracy 0.8500, sensitivity 0.8095, specificity 0.9444, and AUC 0.9193). Conclusions: Radiomics features may help to distinguish benign AMLmf from common malignant kidney masses, which may contribute to the selection of interventions for renal tumors.

Improved interobserver agreement on nodule type and Lung-RADS classification of subsolid nodules using computer-aided solid component measurement.

PURPOSE: The Lung CT Screening Reporting and Data System (Lung-RADS) classification of subsolid nodules (SSNs) can be challenging due to limited interobserver agreement in determining the type and size of the nodule. Our study aimed to assess the effect of a computer-aided method on the interobserver agreement of Lung-RADS classification for SSNs. MATERIALS AND METHODS: This study consisted of 156 SSNs in 121 patients who underwent initial CT screening for lung cancer. Three independent readers determined the nodule type and measured the size of the entire nodule as well as the solid component, first without and then assisted by a semi-automated computer-aided tool. They assigned to each nodule the corresponding Lung-RADS 1.1 category. Agreement in size measurements was assessed by intraclass correlation coefficient (ICC) and Bland-Altman indexes, while agreement in nodule type and Lung-RADS was determined using Fleiss kappa statistics. The relationship between final diagnosis of the nodules and Lung-RADS classifications was also evaluated. RESULTS: Among the 156 nodules, manual size measurement reached an ICC of 0.994, and 48 nodules contained solid component measured by all the three readers both manually and semi-automatically. ICCs for the solid component measurement were 0.952, 0.997 and 0.996 for manual diameter, semi- automated diameter and volume measurement, respectively. Bias and 95% limits of agreement for average diameter of solid component were smaller with semi-automated measurements than with manual measurements. Kappa values of semi-automated assessment for nodule type (0.974) and Lung-RADS classification (0.958 for diameter and 0.952 for volume) were higher than with the manual measurements (0.783 for nodule type and 0.652 for Lung-RADS classification). Compared to manual work, the semi-automated assessment identified more 4B nodules among the 26 pathologically confirmed invasive adenocarcinomas (IACs). CONCLUSION: Semi-automated assessment could improve the interobserver agreement of nodule type and Lung-RADS classification for SSNs, and be inclined to classify SSNs corresponding to pathologically confirmed IACs into higher risk categories.

Role of contrast-enhanced ultrasonography in MR-guided focused ultrasound ablation on uterus fibroids: lesion selection and assessment of ablative effects.

OBJECTIVES: To determine whether contrast-enhanced ultrasonography (CEUS) can be used for selecting lesions and assessing the ablative effects of MRgFUS ablation on uterus fibroids, compared with MR imaging. METHODS: This retrospective study was approved by the institutional review board of our hospital. From April 2018 to November 2019, a total of 44 symptomatic fibroids in 38 patients who underwent MRgFUS ablation were included. The association between pre-ablation characteristics on CEUS/MR imaging and the non-perfusion volume (NPV) after ablation was analyzed using multivariable linear regression analysis. The area under the curve (AUC) of the receiver operating characteristic (ROC) curve values was compared between the CEUS and MR imaging regression models. NPV after ablation was compared between CEUS and enhanced MR imaging. RESULTS: On CEUS, entangled branch vessels, fast-in, and fast-out patterns were significantly associated with NPV, with an AUC of 0.95 (95% CI; 0.88, 1.00). On MR imaging, hyper-intensity on T2-weighted images (T2WI), hyper-intense ring-like signal on T2WI images, and hyper-enhancement on contrast-enhanced T1WI images were correlated with NPV, with an AUC of 0.86 (95% CI; 0.70, 1.00). After ablation, no differences in NPV were noted between contrast-enhanced T1WI (84.13 ± 75.42 cm3) and CEUS (80.22 ± 76.49 cm3). CONCLUSIONS: Some pre-ablation characteristics of uterine fibroids on CEUS were associated with NPV after MRgFUS. CEUS may contribute to the evaluation of ablative outcomes and patient selection, similar to MR imaging. KEY POINTS: • Contrast-enhanced ultrasonography (CEUS) is effective for selecting the appropriate uterine fibroids before MR-guided focused ultrasound (MRgFUS) ablation and evaluating non-perfusion volumes (NPV) after ablation, as a potential alternative to MR imaging. • Before ablation, entangled branch vessels, fast-in, and fast-out patterns on CEUS were significantly associated with NPV after MRgFUS. • No significant differences in NPV were detected between contrast-enhanced T1WI and CEUS after ablation.

The Clinical and MRI Effect of TNF-α Inhibitors in Spondyloarthritis Patients With Hip Involvement: A Real-World Observational Clinical Study.

Objectives: Hip involvement is an important cause of disability and poor prognosis in patients with spondyloarthritis (SpA). Tumor necrosis factor (TNF)-α inhibitor treatment has been demonstrated to be effective in SpA patients with hip arthritis; however, quantitative assessment using MRI in long-term follow-up needs further application and observation. Methods: A total of 239 patients were involved in this study. Methotrexate and sulfasalazine were given as basic treatment. In total, 165 patients received TNF-α inhibitors plus basic treatment, and 74 received basic treatment only, as controls. Clinical symptoms were assessed at baseline and at weeks 12, 24, and 52. MRI performances of hip arthritis, including bone marrow edema (BME) and synovitis, were quantitatively assessed using the Hip Inflammation MRI Scoring System (HIMRISS). Results: The clinical values of erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), Bath Ankylosing Spondylitis Disease Activity Index (BASDAI), Harris hip score, and Ankylosing Spondylitis Disease Activity Score (ASDAS)-ESR in both groups showed significant clinical remission at week 52 (p < 0.001). However, the change in disease activity levels at week 52 in the control group was significantly worse than in the TNF-α inhibitor group. At week 52, MRI showed a significant remission trend in the TNF-α inhibitor group versus baseline, and total HIMRISS scores were significantly decreased (26.49 ± 10.37 vs. 20.59 ± 9.41, p < 0.001); the control group only had slight improvement (p < 0.05). Conclusions: TNF-α inhibitors could significantly improve clinical and MRI manifestations of hip involvement in patients with SpA. Quantitative MRI assessment combined with clinical assessment can be used to accurately evaluate the treatment effect of TNF-α in SpA patients with hip involvement to help guide targeted treatment.

Predicting Disease-Free Survival With Multiparametric MRI-Derived Radiomic Signature in Cervical Cancer Patients Underwent CCRT.

Prognostic biomarkers that can reliably predict the disease-free survival (DFS) of locally advanced cervical cancer (LACC) are needed for identifying those patients at high risk for progression, who may benefit from a more aggressive treatment. In the present study, we aimed to construct a multiparametric MRI-derived radiomic signature for predicting DFS of LACC patients who underwent concurrent chemoradiotherapy (CCRT). METHODS: This multicenter retrospective study recruited 263 patients with International Federation of Gynecology and Obetrics (FIGO) stage IB-IVA treated with CCRT for whom pretreatment MRI scans were performed. They were randomly divided into two groups: primary cohort (n = 178) and validation cohort (n = 85). The LASSO regression and Cox proportional hazard regression were conducted to construct the radiomic signature (RS). According to the cutoff of the RS value, patients were dichotomized into low- and high-risk groups. Pearson's correlation and Kaplan-Meier analysis were conducted to evaluate the association between the RS and DFS. The RS, the clinical model incorporating FIGO stage and lymph node metastasis by the multivariate Cox proportional hazard model, and a combined model incorporating RS and clinical model were constructed to estimate DFS individually. RESULTS: The final radiomic signature consisted of four radiomic features: T2W_wavelet-LH_ glszm_Size Zone NonUniformity, ADC_wavelet-HL-first order_ Median, ADC_wavelet-HH-glrlm_Long Run Low Gray Level Emphasis, and ADC_wavelet _LL_gldm_Large Dependence High Gray Emphasis. Higher RS was significantly associated with worse DFS in the primary and validation cohorts (both p<0.001). The RS demonstrated better prognostic performance in predicting DFS than the clinical model in both cohorts (C-index, 0.736-0.758 for RS, and 0.603-0.649 for clinical model). However, the combined model showed no significant improvement (C-index, 0.648, 95% CI, 0.571-0.685). CONCLUSIONS: The present study indicated that the multiparametric MRI-derived radiomic signature could be used as a non-invasive prognostic tool for predicting DFS in LACC patients.

DCE-MRI Quantitative Parameters as Predictors of Treatment Response in Patients With Locally Advanced Cervical Squamous Cell Carcinoma Underwent CCRT.

PURPOSE: To evaluate the predictive value of dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) quantitative parameters in treatment response to concurrent chemoradiotherapy (CCRT) for locally advanced cervical squamous cell carcinoma (LACSC). METHODS AND MATERIALS: LACSC patients underwent CCRT had DCE-MRI before (e0) and after 3 days of treatment (e3). Extended Tofts Linear model with a user arterial input function was adopted to generate quantitative measurements. Endothelial transfer constant (Ktrans), reflux rate (Kep), fractional extravascular extracellular space volume (Ve), and fractional plasma volume (Vp) were calculated, and percentage changes ΔKtrans, ΔKep, ΔVe, and ΔVp were computed. The correlations of these measurements with the tumor regression rate were analyzed. The predictive value of these parameters on treatment outcome was generated by the receiver operating characteristic (ROC) curve. Univariate and multivariate logistic regression analyses were conducted to find the independent variables. RESULTS: Ktrans-e0, Kep -e0, ΔKtrans, and ΔVe were positively correlated with the tumor regression rate. Mean values of Ktrans-e0, Ktrans-e3, ΔKtrans, and ΔVe were higher in the non-residual tumor group than residual tumor group and were independent prognostic factors for predicting residual tumor occurrence. Ktrans-e3 showed the highest area under the curve (AUC) for treatment response prediction. CONCLUSIONS: Quantitative parameters at e0 and e3 from DCE-MRI could be used as potential indicators for predicting treatment response of LACSC.

Computed tomography angiography findings predict the risk factors for preoperative acute ischaemic stroke in patients with acute type A aortic dissection.

OBJECTIVES: Acute ischaemic stroke (AIS) is a highly dreaded complication of acute type A aortic dissection (ATAAD). Knowledge about independent predictors of preoperative AIS in patients with ATAAD remains unclear. The aim of this study was to identify the risk factors for preoperative AIS in patients with ATAAD by computed tomography angiography (CTA) findings. METHODS: Between October 2014 and March 2017, 281 (217 male; mean age, 50 years) patients with ATAAD underwent aortic CTA and diffusion-weighted magnetic resonance imaging of the brain was used to confirm the results. The clinical data and CTA findings were evaluated retrospectively. Patients were divided into 2 groups depending on the presence or absence of preoperative AIS. RESULTS: Preoperative AIS was detected in 103 (36.7%) of the patients with ATAAD. Univariable analysis of the clinical characteristics and CTA findings revealed that age, aortic valve insufficiency (moderate or severe), the ratio of the diameter of the true lumen of the ascending aorta to the diameter of the involved ascending aorta, intimal flap plaque, dissection of the common carotid artery (CCA), the lower density of the unilateral internal carotid artery, the CCA originating from the false lumen and dissection of the subclavian artery were implicated in patients with ATAAD with AIS. Multivariable analysis further showed that aortic valve insufficiency (moderate or severe) [odds ratio (OR) 2.033, 95% confidence interval (CI) 1.052-3.931; P = 0.035], 2 CTA findings including the ratio of the diameters (OR 0.074, 95% CI 0.011-0.516; P = 0.009) and dissection of the CCA (OR 2.422, 95% CI 1.389-4.224; P = 0.002) were independent risk predictors for preoperative AIS in patients with ATAAD. The lower density in the false lumen, the same enhancement in the true and false lumen with re-entry and the stenosis of the true lumen without re-entry significantly increased the risk of preoperative AIS in CCA dissection. CONCLUSIONS: Aortic valve insufficiency (moderate or severe), the ratio of the diameters of the true and false lumens and CCA dissection are independent predictors of preoperative AIS in patients with ATAAD. The specific carotid and aortic CTA findings may help to predict the risk factors for preoperative AIS in patients with ATAAD. CLINICAL REGISTRATION NUMBER: 20120216-4.

Combined CT angiography of the aorta and craniocervical artery: a new imaging protocol for assessment of acute type A aortic dissection.

BACKGROUND: To investigate the feasibility of combined computed tomography angiography (CTA) of the aorta and craniocervical artery in acute type A aortic dissection (ATAAD) and the value of incremental craniocervical information. METHODS: Combined CTA of head, neck and aorta was performed in patients with suspected aortic dissection and 243 ATAAD patients were analyzed. The image quality and radiation dose were assessed. Valuable craniocervical CTA findings were determined for further surgical analysis. RESULTS: The mean dose-length product (DLP) was 314.11±29.31 mGy.cm. The image quality of craniocervical arteries were 100% diagnostic. Intimal flap involving carotid arteries was detected in 47% of patients, and significant stenosis of true lumen was observed in 60% of common carotid arteries (CCAs). Hypodensity and hypoplasia/occlusion of carotid arteries were also detected and apprised surgeons. The tortuosity of carotid artery was found in 90.9% of patients. Bilateral antegrade selective cerebral perfusion (ASCP) was performed in 21.1% of aortic arch surgery based on 7 hemodynamic variation types of the circle of Willis (CW) determined by cranial CTA information. CONCLUSIONS: A combined CTA of head, neck and aorta is feasible with low radiation dose and diagnostic image quality. Incremental information on craniocervical pathology and anatomy may be useful for surgery repair of ATAAD.

Computed Tomographic Angiography-Based Characterization of Source Blood Vessels for Nipple-Areola Complex Perfusion in Hypertrophic Breasts.

BACKGROUND: Current knowledge about the blood supply of the nipple-areola complex (NAC) has largely been derived from studies on cadavers or persons with breasts of normal size. The aim of this study was to identify and classify the NAC blood supply by computed tomographic angiography (CTA) examination in female volunteers with breast hypertrophy. METHODS: CTA examination was performed on hypertrophic breasts of 23 female subjects. The main blood supplies were revealed through image data analyses. The dominant blood supply of the NAC and its vascular sources were identified and sorted. The detectable diameter threshold of blood vessels was set beyond 1.0 mm. RESULTS: A total of 61 dominant blood vessels were identified. The source arteries were traced as the internal thoracic artery (ITA, 50.8%), lateral thoracic artery (LTA, 27.8%), thoracoacromial artery (TA, 14.8%), brachial artery (BA, 3.3%), and axillary artery (AA, 3.3%), and the corresponding reproducibility of these source vessels was 31, 37, 9, 4.3, and 4.3%, in all breasts. The intercostal artery (IA) was not identified as a dominant NAC supplying vessel in any CTA scan image. Twenty-six breasts had only one dominant artery, whereas 17 breasts showed multiple dominant blood supplies. Three breasts showed no dominant blood vessels of the NAC, with diameters greater than the detectable threshold of 1.0 mm, and 52.2% of the breasts demonstrated anatomically symmetrical patterns of blood supply for the NAC. CONCLUSIONS: The ITA, LTA, and TA are likely to be the main vessel sources, whereas the IA is unlikely to be the dominant vessel for NAC perfusion, on the basis of the studied breasts. An asymmetrical pattern of bilateral breast blood supply was demonstrated in a considerable portion of the females with breast hypertrophy in this study. LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Image quality and radiation dose of dual-source CT cardiac angiography using prospective ECG-triggering technique in pediatric patients with congenital heart disease.

BACKGROUND: All studies involving use of ionizing radiation should be performed in accordance with the ALARA (As Low As Reasonably Achievable) principle, especially in children. In this study, the prospective ECG triggering technique with low voltage was used in dual-source computed tomography (DSCT) angiography to investigate if image quality with low radiation dose could be satisfactory in pediatric patients with congenital heart disease. METHODS: Sixty pediatric patients with suspected congenital cardiovascular anomalies were enrolled prospectively in the study. They were randomly assigned to two groups for DSCT angiography. Group A were scanned by prospective ECG-triggering computed tomography angiography (CTA) with 80 kV tube voltage, while group B by used non-ECG-gated CTA with the same tube voltage. The anomaly accuracy was evaluated based on the surgical and/or conventional cardiac angiography findings. The overall image quality was assessed on a five-point scale. And the diagnostic accuracy and radiation dose was evaluated in both groups. RESULTS: There were 127 cardiovascular anomalies in Group A and 108 in Group B. The mean subjective image quality and diagnostic accuracy between these two groups were significantly different (P = 0.007 and 0.011, respectively). The mean effective dose in Group A and Group B was 0.38 ± 0.13 mSv and 0.35 ± 0.17 mSv, respectively. But there was no significant difference between two groups (P = 0.197). CONCLUSIONS: The prospective ECG triggering technique in DSCT scan can offer better image quality and diagnostic accuracy with low radiation exposure in pediatric patients with congenital heart diseases. This technique has potential to become a new clinical routine in pediatric cardiac computed tomography (CT) imaging.

Primary mediastinal giant liposarcoma with smooth muscle and neural differentiation: A case report.

Liposarcoma has previously been described in Western studies, however, such cases are rarely reported in the mediastinum. In addition, the presence of a liposarcoma with smooth muscle and neural differentiation has not been previously reported. Thus, the present study describes the rare case of a 28-year-old Chinese male admitted to our hospital with the symptoms of chest tightness and shortness of breath due to a recurrent fibrolipoma in the mediastinum. The resected tumor measured 23 cm at its largest diameter, with histopathological and immunohistochemical features indicating a well-differentiated liposarcoma accompanied by smooth muscle and neural differentiation. Following the resection, the patient underwent radiation treatment and remains alive with no evidence of disease recurrence at two months post-surgery. To the best of our knowledge, the present study is the first to report a case of liposarcoma with smooth muscle and neural differentiation, which indicates that liposarcomas could potentially originate from stem cells. The present study highlights the fact that pathologists must carefully investigate the histopathological characteristics of liposarcomas in order to obtain an accurate diagnosis.

Effect of reduced x-ray tube voltage, low iodine concentration contrast medium, and sinogram-affirmed iterative reconstruction on image quality and radiation dose at coronary CT angiography: results of the prospective multicenter REALISE trial.

BACKGROUND: Both low tube voltage and sinogram-affirmed iterative reconstruction (IR) techniques hold promise to decrease radiation dose at coronary CT angiography (CCTA). The increased iodine contrast at low tube voltage allows for minimizing iodine load. OBJECTIVE: To assess the effect of reduced x-ray tube voltage, low iodine concentration contrast medium and IR on image quality and radiation dose at CCTA. METHODS: Two hundred thirty-one consecutive patients with suspected coronary artery disease were enrolled in this prospective, multicenter trial and randomized to 1 of 2 dual-source CCTA protocols: 120-kVp with 370 mgI/mL iopromide or iopamidol (n = 116; 44 women; 55.3 ± 9.8 years) or 100 kVp with 270 mgI/mL iodixanol (n = 115; 48 women; 54.2 ± 10.4 years). Reconstruction was performed with filtered back projection and IR. Attenuation, image noise, signal-to-noise ratio, and contrast-to-noise ratio were measured and image quality scored. Size-specific dose estimates and effective doses were calculated. RESULTS: There were no significant differences in mean arterial attenuation (406.6 ± 76.7 vs 409.7 ± 65.2 Hounsfield units; P = .739), image noise (18.7 ± 3.8 vs 17.9 ± 3.4 Hounsfield units; P = .138), signal-to-noise ratio (22.5 ± 5.4 vs 23.7 ± 6.1; P = .126), contrast-to-noise ratio (17.5 ± 5.5 vs 18.3 ± 6.1; P = .286), or image quality scores (4.1 ± 0.9 vs 4.0 ± 0.9; P > .05) between 120-kVp filtered back projection-reconstructed and 100-kVp IR-reconstructed series. Mean iodine dose was 26.5% lower (18.3 ± 0.5 vs 24.9 ± 0.9 g; P < .0001), mean size-specific dose estimate was 35.1% lower (17.9 ± 6.6 vs 27.5 ± 8.2 mGy; P < .0001), and effective dose was 34.9% lower (2.3 ± 1.0 vs 3.5 ± 1.1 mSv; P < .0001) with the 100 kVp compared with the 120-kVp protocol, respectively. CONCLUSION: Using low x-ray tube voltage and IR allows for decreasing the iodine load and effective radiation dose at CCTA while maintaining image quality.

Low-concentration contrast medium for 128-slice dual-source CT coronary angiography at a very low radiation dose using prospectively ECG-triggered high-pitch spiral acquisition.

RATIONALE AND OBJECTIVES: To assess the impact of low-concentration contrast medium on vascular enhancement, image quality, and radiation dose of coronary computed tomography (CT) angiography (CCTA) by using prospectively electrocardiography (ECG)-triggered high-pitch spiral acquisition with low tube voltage in combination with iterative reconstruction. MATERIALS AND METHODS: One hundred patients (body mass index ≤ 25 kg/m(2), heart rate ≤ 65 beats per minute) were prospectively randomized to two groups, with 50 patients each, which were differed by contrast medium. All patients underwent prospectively ECG-triggered high-pitch spiral acquisition CCTA (2 × 128 × 0.6 mm, 300 mAs). Group A patients received iopromide 370 (370 mg I/mL), were scanned using 100 kVp, and reconstructed with filtered back projection. Group B patients received Iodixanol 270 (270 mg I/mL), were scanned using low tube voltage of 80 kVp, and reconstructed with iterative reconstruction techniques (IRT). CT attenuation was measured in coronary artery and other anatomic regions. Image quality score, noise, signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), and radiation dose were calculated and compared. RESULTS: The iodixanol 270 group showed no significant difference in image quality score (1.61 ± 0.69 vs 1.57 ± 0.66; P > .05), CT attenuation (P > .05), noise (P > .05), SNR (47.89 ± 14.03 vs 44.37 ± 12.79; P > .05), and CNR (42.38 ± 12.67 vs 38.13 ± 11.38; P > .05) in comparison to the iopromide 370 group but at a significantly lower radiation dose (0.26 ± 0.05 vs 0.57 ± 0.10; P < .001), which reflects dose saving of 54.4%. CONCLUSIONS: Combining IRT with high-pitch spiral acquisition mode and low-tube-voltage technique, a low-concentration contrast medium of 270 mg I/mL can still maintain the contrast enhancement in coronary arteries without impairing image quality and significantly lower the radiation dose.

Experimental study of endothelial progenitor cells labeled with superparamagnetic iron oxide in vitro.

Endothelial progenitor cells (EPCs) have an essential role in counteracting risk factor­induced endothelial injury and protecting against the development of vascular injury, such as myocardial infarction. Magnetic resonance imaging (MRI) was reported to be effective in tracking transplanted stem cells following cell­labeling with superparamagnetic iron oxide (SPIO) nanoparticles. SPIO has previously been used to label and track EPCs; however, the safest concentration of SPIO for labeling EPCs on a cellular level has remained to be elucidated. In addition, the optimum number of SPIO­labeled cells required to produce the highest quality magnetic resonance images has not yet been determined. In the present study, EPCs were isolated from the bone marrow of minipigs using density gradient centrifugation. Their biological activity was then studied using flow cytometric analysis. Cells were incubated at different concentrations of SPIO for different durations and then the growth curve, apoptosis, morphology and labeling efficiency of the EPCs were detected using optical and electron microscopy. T2­weighted fast spin­echo (T2WITSE) MRI of the different numbers of SPIO­labeled EPCs (35 µg/ml) were then obtained in axial and sagittal planes. The results of the present study demonstrated that EPCs were efficiently labeled with SPIO, with a labeling efficiency in each group of ~100% following incubation for 24 h. SPIO was found to be localized in the endosomal vesicles of EPCs, which was confirmed by electron microscopy. When the concentration of SPIO was <70 µg/ml, no significant differences were observed in cell viability, proliferative capability (P>0.05) and morphology between labeled and unlabeled EPCs. Furthermore, the T2WITSE signal intensity was significantly decreased in the groups of 5.0x105/ml and 1.0x105/ml compared with that of the control (P<0.05). In conclusion, the results of the present study indicated that 35 µg/ml was the most effective concentration of SPIO to label EPCs in vitro and acquire a high quality MRI. These findings may therefore contribute to the development of a promising novel therapeutic method for the treatment of myocardial infarction following autograft with SPIO­labeled EPCs in vivo.

Accuracy, image quality, and radiation dose of prospectively ECG-triggered high-pitch dual-source CT angiography in infants and children with complex coarctation of the aorta.

RATIONALE AND OBJECTIVES: To evaluate the diagnostic accuracy, image quality, and radiation dose of prospective electrocardiogram (ECG)-triggered high-pitch dual-source computed tomography (DSCT) in infants and young children with complex coarctation of the aorta (CoA). MATERIALS AND METHODS: Forty pediatric patients aged < 4 years with suspected CoA underwent prospective ECG-triggered high-pitch DSCT angiography and transthoracic echocardiography (TTE). Surgery and/or conventional cardiac angiography (CCA) were performed in all patients. The diagnostic accuracy of DSCT angiography and TTE was compared to the surgical and/or CCA findings. The causes of misdiagnosis and miss were analyzed, and the advantages and limitation of both imaging modalities were evaluated. Image quality of DSCT was evaluated, and effective radiation dose was calculated. RESULTS: The sensitivity, specificity, positive predictive value, negative predictive value, and overall diagnostic accuracy of DSCT in evaluation of complex CoA were 92.37%, 98.51%, 97.32%, 93.57%, and 96.25%, respectively. There was a significant difference in the accuracy between DSCT and TTE (χ² = 9.9, P＜.05). For a total of 80 extracardiac anomalies, the sensitivity (98.8%, 79/80) of DSCT was greater than that of TTE (62.5%; 50 of 80). On the contrary, for 38 cardiac anomalies, the sensitivity (78.9%, 30 of 38) of DSCT was lesser than that of TTE (100%; 38 of 38). The mean score of image quality was 4.27 ± 0.73. The mean effective radiation dose was 0.20 ± 0.09 mSv. CONCLUSIONS: Prospective ECG-triggered high-pitch DSCT may be a clinical feasible modality in the evaluation of pediatric patients with complex CoA, providing adequate image quality, high diagnostic accuracy, and low radiation dose.

The ascending aortic image quality and the whole aortic radiation dose of high-pitch dual-source CT angiography.

BACKGROUND: Aortic dissection is a lift-threatening medical emergency associated with high rates of morbidity and mortality. The incidence rate of aortic dissection is estimated at 5 to 30 per 1 million people per year. The prompt and correct diagnosis of aortic dissection is critical. This study was to compare the ascending aortic image quality and the whole aortic radiation dose of high-pitch dual-source CT angiography and conventional dual-source CT angiography. METHODS: A total of 110 consecutive patients with suspected aortic dissection and other aortic disorders were randomly divided into two groups. Group A underwent traditional scan mode and Group B underwent high-pitch dual-source CT scan mode. The image quality and radiation dose of two groups were compared. RESULTS: Close interobserver agreement was found for image quality scores (κ = 0.87). The image quality of ascending aorta was significantly better in the high-pitch group than in the conventional group (2.78 ± 0.46 vs 1.57 ± 0.43, P < 0.001). There was no significant difference of the CT attenuation values, the aortic image noise and SNR between two groups. The mean radiation dose of high-pitch group was also significantly lower than that of conventional group (2.7 ± 0.6 mSv vs. 3.9 ± 0.9 mSv, P < 0.001). CONCLUSIONS: High-pitch dual-source CT angiography of the whole aorta can provide motion-artifact-free imaging of the ascending aorta at a low radiation dose compared to conventional protocol.

Dynamic contrast-enhanced MR imaging in a phase â ¡ study on neoadjuvant chemotherapy combining Rh-endostatin with docetaxel and epirubicin for locally advanced breast cancer.

BACKGROUND: Anti-angiogenesis is a promising therapeutic strategy for locally advanced breast cancer. We performed this phase II trial to evaluate the anti-angiogenesis and anti-tumor effect of rh-endostatin combined with docetaxel and epirubicin in patients with locally advanced breast cancer by dynamic contrast-enhanced magnetic resonance imaging in 70 previously untreated locally advanced breast cancer patients. METHODS: The study population was randomly assigned to neoadjuvant chemotherapy with docetaxel and epirubicin (neoadjuvant chemotherapy group) or neoadjuvant chemotherapy combining rh-endostatin with docetaxel and epirubicin (neoadjuvant chemotherapy+rh-endostatin group). The anti-angiogenic and anti-tumor effects of both regimens were evaluated by serial dynamic contrast-enhanced magnetic resonance imaging and microvessel density measurements after final surgery. RESULTS: The results suggested a higher clinical objective response (90.9% vs. 67.7%, P = 0.021) and greater reductions in tumor size (67.2% vs. 55.9%, P = 0.000), Ki-67 proliferation index (32.79% vs. 12.47%, P = 0.000), tumor signal enhanced ratio (64% vs. 48%, P = 0.018), and K(trans) (67% vs. 39%, P = 0.026) in neoadjuvant chemotherapy+rh-endostatin group than those in neoadjuvant chemotherapy group. In addition, the microvessel density value in the neoadjuvant chemotherapy+rh-endostatin group was significantly lower than in the neoadjuvant chemotherapy group (18.67 ± 6.53 vs. 36.05 ± 9.64, P = 0.000). Moreover, the microvessel density value was significantly correlated with K(trans) after neoadjuvant chemotherapy+rh-endostatin treatment (r=0.88, P = 0.00). CONCLUSIONS: The neoadjuvant chemotherapy+rh-endostatin treatment significantly repressed angiogenesis in locally advanced breast cancer and synergistically enhanced the anti-tumor effect of neoadjuvant chemotherapy. Serial dynamic contrast-enhanced magnetic resonance imaging data including reductions in tumor size and K(trans), could provide non-invasive evaluation for chemotherapeutic efficacy and, consequently, optimization of individual chemotherapy for locally advanced breast cancer patients.