Evaluation of suspicious breast lesions with diffusion kurtosis MR imaging and connection with prognostic factors.

PURPOSE: To investigate the additional value of DKI in discriminating suspicious breast lesions on DCE-MRI, as compared with conventional DWI; and to explore connection between DKI-parameters and prognostic factors of breast cancers. METHODS: The institutional review board approved this retrospective study and written informed consent was waived. Totally, 300 women (mean age, 43.2 ± 10.4 years) with suspicious breast lesions on DCE-MRI were enrolled from November 2014 to September 2019. With pathology as reference, performance of ADC, Kapp and Dapp in discriminating suspicious breast lesions were analyzed by receiver operating characteristic (ROC) analysis with area under ROC curve (AUC). The specificities of parameters were compared by Chi-square test. The ADC, Kapp and Dapp of breast cancers with different receptor status were compared using Student's t or Mann-Whitney U or Kruskal-Wallis test. RESULTS: There were 344 suspicious breast lesions (220 malignant, 124 benign) in 300 women. No significant differences were found for AUCs of ADC and DKI-parameters in discriminating suspicious breast lesions (0.882 vs. 0.888, p = 0.480). The specificities were significantly higher with ADC and Dapp than that with DCE-MRI (p = 0.003 and 0.005). The ADC, Kapp and Dapp were correlated with HER2 expression and lymph node status, and ADC and Kapp differed between ER-positive and negative tumors (all p < 0.05). Except Kapp, DKI/DWI-parameters showed relation with Ki-67 expression. None of the DKI/DWI-parameters showed relation with lesion grade (all p > 0.05). CONCLUSION: The more complicated and time-consuming DKI is not superior to conventional DWI in differentiating suspicious breast lesions and reflecting prognostic information of breast cancer.

Detection and Classification of Breast Lesions With Readout-Segmented Diffusion-Weighted Imaging in a Large Chinese Cohort.

Objectives: To evaluate the performance of readout-segmented echo-planar imaging DWI (rs-EPI DWI) in detecting and characterizing breast cancers in a large Chinese cohort with comparison to dynamic contrast-enhanced MRI (DCE-MRI). Methods: The institutional review board approved this retrospective study with waived written informed consent. A total of 520 women (mean age, 43.1- ± 10.5-years) were included from July 2013 to October 2019. First, the ability of rs-EPI DWI in detecting breast lesions identified by DCE-MRI was evaluated. The lesion conspicuity of rs-EPI-DWI and DCE-MRI was compared using the Wilcoxon signed rank test. With pathology as a reference, the performance of rs-EPI DWI and DCE-MRI in distinguishing breast cancers was evaluated and compared using the Chi-square test. Results: Of 520 women, 327/520 (62.9%) patients had 423 lesions confirmed by pathology with 203 benign and 220 malignant lesions. The rs-EPI DWI can detect 90.8% (659/726) (reader 1) and 90.6% (663/732) (reader 2) of lesions identified by DCE-MRI. The lesion visibility was superior for DCE-MRI than rs-EPI-DWI (all p < 0.05). With pathology as a reference, the sensitivities and specificities of rs-EPI DWI in diagnosing breast cancers were 95.9% (211/220) and 85.7% (174/203) for reader 1 and 97.7% (215/220) and 86.2% (175/203) for reader 2. No significant differences were found for the performance of DCE-MRI and rs-EPI DWI in discriminating breast cancers (all p > 0.05). Conclusions: Although with an inferior lesion visibility, rs-EPI DWI can detect about 90% of breast lesions identified by DCE-MRI and has comparable diagnostic capacity to that of DCE-MRI in identifying breast cancer.

Fibrotic Changes Depicted by Thin-Section CT in Patients With COVID-19 at the Early Recovery Stage: Preliminary Experience.

Objectives: To analyze follow-up CTs of patients recovering from COVID-19 in Wuhan, focusing on fibrotic change and its relevant risk factors. Methods: From January 13 to February 27, 2020, 166 hospitalized patients meeting our criteria were included. The scores of fibrotic patterns on follow-up CT were evaluated. Patients were designated as group 1 (with CT evidence of fibrotic pattern) and group 2 (without CT evidence of fibrotic pattern). Multivariate logistic regression was performed to explore risk factors for fibrotic change in patients with COVID-19. Results: The follow-up CTs were obtained on 56 days (median, IQR 51-63 days) after symptom onset. Of the 166 patients (mean age, 57 ± 15 years; 69/166 male), 46% (76/166) had CT evidence of fibrotic change and 77% (127/166) were severe or critical cases. Among patients with fibrotic change on CT, 84% (64/76) got a minimal or mild score of fibrosis. The high total score on peak CT, peak eosinophils, erythrocyte sedimentation rate (ESR) and advancing age were related to lung fibrotic change in patients with COVID-19. Conclusion: Forty six percentages of patients (mainly severe or critical cases) with COVID-19 showed fibrotic change on follow-up CT at early recovery phase, while the extent of fibrosis was not large. The advancing age, high total score on peak CT, peak eosinophils and ESR were associated with fibrotic change depicted by CT in patients recovering from COVID-19. An extended follow up by CT imaging and pulmonary function testing is necessary to fully assess the sequela of COVID-19.

Oxygen-Evolving Mesoporous Organosilica Coated Prussian Blue Nanoplatform for Highly Efficient Photodynamic Therapy of Tumors.

Oxygen (O2) plays a critical role during photodynamic therapy (PDT), however, hypoxia is quite common in most solid tumors, which limits the PDT efficacy and promotes the tumor aggression. Here, a safe and multifunctional oxygen-evolving nanoplatform is costructured to overcome this problem. It is composed of a prussian blue (PB) core and chlorin e6 (Ce6) anchored periodic mesoporous organosilica (PMO) shell (denoted as PB@PMO-Ce6). In the highly integrated nanoplatform, the PB with catalase-like activity can catalyze hydrogen peroxide to generate O2, and the Ce6 transform the O2 to generate more reactive oxygen species (ROS) upon laser irradiation for PDT. This PB@PMO-Ce6 nanoplatform presents well-defined core-shell structure, uniform diameter (105 ± 12 nm), and high biocompatibility. This study confirms that the PB@PMO-Ce6 nanoplatform can generate more ROS to enhance PDT than free Ce6 in cellular level (p < 0.001). In vivo, the singlet oxygen sensor green staining, tumor volume of tumor-bearing mice, and histopathological analysis demonstrate that this oxygen-evolving nanoplatform can elevate singlet oxygen to effectively inhibit tumor growth without obvious damage to major organs. The preliminary results from this study indicate the potential of biocompatible PB@PMO-Ce6 nanoplatform to elevate O2 and ROS for improving PDT efficacy.

Small Intracranial Aneurysms: Diagnostic Accuracy of CT Angiography.

Purpose To assess the accuracy of computed tomographic (CT) angiography for diagnosis of cerebral aneurysms 5 mm or smaller, with digital subtraction angiography (DSA) as the reference standard, in a large patient cohort Materials and Methods This retrospective study was approved by the local institutional review board with a waiver of written informed consent. A total of 1366 patients who underwent cerebral CT angiography followed by DSA were included. The performance of CT angiography for depiction of aneurysms was evaluated by two readers on a per-patient and per-aneurysm basis and based on size of aneurysm, location, and status of rupture. The performance of CT angiography for diagnosis of aneurysms of different size, location, and rupture status was compared by using χ2 test. κ statistic was used to assess interreader agreement for diagnosis of aneurysms. Results Of 1366 patients, 579 patients had 711 small aneurysms at DSA. By using DSA as the reference standard, the respective sensitivity, specificity, and accuracy of CT angiography for readers 1 and 2 for detection of small aneurysms on a per-patient basis were 97.1% (562 of 579) and 97.4% (564 of 579), 98.5% (451 of 458) and 99.1% (454 of 458), and 97.7% (1013 of 1037) and 98.2% (1018 of 1037) and those on a per-aneurysm basis were 95.2% (677 of 711) and 95.4% (678 of 711), 96.6% (451 of 467) and 97.0% (454 of 468), and 95.8% (1128 of 1178) and 96.0% (1132 of 1179). The sensitivities of CT angiography were lower for detection of aneurysms smaller than 3 mm and unruptured compared with aneurysms that were 3-5 mm and ruptured (P < .001). No difference existed for the sensitivities of CT angiography for diagnosis of aneurysms in the anterior versus posterior circulation (P > .0167). Excellent or good interreader agreement was found for detection of intracranial aneurysms on a per-patient (κ = 0.982) and per-aneurysm (κ = 0.748) basis. Conclusion This large cohort study demonstrated that CT angiography had high accuracy for detection of small cerebral aneurysms, including those smaller than 3 mm. © RSNA, 2017 Online supplemental material is available for this article.

Radiology research in mainland China in the past 10 years: a survey of original articles published in Radiology and European Radiology.

PURPOSE: To evaluate the features and trends of Radiology research in Mainland China through bibliometric analysis of the original articles published in Radiology and European Radiology (ER) between 2006 and 2015. MATERIALS AND METHODS: We reviewed the original articles published in Radiology and ER between 2006 and 2015. The following information was abstracted: imaging subspecialty, imaging technique(s) used, research type, sample size, study design, statistical analysis, study results, funding declarations, international collaborations, number of authors, department and province of the first author. All variables were examined longitudinally over time. RESULTS: Radiology research in Mainland China saw a substantial increase in original research articles published, especially in the last 5 years (P < 0.001). Within Mainland China's Radiology research, neuroradiology, vascular/interventional Radiology, and abdominal Radiology were the most productive fields; MR imaging was the most used modality, and a distinct geographic provenience was observed for articles published in Radiology and ER. CONCLUSION: Radiology research in Mainland China has seen substantial growth in the past 5 years with neuroradiology, vascular/interventional Radiology, and abdominal Radiology as the most productive fields. MR imaging is the most used modality. Article provenience shows a distinct geographical pattern. KEY POINTS: • Radiology research in Mainland China saw a substantial increase. • Neuroradiology, vascular/interventional Radiology, and abdominal Radiology are the most productive fields. • MRI is the most used modality in Mainland China's Radiology research. • Guangdong, Shanghai, and Beijing are the most productive provinces.

PET/MRI of central nervous system: current status and future perspective.

UNLABELLED: Imaging plays an increasingly important role in the early diagnosis, prognosis prediction and therapy response evaluation of central nervous system (CNS) diseases. The newly emerging hybrid positron emission tomography/magnetic resonance imaging (PET/MRI) can perform "one-stop-shop" evaluation, including anatomic, functional, biochemical and metabolic information, even at the molecular level, for personalised diagnoses and treatments of CNS diseases. However, there are still several problems to be resolved, such as appropriate PET detectors, attenuation correction and so on. This review will introduce the basic physical principles of PET/MRI and its potential clinical applications in the CNS. We also provide the future perspectives for this field. KEY POINTS: • PET/MRI can simultaneously provide anatomic, functional, biochemical and metabolic information. • PET/MRI has promising potential in various central nervous system diseases. • Research on the future implementation of PET/MRI is challenging and encouraging.