Objective:To evaluate the long-term efficacy of percutaneous microwave ablation (MWA) therapy for hepatocellular carcinoma.Methods:2054 cases with Barcelona Clinic Liver Cancer (BCLC) stage 0~B at the Fifth Medical Center of the Chinese People's Liberation Army General Hospital from January 2006 to September 2020 were retrospectively collected. All patients were followed up for at least 2 years. The primary endpoint of overall survival and secondary endpoints (tumor-related survival, disease-free survival, and postoperative complications) of patients treated with ultrasound-guided percutaneous MWA were analyzed. Kaplan-Meier method was used for stratified survival rate analysis. Fine-and-Gray competing risk model was used to analyze overall survival.Results:A total of 5 503 HCC nodules [mean tumor diameter (2.6±1.6) cm] underwent 3 908 MWAs between January 2006 and September 2020, with a median follow-up time of 45.6 (24.0 -79.2) months.The technical effectiveness rate of 5 375 tumor nodules was 97.5%. The overall survival rates at 5, 10, and 15-years were 61.6%, 38.8%, and 27.0%, respectively. The tumor-specific survival rates were 67.1%, 47.2%, and 37.7%, respectively. The free tumor survival rates were 25.8%, 15.7%, and 9.9%, respectively. The incidence rate of severe complications was 2.8% (108/3 908). Further analysis showed that the technical effectiveness and survival rate over the passing three time periods from January 2006-2010, 2011-2015, and 2016-September 2020 were significantly increased, with P ?

Despite being a common therapy for hepatocellular carcinoma (HCC), insufficient thermal ablation can leave behind tumor residues that can cause recurrence. This is believed to augment M2 inflammatory macrophages that usually play a pro-tumorigenic role. To address this problem, we designed d-mannose-chelated iron oxide nanoparticles (man-IONPs) to polarize M2-like macrophages into the antitumor M1 phenotype. In vitro and in vivo experiments demonstrated that man-IONPs specifically targeted M2-like macrophages and accumulated in peri-ablation zones after macrophage infiltration was augmented under insufficient microwave ablation (MWA). The nanoparticles simultaneously induced polarization of pro-tumorigenic M2 macrophages into antitumor M1 phenotypes, enabling the transformation of the immunosuppressive microenvironment into an immunoactivating one. Post-MWA macrophage polarization exerted robust inhibitory effects on HCC progression in a well-established orthotopic liver cancer mouse model. Thus, combining thermal ablation with man-IONPs can salvage residual tumors after insufficient MWA. These results have strong potential for clinical translation.

Objective To evaluate the left atrial(LA) function in patients with severe preeclampsia ( SPE) by full-volume imaging technology. Methods Forty-two patients of SPE were randomly chosen as SPE group,34 healthy pregnant women were selected as the control group. LA related function parameters including LA maximum volume( LAVmax),LA minimum volume( LAVmin),LA pre-atrium contraction volume(LAVpre),LA reservoir volume(LARV),LA passive emptying volume(LAPEV),LA contraction volume(LACV),LA expansion index(LAEI),LA passive emptying fraction(LAPEF),LA passive emptying fraction( LAAEF ) were separately required by biplane area-length method and full-volume imaging technology in antepartum and postpartum. Results Compared with control group before delivery,the parameters of SPE group before delivery such as LAVmax,LAVmin,LAVpre were higher,LAEI,LAPEF, LAAEF indexed to body surface area(BSA) were lower(all P ＜0.01).Compared with control group before delivery,the parameters of control group after delivery such as LAVmax,LAVmin,LAVpre were lower( all P ＜0.05),LAEI, LAAEF calculated as ratio to BSA were somewhat reduced,LAPEF calculated as ratio to BSA was relatively higher(all P ＞0.05).Compared with SPE group before delivery,the parameters of SPE group after delivery such as LAVmax,LAVmin,LAVpre were lower,LAEI,LAPEF,LAAEF indexed to BSA were higher( all P ＜0.01). Compared with control group after delivery,the parameters of SPE group after delivery such as LAVmax,LAVmin,LAVpre were still incresed ( all P ＜ 0.05 ), LAEI,LAPEF, LAAEF indexed to BSA were relatively lower( all P ＞0.05). Conclusions Full-volume imaging technology can quantitatively evaluate the LA function. LA reservoir function,conduit function and booster pump function are reduced in SPE before delivery,LA rereservoir function,conduit function and booster pump function are basically recovery in SPE after delivery.

Objective To investigate the feasibility of low-dose CT perfusion imaging(CTPI)examination combined with iterative model reconstruction (IMR) in the brain.Methods 80 patients with clinical suspicion of acute cerebral infarction underwent the cerebral CTPI were enrolled in this study.30 normal hemispheres on group A [35 cases,80 kV,150 mAs, filtered back projection(FBP)] and group B(45 cases,80 kV,30 mAs, IMR) were selected to evaluate respectively.The pictures' subjective scores, effective radiation dose (ED),CT value,SD,signal to noise ratio(SNR), contrast to noise ratio(CNR) and the perfusion parameters of the grey matter (GM) and white matter(WM) in each hemisphere of the middle cerebral artery(MCA) territory were respectively compared at ASPECTS level 2 for the two groups.Results The ED were 2.52,0.50 mSv for group A,B.There were no statistical significances in the perfusion parameters,CT value, SD, CNR of the ROIs of the GM and WM,the SNR of the ROIs of the GM and the pictures' subjective scores between group A, B (P>0.05).There was statistical significance in the SNR of the ROIs of the WM between group A,B (P<0.05).Conclusion IMR combined with 30 mAs of the CTPI can reduce the radiation dose apparently while maintain the stability of the image quality and perfusion parameters.

Objective To explore the new method for noninvasively measuring the time constant of left ventricular relaxation (Tau) in animals with mitral regurgitation by continuous-wave Doppler.Methods The acute ischaemic left diastolic heart failure with mitral regurgitation was produced in 9 dogs.Dobutamine hydrochloride or esmolol hydrochloride had been applied to change the hemodynamic states.In different hemodynamic states,left ventricular pressures,left atrial pressures,curves of dP/dt and continuous-wave mitral regurgitant spectra were synchronously recorded.Doppler spectra were laterly processed through Matlab workstation.Paired t-test was used to compare the difference between Tau-catheter (Tau-c) and Tau-doppler ultrasound (Tau-d),and the correlation between Tau-c and Tau-d was analyzed by Pearson correlation analysis.Results Thirty-nine hemodynamic status had been obtained in 9 dogs.Tau-c was 21.03-78.45 ms and the average was (48.76± 17.60) ms.Tau-d was 21.24-94.60 ms and the average was (49.33 ± 18.79) ms.There was no significant difference (t=0.353,P=0.726) between Tau-d and Tau-c.The correlation analysis between Tau-d and Tau-c suggested a strong positive relationship with the correlation coefficient (r=0.85,P ＜ 0.001).Conclusions The dog aortic regurgitation model under ultrasound guidance is less traumatic.The method of inducing left ventricular diastolic dysfunction by repeatedly injecting microspheres into the left coronary sinus is safe and reliable.Choosing three points (t1,1 m/s;t2,2 m/s;t3,3 m/s) in aortic regurgitant velocity spectrum and putting them into the corresponding formula,we can obtain Tau,which had a good correlation with the catheter-derived Tau.

Objective To find a new method for evaluating the left ventricular relaxation time constant Tau with aortic regurgitation by continuous wave Doppler.Methods Twelve Beagle dogs were included in the study.The dog aortic regurgitation model was produced under ultrasound guiding by carotid artery puncture.Aortic pressure was measured by pressure catheter and left ventricular pressure was measured by Millar catheter which was introduced into the left ventricular through cardiac apex.Then microspheres were injected into the left coronary artery under the guidance of ultrasound to induce acute ischemic left ventricular dysfunction,when left ventricular end-diastolic pressure increased more than 5 mmHg (1 mmHg=0.133 kPa).Dobutamine or esmolol was infused to alter left ventricular function.Aortic regurgitation velocity spectrum was recorded by the continuous-wave Doppler echocardiography in different hemodynamic status.At the same time,left ventricular pressure,dp/dt,aortic pressure and continuous ECG tracing were displayed on the multi-channel physiological recorder.Measurement was recorded of-dp/dtmax in the dp/dt tracings and the pressure at the time of-dp/dtmax in the left ventricular pressure tracings.Tau =-P/(dp/dtmax),Tau was the catheter-derived time constant (Taucatheter).Aortic regurgitation spectrum of original audio data was post-processed with MATLAB mathematical software.The spectral lines refresh time of about 300 μs was chosen to form a new Doppler spectrum.Three points:(t1,1 m/s),(t2,2 m/s) and (t3,3 m/s) were selected in aortic regurgitation velocity spectrum and tl,t2 and t3 was put into the corresponding Tau formula:Tau=(t2-t1)/ln[(ADP-C-4)/(ADP-C-16)],Tau=(t3-t1)/ln[(ADP-C-4)/(ADP-C-36)].Tau was the aortic regurgitant time constant (Tauultrasound).The difference between Taucatheter and Tauultrasound was compared by paired t test.The correlation between Taucatheter and Tauultrasound was analyzed by Pearson correlation analysis.Results Twelve dogs were successfully produced aortic regurgitation model.Two dogs died of ventricular fibrillation during the procedure of acute ischemic left ventricular diastolic dysfunction.The range of the Taucatheter was between 27.12 ms and 86.88 ms with an average of (48.973± 14.667) ms;the range of the Tauultrasound was between 28.13 ms and 90.18 ms with an average of (51.236± 15.146) ms.The difference was not statistically significant (t=1.841,P ＞ 0.05).Pearson correlation analysis showed that Taucatheter was positively correlated with Tatultrasound (r=0.89,P=0.000).Conclusion Choosing three points:(t1,1 m/s),(t2,2 m/s) and (t3,3 m/s) in aortic regurgitant velocity spectrum and putting into the corresponding formula,we can calculate Tau,which had a good correlation with the catheter-derived Tau.

Objective To investigate the feasibility of iterative model reconstruction (IMR) combined with low tube voltage and low iodine intaken of contrast media in head and neck CT angiography (CTA). Methods Eighty patients with clinical suspicion of head and neck vascular disease underwent head and neck CTA were enrolled in this prospective study. According to random number table, patients were randomly divided into two groups. Group A (n=40) was scanned according to the protocol of 120 kV, 50 ml iopromide (370 mg/ml) and filtered back projection (FBP) reconstruction, and group B (n=40) was scanned with 80 kV, 30 ml iohexol (300 mg/ml) and IMR, while the other parameters kept consistent. Mann-Whitney U test was used to compare the enhanced CT value of arteries, image noise, signal noise ratio (SNR), contrast noise ratio (CNR), the score of image quality, effective radiation dose (ED) and iodine intaken of contrast media between two groups. Results The CT value at the origin level of common carotid artery were (316.9 ± 53.0) and (433.4 ± 101.8)HU in group A and B, image noise were (28.1 ± 6.8)and (12.1 ± 2.6)HU ,SNR were (11.9 ± 3.2) and (37.7 ± 13.3) ,and CNR were (10.2 ± 2.9) and (32.6 ± 13.3), respectively. There were showed significant differences in CT value, image noise, SNR and CNR between two groups (Z=-5.490,-7.592,-7.698,-7.660, P<0.05). The CT value at the origin level of internal carotid artery were (359.5 ± 54.3) and (443.5 ± 120.1) HU in group A and B, image noise were (18.8±6.2) and (6.8±1.7) HU ,SNR were 21.5±8.7 and 69.7±27.4 ,and CNR were 18.0±7.3 and 62.7± 26.4, respectively. The significant differences were acquired in CT value, image noise, SNR and CNR between two groups (Z=-3.022,-7.376,-7.496,-7.515, P<0.05). The CT value at M1 segment level of middle cerebral artery were (321.1±47.3) and (401.6±104.0) HU in group A and B, image noise were (32.3± 17.2) and (11.2 ± 2.7) HU,SNR were 12.4 ± 5.6 and 39.3 ± 18.4,and CNR were 10.7 ± 4.7 and 36.4 ± 17.7, respectively. There also showed significant differences in CT value, image noise, SNR and CNR between two groups (Z=-3.527,-7.487,-7.482,-7.535, P<0.05). The score of image quality of group A and B were 3.9 ± 0.7 and 4.5±0.6, which also showed significant difference between two two groups (Z=-3.517, P<0.05). The ED were (2.78 ± 0.13) and (0.84 ± 0.04) mSv for group A and B, which also showed significant difference between the two groups (Z=-7.706, P<0.05). The iodine intaken of contrast media were 1.85 g and 0.90 g in group A and B. Conclusion IMR combined with low tube voltage and low iodine intaken of contrast media can not only decrease effective radiation dose and iodine intaken of contrast media significantly, but also improve the imaging quality in head and neck CTA examination.

Medical imaging is an interdisciplinary subject closely related to clinical and pathological subject. Its clinical reading skills' training has become the focus of postgraduate teaching. In the process of clinical teaching, the interactive reading mode of problem-based learning (PBL) combined with multi-disci-plinary team (MDT) was introduced into clinical reading meeting. The tutors chose the reading cases proved by pathology; designed in-depth issues step by step for execution of PBL teaching; guided postgraduates to delineate imaging signs and propose the diagnostic results, evidences and differential diagnoses according to the step from localizing to qualitative and then to pathological diagnosis;then guided postgraduates to attend in-depth case analysis of MDT and analyze the correlation or inconsistency between the imaging diagnosis and clinical and pathological diagnosis; exercise document retrieval and verbalization, multimedia design, and writing level of the records of the reading cases and papers. The interactive reading mode of PBL com-bined with MDT has achieved significant effects, which is worthy of further exploration and promotion.

Objective To evaluate the diagnostic value of ultrasound-guided pleural biopsy combined with thoracic biochemical detections in malignant and tuberculous pleural effusions. Methods Sixty-four patients with moderate or large pleural effusions and pleural thickening received the ultrasound-guided diagnostic pleural biopsy. All patients had chest CT enhancement scans to find out the suspicious pleural thickening preoperatively, facilitating the selection of puncture sites by ultrasound. Pleural tissue samples were sent for pathological examinations immediately. After successful achievements of pleural biopsy, ultrasound-guided aspiration or drainage was performed to alleviate symptoms, more importantly, to get pleural effusions for biochemical analysis. Biological results including carcinoembryonic antigen(CEA), CA125, CYFRA21 and lactate dehydrogenase(LDH) in malignant and tuberculous effusions were analyzed by group design t tests. The positive rates of CEA, CA125, CYFRA21, LDH in malignant and tuberculous effusions were compared by chi square tests. Results Pleural tissues in all cases were got by one pleural biopsy procedure. The strategy of pleural biopsy we used in this study had a successful rate reaching 100%(64/64), and 73% (46/64) patients had a definitive diagnosis as malignant or tuberculous effusion. Twenty-seven cases were diagnosed as malignant effusions and thirty-seven cases as tuberculous effusions based on the deifnitive clinical diagnosis. The positive rates of CEA, CA125, CYFRA21, LDH in malignant effusions were 100%(27/27), 100%(27/27), 100%(27/27), 89%(24/27) respectively, and 0%(0/37), 84%(31/37), 78%(29/37), 76%(28/37) respectively in tuberculous effusions. The positive rate of CEA between malignant and tuberculous effusions differed signiifcantly (χ2=64.0, P < 0.01), so did CA125 (χ2=3.1, P < 0.01) and CYFRA21(χ2=4.8, P<0.01). The average levels of CEA, CA125, CYFRA21, LDH in pleural effusion were (727.1±658.8)μg/L, (795.2±1249.6)×103 U/L, (296.2±320.7)μg/L, (1077.9±1058.5) U/L respectively, and (1.7±1.1)μg/L, (336.3±208.6)×103 U/L, (20.7±14.9)μg/L, (309.2±182.7) U/L in tuberculous effusions.There were signiifcant differences in CEA, CYFRA21 and LDH concentrations among malignant and tuberculous effusions (t=45.1, 27.4, 18.8 respectively, all P<0.01). Conclusion Ultrasound-guided pleural biopsy combined with CEA, CYFRA21 and LDH in pleural effusions had an important value in the etiological diagnosis of pleural effusions, while CA125 showed little value in the differential diagnosis.