Objective To observe the value of artificial intelligence iterative reconstruction(AIIR)for reconstruction CT images of phantoms.Methods AIIR was developed through combining model-based iterative reconstruction(MBIR)with deep learning(DL)techniques.CT scanning of CCT MITA IQ phantom,CT ACR 464 phantom,Catphan 700 phantom,disc stack phantom and CT PBU-60 whole body phantom were performed,and the images were reconstructed with conventional algorithms like filtered back projection(FBP)and KARL 3D iterative reconstruction,as well as AIIR,respectively.Then the noise,X-ray dosage,as well as low contrast resolution,high contrast spatial resolution,cone-beam artifacts and streaking artifacts of various reconstructed images were compared.Results Compared to CT images reconstructed with conventional algorithms,those reconstructed with AIIR showed 61.74％—99.76％ reduction of image noise and 60.00％—90.00％ reduction of X-ray dosage,while increased image low contrast resolution to 1.99-4.86 times and high contrast spatial resolution to 1.55-2.57 times.Additionally,AIIR significantly reduced cone-beam artifacts and streaking artifacts.Conclusion AIIR showed obvious advantages for reconstruction CT images of phantoms compared with conventional algorithms.

Objective To observe the value of artificial intelligence iterative reconstruction(AIIR)for reconstruction CT images of phantoms.Methods AIIR was developed through combining model-based iterative reconstruction(MBIR)with deep learning(DL)techniques.CT scanning of CCT MITA IQ phantom,CT ACR 464 phantom,Catphan 700 phantom,disc stack phantom and CT PBU-60 whole body phantom were performed,and the images were reconstructed with conventional algorithms like filtered back projection(FBP)and KARL 3D iterative reconstruction,as well as AIIR,respectively.Then the noise,X-ray dosage,as well as low contrast resolution,high contrast spatial resolution,cone-beam artifacts and streaking artifacts of various reconstructed images were compared.Results Compared to CT images reconstructed with conventional algorithms,those reconstructed with AIIR showed 61.74％—99.76％ reduction of image noise and 60.00％—90.00％ reduction of X-ray dosage,while increased image low contrast resolution to 1.99-4.86 times and high contrast spatial resolution to 1.55-2.57 times.Additionally,AIIR significantly reduced cone-beam artifacts and streaking artifacts.Conclusion AIIR showed obvious advantages for reconstruction CT images of phantoms compared with conventional algorithms.

Objective To evaluate the global and segmental (inflow,body and outflow) systolic functions of right ventricle in end-stage renal failure (ESRF) patients by real-time three-dimensional echocardiography(RT-3DE) and four-dimensional right ventricle quantitative analysis (4D-RVQ) and to reveal the long-term impact of renal insufficiency on right ventricular systolic function.Methods RT-3DE was performed in 48 ESRF patients and 26 healthy individuals (control group).Images were acquired and analysed off-line in TomTec 4D-RVQ station.The parameters of RV global and segmental systolic functions,including RV global and segmental end-diastolic volume (EDV),end-systolic volume(ESV),stroke volume(SV),ejection fraction(EF),the time to minimum systolic volume(T-msv) were obtained.All the variables were standardized by body surface area (BSA) or heart rate (HR).Results ① In the ESRF group,EDV,SV and EF of body compartment were significantly higher than those of the controls[EDV:(8.5±3.4)ml/m2 vs (6.4± 1.7)ml/m2,P =0.002;SV:(4.5 ± 1.7)ml/m2 vs (2.7±0.9)ml/m2,P =0.0037;EF:(45.4 ± 11.5)％ vs (41.1 ± 7.1)％,P =0.0489],and so were EDV,SV of inflow compartment [EDV:(19.6± 1.0)ml/m2 vs (16.5±0.9)ml/m2,P =0.0438;SV:(12.3±4.6)ml/m2 vs (10.1±3.2) ml/m2,P =0.0433].②Compared with the control group,the global and segmental T-msv were all delayed obviously in the ESRF group (P ＜ 0.001).③The percentage of SV of body compartment accounting for the global SV significantly increased in the ESRF group [(19.5 ± 7.3)％ vs (15.5 ± 5.5)％,P =0.0222],while that of outflow compartment reduced significantly [(20.3 ± 7.0)％ vs (26.8 ± 8.2)％,P =0.0005].Conclusions The global and segmental systolic functions of right ventricle were impaired in ESRF patients,especially in the body compartment.The RT-3DE and 4D-RVQ are helpful technologies in the evaluation and follow-up of right ventricular systolic function in patients with renal failure.

Objective To evaluate left ventricular torsion and systolic function of the segment by speckle tracking imaging(STI) and real-time three-dimensional echocardiography(RT-3DE) in patients with heart transplantation. Methods Twenty patients with heart transplantation and twenty subjects with normal left ventricular function were examined by Philips iE33 with a X3-1 probe and GE Vivid 7 with M4S probe.Results There were two subjects(100% ) with clockwise rotation in control group patients, but eight patients (40 % ) with clockwise rotation in heart transplantation group. And heart transplantation group were divided into two sub-groups (group A with counterclockwise rotation and group B with clockwise rotation) based on the direction of rotation. In apical level,the systolic peak of the angle of rotation of anterior septum,posterior wall,inferior wall, posterior septum in group A was less than that of control group( P ＜0.05), all segmental systolic peak of the angle of rotation in group B was reduced compared with control group( P ＜0. 05),however all segmental systolic peak of rate of rotation in group A and group B was not significant different compared with control group ( P ＞0. 05) ,all segmental diastolic peak in early and late of rate of rotation in group B was obviously higher than that in control group and group A ( P ＜0. 05), while all segmental diastolic peak in early and late of rate of rotation in group A was not significant different compared with control group( P ＞0.05). The displacement and the parameter index of 17 segment time to minimal systolic volume in group A and group B were not significant different compared with control group( P ＞0. 05), but left ventricular angle of torsion was decreased in group B compared with control group and group A( P ＜0.05). Conclusions STI and RT-3DE can rapidly evaluate function of left ventricular torsion and function of segmental systole and systolic synchrony in patients with heart transplant.

Objective To investigate the feasibility of ultrasound speckle tracking imaging(STI)in assessing left ventricular(LV)systolic and twist function in patients with heart transplantation.Methods Nine patients with heart transplantation and 10 subjects with normal LV function were examined by GE Vivid 7 with a M3S probe.Eighteen regional peak systolic strain and displacement in longitudinal,radial,circumferential,and 18 regional degree of rotation were measured respectively.Results The segmental regional peak systolic strain and displacement were less than those in subjects with normal LV function(P ＜0.05),but segmental regional degree of rotation was more than that in subjeets with normal LV function (P＜0.05).Conclusions STI may provide a noninvasive,simple and quick tool for evaluation of left ventricular systolic and twist function in patients with heart transplantation.

OBJECTIVETo evaluate the role of methylenetetrahydrofolate reductase (MTHFR) gene polymorphisms and plasma homocysteine levels in patients with type 2 diabetes mellitus and diabetic retinopathy (DR).

METHODSTotal of 208 patients with type 2 diabetes mellitus and 57 controls were recruited into the study. MTHFR genetic C677T polymorphisms were determined by PCR-RFLP. Plasma total homocysteine levels were measured using high-performance liquid chromatography (HPLC) with fluorescence detection.

RESULTSThe frequencies of MTHFR TT homogeneous type, CT heterogeneous type and allele T (28.18%, 41.82%, 49.09%) were significantly higher in the type 2 diabetes mellitus with diabetic retinopathy group than those without retinopathy (18.37%, 29.59%, 33.16%) and those of controls (17.54%, 28.07%, 31.58%). The presence of the T allele appeared to have a strong association with the development of diabetic retinopathy. The odds ratio was 1.94 with a 95% confidence interval of 1.31 - 2.88. Moreover, plasma homocysteine levels were remarkably higher in patients with TT or CT genotype than in patients with the CC genotype.

CONCLUSIONMTHFR gene C677T mutation associated with a predisposition to increased plasma homocysteine levels may be considered as a genetic risk factor for diabetic microangiopathy (such as DR) in Chinese patients with type 2 diabetes mellitus.

Aged ; Diabetes Mellitus, Type 2 ; complications ; Diabetic Retinopathy ; etiology ; Female ; Genotype ; Homocysteine ; blood ; Humans ; Male ; Methylenetetrahydrofolate Reductase (NADPH2) ; Middle Aged ; Mutation ; Oxidoreductases Acting on CH-NH Group Donors ; genetics ; Polymorphism, Genetic

OBJECTIVETo evaluate the role of methylenetetrahydrofolate reductase (MTHFR) gene polymorphisms and plasma homocysteine levels in Chinese patients with type 2 diabetes mellitus and diabetic retinopathy (DR).

METHODSMTHFR genetic C677T polymorphisms were determined by PCR-restriction fragment length polymorphism. Total plasma homocysteine levels were measured using high-performance liquid chromatography (HPLC) with fluorescence detection.

RESULTSThe frequencies of MTHFR T homogenetic type and CT heterogenetic type and allele T (28.18%, 41.82%, 49.09%) in type 2 diabetic patients with diabetic retinopathy were significantly higher than those in diabetic patients without retinopathy (18.37%,29.59%,33.16%) or the normal controls (17.54%, 28.07%, 31.58%). Howerver, there were no significant differences in the frequency of MTHFR genotype and allele between the type 2 diabetic patients without retinopathy and the normal controls. The presence of T allele appeared to have a strong association with the development of diabetic retinopathy. The odds ratio was 1.94 and the 95% confidence interval was 1.31-2.88. Moreover, the plasma homocysteine levels in patients with TT or CT genotype were markedly higher than those in patients with CC genotype.

CONCLUSIONMTHFR gene C677T mutation associated with a predisposition to increase of plasma homocysteine may represent a genetic risk factor for diabetic retinopathy in Chinese type 2 diabetes mellitus.

Adult ; Alleles ; DNA ; genetics ; metabolism ; Deoxyribonucleases, Type II Site-Specific ; metabolism ; Diabetes Mellitus, Type 2 ; blood ; complications ; genetics ; Diabetic Retinopathy ; blood ; etiology ; genetics ; Female ; Gene Frequency ; Genotype ; Homocysteine ; blood ; Humans ; Male ; Methylenetetrahydrofolate Reductase (NADPH2) ; Middle Aged ; Oxidoreductases Acting on CH-NH Group Donors ; genetics ; Point Mutation ; Polymorphism, Genetic