Objective To evaluate the lung V/Q imaging in the diagnosis of chronic thromboembolic pulmonary hypertension (CTEPH).Methods Seventy-six patients (46 males,30 females,age 27-84 y) with clinically suspected CTEPH who had undergone lung V/Q imaging,CT pulmonary angiography (CTPA),pulmonary angiography (PA) and right heart cardiac catheterization were studied.The sensitivity,specificity,accuracy,positive predictive value and negative predictive value of lung V/Q imaging in detecting CTEPH were calculated and compared with those of CTPA.The x2 test was used for statistical analysis with SPSS 11.5.The distribution of involvement of segments in 47 patients with CTEPH was analyzed.Results Forty-seven patients had a final diagnosis of CTEPH and 29 had non-CTEPH etiology.The sensitivity,specificity,accuracy,positive predictive value and negative predictive value of lung V/Q imaging were 97.9％ (46/47),86.2％ (25/29),93.4％ (71/76),92.0％ (46/50) and 96.2％ (25/26),while those of CTPA were 78.7％ (37/47),93.1％ (27/29),84.2％ (64/76),94.9％ (37/39) and 73.0％ (27/37),respectively.The sensitivity (x2 =5.818,P=0.012) and negative predictive value (x2 =5.693,P =0.017) for lung V/Q imaging were significantly higher than those of CTPA.V/Q imaging could identify patients with CTEPH from those with idiopathic PAH and familial PAH based on the almost normal ventilation imaging.The lung perfusion SPECT imaging detected 585 (62.2％) of involved segments among 940 segments in 47 patients with CTEPH,with an average of 12.4 involved segments in each patient.The number of involved segments in the right lung was significantly higher than that in the left lung (36.2％ (340/940) vs 26.1％ (245/940) ; x2 =40.85,P＜0.01).Conclusions Lung V/Q imaging plays an important role in diagnosis of CTEPH and in identification of CTEPH from other types of PAH.A normal V/Q imaging can effectively exclude CTEPH.In addition,V/Q imaging can provide more diagnostic information in patients with a clinical suspicion of CTEPH who had negative results by CTPA and PA.

Objective To compare the blood flow characteristics of the proximal pulmonary arteries in patients with chronic thromboembolic pulmonary hypertension (CTEPH) and idiopathic pulmonary arterial hypertension (IPAH) by 3.0T PC-MRI. Methods Twenty seven patients with pulmonary arterial hypertension (7 IPAH patients and 20 CTEPH patients) were prospectively included. Twenty healthy volunteers were enrolled as the control group. All subjects underwent PC-MRI. PC-MRI derived parameters included peak, mean velocity and mean flow of main pulmonary artery (MPA), left/right pulmonary artery (LPA/RPA), left/right interlobar pulmonary artery (LIPA/RIPA). Right heart catheterization was performed in patients with pulmonary arterial hypertension. The parameters among CTEPH, IPAH group and control group were compared by one way analysis of variance. Results There were significant differences for peak velocity, mean velocity and mean flow among CTEPH, IPAH group and control group (F=4.13—102.81, all P<0.05). There was significant difference for peak velocity in RPA between CTEPH[(32.0 ± 7.8)cm/s] and IPAH group[(50.0±15.0)cm/s]. There was no difference for mean velocity between CTEPH and IPAH group. The mean flow between CTEPH and IPAH group was statistically different[MPA: (74.3 ± 20.8) ml/s versus (61.3±16.7) ml/s, LPA:(29.3±12.7) ml/s versus (23.2±11.2) ml/s, RPA:(43.5±17.4) ml/s versus (56.8±13.5) ml/s, LIPA: (19.2 ± 8.0) ml/s versus (12.1 ± 5.8) ml/s, all P<0.05]. Conclusion There is significantly different characteristics for the hemodynamics of the proximal pulmonary arteries between CTEPH group and IPAH group. 3.0T PC-MRI may effectively detect the pulmonary hemodynamic changes.

Objective To investigate the value of contrast enhancement T1 mapping in detection of diffuse myocardial fibrosis in cardiomyopathy, and the relationship between myocardial fibrosis and cardiac function. Methods From September 2013 to September 2014, 76 cases of cardiomyopathy patients (including myocarditis) and 33 cases of healthy controls were enrolled in our study. All the subjects underwent cardiac MR (CMR) examination. Scan sequences included cine MR, pre-contrast and post-contrast T1 mapping and late gadolinium enhancement (LGE) imaging. The pre-/post-contrast left ventricle average T1 value and cardiac function of patients and controls were measured and compared by using independent-samples t test. According to the LGE imaging, all the subjects were subsequently divided into LGE positive group, LGE negative group and control group. The myocardial average T1 value and cardiac function among the three sub-groups were compared by using one-way ANOVA, and the relationship among them were analyzed by using Pearson correlation. Results Among the 76 cases of non-ischemia cardiomyopathy patients, 51 cases (67.1%) had LGE. Compared with controls, cardiomyopathy patients presented with higher pre-contrast T1 value [(1 306.4 ± 84.6)ms vs. (1 266.6 ± 57.3)ms, t=2.10, P<0.05] and lower post-contrast T1 value [(483.6 ± 112.0)ms vs. (534.1 ± 92.7)ms,t=-0.27, P<0.05]. Pre-contrast and post-contrast average T1 value of LGE positive patients were (1 322.2 ± 85.8) and (459.7 ± 132.2)ms respectively;pre-contrast and post-contrast average T1 value of LGE negative patients were (1 267.0 ± 68.5) ms and (521.0±95.2)ms, there were statistical significant differences of T1 value between LGE positive and LGE negative patients (P<0.01), however, there were no statistical significant differences of T1 value between LGE negative patients and controls (P>0.05). There were correlation between pre-/post-contrast left ventricle T1 value and ejection fraction (EF) in cardiomyopathy patients (r=-0.252,-0.217, P<0.01), however no statistical correlation with other cardiac function parameters (P>0.05). Conclusions The average pre-/post-contrast T1 value in left ventricle myocardium are helpful for detection of diffuse fibrosis in cardiomyopathy patients. The LGE positive is a sign that can greatly change the T1 value of the myocardial tissue, meanwhile, myocardial fibrosis is negative correlated with ejection fraction in cardiomyopathy patients.

OBJECTIVE: To evaluate the effect of the vestibular diagnosis and treatment system (SRM-IV ) in diagnosis and treatment of patients with benign paroxysmal positional vertigo (BPPV). METHOD: Patients who were diagnosed as BPPV by SRM-TV in the clinic of our hospital from November 2013 to October 2014 were retrospectively analyzed in this study. RESULT: Among 425 suspected cases, 230 BPPV-positive patients were diagnosed including 131 cases of posterior SC (57.0%), 95 cases of horizontal SC (41.3%) and 4 cases of more than two SC (1.7%). The cure rate by SRM-V was 94.6% and the effective rate was 100.0%. The relapsed occurred in 10 patients (4.8%), which contained 4 men and 6 women. CONCLUSION SRM-V can realize 360° reasonable repositioning procedure while Canalish reposition procedure cannot. SRM-V can improve both the corrective rate of diagnosis and the cure rate, especially for the patients who suffered from complex BPPV.
Benign Paroxysmal Positional Vertigo ; diagnosis ; therapy ; Female ; Humans ; Male ; Patient Positioning ; Retrospective Studies ; Vestibule, Labyrinth ; physiopathology

Objective To explore the clinical application value of left atrial function with feature tracking cardiac magnetic resonance imaging (FT-CMR) by evaluating preliminarily left atrial strain and strain rate in patients with atrial fibrillation. Methods Thirty patients with paroxysmal atrial fibrillation, thirty patients with persistent atrial fibrillation and twenty-two healthy subjects were enrolled. All the subjects underwent cardiac magnetic resonance imaging with the real steady-state free precession(SSFP) sequence. FT-CMR parameters included left atrial strain and strain rate parameters, left atrial volume and function parameters were detected by using offline cardiovascular analysis software, respectively. Left atrial strain and strain rate parameters included left atrial total strain(Εs), passive strain(Εe), active strain(Εa), peak positive strain rate(SRs), peak early negative strain rate(SRe)and peak late negative strain rate(SRa). Volume and function parameters included maximum of left atrial volume(LAVmax), minimum of left atrial volume(LAVmin), total left atrial emptying fraction(LATEF), passive left atrial emptying fraction(LAPEF)and active left atrial emptying fraction(LAAEF). The differences in the general data among the paroxysmal atrial fibrillation group, the persistent atrial fibrillation group and the control group were compared by usingχ2 test or ANOVA analysis. The differences in all parameters between the atrial fibrillation group and the control group, the paroxysmal atrial fibrillation group and the persistent atrial fibrillation group were compared by using independent t test. Left atrial strain and strain rate parameters on an intra-observer and inter-observer were determined by intraclass correlation coefficient(ICC)analyses. Results Compared to control group, LAVmax and LAVmin in atrial fibrillation group were significantly increased(t=9.737,7.889,P<0.001);The LATEF and LAPEF had no significant difference, the LAAEF in two groups had statistically significant difference(t=-4.762,P<0.001).The absolute value of Es, Ee, Ea, SRs, SRe, SRa in atrial fibrillation group were significantly reduced than in control group(t=-7.732,-6.610,-6.493,-7.546, 6.864, 5.917,P<0.001). Compared with paroxysmal atrial fibrillation group, LAVmax and LAVmin in persistent atrial fibrillation group were increased obviously, LATEF and LAPEF were significantly decreased, and the differences were statistically significant(t=-4.575,-5.524, 4.002, 4.028,P<0.001).The LAAEF in two groups had no statistically significant difference. Compared with strain and strain rate in two groups, absolute value of Es, Ee, Ea, SRs, SRe, SRa in persistent atrial fibrillation group significantly decreased than in paroxysmal atrial fibrillation(t=4.310, 3.128, 4.465, 5.496,-3.290,-3.863,P<0.001). The intra-group and inter-group had well correlation coefficients between the observers in the left atrial strain and strain rate parameters of the subjects(ICC=0.85—0.94,0.81—0.90). Conclusions FT-CMR technique can be used to assess the left atrial strain and strain rate in patients with atrial fibrillation;Left atrial reservoir, conduit and booster-pump functions in patients with atrial fibrillation were impaired. Patients with persistent atrial fibrillation had worse left atrial function throughout the entire cardiac cycle compared with those with paroxysmal atrial fibrillation.

Objective:To explore the relationship between the imaging features of enhanced MRI in patients with central chronic pulmonary artery thromboembolism (CPTE) and pulmonary vascular resistance (PVR).Methods:Thirty-nine patients with CPTE who had contrast-enhanced MRI examination were retrospectively enrolled this study from January 2018 to December 2020. And 33 patients who received right heart catheterization were divided into two groups based on PVR=1 000 dyn·s·cm -5. The differences of imaging features of CPTE in enhanced MRI between the two groups were compared. The relationship between gender, duration of disease, age, pleural thickening, bilateral bronchial artery dilation, number of the involved vascular segments, number of thrombosis, number of the thrombus-related delayed enhancement of artery wall and PVR was analyzed by binary logistic regression. Results:In 39 patients with central CPTE, the dilated lumen (168, 43.30%) and delayed enhancement of wall (122, 31.52%) were found in most of pulmonary arteries. The rate of the lumen dilatation associated with thrombus was the highest among that of the lumen abnormality (66, 52.80%). There were more thrombi in PVR<1 000 dyn·s·cm -5 group than those in PVR≥1 000 dyn·s·cm -5 group (χ 2=9.55, P=0.002). There was no significant difference in the incidence of wall delayed enhancement associated the thrombus between the two groups (χ 2=0.90, P=0.344). The incidence of bilateral bronchial arterial dilatation in PVR<1 000 dyn·s·cm -5 group was higher than that in PVR≥1 000 dyn·s·cm -5 group ( P=0.019). Logistic regression analysis showed that female, the less number of involved vascular segments and bilateral bronchial artery dilation were correlated with the lower PVR. Conclusions:Enhanced MRI is helpful to accurately evaluate the lumen abnormality of pulmonary artery and wall remodeling in central CPTE, which is of great value for the assessment of patients′ conditions and treatment effect.

Objective To observe the value of optimized temporal parallel acquisition technique (TPAT) sequence in evaluating cardiac structure and function in arrhythmia patients.Methods Totally 33 arrhythmia patients (arrhythmia group) and 48 normal rhythm subjects (normal group) underwent cardiac MRI with conventional cine (balanced steadystate free-precession [bSSFP]) sequence and optimized TPAT sequence.Myocardial thickness,cardiac function,myocardial strain parameters of left ventricle and image quality of 2 sequences were compared in the two groups,respectively.Results In arrhythmia group,there was statistical difference of myocardial thickness in 12 myocardial segments between the 2 sequences (all P ＜ 0.05),as well as peak and average values of myocardial radial and circumferential strain (all P＜0.05).In normal group,there was no statistical difference of myocardial thickness and stain parameters between the 2 sequences (all P＞0.05).Additionally,no statistical difference of cardiac function was found between the 2 sequences in two groups (all P＞0.05).In arrhythmia group,the image quality of optimized TPAT sequence was better than that of bSSFP sequence (P＜0.05).Conclusion For arrhythmia patients,optimized TPAT cine sequence could improve image quality of cardiac MRI.

Objective To analyze differential metabolites (DMs) in the urine of workers with occupational nickel exposure using non-targeted metabolomics, and to screen differential metabolic pathways. Methods A total of 30 nickel exposed workers were selected as the exposure group, and 30 administrative staff from the same factory were selected as the control group using the judgment sampling method. Urine samples of the individuals from the two groups were collected. The ultra-high performance liquid chromatography with quadrupole time-of-flight mass spectrometry and non-targeted metabolomics were used to detect and identify metabolites. The differential metabolic profiles were compared between workers of the two groups, and key differential metabolic pathways and potential biomarkers were screened. The association of DMs and urinary nickel level were evaluated by Spearman correlation coefficients. The sensitivity and specificity of biomarkers were assessed by receiver operating characteristic (ROC) curve analysis. Results A total of 418 metabolites were identified in the urine of worker in the exposure and control groups. The result of principal component analysis and orthogonal partial least squares analysis showed that there were 128 DMs in the urine of workers in the exposure group compared with the control group. These DMs were mainly enriched in glutathione metabolism, carnitine synthesis, and amino acid and nucleotide metabolism pathways, including glycine and serine metabolism. The result of correlation analysis and ROC curve analysis revealed that 4-methylcatechol, 4-vinylphenol sulfate, 2-hydroxyphenylacetone sulfate, 2-dodecylbenzenesulfonic acid, and decylbenzenesulfonic acid could be the potential biomarkers for nickel exposure (all area under the ROC curve >0.800). Conclusion There were significant differences in the urinary metabolic profiles of workers with occupational nickel exposure. The five DMs including 4-methylcatechol, 4-vinylphenol sulfate, 2-hydroxyphenylacetone sulfate, 2-dodecylbenzenesulfonic acid, and decylbenzenesulfonic acid. These DMs could be potential biomarkers of occupational nickel exposure.

Biotoxins, which include bacterial, fungal, marine, plant, and animal toxins, are widespread in living and occupational environments, posing potential threats to human health. Rapid detection of biotoxins in blood is crucial for preventing health hazards and enabling timely disease diagnosis and treatment. Biosensors and immunoassay technologies have critical advantages in the rapid detection of biotoxins in blood. Common biosensors, such as surface plasmon resonance biosensors and fluorescent biosensors, enhance sensitivity and reduce detection limits through signal amplification. Common immunoassay methods, such as colloidal gold immunochromatography, fluorescence immunochromatography, and chemiluminescence immunoassay, improve detection efficacy and sensitivity through specific antibody-antigen binding and nanotechnology. However, current rapid detection technologies of bitoxins in blood face challenges such as matrix interference and insufficient specificity, and they fall short in high-throughput detection of multiple toxins simultaneously. Future developments should focus on improving sample pretreatment, innovating signal amplification methods, enhancing specificity on recognition of elements, and designing portable detection devices and high-throughput platforms for simultaneous toxin analysis. These advancements aim to improve the sensitivity and reliability of detection methods, providing more accurate and convenient solutions for biotoxin detection in blood.

Objective:To analyze the late gadolinium enhancement (LGE) manifestations, cardiac function, and myocardial strain by feature tracking (FT) in Takayasu arteritis (TA) with pulmonary artery involvement (PTA) using cardiac MR (CMR), and then to investigate manifestations of the impaired myocardial structure and function.Methods:A retrospective study was performed on 32 patients with PTA and 21 healthy subjects without cardiopulmonary diseases from January 2017 to December 2020. All of them underwent CMR examinations. According to the presence of pulmonary arterial hypertension (PAH),PTA patients were divided into two groups including PAH group (11 cases) and non-PAH group (21 cases). LGE manifestations were observed and Fisher exact test was used for statistical analysis between the two groups. Cardiac function parameters and FT values including global peak strain of the left and right ventricle were calculated separately in PAH, non-PAH group of patients and healthy controls, using One-way ANOVA or non-parametric Kruskal-Wallis test for statistical analysis including a pairwise comparison between groups. The correlations between FT values of the PAH group and parameters measured by right heart catheterization test (RHC) and transthoracic echocardiography were analyzed using Pearson or Spearman correlation analysis.Results:There were 23 PTA patients (71.9%) with LGE. LGE in the interventricular insertion points (IPs)(11/11), and in the mid-wall (11/11) or epicardial (10/11) myocardium was more common ( P values were 0.006,<0.001 and 0.011, respectively) in PAH group, compared with LGE in the IPs (11/21), and in the mid-wall (7/21) or epicardial (9/21) myocardium in non-PAH group. The absolute values of left ventricular global peak circumferential strain (LVGPCS), left ventricular global peak longitudinal strain (LVGPLS) and right ventricular global peak longitudinal strain in PAH group were smaller than those in healthy subjects ( P<0.05). The absolute values of LVGPCS and LVGPLS in non-PAH group were smaller than those in healthy subjects ( P<0.05). In PAH group, mean pulmonary artery pressure of RHC was correlated with several FT parameters ( P<0.05), especially left ventricular global peak radial strain ( r=-0.807, P=0.009) and LVGPCS ( r s=0.817, P=0.007). Conclusions:Myocardial injury can be seen in PTA patients. And LGE in the IPs and LGE in the mid-wall or epicardial myocardium is more common in PTA patients with PAH. LVGPCS and LVGPLS can early indicate left heart dysfunction in PTA patients without PAH.