Electrical impedance tomography (EIT) is a new non-invasive functional imaging technology, which has the advantages of non-invasion, non-radiation, low cost, fast response, portability and visualization. In recent years, more and more studies have shown that EIT has great potential in the detection of lung diseases and has been applied to early diagnosis and treatment of some diseases. This paper introduced the basic principle of EIT, discussed the research and clinical application of EIT in the detection of acute respiratory distress syndrome, chronic obstructive pulmonary disease, pneumothorax and pulmonary embolism, and focused on the summary and introduction of indicators and functional images of EIT related to the detection of lung diseases. This review will help medical workers understand and use EIT, and promote the further development of EIT in lung diseases as well as other fields.
Humans ; Electric Impedance ; Tomography/methods* ; Lung Diseases/diagnosis* ; Pulmonary Disease, Chronic Obstructive/diagnosis* ; Pulmonary Embolism/diagnosis* ; Respiratory Distress Syndrome/diagnosis*

Objective:To evaluate left atrial(LA) function and its value in predicting left ventricular(LV) remodeling in patients with coronary heart disease (CHD) by four dimensional automatic left atrial quantitation (4D Auto LAQ).Methods:A total of 176 patients with CHD were prospectively enrolled in Fuwai Central China Cardiovascular Hospital from October 2021 to September 2022. They were divided into two groups according to left ventricular mass index: LV remodeling group (female>95 g/m 2, male>115 g/m 2, n=88) and Non-LV remodeling group (female≤95 g/m 2, male≤115 g/m 2, n=88). The 3D dynamic image of LA was analyzed by 4D Auto LAQ on machine to obtain the LA parameters, including the minimum, maximum, pre-systolic and emptying volumes of LA (LAVmin, LAVmax, LAVpreA, LAEV), LA ejection fraction (LAEF), LA reservoir longitudinal and circumferential strains (LASr, LASr-c), LA conduit longitudinal and circumferential strains (LAScd, LAScd-c) and LA contraction longitudinal and circumferential strains (LASct, LASct-c). Logistic regression models were used to analyze the value of LA parameters in predicting LV remodeling in patients with CHD. ROC curve was used to evaluate LA parameters and left atrial volume index (LAVI) to predict the diagnostic efficiency of LV remodeling. Results:Compared with the Non-LV remodeling group, LAVmin, LAVmax, LAVpreA were significantly increased and LAEF, LASr, LAScd, LASct, LASr-c, LAScd-c, LASct-c were significantly decreased in the LV remodeling group ( P<0.05). Logistic regression model showed that LASct-c was an independent risk factor for LV remodeling in patients with CHD after adjustment( OR=2.018, 95% CI=1.214-3.355). ROC curve analysis showed that the area under the curve of LASct-c for predicting LV remodeling in CHD patients was 0.844, the sensitivity was 0.784, and the specificity was 0.761. Conclusions:4D Auto LAQ can effectively evaluate LA function in patients with CHD.LASct-c can be used as a reference index to predict LV remodeling in patients with CHD, which provides a new evaluation method in prognosis evaluation of CHD patients.

Objective:To analyze the left atrial (LA) function and predict the value of diastolic dysfunction (LVDD) in patients with heart failure (HF) by four-dimensional automatic left atrial quantitation (4D Auto LAQ) technology.Methods:A total of 90 patients with HF(LVDD group) and 30 healthy volunteers (control group)were enrolled from January 2021 to July 2021 in Fuwai Central China Cardiovascular Hospital. The patients with HF were divided into 3 groups according to the degree of LVDD: grade Ⅰ( n=30), grade Ⅱ( n=30), grade Ⅲ( n=30). Four-dimensional dynamic images of LA were collected by 4D Auto LAQ technology for on-machine analysis. LA volume and strain parameters were obtained, including LA maximum volume index (LAVImax), LA reservoir longitudinal and circumferential strains (LASr, LASr-c), LA conduit longitudinal and circumferential strains (LAScd, LAScd-c) and LA contraction longitudinal and circumferential strains (LASct, LASct-c). Pearson linear correlation was used to analyze the correlation between LA strain parameters and diastolic function parameters (LAVImax, E/A, E/e′) in HF patients. ROC curves were plotted to analyze the diagnostic performance of LA strain parameters and LAVImax for grade Ⅲ LVDD, the area under the curve (AUC) was calculated and pairwise comparisons were made. Results:①Compared with the control group, LAVmin, LAVpreA, LAScd, LASct, LAScd-c, and LASct-c were increased, and LASr, and LASr-c were decreased in the grade Ⅰ, Ⅱ, and Ⅲ LVDD groups (all P<0.05). LAVmin, LAVpreA, LAVmax, LAVImax, LAScd, LASct, LAScd-c and LASct-c were increased, and LASr and LASr-c were decreased in grade Ⅲ LVDD group compared with grade Ⅰ and Ⅱ LVDD groups (all P<0.05). ②Pearson correlation analysis showed that LASr, LASct, LASr-c and LASct-c were strongly correlated with diastolic function parameters (LAVImax, E/A, E/e′) (all P<0.01). ③ROC curve analysis showed that LASr-c had significantly better performance (AUC 0.868, sensitivity 96.7%, specificity 66.7%) than other parameters in the diagnosis of grade Ⅲ LVDD. Conclusions:4D Auto LAQ can effectively evaluate the LA volume and function in patients with HF. LASr-c is optimal in predicting grade Ⅲ LVDD, 4D Auto LAQ provides a new reference for evaluating diastolic function in patients with HF.

Objective:To evaluate the distribution of diastolic left ventricular pressure in patients with type 2 diabetes mellitus (T2DM) by relative pressure imaging (RPI) based on vector flow mapping (VFM), and to explore the clinical risk factors for the diastolic left ventricular pressure distribution.Methods:Thirty patients with T2DM and thirty normal controls were included from August 2020 to July 2021 in Fuwai Central China Cardiovascular Hospital. All selected subjects underwent conventional echocardiography.Left intraventricular pressure difference (IVPD) and left intraventricular pressure gradient (IVPG) were measured using RPI of VFM in isovolumic relaxation (IR), rapid filling (RF), atrial contraction (AC), isovolumic contraction (IC) and rapid ejection (RE) phases. The relationships between IVPD with other parameters were analyzed.Results:①Compared with the control group, E/A, e′, IVPD-IR, IVPG-IR, IVPD-RF, IVPG-RF, IVPD-AC, and IVPG-AC were significantly lower and E/e′ was significantly greater in the T2DM group ( P<0.05). ②IVPD-IR, IVPD-RF, and IVPD-AC were positively correlated with E/A ( r=0.309, P<0.05; r=0.274, P<0.05; r=0.273, P<0.05). IVPD-IR, IVPD-RF, and IVPD-AC were negatively correlated with E/e′ ( r=-0.587, P<0.05; r=-0.273, P<0.05; r=-0.415, P<0.05). IVPD-IR and IVPD-AC were positively correlated with e′ ( r=0.451, P<0.05; r=0.431, P<0.05). ③Multivariable linear regression analysis showed that hemoglobin A 1c (HbA 1c) was an independent risk factor affecting IVPD-IR, IVPD-RF, and IVPD-AC (β=-0.417, P<0.05; β=-0.451, P<0.05; β=-0.460, P<0.05). Conclusions:RPI of VFM can quantitatively evaluate diastolic left ventricular pressure distribution in patients with T2DM. HbA 1c is an independent risk factor affecting IVPD-IR, IVPD-RF, and IVPD-AC.

Objective:To investigate the associations of articular depression depth (ADD) and tibial plateau widening (TPW) by pre-operative CT measurement with incidence of lateral meniscal tear in patients with Schatzker type Ⅱ tibial plateau fracture.Methods:Included in this retrospective study were 131 patients who had been admitted to Emergency Center of Trauma, The Third Hospital Affiliated to Hebei Medical University from January 2016 to January 2020 for Schatzker type Ⅱtibial plateau fractures. They were 88 males and 51 females, aged from 18 to 60 years (average, 41.5 years), with 74 right and 57 left sides injured. All patients were treated with closed reduction and internal fixation assisted by bidirectional traction. Arthroscopy was used to detect the status of lateral meniscus immediately after closed reduction and internal fixation of the fracture fragments. Furthermore, patients were divided into 2 groups according to the integrity of lateral meniscus: meniscal tear group ( n=70) and tear-free group ( n=61). The 2 groups were compared in terms of age, gender, body mass index(BMI), injury side, time interval from injury to surgery, TPW and ADD. The receiver operating curve (ROC) was drafted to calculate the cut-off values of TPW and ADD in complication of lateral meniscal tear in patients with Schatzker type Ⅱ tibial plateau fracture. Results:The overall incidence of lateral meniscal tear in this cohort was 53.4% (70/131). There was no statistically significant difference in terms of age, gender, injury side, BMI or time interval from injury to surgery between the 2 groups ( P>0.05); TPW and ADD were significantly higher in the meniscal tear group than in the tear-free group ( P<0.05). To predict lateral meniscal tear in patients with Schatzker type Ⅱtibial plateau fracture, the area under ROC was 0.656 (95% CI: 0.562 to 0.750, P=0.002) for TPW and 0.709 (95% CI: 0.619 to 0.800, P<0.001) for ADD, respectively; the cut-off values of TPW and ADD were 4.3 mm and 6.1 mm. Conclusion:TPW and ADD may be effective predictors for prediction of lateral meniscal tear in patients with Schatzker type Ⅱ tibial plateau fracture.

Developing tumor-specific drug delivery systems with minimized off-target cargo leakage remains an enduring challenge. In this study, inspired from the natural cryptobiosis explored by certain organisms and stimuli-responsive polyphenol‒metal coordination chemistry, doxorubicin (DOX)-conjugated gelatin nanoparticles with protective shells formed by complex of tannic acid and Fe

Objective:To quantitatively evaluate the global myocardial work of left ventricle in patients with chronic kidney disease (CKD) by left ventricular pressure-strain loops (PSL).Methods:Forty patients with chronic kidney disease (CKD) in Henan Provincial People′s Hospital from February 2019 to October 2019 were chosen as case group.According to the decreased level of the glomerular filtration rate (GFR), CKD patients were divided into CKD 2-3 stage group( n=20) and CKD 4-5 stage group( n=20), and 20 healthy volunteers were selected as control group.The working parameters of the global left ventricular myocardium including the global work index (GWI), the global constructive work (GCW), the global wasted work (GWW), the global work efficiency (GWE) were measured by the left ventricular PSL, and the differences of the parameters among the three groups were compared. Results:Compared with the control group, the GWI, GCW, GWW in the CKD 2-3 stage group and CKD 4-5 group were significantly higher and the GWE was lower than those in the control group differences were all (all P<0.05). Compared with the CKD 2-3 stage group, the GWI and GCW of the CKD 4-5 stage group were increased (all P<0.05), but there were no significant differences in GWW and GWE ( P>0.05). Conclusions:Left ventricular PSL provides a new method for evaluating the changes of left ventricular systolic function in patients with CKD.

Objective: To explore the application value of pressure-strain loop (PSL) in evaluating left ventricular myocardial work (MW) in patients with chronic heart failure (CHF). Methods: Seventy patients with CHF were selected as case group(CHF group) and were divided into 2 groups according to the left ventricular ejection fraction (LVEF) in ultrasonic cardiogram: LVEF preserve group (HFpEF group, LVEF≥50%, n=35) and LVEF reduced group (HFrEF group, LVEF<50%, n=35). Thirty-three healthy volunteers were selected as control group at the same period. Two-dimensional dynamic images in apical two chamber, three chamber and four chamber views were collected by two-dimensional speckle-tracking. Using the off-line EchoPAC software, a tracing analysis was conducted and the blood pressure was entered to obtain left ventricular global longitudinal strain (GLS), global MW index (GWI), global constructive work (GCW), global wasted work (GWW) and MW efficiency (GWE). The differences of GLS and MW parameters (GWI, GCW, GWW, GWE) were compared between each groups, and Pearson correlation was used to analyze the correlation between MW parameters and LVEF. Results: Compared with the control group and HFpEF group, the left atrial dimension(LAD), left ventricular end-diastolic dimension(LVDd), left ventricular end-diastolic volume(LVEDV), left ventricular end-systolic volume(LVESV) in HFrEF group increased, while LVEF decreased significantly(P<0.05). Compared with the control group, LAD in HFpEF group increased, the vaules of GLS, GWI, GCW were obviously lower in HFpEF group and HFrEF group(all P<0.05), GWW was higher and GWE was lower in HFrEF group(all P<0.05). GLS, GWI, GCW, GWE decreased and GWW increased in HFrEF group than those in HFpEF group, and all the differences were statistically significant(all P<0.05). In CHF group, GWW was negatively correlated with LVEF (r=-0.521, P<0.001) while positive correlations between GWI, GCW, GWE and LVEF were discovered (r=0.846, 0.807, 0.788; all P<0.001). Conclusions PSL can effectively evaluate the left ventricular MW in CHF patients. It has a certain correlation with LVEF and can reflect left ventricular systolic function. It provides a new reference index for the clinical diagnosis and evaluation of prognosis in CHF patients.

In December 2019, the corona virus disease 2019 (COVID-19) broke out in Wuhan, Hubei Province. Although the number of newly confirmed COVID-19 cases in provinces outside of Hubei Province has declined continuously since February 4, the epidemic of COVID-19 remains serious. As companies resume work, it is still inevitable that some high-energy orthopedic trauma patients and elderly patients with low-energy fractures will need surgical treatment. The operating room, as a place for close contact between doctors, patients and nurses, increases the risk of infection and transmission. Based on the current needs of orthopedic trauma patients and the situation of the country's resistance to the epidemic of COVID-19, the authors expound the operating room management, preparation of medical materials, transfer of patients needing surgery, intraoperative protection and post-operative end disinfection in Third Hospital of Hebei Medical University so as to provide reference for prevention and control management of the operating room during the epidemic period.

Objective To investigate the clinical application value of longitudinal peak strain( LPS ) and peak strain dispersion ( PSD ) in evaluating left ventricular systolic function and synchrony in patients with essential hypertension . Methods Fifty‐five patients with essential hypertension were enrolled , including 30 patients with non‐left ventricular hypertrophy ( NLV H ) , 25 patients with left ventricular hypertrophy ( LV H ) , at the same time , 30 healthy volunteers were selected as the control group . Echocardiography was performed in all three groups ,and two‐dimensional dynamic images of the left ventricular apical four‐chamber ,three‐chamber ,and two‐chamber′s long‐axis view s were collected for three consecutive cardiac cycles . T he myocardial layer‐specific strain was used to measure the LPS of the left ventricular myocardium of subendocardium ,the middle layer ,the subepicardium ,and the myocardial strain and the PSD of the w hole myocardial layers . Correlation analysis and ROC curve analysis were performed . Results T he LPS in the control group ,NLV H group and LV H group were decreased in turn from inner to out myocardial layers . Compared with the control group , the LPS in the subendocardial , middle , subepicardial ,and w hole myocardial layer of NLV H group were decreased ( P ＜ 0 .05 ) , and the subepicardial myocardial LPS was slightly lower than that in the control group ,the difference was not statistically significant ( P ＞ 0 .05 ) . T he LPS in the subendocardial , middle , subepicardial ,and whole myocardial layer of LV H group were all reduced ( P＜0 .05) . Between the NLV H group and LV H group , the declines of the LPS in the subendocardial and middle layer in the LV H group were statistically significant ( P ＜0 .05) ,the LPS in the subepicardial layer and the w hole myocardial layer had no significant difference ( P ＞0 .05) . Compared with the control group ,the PSD of the NLVH group and the LVH group increased ( P ＜ 0 .05 ) . Compared with the NLV H group ,the PSD of the LV H group increased ( P ＜0 .05) . Inter‐ventricular septum thickness ( IVSd) and the LPS in the subendocardial ,middle ,subepicardial , and w hole myocardial layer were negatively correlated ( r ＝ －0 .537 ,－0 .518 ,－0 .266 ,－0 .471 ; all P ＜0 .05) , left ventricle posterior wall thickness ( LVPWd ) and the LPS in the subendocardial , middle , subepicardial ,and whole myocardial layer were negatively correlated ( r ＝ －0 .539 , －0 .524 , －0 .283 ,－0 .478 ;all P ＜0 .05) . T he area under the ROC curve ( AUC) of the LPS in the subendocardial ,middle , subepicardial ,and w hole myocardial layer and PSD for the diagnosis of hypertension were 0 .685 ,0 .652 , 0 .510 ,0 .623 ,0 .995 ,respectively . T he cut‐off values were －21 .70% ,－18 .90% ,－16 .95% ,－19 .45% , 46 .50 ms , and the sensitivities were 94 .4% , 83 .3% , 77 .8% , 94 .4% , 100% , respectively , and the specificities were 47 .8% ,52 .2% ,39 .1% ,39 .1% ,95 .7% ,respectively . Conclusions T he layer‐specific strain can quantitatively evaluate myocardial longitudinal strain in patients with essential hypertension , provide a non‐invasive test for early diagnosis of hypertensive heart disease ,and the evaluation of left ventricular myocardial stratification . PSD for evaluating primary synchronous changes in left ventricular myocardial contraction in patients with hypertension has certain advantages .