RESUMO
Objective:To investigate the application value of WeChat-based problem-based learning teaching method combined with micro-classroom in the teaching of contrast-enhanced gastrointestinal ultrasound imaging for residents in standardized residency training.Methods:A total of 40 trainees who underwent the standardized residency training in the Department of Ultrasound, The First Affiliated Hospital of Chongqing Medical University from January 2019 to June 2021 were selected as the research objects. They were randomly divided into the experimental group (WeChat-based PBL teaching method combined with micro-classroom) and the control group (traditional teaching method). The teaching content was the diagnosis of gastrointestinal ultrasound imaging. After the theoretical learning and practice, assessments of contrast-enhanced gastrointestinal ultrasound imaging including theory and operating practice were performed to all students. SPSS 22.0 was used for t test and rank sum test.Results:After training, the theoretical test scores of the experimental group were higher than those of the control group [(93.09±2.31) vs. (90.63±2.26)], and the difference was statistically significant ( P<0.05). However, there was no significant difference between the two groups in the number distribution of students at all levels of operational practice ( P>0.05). Conclusion:The WeChat-based PBL teaching method combined with micro-classroom is beneficial to improve students' knowledge of contrast-enhanced gastrointestinal ultrasound imaging, and is worth being popularized and applied in clinical teaching.
RESUMO
Objective To investigate regional ventricular long-axis velocity and adjacent intraventricular flow velocity using dual-pulse wave(PW) Doppler echocardiography synchronously,and to analyze the coupling relationship between regional ventricular long-axis strain and adjacent intraventricular pressure gradients in normal cases using dual-PW Doppler echocardiography.Methods Eighty-six normal subjects aged 19～66 years [mean age (37.49 ± 11.97)years] underwent routine echocardiography and dualPW Doppler echocardiographic exam.Total 18 segments were sampled using dual-PW Doppler (PW/TDI mode) images at basal,mid and apical levels on three standard apical views,and electrocardiogram was recorded simultaneously.Peak early diastolic velocity (emax),peak late diastolic velocity (amax),peak early mitral diastolic inflow velocity (Emax),regional peak early diastolic velocity (Em),regional peak late diastolic velocity (Am) and regional peak early diastolic inflow velocity (E) were measured simultaneously in the same one cardiac cycle.Myocardial variations of left ventricular segments were observed.Em,Am and E of different levels from different ventricular wall were analyzed.The co-relationship between regional ventricular long-axis strain and adjacent intraventricular pressure gradients were calculated and analyzed.Results ①Regional myocardial velocity and regional peak early diastolic inflow velocity in normal subjects declined from basal to apical segments gradually at the same ventricular wall (P ＜ 0.01).② Emax was correlated with emax(r =0.418,P ＜0.001),and E was correlated with Em (posterior septum,r =0.610,P ＜0.001 ；anterior wall,r =0.499,P ＜0.001).③There was a medium correlation between normal longaxis strain in segments and adjacent intraventricular pressure gradients (the global,r =0.412,P ＜0.001 ；posterior septum,r =0.319,P ＜0.005).Conclusions The acquirement of E and Em by dual-PW Doppler showed downtrend of segmental wall movement and regional blood flow from basal segment to apex.Emax is correlated with e E is correlated with Em,and long-axis strain at segments is correlated with adjacent intraventricular pressure gradients partly.Dual-PW Doppler might provide a potential method for the more precise evaluation of left ventricular fluid-solid coupling during diastole.