Microvascular ultrasound (US) techniques are advanced Doppler techniques that provide high sensitivity and spatial resolution for detailed visualization of low-flow vessels. Microvascular US imaging can be applied to breast lesion evaluation with or without US contrast agents. Microvascular US imaging without a contrast agent uses a sophisticated wall filtering system to selectively obtain low-flow Doppler signals from overlapped artifacts. Microvascular US imaging with secondgeneration contrast agents amplifies flow signals and makes them last longer, which facilitates hemodynamic evaluation of breast lesions. In this review article, we will introduce various microvascular US techniques, explain their clinical applications in breast cancer diagnosis and radiologic-histopathologic correlation, and provide a summary of a recent radiogenomic study using microvascular US.

Microvascular ultrasound (US) techniques are advanced Doppler techniques that provide high sensitivity and spatial resolution for detailed visualization of low-flow vessels. Microvascular US imaging can be applied to breast lesion evaluation with or without US contrast agents. Microvascular US imaging without a contrast agent uses a sophisticated wall filtering system to selectively obtain low-flow Doppler signals from overlapped artifacts. Microvascular US imaging with secondgeneration contrast agents amplifies flow signals and makes them last longer, which facilitates hemodynamic evaluation of breast lesions. In this review article, we will introduce various microvascular US techniques, explain their clinical applications in breast cancer diagnosis and radiologic-histopathologic correlation, and provide a summary of a recent radiogenomic study using microvascular US.

BACKGROUND: Statistical analysis is essential in regard to obtaining objective reliability for medical research. However, medical researchers do not have enough statistical knowledge to properly analyze their study data. To help understand and potentially alleviate this problem, we have analyzed the statistical methods and errors of articles published in the Korean Journal of Pain (KJP), with the intention to improve the statistical quality of the journal. METHODS: All the articles, except case reports and editorials, published from 2004 to 2008 in the KJP were reviewed. The types of applied statistical methods and errors in the articles were evaluated. RESULTS: One hundred and thirty-nine original articles were reviewed. Inferential statistics and descriptive statistics were used in 119 papers and 20 papers, respectively. Only 20.9% of the papers were free from statistical errors. The most commonly adopted statistical method was the t-test (21.0%) followed by the chi-square test (15.9%). Errors of omission were encountered 101 times in 70 papers. Among the errors of omission, "no statistics used even though statistical methods were required" was the most common (40.6%). The errors of commission were encountered 165 times in 86 papers, among which "parametric inference for nonparametric data" was the most common (33.9%). CONCLUSION: We found various types of statistical errors in the articles published in the KJP. This suggests that meticulous attention should be given not only in the applying statistical procedures but also in the reviewing process to improve the value of the article.
Intention

Background: Although cardiovascular outcome trials using sodium-glucose cotransporter-2 inhibitors (SGLT-2i) showed a reduction in risk of 3-point major adverse cardiovascular events (MACE), they did not demonstrate beneficial effects on stroke risk. Additionally, meta-analysis showed SGLT-2i potentially had an adverse effect on stroke risk. Contrarily, pioglitazone, a type of thiazolidinedione (TZD), has been shown to reduce recurrent stroke risk. Thus, we aimed to compare the effect of SGLT-2i and TZD on the risk of stroke in type 2 diabetes mellitus (T2DM) patients. Methods: Using the Korean National Health Insurance Service data, we compared a 1:1 propensity score-matched cohort of patients who used SGLT-2i or TZD from January 2014 to December 2018. The primary outcome was stroke. The secondary outcomes were myocardial infarction (MI), cardiovascular death, 3-point MACE, and heart failure (HF). Results: After propensity-matching, each group included 56,794 patients. Baseline characteristics were well balanced. During the follow-up, 862 patients were newly hospitalized for stroke. The incidence rate of stroke was 4.11 and 4.22 per 1,000 person-years for the TZD and SGLT-2i groups respectively. The hazard ratio (HR) of stroke was 1.054 (95% confidence interval [CI], 0.904 to 1.229) in the SGLT-2i group compared to the TZD group. There was no difference in the risk of MI, cardiovascular death, 3-point MACE between groups. Hospitalization for HF was significantly decreased in SGLT-2i-treated patients (HR, 0.645; 95% CI, 0.466 to 0.893). Results were consistent regardless of prior cardiovascular disease. Conclusion In this real-world data, the risk of stroke was comparable in T2DM patients treated with SGLT-2i or TZD.

Selective termination can be used to preserve normal fetus from the other fetus with chromosomal, structural abnormality in multifetal pregnancy. This case is about twin pregnant patient who had undergone in vitro fertilization and embryo transfer. In 18 weeks of gestation, we found that one of the fetus had cranical encephalocele and was in concern for the termination by using ultrasound guided intrcardiac injection of 2.5 ml of potassium chloride solution. After performing this procedure the other healthy female newborn was naturally delivered at 38 weeks gestation with weight of 2.8 kg.
Embryo Transfer* ; Embryonic Structures* ; Encephalocele* ; Female ; Fertilization in Vitro* ; Fetus ; Humans ; Infant, Newborn ; Potassium Chloride ; Pregnancy ; Pregnancy Trimester, Second* ; Pregnancy* ; Pregnancy, Twin ; Twins, Dizygotic* ; Ultrasonography

Background: Diabetic kidney disease (DKD) is a risk factor for hospitalization for heart failure (HHF). DKD could be classified into four phenotypes by estimated glomerular filtration rate (eGFR, normal vs. low) and proteinuria (PU, negative vs. positive). Also, the phenotype often changes dynamically. This study examined HHF risk according to the DKD phenotype changes across 2-year assessments. Methods: The study included 1,343,116 patients with type 2 diabetes mellitus (T2DM) from the Korean National Health Insurance Service database after excluding a very high-risk phenotype (eGFR <30 mL/min/1.73 m2) at baseline, who underwent two cycles of medical checkups between 2009 and 2014. From the baseline and 2-year eGFR and PU results, participants were divided into 10 DKD phenotypic change categories. Results: During an average of 6.5 years of follow-up, 7,874 subjects developed HHF. The cumulative incidence of HHF from index date was highest in the eGFRlowPU– phenotype, followed by eGFRnorPU+ and eGFRnorPU–. Changes in DKD phenotype differently affect HHF risk. When the persistent eGFRnorPU– category was the reference, hazard ratios for HHF were 3.10 (95% confidence interval [CI], 2.73 to 3.52) in persistent eGFRnorPU+ and 1.86 (95% CI, 1.73 to 1.99) in persistent eGFRlowPU–. Among altered phenotypes, the category converted to eGFRlowPU+ showed the highest risk. In the normal eGFR category at the second examination, those who converted from PU– to PU+ showed a higher risk of HHF than those who converted from PU+ to PU–. Conclusion Changes in DKD phenotype, particularly with the presence of PU, are more likely to reflect the risk of HHF, compared with DKD phenotype based on a single time point in patients with T2DM.

Background: Diabetic kidney disease (DKD) is associated with an elevated risk of fractures. However, little is known about the association between proteinuric or non-proteinuric DKD and the risk of hip fracture. Thus, we investigated the incidence of hip fractures among Korean adults with type 2 diabetes mellitus (T2DM) stratified by DKD phenotype. Methods: In this retrospective cohort study using the Korean National Health Insurance Service database, patients with T2DM who received at least one general health checkup between 2009 and 2012 were followed until the date of hip fracture, death, or December 31, 2018. We classified the DKD phenotype by proteinuria and estimated glomerular filtration rate (eGFR), as follows: no DKD (PU−GFR−), proteinuric DKD with normal eGFR (PU+GFR−), non-proteinuric DKD with reduced eGFR (PU−GFR+), and proteinuric DKD with reduced eGFR (PU+GFR+) Results: The cumulative incidence of hip fractures was highest in the PU+GFR+ group, followed by the PU−GFR+ group and the PU+GFR− group. After adjustment for confounding factors, the hazard ratio (HR) for hip fracture was still highest in the PU+GFR+ group. However, the PU+GFR− group had a higher HR for hip fracture than the PU−GFR+ group (PU+GFR+ : HR, 1.69; 95% confidence interval [CI], 1.57 to 1.81; PU+GFR− : HR, 1.37; 95% CI, 1.30 to 1.46; PU−GFR+ : HR, 1.20; 95% CI, 1.16 to 1.24 using the PU−GFR− group as the reference category). Conclusion The present study demonstrated that DKD was significantly associated with a higher risk of hip fracture, with proteinuria as a major determinant.

PURPOSE: This study was done to identify whether pre-conditioning exercise has neuroprotective effects against cerebral ischemia, through enhance brain microvascular integrity. METHODS: Adult male Sprague-Dawley rats were randomly divided into four groups: 1) Normal (n=10); 2) Exercise (n=10); 3) Middle cerebral artery occlusion (MCAo), n=10); 4) Exercise+MCAo (n=10). Both exercise groups ran on a treadmill at a speed of 15 m/min, 30 min/day for 4 weeks, then, MCAo was performed for 90 min. Brain infarction was measured by Nissl staining. Examination of the remaining neuronal cell after MCAo, and microvascular protein expression on the motor cortex, showed the expression of Neuronal Nuclei (NeuN), Vascular endothelial growth factor (VEGF) & laminin. RESULTS: After 48 hr of MCAo, the infarct volume was significantly reduced in the Ex+MCAo group (15.6+/-2.7%) compared to the MCAo group (44.9+/-3.8%) (p<.05), and many neuronal cells were detected in the Ex+MCAo group (70.8+/-3.9%) compared to the MCAo group (43.4+/-5.1%) (p<.05). The immunoreactivity of laminin, as a marker of microvessels and Vascular endothelial growth factor (VEGF) were intensively increased in the Ex+MCAo group compared to the MCAo group. CONCLUSION: These findings suggest that the neuroprotective effects of exercise pre-conditioning reduce ischemic brain injury through strengthening the microvascular integrity after cerebral ischemia.
Animals ; Brain Infarction/pathology ; Disease Models, Animal ; Infarction, Middle Cerebral Artery/metabolism/pathology/*prevention & control ; Laminin/metabolism ; Male ; Microvessels/metabolism ; Neurons/metabolism ; *Physical Conditioning, Animal ; Rats ; Rats, Sprague-Dawley ; Stroke/prevention & control ; Vascular Endothelial Growth Factor A/metabolism

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PURPOSE: To compare the usefulness of three MR sequences for the depiction and staging of advanced gastriccancer (AGC). MATERIALS AND METHODS: MR imaging was performed in 20 patients in whom AGC was proven by endoscopy.Axial scans with T1-weighted fast low-angle shot (FLASH), T2-weighted turbo spin-echo (TSE), and true fast imagingwith steady state precession (TrueFISP) MR sequences were obtained. We measured the signal-to-noise ratio (S/N) ofgastric cancer and signal difference-to-noise ratio (SD/N) between cancer and intraluminal fluid, cancer and thepancreas, and cancer and perigastric fat in each MR sequence. We also graded lesion conspicuity (poor, fair, orgood), and the degree of serosal invasion in each sequence. All results were correlated with histopathologicfindings. RESULTS: TrueFISP was superior to FLASH or TSE in lesion conspicuity, and showed the highest value ofSD/N between cancer and intraluminal fluid. FLASH showed the highest value of SD/N between cancer and thepancreas, and cancer and perigastric fat. The accuracy of T-staging of AGC with MRI was 75% using FLASH, 70% usingTrueFISP, and 60% using TSE. FLASH sequence understaged in three cases(15%) and overstaged in two (10%). In Usingthe TrueFISP sequence, six cases(30%) were overstaged. CONCLUSION: TrueFISP showed the best lesion conspicuity,but tended to overstage the lesion. T1-weighted FLASH sequence showed the highest value of SD/N on theextraluminal side of the gastric wall, and was better than T2-weighted TSE or TrueFISP for T-staging of AGC.
Humans ; Magnetic Resonance Imaging* ; Signal-To-Noise Ratio ; Stomach Neoplasms*