Blood Flow Parameters Research Articles

Safety and efficacy of Symani robotic-assisted microsurgery: Assessment of vascular anastomosis patency, thrombus, and stenosis in a randomized preclinical study

IntroductionThe Symani Surgical System undergoes scrutiny in this study as part of a series of preclinical investigations. Previous studies compared the precision of robotic-assisted anastomoses with manual techniques. This study aims to evaluate critical, histological and gross parameters at site of anastomosis and at distance in a rat model to provide insights into the safety and efficacy of robotic-assisted microsurgery, enhancing its potential for clinical adoption. Materials and MethodsExperienced microsurgeons performed arterial and venous anastomoses in sixteen Wistar rats, randomized in four treatment groups: robotic artery, robotic vein, manual artery, and manual vein. Various parameters were evaluated at two time-points (T0 and T30) on the day of the procedure and at Day 28(T28d). In the second phase of the study animals underwent necropsy, histopathologic analysis and micro-CT scans angiography imaging of anastomosis sites, major organs and distant target organs by a blinded assessor. ResultsPatency rates were 100% at T0 and T30 for all anastomoses, remaining so at T28d for the robotic subgroups, while decreasing to 87.5% for manual arterial anastomoses due to an obstructive thrombus. No evidence of clot migration. Blood flow parameters and procedure times did not significantly differ. The blinded semi-quantitative histological analysis revealed no significant disparities between robotic and manual anastomoses across various pathological indicators. No gross abnormalities were detected in musculoskeletal examinations. ConclusionThis preclinical study demonstrates the safety of the Symani Surgical System. Results suggest equivalence between robotic and manual techniques regarding thrombus formation at the anastomotic site and distal organs.

Relationship between ultrasound parameters of the umbilical and middle cerebral arteries and intrauterine fetal distress

BACKGROUND By comprehensively analyzing the blood flow parameters of the umbilical and middle cerebral arteries, doctors can more accurately identify fetal intrauterine distress, as well as assess its severity, so that timely interventions can be implemented to safeguard the health and safety of the fetus. AIM To identify the relationship between ultrasound parameters of the umbilical and middle cerebral arteries and intrauterine distress. METHODS Clinical data of pregnant women admitted between January 2021 and January 2023 were collected and divided into the observation and control groups (n = 50 each), according to the presence or absence of intrauterine distress. The ultrasound hemodynamic parameters of the uterine artery (UtA), fetal middle cerebral artery (MCA), and umbilical artery (UmA) were compared with neonatal outcomes and occurrence of intrauterine distress in the two groups. RESULTS Comparison of ultrasonic hemodynamic parameters, resistance index (RI), pulsatility index (PI), and systolic maximal blood flow velocity of UmA compared to diastolic blood flow velocity (S/D), revealed higher values of fetal MCA, PI, and S/D of UmA in pregnant women with UtA compared to controls (P < 0.05), while there was no difference between the two groups in terms of RI (P < 0.05) The incidence of a neonatal Apgar score of 8-10 points was lower in the observation group (66.7%) than in the control group (90.0%), and neonatal weight (2675.5 ± 27.6 g) was lower than in the control group (3117.5 ± 31.2 g). Further, cesarean section rate was higher in the observation group (70.0%) than in the control group (11.7%), and preterm labor rate was higher in the observation group (40.0%) than in the control group (10.0%). The incidence of fetal distress, neonatal growth restriction and neonatal asphyxia were also higher in the observation group (all P < 0.05). CONCLUSION Fetal MCA, UmA, and maternal UtA hemodynamic abnormalities all develop in pregnant women with intrauterine distress during late pregnancy, which suggests that clinical attention should be paid to them, and monitoring should be strengthened to provide guidance for clinical intervention.

Evaluation of left ventricular blood flow kinetic energy in patients with acute myocardial infarction by 4D Flow MRI: a preliminary study

PurposeTo evaluate the intracavity left ventricular (LV) blood flow kinetic energy (KE) parameters using four-dimensional (4D) flow cardiovascular magnetic resonance (CMR) in patients with acute myocardial infarction (AMI).MethodsThirty AMI patients and twenty controls were examined via CMR, which included cine imaging, late gadolinium enhancement (LGE) and global heart 4D flow imaging. The KE parameters were indexed to LV end-diastolic volume (EDV) to obtain average, systolic and diastolic KE as well as the proportion of LV in-plane KE (%). These parameters were compared between the AMI patients and controls and between the two subgroups.ResultsAnalysis of the LV blood flow KE parameters at different levels of the LV cavity and in different segments of the same level showed that the basal level had the highest blood flow KE while the apical level had the lowest in the control group. There were no significant differences in diastolic KE, systolic in-plane KE and diastolic in-plane KE between the anterior wall and posterior wall (p > 0.05), only the systolic KE had a significant difference between them (p < 0.05). Compared with those in the control group, the average (10.7 ± 3.3 µJ/mL vs. 14.7 ± 3.6 µJ/mL, p < 0.001), systolic (14.6 ± 5.1 µJ/mL vs. 18.9 ± 3.9 µJ/mL, p = 0.003) and diastolic KE (7.9 ± 2.5 µJ/mL vs. 10.6 ± 3.8 µJ/mL, p = 0.018) were significantly lower in the AMI group. The average KE in the infarct segment was lower than that in the noninfarct segment in the AMI group (49.5 ± 18.7 µJ/mL vs. 126.3 ± 50.7 µJ/mL, p < 0.001), while the proportion of systolic in-plane KE increased significantly (61.8%±11.5 vs. 42.9%±14.4, p = 0.001).ConclusionThe 4D Flow MRI technique can be used to quantitatively evaluate LV regional hemodynamic parameters. There were differences in the KE parameters of LV blood flow at different levels and in different segments of the same level in healthy people. In AMI patients, the average KE of the infarct segment decreased, while the proportion of systolic in-plane KE significantly increased.

Timing of capillary enlargement after adenoviral VEGF gene transfer does not support post-ischemic skeletal muscle recovery in hyperlipidemic mice

Abstract Funding Acknowledgements Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Finish Academy (Clinical Researcher 324070 and Research Project 339560). Finnish Foundation for Cardiovascular Research Background Transient capillary enlargement has been shown to be essential for successful post-ischemic tissue recovery as it may facilitate the return of arterial driving pressure by supporting collateral maturation. It also leads to an intussusceptive increase in capillary density that supports efficient oxygen delivery and muscle regeneration. Hyperlipidemia has been shown to blunt post-ischemic capillary reactivity and hinder skeletal muscle recovery from ischemia. Therefore, it can be hypothesized that correction of capillary reactivity might improve post-ischemic muscle recovery under hyperlipidemia. Purpose The aim of this study was to test the ability of angiogenic VEGF gene therapy in improving post-ischemic muscle recovery under hyperlipidemia. Methods AdVEGF gene transfer was performed into the calf muscles of aged, hyperlipidemic LDLR-/-ApoB100/100 mice after acute ischemia induction. The effects of AdVEGF on capillary phenotype, tissue edema, restoration of blood flow parameters, microvascular hemoglobin oxygenation and tissue damage/regeneration were evaluated for up to 29 days post-procedure as compared to AdLacZ control using immuno- and histological analyses, magnetic resonance, contrast-enhanced ultrasound and photoacoustic imaging, respectively. Results AdVEGF gene therapy was able to promote capillary enlargement that led to recovery of arterial driving pressure in ischemic LDLR-/-ApoB100/100 muscles. However, capillary enlargement induced by AdVEGF appeared late, lasted up to 29 days and did not promote intussusception. Consequently, the negative effect of long-lasting enlargement, i.e., massive tissue edema, delayed blood flow recovery and aggravated ischemic tissue damage. Conclusion Proper time of induction and duration of capillary enlargement are crucial to yield a functional vascular response supporting post-ischemic tissue recovery.

The impact of diffusion and perfusion-weighted imaging on glioma grading

Abstract Objectives Determining the grade of a glioma is extremely important for treatment planning and prognosis prediction. The study aimed to evaluate the usefulness of multiparametric perfusion-weighted imaging (PWI) and diffusion-weighted imaging (DWI) in preoperative glioma grading. Methods In this retrospective study, 63 individuals with brain tumors histologically confirmed, of which 23 had low-grade gliomas (LGGs) and 40 had high-grade gliomas (HGGs) were involved. We conducted this paper on apparent diffusion coefficient (ADC) maps using the entire tumor volume method, allowing us to use all ADC values of the tumor. Small-sample regions of interest (ROIs) were drawn to collect parameters of relative cerebral blood flow (rCBF), cerebral blood flow (CBF), and relative cerebral blood volume (rCBV), from both the tumor core and peritumoral edema. The PWI and DWI metrics were compared to identify the most accurate distinguishing HGGs and LGGs, analyze receiver operating characteristics (ROC), and evaluate the diagnostic performance using solitary parameters and combined. Results In diffusion MRI, there were significant differences in minimum ADC and mean ADC between LGGs and HGGs (p&lt;0.05), with the larger area under the curve (AUC) of 0.898 found for mean ADC at a cut-off value of 1.275, with sensitivity of 82.6 % and specificity of 90 %. The maximum ADC value did not differ significantly (p&gt;0.05). All perfusion parameters in both the tumor core and peritumoral edema area were significantly greater values in cases of HGG compared to LGG (p&lt;0.001), with the highest AUC of 0.946 found for solid tumor rCBV value (rCBVt), the cut-off is 3.585, sensitivity of 85 % and specificity of 100 %. Combining mean ADC and rCBVt provided an excellent AUC of 0.975, a sensitivity of 92.5 %, and a specificity of 91.3 % for differentiating between HGGs and LGGs. Conclusions Perfusion and diffusion MRI are valuable in discriminating between high-grade and low-grade gliomas, with the major criterion in the decision-making process being the combined mean ADC and rCBVt parameters.

Effect of Intrauterine Perfusion of Granulocyte Colony-Stimulating Factor on Endometrium and Blood Flow Parameters in Patients With Thin Endometrium: A Prospective Controlled Clinical Trial

To investigate the effects of intrauterine perfusion with granulocyte colony-stimulating factor (G-CSF) on the endometrial thickness, volume, and blood flow parameters of patients with thin endometrium and their clinical outcomes. We designed a prospective non-randomized synchronous controlled trial and recruited patients with thin endometrium who underwent frozen-thawed embryo transfer (FET) at Mianyang Central Hospital between September 1, 2021 and September 1, 2023. They were divided into two groups, an experimental group of patients who received the experimental treatment of intrauterine perfusion with G-CSF and a control group of patients who did not receive the experimental treatment. The general data and the clinical outcomes of the two groups were analyzed and compared. The endometrial thickness, volume and blood flow parameters of patients in the experimental group before and after intrauterine perfusion with G-CSF were analyzed. The clinical data of 83 patients were included in the study. The experimental group included 51 cases, while the control group included 31 cases. There were no significant differences in the baseline data between the two groups. The clinical pregnancy rate of the experimental group (56.86%) was higher than that of the control group (50.00%) and the rate of spontaneous abortion in the experimental group (27.59%) was lower than that in the control group (37.50%), but the differences were not statistically significant (P>0.05). In the experimental group, the postperfusion endometrial thickness ([0.67±0.1] cm) was greater than the preperfusion endometrial thickness ([0.59±0.09] cm), the postperfusion ([1.84±0.81] cm3) was greater than the preperfusion endometrial volume ([1.54±0.69] cm3), and the postperfusion vascularization flow index (VFI) (1.97±2.82) was greater than the preperfusion VFI (0.99±1.04), with all the differences being statistically significant (P<0.05). Intrauterine perfusion with G-CSF can enhance the endometrial thickness, volume, and some blood flow parameters in patients with thin endometrium.

Laser speckle flowgraphy has comparable accuracy to indocyanine green fluorescence angiography in assessing bowel blood perfusion.

To investigate the accuracy of laser speckle flowgraphy (LSFG), a noninvasive method for the quantitative evaluation of blood flow using mean blur rate (MBR) as a blood flow parameter in the assessment of bowel blood perfusion compared to indocyanine green fluorescence angiography (ICG-FA). We enrolled 46 patients who underwent left-sided colorectal surgery. LSFG and ICG-FA were applied to assess blood bowel perfusion, with MBR and luminance as parameters, respectively. In both measurement methods, the position where the parameter suddenly decreased was defined as the blood flow boundary line. Subsequently, the blood flow boundaries created after processing the blood vessels flowing into the intestinal tract were determined using LSFG and ICG-FA, and concordance between the two was examined. Blood flow boundaries were visually identified using color tone changes on a color map created based on MBR in LSFG and using differences in luminance in ICG-FA. The distances between the transection line and blood flow boundaries determined using each method were compared. The location of blood flow boundaries matched in 65% (30/46) of cases. Although locations differed in the remaining 35% (16/46), all were located on the anal side near the transection line, and the difference was not clinically significant. The average distances between the transection line and blood flow boundary were 2.76 (SD = 3.25) and 3.71 (SD = 4.26) mm, respectively. There was no statistically significant difference between the two groups (p = 0.38). LSFG was shown to have comparable accuracy to ICG-FA, and may be useful for evaluating bowel perfusion.

Doppler ultrasound surveillance of recently formed haemodialysis arteriovenous fistula: the SONAR observational cohort study.

Arteriovenous fistulas are considered the best option for haemodialysis provision, but as many as 30% fail to mature or suffer early failure. To assess the feasibility of performing a randomised controlled trial that examines whether, by informing early and effective salvage intervention of fistulas that would otherwise fail, Doppler ultrasound surveillance of developing arteriovenous fistulas improves longer-term arteriovenous fistula patency. A prospective multicentre observational cohort study (the 'SONAR' study). Seventeen haemodialysis centres in the UK. Consenting adults with end-stage renal disease who were scheduled to have an arteriovenous fistula created. Participants underwent Doppler ultrasound surveillance of their arteriovenous fistulas at 2, 4, 6 and 10 weeks after creation, with clinical teams blinded to the ultrasound surveillance findings. Fistula maturation at week 10 defined according to ultrasound surveillance parameters of representative venous diameter and blood flow (wrist arteriovenous fistulas: ≥ 4 mm and > 400 ml/minute; elbow arteriovenous fistulas: ≥ 5 mm and > 500 ml/minute). Mixed multivariable logistic regression modelling of the early ultrasound scan data was used to predict arteriovenous fistula non-maturation by 10 weeks and fistula failure at 6 months. A total of 333 arteriovenous fistulas were created during the study window (47.7% wrist, 52.3% elbow). By 2 weeks, 37 (11.1%) arteriovenous fistulas had failed (thrombosed), but by 10 weeks, 219 of 333 (65.8%) of created arteriovenous fistulas had reached maturity (60.4% wrist, 67.2% elbow). Persistently lower flow rates and venous diameters were observed in those fistulas that did not mature. Models for arteriovenous fistulas' non-maturation could be optimally constructed using the week 4 scan data, with fistula venous diameter and flow rate the most significant variables in explaining wrist fistula maturity failure (positive predictive value 60.6%, 95% confidence interval 43.9% to 77.3%), whereas resistance index and flow rate were most significant for elbow arteriovenous fistulas (positive predictive value 66.7%, 95% confidence interval 48.9% to 84.4%). In contrast to non-maturation, both models predicted fistula maturation much more reliably [negative predictive values of 95.4% (95% confidence interval 91.0% to 99.8%) and 95.6% (95% confidence interval 91.8% to 99.4%) for wrist and elbow, respectively]. Additional follow-up and modelling on a subset (n = 192) of the original SONAR cohort (the SONAR-12M study) revealed the rates of primary, assisted primary and secondary patency arteriovenous fistulas at 6 months were 76.5, 80.7 and 83.3, respectively. Fistula vein size, flow rate and resistance index could identify primary patency failure at 6 months, with similar predictive power as for 10-week arteriovenous fistula maturity failure, but with wide confidence intervals for wrist (positive predictive value 72.7%, 95% confidence interval 46.4% to 99.0%) and elbow (positive predictive value 57.1%, 95% confidence interval 20.5% to 93.8%). These models, moreover, performed poorly at identifying assisted primary and secondary patency failure, likely because a subset of those arteriovenous fistulas identified on ultrasound surveillance as at risk underwent subsequent successful salvage intervention without recourse to early ultrasound data. Although early ultrasound can predict fistula maturation and longer-term patency very effectively, it was only moderately good at identifying those fistulas likely to remain immature or to fail within 6 months. Allied to the better- than-expected fistula patency rates achieved (that are further improved by successful salvage), we estimate that a randomised controlled trial comparing early ultrasound-guided intervention against standard care would require at least 1300 fistulas and would achieve only minimal patient benefit. This trial is registered as ISRCTN36033877 and ISRCTN17399438. This award was funded by the National Institute for Health and Care Research (NIHR) Health Technology Assessment programme (NIHR award ref: NIHR135572) and is published in full in Health Technology Assessment; Vol. 28, No. 24. See the NIHR Funding and Awards website for further award information.

CORRELATION BETWEEN RETINAL MICROCIRCULATION, ECHOCARDIOGRAPHIC PARAMETERS AND MYOCARDIAL CORONARY FLOW RESERVE

Objective: Arterial hypertension causes cardiac functional and structural alterations. In hypertensive patients without flow-limiting epicardial coronary artery disease, we investigated the possible relationship between retinal microcirculation, positron emission tomography myocardial blood flow (MBF) and echocardiographic parameters of left ventricular (LV) performance, including mechano-energetic efficiency indexed for myocardial mass (MEEi) Design and method: Nineteen hypertensive patients (mean age 65 ± 11, 10 F) without flow-limiting epicardial coronary artery disease underwent patients wall-to-lumen ratio (WLR) and the cross-sectional area of the vascular wall (WCSA) of retinal arterioles by an Adaptive Optics (AO) retinal camera, echocardiography, including MEEi computation, and cardiac 13NH3 positron emission tomography (13NH3 PET) with assessment of myocardial coronary flow reserve (CFR). A positive 13NH3 PET was defined as a ratio of stress (regadenoson) myocardial blood flow (MBF)/mass and resting MBF/mass lower than 2. Results: No significant differences of demographic parameters were observed between patients with positive (n=6) vs negative (n=13) 13NH3 PET. In all patients WLR was significantly related to BMI (0,50, p=0.02), age (r=0.49, p=0.03)and LVMi (r=0.48, p=0.03) at univariate analysis. A negative correlation was also observed between WLR and total CFR (-0.64, p=0.003) and MMEi (-0.35, p=0.13). The relationship between WLR and CFR remained significant after adjustment for age and BMI (r=-0.49, p=0.047). Conclusions: In hypertensive patients without flow-limiting epicardial coronary artery disease, retinal WLR could reflect the presence of structural alterations in coronary microcirculation, possibly contributing to an impairment of CFR and to early LV dysfunction, as detected by low values of MEEi.

DOES EXERCISE CHANGE BLOOD FLOW TO TUMOURS? ACUTE AEROBIC EXERCISE EFFECTS ON LIVER METASTASES BLOOD FLOW: A CASE SERIES

AIM Effective cancer treatment relies on intravenous chemotherapy penetrating the entire tumour in sufficient concentrations, which is largely reliant on effective blood supply into and within the tumour. However, tumours contain abnormal vasculature with inefficient blood perfusion leading to the inability for chemotherapy to reach the target tumour. Pre-clinical evidence suggests acute exercise may increase blood flow by 200%. However, most pre-clinical studies investigate the effects of light-to-moderate intensity exercise and subsequently there is little evidence regarding the most effective exercise intensity for improved tumour vasculature. Therefore, the aim of this ongoing case series is to determine whether exercise changes tumour blood flow in a clinical model using non-invasive techniques, and how exercise intensity effects degree of change in blood flow to tumours in patients with liver metastases. METHODS Participants were eligible if they were aged over 18 years, had stage IV cancer with liver metastasis and ECOG 0-2. The study visit consisted of an aerobic fitness test (YMCA) to determine cardiorespiratory fitness and three 5-minute bouts of exercise at low, moderate and high intensities. After each exercise bout, Doppler ultrasound was used to measure a liver tumour vessel and the hepatic artery (as a control) to determine blood flow parameters. RESULTS Exercise increased peak systolic velocities (PSV) to liver tumours at all intensities compared to rest. Moderate and high exercise intensities showed a marked increase in PSV within the first 2 minutes after exercise. The hepatic artery showed less variability in PSV with time compared to the liver tumour. Cardiorespiratory fitness did not affect tumour PSV. CONCLUSION The results of this case series thus far suggest that exercise increases tumour blood flow at all exercise intensities with particular emphasis on moderate and high intensities. This supports the potential for using exercise as an adjunct to standard treatment to improve chemotherapy efficacy.

Kidney computed tomography perfusion in patients with ureteral obstruction.

Kidney perfusion on CT is an encouraging surrogate for renal scintigraphy in assessing renal function. However, data on dynamic volumetric CT in patients with kidney obstruction is lacking. Thus, the aim of this study is to determine the feasibility of CT-based renal perfusion using a dynamic volume to assess renal hemodynamics at different degrees and durations of obstruction. We included patients with unilateral kidney obstruction in our single-center, prospective study. The patients were divided into three groups. Patients without dilatation of the pelvicalyceal system (PCS) and normal parenchyma thickness were included into Group 1; patients with PCS dilatation and parenchyma thickness 1.8-2.4 cm-into Group 2; and patients with ureteropyelocalicoectasia and parenchyma thickness less than 1.8 cm-into Group 3. Total of 56 patients were enrolled. In Group 1 mean values of cortical and medullar arterial blood flow, blood volume, and extraction fraction were within the normal range. Changes in contralateral kidney were not determined. Patients from Group 2 showed significant differences in blood flow parameters in the cortical and medulla of the obstructed kidney. No changes in perfusion values in the contralateral kidney was observed. In patients from Group 3 there was a marked decrease in perfusion on the side of obstruction compared to Group 2, indicating that the degree of expansion of the PCS directly correlates with the change in blood flow. However, in the contralateral kidney, these indicators exceeded the normal values of perfusion. CT perfusion allows to objectively assess changes in blood flow in the setting of renal obstruction. The degree of obstruction directly affects the measured rate of blood flow.

Prognostic value of resistive index (measured in anterior cerebral artery) in term neonates with hypoxic ischemic encephalopathy

Background: Perinatal asphyxia refers to a condition during the first and second stage of labor and soon after birth in which impaired gas exchange leads to acidosis, hypoxemia, and hypercarbia. The Doppler technique is a non-invasive method that can be used at the bed side without disturbing patients, for risk of subsequent neurodevelopment impairment in HIE. It has been proven that impaired cerebral circulation plays the main role in the pathogenesis of hypoxic ischemic brain injury in neonates. Methods: Doppler sonography conducted in all enrolled subjects. Cerebral blood flow parameters-peak systolic velocity, end diastolic velocity and resistive index were measured in anterior cerebral artery bilaterally on parasagittal planes obtaining the images through the anterior fontanelle with in first 72 hours. Results: In our study we found that death during hospital stay in neonates with normal RI and abnormal RI is 13% and 28.6% respectively (p&lt;0.01). Abnormal neurological outcome of 70.6% at 6 months and 64.7% at 12 months in patients with abnormal RI and 23.3% at 6 months and 18.6% at 12 months in patients with normal RI (p&lt;0.01). Conclusions: There is a significant correlation between neurodevelopmental disabilities and cerebral blood flow parameters in neonates with hypoxic ischemic encephalopathy. Detection of increased or decreased in cerebral blood flow velocities in neonates with in first 72 hours postpartum has a significant prognostic value related to death and long-term neurodevelopmental outcome.

Ultrasonographic diagnosis of fetal hemodynamic parameters in pregnant women with diabetes mellitus in the third trimester of pregnancy

ObjectiveIt was to investigate the diagnosis of fetal hemodynamics in pregnant women with diabetes mellitus in the third trimester of pregnancy by color Doppler ultrasonography. Methods55 women with gestational diabetes mellitus (GDM) in the third trimester of pregnancy who were clinically diagnosed and treated in Haian City People's Hospital of Jiangsu Province were selected as the observation group, and 55 pregnant women with normal prenatal examination results were selected as the controls. The hemodynamic parameters of fetal middle cerebral artery (MCA), umbilical artery (UA), and renal artery (RA) were detected, including the ratio of maximum systolic blood flow velocity to end-diastolic blood flow velocity (S/D), resistance index (RI) and arterial pulsation index (PI). Fasting serum levels of maternal patients were collected for detecting Cystain C (Cys C) and homocysteine (Hcy) to analyze the predictive value of serological indexes and target arterial hemodynamics parameters for adverse pregnancy outcome (APO). ResultsThe results showed that compared with controls, in the observation group, RI, PI, and S/D of MCA and RA increased significantly, while RI, PI and S/D of UA decreased obviously (P < 0.05), the levels of serum Cys C and Hcy were clearly increased (P < 0.05). The APO rate of controls and observation group was 10.91 % and 25.45 %, respectively. It was found that the area under the curve of serum Cys C, Hcy, and the APO predicted by the hemodynamic parameters of fetal MCA, UA, and RA were all greater than 0.75 (P < 0.05). Multiple Logistic regression analysis showed that serum Cys C and Hcy, and the hemodynamic parameters of fetal MCA, UA and RA were correlated with APO (P < 0.05). ConclusionIn summary, maternal blood glucose level can affect fetal hemodynamic parameters. In the third trimester of pregnancy, the changes of blood flow parameters of fetal MCA, UA, RA, and maternal serum Cys C and Hcy levels are helpful to understand fetal status in utero, and can be used to predict APO.

Effects of acupuncture for Bell's palsy patients in the acute phase and its impact on facial nerve edema: a study protocol for a randomized, controlled trial.

Bell's palsy is an acute peripheral facial neuropathy, which is one of the most common causes of facial palsy of lower motor neurons. Facial nerve swelling is commonly observed in Bell's palsy. Acupuncture therapy has been widely used in the treatment of Bell's palsy. However, whether acupuncture can be effectively used in the acute stage is still controversial. There are no clinical trials conducted previously to evaluate the effect of acupuncture on facial nerve edema in Bell's palsy patients. The study aims to evaluate the potential efficacy of different acupuncture modalities on Bell's palsy patients in the acute phase, its effect on facial nerve edema, and to preliminarily explore its possible mechanism. In this randomized, controlled trial, 165 Bell's palsy patients with unilateral onset within 3 days will be recruited and randomly assigned to either the electroacupuncture group (n = 33), the acupuncture group (n = 33), the sham acupuncture group (n = 33), the blank control group (n = 33), or the acupuncture control group (n = 33) in a 1:1:1:1:1 ratio. The participants will receive 4 weeks of treatment and 8 weeks of follow-up. The five groups of participants will receive the following treatments: A: Electroacupuncture + Medication (prednisone acetate tablets, mecobalamin tablets, and vitamin B1 tablets); B: Acupuncture + Medication; C: Sham Acupuncture + Medication; D: Medication only; and E: Acupuncture only. The primary outcome will be the effectiveness rate of different acupuncture modalities in improving facial nerve function after the intervention period. The secondary outcomes will be the recovery speed, the diameter of the facial nerve, the echo intensity and thickness of facial muscles, blood flow parameters of the facial artery, the serum inflammatory level, safety evaluation, and adverse events. Preliminary exploration of its mechanism of action occurs through inflammation and immune response. The difference between groups will be assessed using repeated measure analysis of covariance (ANCOVA) and trend chi-square. The trial will evaluate the efficacy and facial nerve edema of acupuncture for Bell's palsy patients in the acute phase and preliminarily explore its possible mechanism. The results thus may provide evidence for clinical application. https://www.chictr.org.cn/bin/project/edit?pid=133211, identifier ChiCTR2100050815.

Fetal Aortic Blood Flow Velocity and Power Doppler Profiles in the First Trimester: A Comprehensive Study Using High-Definition Flow Imaging.

This study aimed to establish reference values for fetal aortic isthmus blood flow velocity and associated indices during the first trimester, utilizing a novel ultrasonographic technique known as high-definition flow imaging (HDFI). Additionally, the correlation between Doppler profiles of aortic blood flow and key fetal parameters, including nuchal thickness (NT), crown-rump length (CRL), and fetal heartbeat (FHB), was investigated. A total of 262 fetuses were included in the analysis between December 2022 and December 2023. Utilizing 2D power Doppler ultrasound images, aortic blood flow parameters were assessed, including aortic peak systolic velocity (PS), aortic end-diastolic velocity (ED), aortic time average maximal velocity (TAMV), and various indices such as aortic systolic velocity/diastolic velocity (S/D), aortic pulsatile index (PI), aortic resistance index (RI), aortic isthmus flow velocity index (IFI), and aortic isthmic systolic index (ISI). Concurrently, fetal FHB, NT, and CRL were evaluated during early trimester Down syndrome screening. Significant findings include a positive correlation between gestational age (GA) and PS (PS = 3.75 × (GA) - 15.4, r2 = 0.13, p < 0.01), ED (ED = 0.42 × (GA) - 0.61, r2 = 0.04, p < 0.01), PI (PI = 0.07 × (GA) + 1.03, r2 = 0.04, p < 0.01), and TAMV (TAMV = 1.23 × (GA) - 1.66, r2 = 0.08, p < 0.01). In contrast, aortic ISI demonstrated a significant decrease (ISI = -0.03 × (GA) + 0.57, r2 = 0.05, p < 0.05) with gestational age. No significant correlation was observed for aortic RI (p = 0.33), S/D (p = 0.39), and IFI (p = 0.29) with gestational age. Aortic PS exhibited positive correlations with NT (0.217, p = 0.001) and CRL (0.360, p = 0.000) but a negative correlation with FHB (-0.214, p = 0.001). Aortic PI demonstrated positive correlations with CRL (0.208, p = 0.001) and negative correlations with FHB (-0.176, p = 0.005). Aortic TAMV showed positive correlations with NT (0.233, p = 0.000) and CRL (0.290, p = 0.000) while exhibiting a negative correlation with FHB (-0.141, p = 0.026). Aortic ISI demonstrated negative correlations with NT (-0.128, p = 0.045) and CRL (-0.218, p = 0.001) but a positive correlation with FHB (0.163, p = 0.010). Power Doppler angiography with Doppler ultrasound demonstrates the ability to establish accurate reference values for fetal aortic blood flow during the first trimester of pregnancy. Notably, aortic PS, TAMV, and ISI exhibit significant correlations with NT, CRL, and FHB, with ISI appearing more relevant than IFI, PS, TAMV, and FHB. The utilization of HDFI technology proves advantageous in efficiently detecting the site of the aortic isthmus compared to traditional color Doppler mode in early second trimesters.

Echocardiographic parameters as adjuncts to the Pulmonary Embolism Severity Index in predicting 30-day mortality in acute pulmonary embolism patients.

The Pulmonary Embolism Severity Index (PESI) is a validated tool to predict 30-day all-cause mortality in patients with acute pulmonary embolism (PE) but includes only clinical variables. We aimed to determine the effectiveness of PESI extended with an echocardiographic parameter. This cross-sectional observational study included consecutive patients with acute PE diagnosed with computed tomography pulmonary angiography. Of 117 subjects (57 men, 48.7%), at a median age of 69 (59-80) years, 16 patients died during the 30-day follow-up. Six modified models of PESI with an additional single echocardiographic parameter were created, which increased the predictive value of PESI (area under the curve [AUC] 0.8608): tricuspid annular plane systolic excursion (TAPSE) <18 mm, right ventricular (RV) free wall longitudinal strain (RVFWLS) >-23%, 60/60 sign, RV global longitudinal strain (RVGLS) >-16%, pulmonary ejection acceleration time (AcT) <67 ms, and thrombus in right heart cavities (AUC 0.8657 to 0.8976, respectively, all markers P <0.001). TAPSE, AcT, RVFWLS, and RVGLS showed significant correlations with the PESI score, but not a thrombus in the right heart cavity or the 60/60 sign. As PESI adjuncts, they independently predicted fatal outcomes: thrombus with hazard ratio (HR) 10.04 (95% confidence interval [CI], 2.81-37.12; P <0.001) and the 60/60 sign with HR 4.07 (95% CI, 1.27-12.81; P <0.001). The quantitative echocardiographic parameters of RV systolic function and pulmonary artery blood flow are associated with the PESI score and thus increase its predictive value to a limited extent. PE- specific findings: a thrombus in the right heart cavity and the 60/60 sign are effective adjuncts to the PESI score.

Correlation of retrobulbar perfusion deficits with glaucomatous visual field defects.

This study is to evaluate the correlation between retrobulbar perfusion deficits and glaucomatous visual field defects. Eighty-four patients with glaucoma and 17 normal subjects serving as controls were selected. Color Doppler imaging (CDI) was used to measure the changes in blood flow parameters in the retrobulbar ophthalmic artery (OA), central retinal artery (CRA), and short posterior ciliary arteries (SPCAs). Visual field testing was performed using a Humphrey perimeter, categorizing the visual field deficits into four stages according to the Advanced Glaucoma Intervention Study (AGIS) scoring method. Subsequently, the correlation of retrobulbar hemodynamic parameter alterations among glaucomatous patients with varying visual field defects was examined. The higher the visual field stage, the lower the peak systolic velocity (PSV) of the OA, CRA, and SPCAs in glaucomatous patients. The CRA had the highest sensitivity to changes in its PSV. The PSV of the temporal SPCA (TSPCA-PSV) was lower in advanced glaucoma than in early-stage glaucoma. The PSVs of the OA, CRA, and TSPCA, as well as the resistance index of the CRA (CRA-RI), were positively correlated with the visual field index and the mean deviation. Except for that of OA, the PSV of the retrobulbar vessels was negatively correlated with the pattern standard deviation (PSD). The OA-PSV and end-diastolic velocity (EDV) of the CRA and TSPCA were lower in patients with superior visual field defects than in those with inferior visual field defects. Greater severity of visual field defects corresponded to poorer retrobulbar blood flow in glaucomatous patients. Patients suffered significant perfusion impairments in the CRA at the early stage, accompanied by SPCA perfusion disorder at the advanced stage. The presence of a bow-shaped defect in the superior or inferior region of the visual field in moderate-stage glaucoma was closely correlated with retrobulbar vascular EDV. ChiCTR2200059048 (2022-04-23).

Biomimetic approach to the design of artificial small‑diameter blood vessels

Objective: To create 2-mm diameter multilayer porous tubular scaffolds (PTS) with characteristics that resemble small-diameter native blood vessels in terms of characteristics.Materials and methods. PTS made of polycaprolactone (PCL, MM 80000) with a PCL-made sealing coat/layer with gelatin addition (PCL-gelatin) with a diameter of 2 mm were created by electrospinning (NANON-01A). Bioactive coating was applied to the PTS surface by sequential incubation in solutions of bovine serum albumin, heparin (Hp), and platelet lysate (PL). Cytotoxicity was investigated under conditions of direct contact of PTS with a monolayer of NIH/3T3 mouse fibroblasts. Viability of human umbilical vein endothelial cells (EA.hy926) was evaluated using Live/Dead® Viability/Cytotoxicity Kit. Permeability and blood flow parameters of the PTS implanted in the infrarenal section of the rat aorta were recorded using Doppler imaging.Results. A three-layer PTS construct with an inner diameter of 2 mm was developed. Its inner and outer layers were formed from 0.2 mL of PCL solution, and the middle sealing coat/layer was from 0.5 mL of PCL with addition of 30% (by weight of polymer) gelatin. Introduction of the sealing coat/layer reduced surgical porosity (SP) from 56.2 ± 8.7 mL/(cm2·min) for a single-layer PTS made of pure PCL to 8.9 ± 2.6 mL/(cm2·min) for a three-layer PTS. The resulting PTS demonstrated physicomechanical characteristics similar to those of native blood vessels; it also showed no cytotoxicity. Application of a bioactive coating of Hp and PL allowed for increased in vitro adhesion and proliferation of endothelial cells. The technique of implantation of 10 mm long fragments of three-layer PTS into the infrarenal section of a rat aorta was corrected, thus minimizing blood loss and narrowing the anastomosis site. In an acute experiment, it was proven that the prostheses were patent and that blood flow parameters (systolic and diastolic velocity, resistivity index) were close to the corresponding indicators of native rat aorta.Conclusion. The developed three-layer PTS constructs have low SP and physicomechanical properties close to those of native blood vessels. Bioactive coating improves the in vitro matrix properties of PTS relative to human endothelial cells. At short-term implantation into the aorta of experimental animals, PTS showed no early thrombosis, while blood flow parameters were close to those of native rat aorta. Thus, three-layer PTS with bioactive coating can be used as a scaffold for creation of in situ tissue-engineered construct of a small-diameter blood vessel.

Associations between 3D-based Left Atrial Volumetric and Blood Flow Parameters in a Single-Site Cohort of the Multi-Ethnic Study of Atherosclerosis.

Purpose To investigate associations between left atrial volume (LAV) and function with impaired three-dimensional hemodynamics from four-dimensional flow MRI. Materials and Methods A subcohort of participants from the Multi-Ethnic Study of Atherosclerosis from Northwestern University underwent prospective 1.5-T cardiac MRI including whole-heart four-dimensional flow and short-axis cine imaging between 2019 and 2020. Four-dimensional flow MRI analysis included manual three-dimensional segmentations of the LA and LA appendage (LAA), which were used to quantify LA and LAA peak velocity and blood stasis (% voxels < 0.1 m/sec). Short-axis cine data were used to delineate LA contours on all cardiac time points, and the resulting three-dimensional-based LAVs were extracted for calculation of LA emptying fractions (LAEFtotal, LAEFactive, LAEFpassive). Stepwise multivariable linear models were calculated for each flow parameter (LA stasis, LA peak velocity, LAA stasis, LAA peak velocity) to determine associations with LAV and LAEF. Results This study included 158 participants (mean age, 73 years ± 7 [SD]; 83 [52.5%] female and 75 [47.4%] male participants). In multivariable models, a 1-unit increase of LAEFtotal was associated with decreased LA stasis (β coefficient, -0.47%; P < .001), while increased LAEFactive was associated with increased LA peak velocity (β coefficient, 0.21 cm/sec; P < .001). Furthermore, increased minimum LAV indexed was most associated with impaired LAA flow (higher LAA stasis [β coefficient, 0.65%; P < .001] and lower LAA peak velocity [β coefficient, -0.35 cm/sec; P < .001]). Conclusion Higher minimum LAV and reduced LA function were associated with impaired flow characteristics in the LA and LAA. LAV assessment might therefore be a surrogate measure for LA and LAA flow abnormalities. Keywords: Atherosclerosis, Left Atrial Volume, Left Atrial Blood Flow, 4D Flow MRI Supplemental material is available for this article. © RSNA, 2024.

Diagnostic paradoxes of sepsis

Sepsis is currently one of the most important problems of medicine, and the treatment of this category of patients presents great difficulties and is characterized by high mortality. Acute Pneumonia (AP) has been the leading cause of septic conditions for many years, the proportion of which has recently begun to exceed half of all cases. The modern concept of AP considers the causative agent of the disease as the main cause of its occurrence and development, but for many years the search for reliable differential diagnostic criteria depending on the etiology has not been found. The peculiarities of the localization of AP, unlike other inflammatory diseases, force us to pay attention to the fundamental differences in the parameters of blood flow in the two circulatory circles. The inevitability of the onset of the inflammatory process with a vascular reaction forces us to understand the mechanisms of AP development on the basis of already studied, confirmed, and classical materials of medical science. New ideas about the pathogenesis of the disease make it possible to understand its leading importance in the observed pattern of AP and to recognize the obvious over diagnosis of sepsis in this category of patients. Understanding the need for such a step can significantly reduce the number of patients with sepsis, and a pathogenetic approach to medical care will really improve treatment outcomes.