blood flow measurements
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Healthcare ◽  
2022 ◽  
Vol 10 (1) ◽  
pp. 81
Author(s):  
Asako Shirai ◽  
Tsuyoshi Wadazumi

Ingestion of paprika xanthophyll supplement (PX), which has antioxidant effects, has been recently reported to maintain red blood cell deformability and improve oxygen delivery efficiency. Therefore, we hypothesized that the brain activation induced by multitasking exercise in middle-aged and older participants along with the improved erythrocyte oxygen-carrying efficiency induced by PX supplementation would show a synergistic effect, increasing oxygen supply to the brain and improving cognitive function more effectively. In study 1, cerebral blood flow measurements were conducted during the multitasking exercise and cognitive function tests to verify their effect on cognitive function. The results confirmed that cerebral blood flow increased during the exercise and cognitive function improved after the exercise. In study 2, we compared the effects of the multitasking exercise on cognitive function before and after PX supplementation in middle-aged and older participants to evaluate the effects of PX supplementation. The results suggested that PX supplementation enhanced the effects of active multitasking exercise on cognitive function. We speculate that the improvement of oxygen transport efficiency by PX resulted in more effective oxygen supply, allowing the multitasking exercise to occur more effectively, which was reflected as an improvement in the cognitive function.


2021 ◽  
Author(s):  
Wei Qian ◽  
Qiong Yan ◽  
Xinmiao Jiang ◽  
Jungang Nie ◽  
Jiaqi He ◽  
...  

Abstract To The aim of the current study was to investigate the changes in lncRNA TUG1/miR-320 and related proteins with ischaemic time in an ischemia model. A nude mouse model of lower limb ischemia was established by ligating the femoral artery, and laser Doppler measurements were used to demonstrate the successful establishment of the ischemia model. The cells were extracted from the bone marrow of nude mice, and the proliferation, migration and vascular-forming ability of the cells were analysed. When transplanted into ischemia model mice, blood flow measurements indicated that EPCs can speed up blood flow recovery. The results of HE staining indicated an improvement in inflammatory damage, and immunohistochemistry revealed an increase in capillaries. RT-PCR and Western blot experiments showed that the improvement of ischemia was related to an increase in lncRNA TUG1 and a decrease in miR-320 and that the expression of the related downstream proteins STAT3, VEGFR-2, Wnt-5a and β-catenin increased gradually. These changes promoted an increase in capillaries, the recovery of blood flow, and the improvement of muscle damage. Therefore, EPC transplantation can improve the inflammatory response of lower limb muscles by increasing the expression of lncRNA TUG1 and thereby accelerate the recovery of ischaemic limbs.


2021 ◽  
pp. svn-2021-000858
Author(s):  
Junlin Lu ◽  
Chao Xue ◽  
Xulin Hu ◽  
Yuanli Zhao ◽  
Dong Zhang ◽  
...  

ObjectiveOpen microsurgery, often with bypass techniques, is indispensable for complex aneurysms. To date, it remains unknown whether arterial anatomy or quantitative blood flow measurements can predict insufficient flow-related stroke (IRS). The present study aimed to evaluate the risk factors for IRS in patients treated with open microsurgery with bypass procedures for complex internal carotid artery aneurysms.MethodsPatients with complex aneurysms undergoing bypass surgery were retrospectively reviewed. The recipient/donor flow index (RDFI) was preoperatively evaluated using colour-coding angiography. RDFI was defined as the ratio of the cerebral blood volume of the recipient and donor arteries. The sizes of the recipient and donor arteries were measured. The recipient/donor diameter index (RDDI) was then calculated. IRS was defined as the presence of new postoperative neurological deficits and infarction on postoperative CT scans. We assessed the association between RDFI and other variables and the IRS.ResultsTwenty patients (38±12 years) were analysed. IRS was observed in 12 patients (60%). Patients with postoperative IRS had a higher RDFI than those without postoperative IRS (p<0.001). RDDI was not significantly different between patients with and without IRS (p=0.905). Patients with RDFI >2.3 were more likely to develop IRS (p<0.001).ConclusionQuantitative digital subtraction angiography enables preoperative evaluation of cerebral blood volume. RDFI >2.3, rather than RDDI, was significantly associated with postoperative IRS. This preoperative evaluation allows appropriate decisions regarding the treatment strategy for preventing postoperative IRS.


2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Gabriel Altit ◽  
Shazia Bhombal ◽  
Valerie Y. Chock

Abstract Background Near-infrared spectroscopy (NIRS) measures of cerebral saturation (Csat) and renal saturation (Rsat) in extreme premature newborns may be affected by systemic blood flow fluctuations. Despite increasing clinical use of NIRS to monitor tissue saturation in the premature infant, validation of NIRS measures as a correlate of blood flow is still needed. We compared echocardiography (ECHO) derived markers of ascending aorta (AscAo) and descending aorta (DesAo) blood flow with NIRS measurements obtained during the ECHO. Methods Newborns < 29 weeks’ gestation (2013–2017) underwent routine NIRS monitoring. Csat, Rsat and systemic saturation at the time of ECHO were retrospectively analyzed and compared with Doppler markers of aortic flow. Renal and cerebral fractional tissue oxygen extraction (rFTOE and cFTOE, respectively) were calculated. Mixed effects models evaluated the association between NIRS and Doppler markers. Results Forty-nine neonates with 75 Csat-ECHO and 62 Rsat-ECHO observations were studied. Mean post-menstrual age was 28.3 ± 3.8 weeks during the ECHO. Preductal measures including AscAo velocity time integral (VTI) and AscAo output were correlated with Csat or cFTOE, while postductal measures including DesAo VTI, DesAo peak systolic velocity, and estimated DesAo output were more closely correlated with Rsat or rFTOE. Conclusions NIRS measures are associated with aortic blood flow measurements by ECHO in the extremely premature population. NIRS is a tool to consider when following end organ perfusion in the preterm infant.


2021 ◽  
Vol 8 (2) ◽  
pp. 81-86
Author(s):  
Katarzyna Paczwa ◽  
Justyna Mędrzycka ◽  
Joanna Gołębiewska ◽  
Radosław Różycki

Optical coherence tomography is a non-contact imaging method of the anterior and posterior segments of the eye that is based on laser scanning in spectral domain. This study presents diagnostic possibilities of the new generation Solix FullRange™ OCT&OCTA apparatus (Optovue) to examine meibomian glands, cornea, anterior chamber, as well iridocorneal angles and lens. In the posterior segment of the eye it allows for the precise evaluation of the vitreous body, choroid, retina, optic nerve and blood-flow measurements.


2021 ◽  
pp. 002367722110003
Author(s):  
Kristoffer Kjærgaard ◽  
Michael Sørensen ◽  
Frank Viborg Mortensen ◽  
Aage Kristian Olsen Alstrup

The liver receives dual blood supply from the hepatic artery and portal vein. The pig is often used as an animal model in positron emission tomography (PET) and pharmacokinetic studies because of the possibility for extensive and direct blood sampling. In this study, we compared measurements of hepatic blood flow in 10 female adult Göttingen minipigs and 10 female pre-pubertal Danish Landrace x Yorkshire (DLY) pigs. Ultrasound transit time flow meter probes were placed around the hepatic artery and portal vein through open surgery, hepatic blood flow measurements were performed, and the liver was weighed. Total hepatic blood flow was on average 363 ± 131 mL blood/min in Göttingen minipigs and 988 ± 180 mL blood/min in DLY pigs ( p < 0.001). The mean hepatic blood perfusion was 623 mL blood/min/mL liver tissue and 950 mL blood/min/mL liver tissue ( p = 0.005), and the liver weight was 0.58 kg and 1.04 kg, respectively. The mean arterial flow fraction in Göttingen minipigs was 12 ± 7% and lower than in DLY pigs, where it was 24 ± 7% ( p = 0.001). Using the gold standard for blood flow measurements, we found that both total hepatic blood flow and blood perfusion were significantly lower in Göttingen minipigs than in DLY pigs. The hepatic blood perfusion and arterial flow fraction in DLY pigs were comparable to normative values from humans. Differences in hepatic blood flow between adult Göttingen minipigs and humans should be considered when performing physiological liver studies in this model.


Author(s):  
Adrian Michalopoulos ◽  
Christopher Spelman ◽  
Jitendra Balakumar ◽  
David Slattery

Abstract Avascular necrosis is the most devastating complication of slipped capital femoral epiphysis, leading to collapse of the femoral head, increased risk of osteoarthritis and the requirement of early total hip arthroplasty. It is believed that intraoperative femoral head perfusion assessment may be an accurate predictor of post-operative avascular necrosis (radiographic collapse). At our institution, femoral head perfusion is assessed intraoperatively during all sub-capital realignment procedures. We hypothesize that our method is accurate in predicting the risk of developing post-operative avascular necrosis. In this retrospective study, we collected data from all patients that had intraoperative blood flow measurements during sub-capital realignment procedures. We correlated this with long-term radiographs looking for radiographic collapse. The intraoperative femoral head perfusion assessments during sub-capital realignment procedures for slipped capital femoral epiphysis at our institution, between January 2015 and March 2020 inclusive were assessed for reliability. In total, 26 of 35 patients had intraoperative femoral head perfusion present. Only 2 (8%) of these patients developed radiographic collapse. In contrast, 7 (78%) of the 9 patients who did not have femoral head perfusion present intraoperatively developed radiographic collapse, indicating that our method may be reliable in predicting a patient’s post-operative risk of developing avascular necrosis.


Author(s):  
S. S. Koenders ◽  
J. D. van Dijk ◽  
P. L. Jager ◽  
M. Mouden ◽  
A. G. Tegelaar ◽  
...  

Abstract Background A variety of temporal sampling protocols is used worldwide to measure myocardial blood flow (MBF). Both the length and number of time frames in these protocols may alter MBF and myocardial flow reserve (MFR) measurements. We aimed to assess the effect of different clinically used temporal sampling protocols on MBF and MFR quantification in Rubidium-82 (Rb-82) PET imaging. Methods We retrospectively included 20 patients referred for myocardial perfusion imaging using Rb-82 PET. A literature search was performed to identify appropriate sampling protocols. PET data were reconstructed using 14 selected temporal sampling protocols with time frames of 5-10 seconds in the first-pass phase and 30-120 seconds in the tissue phase. Rest and stress MBF and MFR were calculated for all protocols and compared to the reference protocol with 26 time frames. Results MBF measurements differed (P ≤ 0.003) in six (43%) protocols in comparison to the reference protocol, with mean absolute relative differences up to 16% (range 5%-31%). Statistically significant differences were most frequently found for protocols with tissue phase time frames < 90 seconds. MFR did not differ (P ≥ 0.11) for any of the protocols. Conclusions Various temporal sampling protocols result in different MBF values using Rb-82 PET. MFR measurements were more robust to different temporal sampling protocols.


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