Correlation Between Fetal Weight Gain and Birth Weight with Blood Flow in the Uterine Arteries Calculated with the PixelFlux Technique

Abstract Introduction The aim was to investigate correlations between fetal weight gain/day and birthweight with blood flow estimates in the uterine arteries calculated with the PixelFlux technique and with measurements from TAmax. We also aimed to examine the agreement between estimates using the two methods. Material and methods We conducted a prospective observational pilot study in pregnancy week 24–25 in women with risk pregnancies referred to the fetal medical centre at St. Olavs Hospital, Trondheim, Norway from March 2016 to June 2016. Blood flow in the uterine arteries was calculated using time-averaged peak velocity (TAmax) and the PixelFlux technique. PixelFlux is a method based on pixelwise calculation of spatially angle-corrected velocities and areas of all pixels inside a vessel during a heart cycle. Results The mean flow calculated from PixelFlux and TAmax was 811 ml/minute and 787 ml/minute, respectively. The intra-class correlation coefficient was 0.83 (95% CI 0.72-0.90) and limits of agreement were −441 ml/minute (95% CI -558 to −324 ml/minute) to 489 ml/minute (95% CI 372 to 606 ml/minute). We observed a significant correlation between mean flow calculated from PixelFlux and birthweight (r=0.41; p<0.01) and between flow calculated from PixelFlux and weight gain/day (r=0.33; p=0.02). Calculation based on TAmax was significant correlated to birthweight (r=0.34; p=0.02), but not to weight-gain/day. Pulsatile index was not correlated to flow, birthweight or fetal weight-gain/day. Conclusions We found significant correlations between estimated blood flow in the uterine arteries using the PixelFlux technique with fetal weight-gain/day and with birthweight. Estimates from two methods showed good agreement.

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Abstract P531: Cerebral Blood Flow Analysis Using Flow Wire Measurements and CFD Analysis

Stroke ◽

10.1161/str.52.suppl_1.p531 ◽

2021 ◽

Vol 52 (Suppl_1) ◽

Author(s):

Aichi Chien ◽

Huy Dinh ◽

Viktor Szeder ◽

Fernando Vinuela

Keyword(s):

Blood Flow ◽

Cerebral Blood Flow ◽

Flow Velocity ◽

Cfd Simulation ◽

Cfd Analysis ◽

Flow Data ◽

Velocity Data ◽

Mean Flow ◽

Good Agreement ◽

Cerebral Vascular

Introduction: Clinical reports show that cerebral blood flow conditions are indicative of cerebral vascular disease. While methods for characterizing cerebral vascular flow have been extensively reported in the past, comparative analyses between direct flow measurements (DM) and computational flow dynamic (CFD) analysis remain limited. We hypothesize that flow data can be reliably measured both directly and through CFD in normal vessels. Methods: A left heart replicator was used as a realistic cardiac pump which maintained systolic pressure at 120 mmHg and diastolic pressure at 80 mmHg. A stenotic model with 50% stenosis for the ICA was connected to the replicator. A ComboWire was used for DM and recorded flow pressure and velocity. CFD was used to study flow. Results: In areas at the proximal end of the stenosis, the pressure and flow velocity derived from DM and CFD were in good agreement. At the end of systole and diastole, DM pressure were 145.42 mmHg and 73.53 mmHg, respectively. CFD simulation for the same system obtained the pressure at the end of systole and diastole of 147.16 mmHg and 74.64 mmHg, respectively. The velocity data collected from DM was at 15.40 cm/s and 7.74 cm/s for systolic flow and mean flow velocity. CFD measured flow was 17.85 cm/s and 11.37 cm/s, respectively. In areas at the distal end of the stenosis, pressure data showed good agreement between DM and CFD analysis. The DM were 138 and 70.81 mmHg at the end of systole and diastole, respectively; CFD simulation yielded 145.95 and 74.51 mmHg, respectively. Variations in the velocity data were observed at this location (Fig, pink arrows). Conclusion: DM of pressure showed good agreement with CFD simulation in all areas of the vessel. DM of velocity using the flow wire were highly affected by location of the measurement. CFD analysis can provide more consistent flow data for flow information collection along the vasculature.

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Repeatability of the Universiti Teknologi MARA reading charts

Bangladesh Journal of Medical Science ◽

10.3329/bjms.v14i3.18964 ◽

2015 ◽

Vol 14 (3) ◽

pp. 236-240 ◽

Cited By ~ 3

Author(s):

Noor Halilah Buari ◽

Nur Hidayah Yusuf ◽

Adib Mohd Satali ◽

Ai Hong Chen

Keyword(s):

Random Sequence ◽

Medical Science ◽

Reading Rate ◽

Read Aloud ◽

Intra Class Correlation ◽

Significant Difference ◽

Good Consistency ◽

Reading Charts ◽

Intra Class Correlation Coefficient ◽

Good Agreement

Objective: This study was done to investigate the repeatability measurements in reading rate using the Universiti Teknologi MARA Malay related words (UiTM-Mrw) reading chart and Universiti Teknologi MARA Malay unrelated words (UiTM-Muw) reading chart. Methodology: Thirty normally sighted participants were randomly recruited through randomised sampling (mean age =21.5±1.1 years). Participants were instructed to read aloud, clearly and as quickly as possible at 2 different sessions using two different charts. The two charts were selected at random sequence. A minimum of 7 days interval was used to minimize the learning affect. The time taken to read each chart was recorded and any errors while reading was noted. Reading performance was quantified as reading rate in words per minute (wpm). Results: Comparison of reading rate between session 1 and session 2 was not significantly different (p=0.894, df=1, F=0.018) for UiTM-Mrw reading chart. The reading rate between session 1 and 2 also showed no significant difference (p=0.99, df=1, F=2.811) in UiTM-Muw reading chart. Intra-class correlation coefficient (ICC) showed a good consistency in repeatability for both UiTM-Mrw reading chart and UiTM-Muw reading chart with ICC values of 0.849 and 0.814 respectively. The Bland and Altman plot between measurement of reading rate in session 1 and session 2 showed a good agreement in UiTM-Mrw reading chart and UiTM-Muw reading chart. Conclusion: Both UiTM-Mrw reading chart and UiTM-Mur reading chart showed a good consistency and good agreement in repeated measurement of reading rate.Bangladesh Journal of Medical Science Vol.14(3) 2015 p.236-240

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A test-retest reliability study of assessing small cutaneous fibers by measuring current perception threshold with pin electrodes

PLoS ONE ◽

10.1371/journal.pone.0242490 ◽

2020 ◽

Vol 15 (11) ◽

pp. e0242490

Author(s):

Weiwei Xia ◽

Han Fu ◽

Haiying Liu ◽

Fanqi Meng ◽

Kaifeng Wang

Keyword(s):

Blood Flow ◽

Quantitative Measurement ◽

Nerve Fibers ◽

Reliability Study ◽

Perception Threshold ◽

Intra Class Correlation ◽

Retest Reliability ◽

Current Perception Threshold ◽

Test Retest Reliability ◽

Intra Class Correlation Coefficient

Background The quantitative measurement of current perception threshold (CPT) has been used as a method to assess the function of nerve fibers in neuropathy diseases. The aim of this study was to assess the test-retest reliability measuring CPT using the circular pin electrodes for assessing the function of cutaneous thin nerve fibers. Methods CPT measurement was repeated on two separate days with at least one-week interval in 55 volunteers. Superficial blood flow (SBF) and skin temperature (ST) were measured on the skin in an around area concentric to the circular pin electrodes after the process of finding CPTs. The coefficient of variation (CV) and intra-class correlation coefficient (ICC) were calculated. The correlation between each two of CPT, SBF increment and ST increment was analyzed. Results No significant differences were found for CPT, SBF and ST between two sessions. SBF was found to be significantly increased after the process of finding CPT. CPT values of males were found to be higher than females. SBF increment was found to be positively correlated with ST increment. The ICC values for CPT, SBF and ST were 0.595, 0.852 and 0.728, respectively. The CV values for CPT, SBF and ST were 25.53%, 12.59% and 1.94%, respectively. Conclusions The reliability of CPT measurement using circular pin electrodes is fair, and need consistence of measurements in longitudinal studies.

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P21.07: Association between uterine artery blood flow volume and fetal weight gain

Ultrasound in Obstetrics and Gynecology ◽

10.1002/uog.18214 ◽

2017 ◽

Vol 50 ◽

pp. 223-224

Author(s):

H. Arneberg ◽

T. Andersen ◽

T. Scholbach ◽

L. Loraas ◽

T.M. Eggebø

Keyword(s):

Blood Flow ◽

Weight Gain ◽

Uterine Artery ◽

Fetal Weight ◽

Flow Volume ◽

Artery Blood Flow ◽

Blood Flow Volume

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Comparison of multi-delay FAIR and pCASL labeling approaches for renal perfusion quantification at 3T MRI

Magnetic Resonance Materials in Physics Biology and Medicine ◽

10.1007/s10334-019-00806-7 ◽

2019 ◽

Vol 33 (1) ◽

pp. 81-94 ◽

Cited By ~ 3

Author(s):

Anita A. Harteveld ◽

Anneloes de Boer ◽

Suzanne Lisa Franklin ◽

Tim Leiner ◽

Marijn van Stralen ◽

...

Keyword(s):

Blood Flow ◽

Arterial Spin Labeling ◽

Spin Labeling ◽

Renal Perfusion ◽

Intra Class Correlation ◽

3T Mri ◽

Perfusion Measurement ◽

Arterial Transit Time ◽

Perfusion Quantification ◽

Intra Class Correlation Coefficient

Abstract Objective To compare the most commonly used labeling approaches, flow-sensitive alternating inversion recovery (FAIR) and pseudocontinuous arterial spin labeling (pCASL), for renal perfusion measurement using arterial spin labeling (ASL) MRI. Methods Multi-delay FAIR and pCASL were performed in 16 middle-aged healthy volunteers on two different occasions at 3T. Relative perfusion-weighted signal (PWS), temporal SNR (tSNR), renal blood flow (RBF), and arterial transit time (ATT) were calculated for the cortex and medulla in both kidneys. Bland–Altman plots, intra-class correlation coefficient, and within-subject coefficient of variation were used to assess reliability and agreement between measurements. Results For the first visit, RBF was 362 ± 57 and 140 ± 47 mL/min/100 g, and ATT was 0.47 ± 0.13 and 0.70 ± 0.10 s in cortex and medulla, respectively, using FAIR; RBF was 201 ± 72 and 84 ± 27 mL/min/100 g, and ATT was 0.71 ± 0.25 and 0.86 ± 0.12 s in cortex and medulla, respectively, using pCASL. For both labeling approaches, RBF and ATT values were not significantly different between visits. Overall, FAIR showed higher PWS and tSNR. Moreover, repeatability of perfusion parameters was better using FAIR. Discussion This study showed that compared to (balanced) pCASL, FAIR perfusion values were significantly higher and more comparable between visits.

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Evaluation of Transabdominal and Transperineal Ultrasound-Derived Prostate Specific Antigen (PSA) Density and Clinical Utility Compared to MRI Prostate Volumes: A Feasibility Study

10.21203/rs.3.rs-1083049/v1 ◽

2021 ◽

Author(s):

Maria Pantelidou ◽

Iztok Caglic ◽

Anne George ◽

Oleg Blyuss ◽

Vincent Gnanapragasam ◽

...

Keyword(s):

Prostate Cancer ◽

Risk Stratification ◽

Specific Antigen ◽

Clinical Decision ◽

Intra Class Correlation ◽

Psa Density ◽

Risk Stratification Tool ◽

Density Values ◽

Intra Class Correlation Coefficient ◽

Good Agreement

Abstract PurposeTo investigate the accuracy of surface-based ultrasound-derived PSA-density (US-PSAD) versus gold-standard MRI-PSAD as a risk-stratification tool. MethodsSingle-centre prospective study of patients undergoing MRI for suspected prostate cancer (PCa). Four combinations of US-volumes were calculated using transperineal (TP) and transabdominal (TA) views, with triplanar measurements to calculate volume and US-PSAD. Intra-class correlation coefficient (ICC) was used tocompare US and MRI volumes. Categorical comparison of MRI-PSAD and US-PSAD was performed at PSAD cut-offs <0.15, 0.15-0.20, and >0.20 ng/mL2 to assess agreement with MRI-PSAD risk-stratification decisions.Results64 men were investigated, mean age 69 years and PSA 7.0 ng/mL. 36/64 had biopsy-confirmed prostate cancer (18 Gleason 3+3, 18 Gleason ≥3+4). Mean MRI-derived gland volume was 60 mL, compared to 56 mL for TA-US, and 65 mL TP-US. ICC demonstrated good agreement for all US volumes with MRI, with highest agreement for transabdominal US, followed by combined TA/TP volumes. Risk-stratification decisions to biopsy showed concordant agreement between triplanar MRI-PSAD and ultrasound-PSAD in 86-91% and 92-95% at PSAD thresholds of >0.15 ng/mL2 and >0.12 ng/mL2, respectively. Biopsy-decision making at threshold >0.12 ng/mL2, demonstrated sensitivity ranges of 81-100%, specificity 85-100%, PPV 86-100% and NPV 83-100%. Transabdominal US provided optimal sensitivity of 100% for this clinical decision, with specificity 85%, and transperineal US provided optimal specificity of 100%, with sensitivity 87%.ConclusionTransperineal-US and combined TA-TP US-derived PSA density values compare well with standard MRI-derived values and could be used to provide accurate PSAD at presentation and inform the need for further investigations.

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Development and Validation of an Instrument to Assess Horseback Mobility in Hippotherapy

Perceptual and Motor Skills ◽

10.1177/00315125211036578 ◽

2021 ◽

pp. 003151252110365

Author(s):

Alessandra V. Prieto ◽

Kênnea Martins Almeida Ayupe ◽

Ana C. A. Abreu ◽

Paulo J. B. Gutierres Filho

Keyword(s):

Correlation Coefficient ◽

Factor Structure ◽

Internal Consistency ◽

Rater Reliability ◽

Intra Class Correlation ◽

Exploratory Factor Analyses ◽

Excellent Internal Consistency ◽

Development And Validation ◽

Functional Gain ◽

Intra Class Correlation Coefficient

Improvement in rider mobility represents an important functional gain for people with disabilities undergoing hippotherapy. However, there is no validated measuring instrument to track and document the rider's progress in riding activities. In this study, we aimed to develop and establish validity evidence for an instrument to assess hippotherapy participants’ mobility on horseback. We report on this development through the stages of: (a) content validation, (b) construct validation, (c) inter- and intra-rater reliability and (d) internal consistency analysis. We evaluated its factor structure with exploratory factor analyses, calculated values for inter- and intra-rater reliability using the intra-class correlation coefficient, and calculated its internal consistency using Cronbach's alpha. We followed recommendations by the Guidelines for Reporting Reliability and Agreement Studies. We found good inter-rater reliability (intra-class correlation coefficient – ICC = 0.991–0.999) and good intra-rater reliability (ICC = 0.997–1.0), and there was excellent internal consistency (Cronbach's α = 0.937–0.999). The instrument’s factor structure grouped its three domains into one factor. As this instrument is theoretically consistent and has been found to be appropriate and reliable for its intended use, it is now available for the measurement of horseback mobility among hippotherapy riders.

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Calculating the optimal hematocrit under the constraint of constant cardiac power

Scientific Reports ◽

10.1038/s41598-021-83427-2 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Michal Sitina ◽

Heiko Stark ◽

Stefan Schuster

Keyword(s):

Blood Flow ◽

High Performance ◽

Animal Species ◽

Normal Values ◽

Mechanical Load ◽

The Body ◽

Trade Off ◽

Cardiac Power ◽

Optimal Value ◽

Good Agreement

AbstractIn humans and higher animals, a trade-off between sufficiently high erythrocyte concentrations to bind oxygen and sufficiently low blood viscosity to allow rapid blood flow has been achieved during evolution. Optimal hematocrit theory has been successful in predicting hematocrit (HCT) values of about 0.3–0.5, in very good agreement with the normal values observed for humans and many animal species. However, according to those calculations, the optimal value should be independent of the mechanical load of the body. This is in contradiction to the exertional increase in HCT observed in some animals called natural blood dopers and to the illegal practice of blood boosting in high-performance sports. Here, we present a novel calculation to predict the optimal HCT value under the constraint of constant cardiac power and compare it to the optimal value obtained for constant driving pressure. We show that the optimal HCT under constant power ranges from 0.5 to 0.7, in agreement with observed values in natural blood dopers at exertion. We use this result to explain the tendency to better exertional performance at an increased HCT.

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Diagnostic accuracy of modified Hadlock formula for fetal macrosomia in women with gestational diabetes and pregnancy weight gain above recommended

Journal of Perinatal Medicine ◽

10.1515/jpm-2021-0013 ◽

2021 ◽

Vol 0 (0) ◽

Author(s):

Boris Lovrić ◽

Siniša Šijanović ◽

Joško Lešin ◽

Josip Juras

Keyword(s):

Weight Gain ◽

Gestational Diabetes ◽

Diagnostic Accuracy ◽

Area Under The Curve ◽

Fetal Weight ◽

Pregnancy Weight Gain ◽

Singleton Pregnancy ◽

Time Period ◽

Modified Formula ◽

Pregnancy Weight

Abstract Objectives Women with gestational diabetes (GDM) and weight gain during pregnancy above recommended more often give birth to macrosomic children. The goal of this study was to evaluate the diagnostic accuracy of the modified formula for ultrasound assessment of fetal weight created in a pilot study using a similar specimen in comparison to the Hadlock-2 formula. Methods This is a prospective, cohort, applicative, observational, quantitative, and analytical study, which included 213 pregnant women with a singleton pregnancy, GDM, and pregnancy weight gain above recommended. Participants were consecutively followed in the time period between July 1st, 2016, and August 31st, 2020. Ultrasound estimations were made within three days before the delivery. Fetal weights estimated using both formulas were compared to the newborns’ weights. Results A total of 133 fetal weight estimations were made. In comparison to the newborns’ weight modified formula had significantly smaller deviation in weight estimation compared to the Hadlock-2 formula, higher frequency of deviation within 5% of newborns weights (78.2% [95% CI=0.74–0.83] vs. 60.2%), smaller frequency of deviations from 5 to 10% (19.5 vs. 33.8%) and above 10%, which was even more significant among macrosomic children. There were 36/50 (72%) correctly diagnosed cases of macrosomia by modified and 33/50 (66%) by Hadlock-2 formula. Area under the curve (AUC) for the modified formula was 0.854 (95% CI=0.776–0.932), and for the Hadlock-2 formula 0.824 (95% CI=0.740–0.908). The positive predictive value of the modified formula was 81.81%, the negative 97.91%. Conclusions In cases of greater fetal weights, the modified formula showed greater precision.

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