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Search Results (213)

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Keywords = pulsatility index

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9 pages, 995 KB  
Case Report
First European Clinical Implant of an Off-the-Shelf Bioengineered Blood Vessel for Coronary Artery Bypass
by Mateusz Kuć, Matthew Soule, Zeeshan Syedain, Abrielle Krouse, Łukasz Wójcik, Monika Chomej-Dąbrowska, Patryk Król and Jerzy Pacholewicz
J. Clin. Med. 2026, 15(8), 3003; https://doi.org/10.3390/jcm15083003 - 15 Apr 2026
Abstract
Background: Coronary artery bypass grafting is the optimal revascularization strategy for patients with complex multivessel coronary artery disease. However, saphenous vein grafts are associated with high failure rates and donor site morbidity. Off-the-shelf tissue-engineered vascular grafts offer a potential solution for patients [...] Read more.
Background: Coronary artery bypass grafting is the optimal revascularization strategy for patients with complex multivessel coronary artery disease. However, saphenous vein grafts are associated with high failure rates and donor site morbidity. Off-the-shelf tissue-engineered vascular grafts offer a potential solution for patients lacking suitable autologous vessels. Here, we report the first successful clinical implant of an acellular Tissue-Engineered Vessel (TEV) for coronary artery bypass grafting in Europe. Methods: A 73-year-old male with two-vessel disease and no suitable autologous vein underwent on-pump coronary artery bypass grafting using the left internal mammary artery to the left anterior descending artery and a 4 mm TEV to the right coronary artery. Results: Implant procedure followed standard surgical techniques, sutures and duration. The conduit handling was comparable to native vessels. Intraoperative flow measurements demonstrated excellent graft performance (TEV: 110 mL/min, Pulsatility Index 1.0). Postoperative recovery was uneventful. One-month computed tomography coronary angiography confirmed graft patency. Discussion: This case demonstrates the feasibility of using a bioengineered conduit for coronary revascularization in patients without suitable autologous grafts. If these findings are confirmed in larger trials, bioengineered vessels could expand surgical revascularization to patients without suitable autologous conduits and fundamentally alter conduit selection strategy in CABG. Conclusions: This first-in-Europe clinical implant demonstrates that an off-the-shelf acellular tissue-engineered vessel can meet the procedural, hemodynamics, and patency requirements of coronary artery bypass. These proof-of-concept results support progression to prospective multi-center evaluation. Full article
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17 pages, 1674 KB  
Article
Evidence That Oscillations in Glucose Metabolism Promote Optimal Islet Function
by Brian P. List, Nicholas B. Whitticar, Kathryn L. Corbin and Craig S. Nunemaker
Metabolites 2026, 16(4), 264; https://doi.org/10.3390/metabo16040264 - 14 Apr 2026
Abstract
Background/Objectives: Impairment in pulsatile insulin release contributes to insulin resistance and is one of the earliest markers of developing type 2 diabetes. Insulin delivered to the liver in pulses has a stronger glucose-lowering effect than continuous insulin delivery. Whether pulsatility benefits the islet [...] Read more.
Background/Objectives: Impairment in pulsatile insulin release contributes to insulin resistance and is one of the earliest markers of developing type 2 diabetes. Insulin delivered to the liver in pulses has a stronger glucose-lowering effect than continuous insulin delivery. Whether pulsatility benefits the islet itself is an open question. We previously showed that reducing glucokinase activity with the glucokinase inhibitor D-mannoheptulose (MH) improves function in islets exposed to prolonged hyperglycemic conditions. In this study, we test whether pulsatile vs. continuous delivery impacts the effectiveness of MH in islets. Methods: Islets were exposed to high-glucose conditions (20 mM glucose) for 24 or 48 h to induce early adaptations to hyperglycemia. We then used a specially designed perifusion system to impose pulsatile activity by exposing mouse islets to 3 min of MH in 20 mM glucose and 3 min of only high levels of glucose. Islets given intermittent MH for 18 h were compared with continuous delivery of MH at a full (2.5 mM) or half (1.25 mM) dose. Results: MH delivered by the forced oscillatory system reversed the effects of hyperglycemia and restored glucose sensing more effectively than continuous delivery. Specifically, fura-2AM imaging of intracellular calcium showed that islets given pulsatile MH had greater reductions in the elevated basal calcium caused by hyperglycemic conditions, improved the glucose stimulation index, and improved phase 0 response (indicating glucose-stimulated calcium uptake by the endoplasmic reticulum). Conclusions: These findings suggest that the loss of oscillatory glucose metabolism in islets contributes directly to beta-cell dysfunction. Full article
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19 pages, 2914 KB  
Article
Patient Image-Based Hemodynamics of Intracranial Aneurysms: An In Silico Study
by Algirdas Maknickas and Jurinda Merkevičiūtė
Appl. Sci. 2026, 16(7), 3233; https://doi.org/10.3390/app16073233 - 27 Mar 2026
Viewed by 248
Abstract
The aim of this research was to calculate hemodynamics of intracaranial aneurysms using computational fluid dynamics. The hemodynamics research of intracranial aneurysms used patient-specific blood pressure data and anonymised DICOM images, from which aneurysm geometries were extracted. The following boundary conditions were established. [...] Read more.
The aim of this research was to calculate hemodynamics of intracaranial aneurysms using computational fluid dynamics. The hemodynamics research of intracranial aneurysms used patient-specific blood pressure data and anonymised DICOM images, from which aneurysm geometries were extracted. The following boundary conditions were established. At the inlet, a pulsatile velocity profile was enforced, and a pressure waveform was assigned at the outlet. Numerical simulations were performed to examine key hemodynamic parameters linked to aneurysm rupture, including wall shear stress, time-averaged wall shear stress, oscillatory shear index, and relative residence time, as well as flow distributions. On the basis of these hemodynamic indicators, the risk of rupture was connected with a geometric property of the aneurysm, the aspect ratio. The hemodynamics parameters obtained ranges with the results of other scientific studies. Finally, it was concluded that combining clinical data, aneurysm geometry, and hemodynamic characteristics can provide clinicians with valuable additional information to use in selection of the appropriate treatment strategy for intracranial aneurysms. Full article
(This article belongs to the Section Biomedical Engineering)
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17 pages, 7795 KB  
Article
Patient-Specific CFD Analysis of Carotid Artery Haemodynamics: Impact of Anatomical Variations on Atherosclerotic Risk
by Abhilash Hebbandi Ningappa, S. M. Abdul Khader, Harishkumar Kamat, Masaaki Tamagawa, Ganesh Kamath, Raghuvir Pai B., Prakashini Koteswar, Irfan Anjum Badruddin, Mohammad Zuber, Kevin Amith Mathias and Gowrava Shenoy Baloor
Computation 2026, 14(4), 77; https://doi.org/10.3390/computation14040077 - 26 Mar 2026
Viewed by 380
Abstract
Understanding the hemodynamics of the carotid artery is essential for assessing atherosclerotic disease progression and identifying regions vulnerable to plaque formation. Background: Disturbed flow patterns and abnormal shear stresses, particularly near the carotid bifurcation, are known to influence endothelial dysfunction; therefore, this study [...] Read more.
Understanding the hemodynamics of the carotid artery is essential for assessing atherosclerotic disease progression and identifying regions vulnerable to plaque formation. Background: Disturbed flow patterns and abnormal shear stresses, particularly near the carotid bifurcation, are known to influence endothelial dysfunction; therefore, this study aims to quantify the impact of patient-specific carotid artery geometry on key hemodynamic parameters associated with atherosclerotic risk. Methods: Four patient-specific carotid artery geometries were reconstructed from medical imaging data, processed using MIMICS, and analyzed using computational fluid dynamics in ANSYS Fluent, with blood modeled as an incompressible non-Newtonian fluid using the Carreau–Yasuda viscosity model under pulsatile flow conditions; velocity streamlines, pressure distribution, time-averaged wall shear stress (TAWSS), and oscillatory shear index (OSI) were evaluated at early systole, peak systole, and peak diastole. Results: The simulations revealed complex flow behaviour, including flow reversal, pressure build-up, and low-shear regions concentrated near the carotid bulb and bifurcation, with TAWSS consistently identifying low-shear zones (<1 Pa) across all geometries and OSI exhibiting pronounced directional oscillations in models with increased curvature and wider bifurcation angles. Conclusions: These findings demonstrate that geometric characteristics such as bifurcation angle, vessel tortuosity, and asymmetry play a critical role in shaping local haemodynamics, underscoring the utility of patient-specific CFD analysis as a diagnostic and predictive tool for atherosclerotic risk assessment and supporting more informed, personalized clinical decision-making. Full article
(This article belongs to the Section Computational Engineering)
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10 pages, 2114 KB  
Article
Choroidal Thickening and Reduced Macular Blood Flow in Children with Hyperopic Anisometropic Amblyopia
by Ryuya Hashimoto, Juri Kawamura, Naoki Fujioka, Kazufumi Tanaka, Moe Nunose, Sara Imai, Serika Moriyama, Ryo Yamazaki, Asato Hirota and Fumihiko Yagi
J. Clin. Med. 2026, 15(5), 2085; https://doi.org/10.3390/jcm15052085 - 9 Mar 2026
Viewed by 279
Abstract
Background/Objectives: This study aimed to evaluate macular choroidal blood flow dynamics and structural alterations in children with hyperopic anisometropic amblyopia and compare these findings with those of the fellow eyes. Methods: This retrospective observational study included 36 eyes from 18 children (mean age: [...] Read more.
Background/Objectives: This study aimed to evaluate macular choroidal blood flow dynamics and structural alterations in children with hyperopic anisometropic amblyopia and compare these findings with those of the fellow eyes. Methods: This retrospective observational study included 36 eyes from 18 children (mean age: 4.9 years) with unilateral hyperopic anisometropic amblyopia. Central choroidal thickness (CCT) was measured using enhanced depth imaging optical coherence tomography. Macular choroidal hemodynamics were assessed using laser speckle flowgraphy. Mean blur rate (MBR) was used as an index of blood flow, whereas beat strength (BS) was used as a measure of pulsatility. Ocular perfusion pressure (OPP) was also calculated. All parameters were compared between amblyopic and fellow eyes. Results: Amblyopic eyes demonstrated significantly greater CCT compared with fellow eyes (407.6 ± 84.9 µm vs. 326.4 ± 79.1 µm). Conversely, macular MBR was significantly lower in amblyopic eyes (9.28 ± 3.60 AU vs. 10.94 ± 4.68 AU), as was BS (5.73 ± 3.07 AU vs. 7.28 ± 3.59 AU). No significant differences were observed in central retinal thickness or OPP between amblyopic and fellow eyes. In amblyopic eyes, CCT was not significantly correlated with macular MBR or BS. Conclusions: Amblyopic eyes exhibited significant central choroidal thickening accompanied by reduced macular blood flow and pulsatility. These findings suggest that localized macular hemodynamic dysregulation may contribute to the pathophysiology of hyperopic anisometropic amblyopia. Full article
(This article belongs to the Special Issue Progress in Clinical Diagnosis and Therapy in Ophthalmology)
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15 pages, 710 KB  
Article
An Assessment of the Effect of HIV and ART on Cardiovascular Risk Factors to Predict Retinal Microvascular Impairment in Pregnant Women: A Pilot Study in a South African Population
by Edna N. Matjuda, Benedicta N. Nkeh-Chungag, Godwill A. Engwa, Constance R. Sewani-Rusike, Nontsikelelo C. Gubu-Ntaba, Charles B. Businge, Adam Saloň, Patrick De Boever and Nandu Goswami
J. Vasc. Dis. 2026, 5(2), 12; https://doi.org/10.3390/jvd5020012 - 28 Feb 2026
Viewed by 406
Abstract
Background: Human immunodeficiency virus (HIV) and antiretroviral therapy (ART) are known to be involved in cardiovascular disease development. They act alongside systemic risk factors, which interact with both macrovascular and microvascular vessels to accelerate vascular damage. Therefore, the aim of this study was [...] Read more.
Background: Human immunodeficiency virus (HIV) and antiretroviral therapy (ART) are known to be involved in cardiovascular disease development. They act alongside systemic risk factors, which interact with both macrovascular and microvascular vessels to accelerate vascular damage. Therefore, the aim of this study was to investigate the cardiovascular risk factors and their relationship with retinal microvascular function in HIV-positive pregnant women on ART in Mthatha, South Africa. Methods: A cross-sectional study was carried out among 78 pregnant women (25 HIV-positive and 53 HIV-negative) in Mthatha, South Africa. Blood pressure (BP) parameters, including systolic BP (SBP), diastolic BP (DBP), and heart rate (HR), were measured, and mean arterial pressure (MAP) was calculated. Lipid profile parameters and fasting blood glucose were assessed. Markers for kidney function, such as albuminuria, were determined. Vascular biomarkers including asymmetric dimethyl arginine (ADMA) and human endothelial specific molecule-1 were quantified. Non-invasive vascular function parameters such as flow-mediated slowing (FMS), carotid-femoral pulse wave velocity (cfPWV), ankle-brachial index, central retinal arteriolar equivalent (CRAE), central retinal venular equivalent (CRVE), arteriolar venular ratio (AVR), uterine artery pulsatile index (UtA PI) were determined. Results: Diastolic BP, MAP, cfPWV, ADMA, low density lipoprotein (LDL-c) and UtA PI were higher in the HIV-positive group (p ≤ 0.05) compared to the HIV-negative group. The prevalence of prehypertension/hypertension was higher in the HIV-positive group (p ≤ 0.05). DBP, MAP, and cfPWV correlated positively with CRVE in the HIV-positive group (p ≤ 0.05), while AVR negatively correlated with the urinary creatinine (uCr) in the same group (p ≤ 0.05). Linear regression results demonstrated that DBP, cfPWV, ABI, and LDL-c were predictors of reduced AVR in the HIV-positive group. Conclusions: Increased cardiovascular risk was observed in HIV-positive pregnant women on ART. Further, increased cardiovascular risk such as hypertension and endothelial dysfunction due to ART predicted retinal microvascular dysfunction in the HIV-positive population. This implies a potential mechanistic link between macrovascular dysfunction due to cardiovascular risk factors and retinal microvascular impairment, highlighting the importance of assessing cardiovascular risk early and preserving overall vascular health in HIV-positive population. Full article
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13 pages, 1592 KB  
Article
Umbilical Coiling Index, Doppler Parameters, and Cord Blood Gas Analysis: Lack of Correlation in Uncomplicated Term Pregnancies
by Zeynep Begum Celik, Gulseren Dinc, Suleyman Caner Karahan, Sumeyye Sura Ayan and Suleyman Guven
J. Clin. Med. 2026, 15(5), 1810; https://doi.org/10.3390/jcm15051810 - 27 Feb 2026
Viewed by 291
Abstract
Background/Objectives: In this study, we aimed to evaluate whether neonatal ischemia-modified albumin (IMA) and umbilical venous cord blood gas parameters are associated with antenatal markers of fetal well-being, including the umbilical coiling index (UCI) and umbilical artery (UA) and middle cerebral artery [...] Read more.
Background/Objectives: In this study, we aimed to evaluate whether neonatal ischemia-modified albumin (IMA) and umbilical venous cord blood gas parameters are associated with antenatal markers of fetal well-being, including the umbilical coiling index (UCI) and umbilical artery (UA) and middle cerebral artery (MCA) Doppler indices. Methods: For this prospective observational study, sixty-five low-risk term pregnancies (≥37 weeks) were included. Prenatal ultrasound was used to measure the UCI and UA/MCA Doppler indices. At delivery, umbilical venous cord blood gas and serum IMA analyses were performed. Maternal and neonatal data (birth weight, 5 min Apgar score, NICU admission, sex, and delivery mode) were recorded, and correlations and group comparisons were performed (p < 0.05). Results: The UCI ranged from 0.210 to 0.471 coil/cm (mean 0.337). The UA and MCA Doppler indices were within the reference ranges. The UCI showed no significant correlation with umbilical venous blood gas values, IMA, UA/MCA Doppler indices, gestational age/weeks, or 5 min Apgar score. The UA S/D ratio and UA resistive index (RI) were negatively correlated with birth weight (p < 0.05). Umbilical venous pH was positively correlated with the 5 min Apgar score, whereas venous pCO2 was negatively correlated with the 5 min Apgar score (both p < 0.05). Newborns with venous pH < 7.32 had higher cesarean delivery rates and higher rooming-in rates. Newborns admitted to the NICU had higher mean UA systolic velocity/diastolic velocity (S/D) and UA pulsatility index (PI) and lower venous pH. Conclusions: In low-risk term pregnancies, the UCI was not associated with cord blood gas parameters, IMA, or UA/MCA Doppler indices. These results suggest that the UCI may have limited clinical utility as a predictor of early neonatal acidosis or oxidative stress in a strictly low-risk population. Full article
(This article belongs to the Section Obstetrics & Gynecology)
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19 pages, 6201 KB  
Article
Transcranial Doppler Pulsatility Index and MRI Findings in Meningoencephalitis: A Pilot Observational Retrospective Cohort Study in Critically Ill Patients
by Maria Grazia Bocci, Giulia Capecchi, Antonio Lesci, Dorotea Rubino, Ilaria Caravella, Giorgia Taloni, Valerio Sabatini, Candido Porcelli, Giulia Valeria Stazi, Gabriele Garotto, Elena Mattiucci, Emanuele Nicastri, Tommaso Ascoli Bartoli, Gaetano Maffongelli, Emiliano Cingolani, Fabrizio Albarello, Giulia Anello, Paolo Campioni, Stefania Ianniello and Daniele Guerino Biasucci
Clin. Pract. 2026, 16(2), 41; https://doi.org/10.3390/clinpract16020041 - 14 Feb 2026
Viewed by 392
Abstract
Background: Meningoencephalitis is a complex inflammatory condition of the CNS that can result in significant morbidity and mortality in critically ill adults. Accurate and timely neuromonitoring is essential for guiding management and improving outcomes. This study aimed to descriptively evaluate the prognostic value [...] Read more.
Background: Meningoencephalitis is a complex inflammatory condition of the CNS that can result in significant morbidity and mortality in critically ill adults. Accurate and timely neuromonitoring is essential for guiding management and improving outcomes. This study aimed to descriptively evaluate the prognostic value of early TCCD monitoring, particularly the pulsatility index, and its integration with conventional and perfusion MRI in patients with meningoencephalitis. Methods: We present an observational, retrospective, cohort study involving ten adult patients (median age 56 years, IQR 45.5–68.5; mean 55.9, range 35–76) with neurological syndromes caused by suspected or confirmed infectious meningoencephalitis. Etiologies included bacterial meningitis/meningoencephalitis (50%), viral meningoencephalitis (10%), neurotoxoplasmosis (10%), progressive multifocal leukoencephalopathy (10%), and undetermined origin (20%). Patients underwent TCCD and MRI within 24 h. In five cases, standard MRI sequences were acquired, while in the remaining five, perfusion imaging was performed using Arterial Spin Labelling (ASL). A favorable outcome was defined as survival with neurological recovery (Glasgow Outcome Scale > 5) at ICU discharge. Results: TCCD-derived PI provided valuable information on cerebral hemodynamics. PI values ≤ 1.25 were associated with favorable clinical outcomes and symmetrical MRI findings. Conversely, PI > 1.25 correlated with poor prognosis and often preceded MRI-detectable structural damage. When combined with ASL, PI mirrored the detected perfusion asymmetries and was associated with poor prognosis in fatal cases. Conclusions: Bedside TCCD can offer real-time assessment of cerebrovascular dynamics and, when integrated with conventional and ASL MRI, could enhance the understanding of pathophysiological processes in meningoencephalitis, supporting timely and informed decisions in neurocritical care. Full article
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9 pages, 218 KB  
Article
Fetal Adrenal Gland Biometry and Middle Adrenal Artery Doppler in Pregnancies Presenting with Preterm Labor: A Prospective Case–Control Study
by Belgin Savran Üçok, Özgür Volkan Akbulut, Sadun Sucu, Mustafa Bağcı, İbrahim Buğra Bahadır and Kadriye Yakut Yücel
J. Clin. Med. 2026, 15(3), 1192; https://doi.org/10.3390/jcm15031192 - 3 Feb 2026
Viewed by 346
Abstract
Objective: This study aimed to compare fetal adrenal gland volume (AGV), fetal zone (FZ) depth, and middle adrenal artery pulsatility index (MAA-PI) between pregnancies presenting with preterm labor and gestational age-matched asymptomatic controls, and to evaluate size-adjusted adrenal metrics (corrected AGV [cAGV] [...] Read more.
Objective: This study aimed to compare fetal adrenal gland volume (AGV), fetal zone (FZ) depth, and middle adrenal artery pulsatility index (MAA-PI) between pregnancies presenting with preterm labor and gestational age-matched asymptomatic controls, and to evaluate size-adjusted adrenal metrics (corrected AGV [cAGV] and fetal zone–total gland depth ratio) in relation to gestational age at delivery and neonatal outcomes. Methods: This prospective analytical cross-sectional (case–control) study included 60 singleton pregnancies (30 with preterm labor and 30 asymptomatic controls) evaluated at a tertiary perinatology unit between 24 + 0 and 36 + 6 weeks’ gestation. Transvaginal cervical length and transabdominal fetal adrenal measurements (AGV, FZ depth, and MAA-PI) were obtained at enrollment. Estimated fetal weight (EFW) at the index scan was retrieved, and corrected AGV (cAGV = AGV/EFW) and fetal zone–total gland depth ratio were calculated. Outcomes were gestational age at delivery, birthweight, Apgar scores, and neonatal intensive care unit (NICU) admission. Nonparametric group comparisons and Spearman correlations were used. Results: Gestational age at ultrasound was identical between groups (median 31 + 6 weeks). Compared with controls, the preterm labor group had shorter cervical length (12.5 vs. 33.5 mm, p < 0.001), higher AGV (1.53 vs. 1.08 cm3, p < 0.001) and FZ depth (7.45 vs. 5.30 mm, p < 0.001), and lower MAA-PI (1.11 vs. 1.46, p < 0.001). EFW at the index scan did not differ between groups (p = 0.900). Corrected AGV (cAGV) was higher in the preterm labor group (0.87 (0.76–1.06) vs. 0.59 (0.51–0.70), p < 0.001), and the fetal zone–total gland depth ratio was higher (0.328 (0.312–0.346) vs. 0.263 (0.241–0.278), p < 0.001). The preterm labor group delivered earlier (33 + 0 vs. 36 + 2 weeks, p < 0.001), had lower birthweight (1875 vs. 3188 g, p < 0.001), and more frequent NICU admission (50.0% vs. 6.7%; odds ratio 14.0, 95% CI 2.82–69.56; p < 0.001). Within the preterm labor group, gestational age at delivery correlated positively with cervical length (ρ = 0.900) and MAA-PI (ρ = 0.770) and negatively with AGV (ρ = −0.770) and FZ depth (ρ = −0.733), all p < 0.001; correlations were stronger for cAGV (ρ = −0.953, p < 0.001). Conclusions: Enlarged fetal adrenal gland volume and fetal zone depth together with reduced middle adrenal artery pulsatility index are associated with preterm labor and earlier delivery. Size-adjusted adrenal metrics (cAGV and fetal zone–total gland depth ratio) remained significantly different between groups, supporting these measures as potential adjuncts for risk stratification at presentation. Full article
(This article belongs to the Section Obstetrics & Gynecology)
24 pages, 11871 KB  
Article
MCV-Driven Effective Viscosity Modulation and Its Hemodynamic Impact in an Idealized Carotid Bifurcation: A Computational Fluid Dynamics Study
by Arif Çutay, Hakan Bayrakcı, Özdeş Çermik and Muharrem İmal
Fluids 2026, 11(2), 40; https://doi.org/10.3390/fluids11020040 - 29 Jan 2026
Viewed by 443
Abstract
Mean corpuscular volume (MCV) is a routinely measured hematological parameter that influences blood viscosity by altering red blood cell volume and packing density. Although MCV is physiologically linked to hemorheological behavior, to the authors’ knowledge, its direct [...] Read more.
Mean corpuscular volume (MCV) is a routinely measured hematological parameter that influences blood viscosity by altering red blood cell volume and packing density. Although MCV is physiologically linked to hemorheological behavior, to the authors’ knowledge, its direct role in modulating large-artery hemodynamics has not been systematically quantified. This study introduces an MCV-driven effective Newtonian viscosity mode to evaluate the first-order impact of MCV variation on carotid bifurcation flow. Rather than employing shear-dependent constitutive laws, blood viscosity was scaled through an MCV-based formulation, yielding three Newtonian fluids corresponding to clinically relevant MCV levels of 70, 90, and 110 fL. Pulsatile CFD simulations were performed in four idealized carotid bifurcation geometries (40°, 50°, 65°, and 100°) to assess the combined influence of vascular geometry and MCV-dependent viscosity variation. Hemodynamic indices including time-averaged wall shear stress (TAWSS), oscillatory shear index (OSI), and relative residence time (RRT) were quantified, and a two-way analysis of variance (ANOVA) was employed to distinguish the relative contributions of geometric configuration and MCV. Across the investigated MCV range, increasing MCV produced a geometry-dependent modulation of shear-based indices, with TAWSS increasing by up to approximately 11%, while OSI and RRT decreased by about 20–25% and 10%, respectively, particularly in geometries exhibiting pronounced flow separation. Although vascular geometry remained the dominant determinant of overall hemodynamic patterns, MCV-induced viscosity scaling significantly modulated low-shear and recirculation regions. These findings suggest that MCV-dependent viscosity scaling can complement patient-specific hemodynamic assessments and provide a rational baseline for future shear-dependent and personalized rheological modeling frameworks. Full article
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13 pages, 515 KB  
Article
Foramen Ovale Measurements and Venous Hemodynamic Changes Assessed by Inferior Vena Cava Doppler Parameters in Early- and Late-Onset Fetal Growth Restriction
by Merve Ayas Ozkan, Halis Doğukan Ozkan, Ruken Dayanan, Hilal Sarı, Furkan Akın, Gülşah Dağdeviren and Ali Turhan Çağlar
J. Clin. Med. 2026, 15(3), 980; https://doi.org/10.3390/jcm15030980 - 26 Jan 2026
Viewed by 310
Abstract
Background: Fetal growth restriction (FGR) is a major contributor to adverse perinatal outcomes and is primarily driven by placental insufficiency and chronic fetal hypoxia. While arterial Doppler abnormalities are widely used in clinical surveillance, less is known about venous hemodynamics and intracardiac [...] Read more.
Background: Fetal growth restriction (FGR) is a major contributor to adverse perinatal outcomes and is primarily driven by placental insufficiency and chronic fetal hypoxia. While arterial Doppler abnormalities are widely used in clinical surveillance, less is known about venous hemodynamics and intracardiac structural adaptations in FGR. In particular, the clinical relevance of foramen ovale (FO) morphometry and inferior vena cava (IVC) Doppler parameters in different FGR phenotypes remains incompletely understood. This study aimed to evaluate FO measurements and IVC Doppler indices in early- and late-onset FGR and to investigate their associations with adverse perinatal outcomes. Methods: This prospective observational study included 240 singleton pregnancies: 120 fetuses with FGR and 120 gestational age-matched appropriate-for-gestational-age controls. FGR was defined according to Delphi consensus criteria and classified as early onset (<32 weeks) or late onset (≥32 weeks). Ultrasonographic assessment included FO and right atrium dimensions, FO-to-right atrium (FO/RA) ratio, IVC diameter, and IVC Doppler indices (pulsatility index [PI], preload index [PLI], and peak velocity index for veins [PVIV]). A composite adverse perinatal outcome (CAPO) was recorded. Receiver operating characteristic (ROC) curve analysis and multivariable logistic regression were performed. Results: Compared with controls, fetuses with FGR exhibited significantly smaller FO dimensions, lower FO/RA ratios, reduced IVC diameters, and higher IVC Doppler indices (all p < 0.05). The FO/RA ratio demonstrated the highest discriminative performance for CAPO (AUC 0.722). In multivariable analysis, a 0.1-unit increase in the FO/RA ratio was independently associated with a reduced risk of CAPO (OR 0.57), whereas higher IVC PI values were associated with an increased risk (OR 2.64). IVC Doppler alterations were less pronounced in early-onset FGR. Conclusions: FO morphometry and IVC Doppler parameters reflect complementary stages of fetal cardiovascular adaptation in fetal growth restriction, with FO changes representing early adaptive responses and IVC Doppler alterations indicating more advanced hemodynamic compromise, and this may provide additional value for perinatal risk stratification. Full article
(This article belongs to the Section Obstetrics & Gynecology)
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13 pages, 1044 KB  
Review
The Role of Ophthalmic Artery Doppler in Predicting Preeclampsia: A Review of the Literature
by Nicoleta Gana, Ancuța Năstac, Livia Mihaela Apostol, Iulia Huluță, Corina Gica, Gheorghe Peltecu and Nicolae Gica
Medicina 2026, 62(1), 186; https://doi.org/10.3390/medicina62010186 - 16 Jan 2026
Viewed by 836
Abstract
Background and Objectives: Preeclampsia (PE) complicates 2–8% of pregnancies globally, with a higher incidence in developing countries. This condition poses significant risks to maternal and fetal health, contributing substantially to maternal and perinatal mortality, particularly in cases of early-onset PE, which is associated [...] Read more.
Background and Objectives: Preeclampsia (PE) complicates 2–8% of pregnancies globally, with a higher incidence in developing countries. This condition poses significant risks to maternal and fetal health, contributing substantially to maternal and perinatal mortality, particularly in cases of early-onset PE, which is associated with severe complications. This review aims to synthesize current evidence regarding the predictive utility of ophthalmic artery Doppler for preeclampsia. Current strategies focus on early prediction and prevention to mitigate adverse outcomes and reduce the economic burden of hypertensive disorders in pregnancy. The International Federation of Gynecology and Obstetrics (FIGO) recommends first-trimester screening combining maternal risk factors, mean arterial pressure, serum placental growth factor (PlGF), and uterine artery pulsatility index (UtA-PI). High-risk women are advised to take low-dose aspirin (150 mg daily) until 36 weeks of gestation. Materials and Methods: This review explores an innovative predictive tool for PE: ophthalmic artery (OA) Doppler. Results: As a non-invasive and easily accessible method, OA Doppler provides valuable insights into intracranial vascular resistance, offering potential advantages in early risk assessment, particularly for preterm PE, the most severe form of the disease. Conclusions: Our findings suggest that OA Doppler may serve as a promising adjunct in PE screening, enhancing the early identification of high-risk pregnancies and improving clinical outcomes. Further research is warranted to validate its role in routine prenatal care. Full article
(This article belongs to the Special Issue Advances in Reproductive Health)
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15 pages, 632 KB  
Article
Predictive Accuracy of Ultrasound Biometry and Maternal Factors in Identifying Large-for-Gestational-Age Neonates at 30–34 Weeks
by Vasileios Bais, Antigoni Tranidou, Antonios Siargkas, Sofoklis Stavros, Anastasios Potiris, Dimos Sioutis, Chryssi Christodoulaki, Apostolos Athanasiadis, Apostolos Mamopoulos, Ioannis Tsakiridis and Themistoklis Dagklis
Diagnostics 2026, 16(2), 187; https://doi.org/10.3390/diagnostics16020187 - 7 Jan 2026
Viewed by 672
Abstract
Background/Objectives: To construct and compare multivariable prediction models for the early prediction of large-for-gestational-age (LGA) neonates, using ultrasound biometry and maternal characteristics. Methods: This retrospective cohort study analyzed data from singleton pregnancies that underwent routine ultrasound examinations at 30+0–34+0 [...] Read more.
Background/Objectives: To construct and compare multivariable prediction models for the early prediction of large-for-gestational-age (LGA) neonates, using ultrasound biometry and maternal characteristics. Methods: This retrospective cohort study analyzed data from singleton pregnancies that underwent routine ultrasound examinations at 30+0–34+0 weeks of gestation. Ultrasound parameters included fetal abdominal circumference (AC), head circumference (HC), femur length (FL), HC-to-AC ratio, mean uterine artery pulsatility index (mUtA-PI), and presence of polyhydramnios. LGA neonates were defined as those having a birthweight > 90th percentile. Logistic regression was used to evaluate associations between ultrasound markers and LGA after adjusting for the following maternal and pregnancy-related covariates: maternal age, body mass index, parity, gestational diabetes mellitus (GDM), pre-existing diabetes, previous cesarean section (PCS), assisted reproductive technology (ART) use, smoking, hypothyroidism, and chronic hypertension. Associations were expressed as adjusted odds ratios (aORs) with 95% confidence intervals (CIs). Three prognostic models were developed utilizing the following predictors: (i) biometric ultrasound measurements including AC, HC-to-AC ratio, FL, UtA-PI, and polyhydramnios (Model 1), (ii) a combination of biometric ultrasound measurements and clinical–maternal data (Model 2), and (iii) only the estimated fetal weight (EFW) (Model 3). Results: In total, 3808 singleton pregnancies were included in the analyses. The multivariable analysis revealed that AC (aOR 1.07, 95% CI [1.06, 1.08]), HC to AC (aOR 1.01, 95% CI [1.006, 1.01]), FL (aOR 1.01, 95% CI [1.009, 1.01]), and the presence of polyhydramnios (aOR 4.97, 95% CI [0.7, 58.8]) were associated with an increased risk of LGA, while a higher mUtA-PI was associated with a reduced risk (aOR 0.98, 95% CI [0.98, 0.99]). Maternal parameters, such as GDM, pre-existing diabetes, elevated pre-pregnancy BMI, absence of uterine artery notching, mUtA-PI, and multiparity, were significantly higher in the LGA group. Both models 1 and 2 showed similar performance (AUCs: 84.7% and 85.3%, respectively) and outperformed model 3 (AUC: 77.5%). Bootstrap and temporal validation indicated minimal overfitting and stable model performance, while decision curve analysis supported potential clinical utility. Conclusions: Models using biometric and Doppler ultrasound at 30–34 weeks demonstrated good discriminative ability for predicting LGA neonates, with an AUC up to 84.7%. Adding maternal characteristics did not significantly improve performance, while the biometric model performed better than EFW alone. Sensitivity at conventional thresholds was low but increased substantially when lower probability cut-offs were applied, illustrating the model’s threshold-dependent flexibility for early risk stratification in different clinical screening needs. Although decision curve analysis was performed to explore potential clinical utility, external validation and prospective assessment in clinical settings are still needed to confirm generalizability and to determine optimal decision thresholds for clinical application. Full article
(This article belongs to the Special Issue Advances in Ultrasound Diagnosis in Maternal Fetal Medicine Practice)
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19 pages, 1204 KB  
Review
Fetal Hepatic Circulation: From Vascular Physiology to Doppler Assessment
by Inês Gil-Santos and Luís Guedes-Martins
Diagnostics 2025, 15(24), 3147; https://doi.org/10.3390/diagnostics15243147 - 10 Dec 2025
Viewed by 980
Abstract
During fetal life, the hepatic artery (HA) is responsible for a small contribution to the total hepatic blood inflow; however, it plays a key role in maintaining liver perfusion and reflects fetal hemodynamic adaptation. With advances in ultrasonography, HA Doppler assessment has emerged [...] Read more.
During fetal life, the hepatic artery (HA) is responsible for a small contribution to the total hepatic blood inflow; however, it plays a key role in maintaining liver perfusion and reflects fetal hemodynamic adaptation. With advances in ultrasonography, HA Doppler assessment has emerged as a potential tool for evaluating fetal well-being. This review aims to synthesize current knowledge on the embryology, anatomy, physiology, and Doppler assessment of the fetal hepatic artery, highlighting its diagnostic and clinical significance. A prenatal hepatic arterial buffer response (HABR), analogous to that in postnatal life, allows for compensatory vasodilatation when umbilical or portal venous inflow decreases. Doppler studies demonstrate that a reduced pulsatility index (PI) and resistance index (RI) and an increased peak systolic velocity (PSV) correspond to enhanced arterial flow and decreased vascular resistance. These patterns have been observed in fetal growth restriction (FGR) and certain chromosomal abnormalities. Fetal hepatic artery Doppler assessment contributes to the understanding of fetal adaptation to hypoxia and has a promising role in fetal well-being evaluation. As of now, there are no established reference curves, and it has not yet been incorporated into routine obstetric screening; future research should focus on standardizing measurement techniques and validating its prognostic value. Full article
(This article belongs to the Section Medical Imaging and Theranostics)
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11 pages, 539 KB  
Article
Insights into the Hepatic Arterial Buffer Response in Late-Onset FGR
by Aziz Kından, Can Ozan Ulusoy, Aykut Kından, Tuğçe Sırma, Aşkın Evren Güler, İsmail Burak Gültekin and Zehra Vural Yılmaz
J. Clin. Med. 2025, 14(23), 8403; https://doi.org/10.3390/jcm14238403 - 27 Nov 2025
Viewed by 577
Abstract
Objective: To evaluate hepatic artery Doppler parameters in fetuses with fetal growth restriction (FGR) and to investigate their relationship with composite adverse neonatal outcomes (CANO). Methods: This prospective cohort study included 108 pregnancies (54 FGR; 54 appropriate-for-gestational-age controls) between 34 and 37 weeks’ [...] Read more.
Objective: To evaluate hepatic artery Doppler parameters in fetuses with fetal growth restriction (FGR) and to investigate their relationship with composite adverse neonatal outcomes (CANO). Methods: This prospective cohort study included 108 pregnancies (54 FGR; 54 appropriate-for-gestational-age controls) between 34 and 37 weeks’ gestation. Hepatic artery (HA), umbilical artery (UA), middle cerebral artery (MCA), and uterine artery Doppler indices were recorded. Logistic regression and ROC analyses were used to determine predictors of FGR and CANO. Results: HA pulsatility index (PI), systolic/diastolic ratio, and peak systolic velocity (PSV) were significantly higher in FGR fetuses (p < 0.05). In multivariate regression, HA-PI remained independently associated with FGR (aOR 1.74, 95% CI 1.07–2.87, p = 0.025). For predicting CANO, HA-PSV was the only independent predictor (aOR 1.05, 95% CI 1.00–1.10, p = 0.020). ROC analysis demonstrated moderate discriminative ability for HA-PI (AUC 0.681) and HA-PSV (AUC 0.703). Conclusions: Increased HA-PSV in FGR reflects activation of the hepatic arterial buffer response as an adaptive mechanism to maintain hepatic perfusion under hypoxic stress, whereas elevated HA-PI may represent evolving microvascular resistance. Hepatic artery Doppler evaluation may serve as a complementary tool for assessing fetal well-being and identifying fetuses at risk for adverse neonatal outcomes, particularly in late-onset FGR. Full article
(This article belongs to the Section Obstetrics & Gynecology)
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