Changes In Perfusion Research Articles

MR Assessment of Acute Changes of Cerebral Perfusion, Metabolism, and Blood-Brain Barrier Permeability in Response to Aerobic Exercise.

It remains unclear how a single bout of exercise affects brain perfusion, oxygen metabolism, and blood-brain barrier (BBB) permeability. Addressing this unresolved issue is essential to understand the acute changes in cerebral physiology induced by aerobic exercise. To dynamically monitor the acute changes in cerebral physiology subsequent to a single aerobic exercise training session using noninvasive MRI measurements. Prospective. Twenty-three healthy participants (18-35 years, 10 females/13 males) were enrolled and divided into 10-minute exercising (N = 10) and 20-minute exercising (N = 13) groups. 3.0 T/Phase Contrast (PC) MRI (gradient echo), T2-Relaxation-Under-Spin-Tagging (TRUST) MRI (gradient echo EPI), Water-Extraction-with-Phase-Contrast-Arterial-Spin-Tagging (WEPCAST) MRI (gradient echo EPI) and T1-weighted magnetization-prepared-rapid-acquisition-of-gradient-echo (MPRAGE) (gradient echo). A baseline MR measurement plus four repeated MR measurements immediately after 10 or 20 minutes moderate running exercise. MR measurements included cerebral blood flow (CBF) as measured by PC MRI, venous oxygenation (Yv) and cerebral metabolic rate of oxygen (CMRO2) as assessed by TRUST MRI, water extraction fraction (E), and BBB permeability-surface-area product (PS) as determined by WEPCAST MRI. The time dependence of the physiological parameters was studied with a linear mixed-effect model. Additionally, pairwise t-tests comparison of the physiological parameters at each time point was conducted. A P-value of <0.05 was considered statistically significant. There was an initial drop (8.22 ± 2.60%) followed by a recovery in CBF after exercise, while Yv revealed a significant decrease (6.37 ± 0.92%), i.e., an increased oxygen extraction, and returned to baseline at later time points. CMRO2 showed a trend of increase (5.68 ± 3.04%) and a significant interaction between time and group. In addition, E increased significantly (3.86% ± 0.89) and returned to baseline level at later time points, while PS remained elevated (13.33 ± 4.79%). A single bout of moderate aerobic exercise can induce acute alterations in cerebral perfusion, metabolism, and BBB permeability. 2 TECHNICAL EFFICACY: Stage 2.

Standardized evaluation methodology for renal cortical blood perfusion in elderly patients using contrast‐enhanced ultrasound: A Chinese expert consensus (2024 edition)

AbstractAs a sensitive and non‐invasive method for assessing changes in renal cortical blood perfusion in the elderly, contrast‐enhanced ultrasound (CEUS) can indirectly reflect changes in kidney filtration and reabsorption function, thus providing feasibility for early evaluation of renal function changes. However, significant differences exist among researchers in terms of operational methods, contrast agent selection, post‐data analysis, and many other aspects, leading to substantial heterogeneity in results. This hinders horizontal comparisons and greatly limits the clinical application of contrast‐enhanced ultrasound for evaluating renal cortical blood flow perfusion. Based on the latest domestic and overseas literature and discussions with clinical experts, this consensus provides recommended guidelines for the evaluation of renal cortical blood flow perfusion using contrast‐enhanced ultrasound. It is hoped that this consensus will promote a better understanding of CEUS among medical practitioners at all levels and standardize the examination of renal cortical blood flow perfusion with CEUS.

Power-Doppler Ultrasonic Imaging of Peripheral Perfusion in Diabetic Mice.

We explored the capabilities of power-Doppler ultrasonic (PD-US) imaging without contrast enhancement for monitoring changes in muscle perfusion over time. Ischemic recovery was observed in healthy and type II diabetic male and female mice with and without exercise. In separate studies, perfusion was measured during and after 5-min ischemic periods and during four-week recovery periods following irreversible femoral ligation. A goal was to assess how well PD-US estimates tracked the diabetic-related changes in endothelial function that influenced perfusion. The average perfusion recovery time following femoral ligation increased 47% in diabetic males and 74% in diabetic females compared with non-diabetic mice. Flow-mediated dilation in conduit arteries and the reactive hyperemia index in resistive vessels each declined by one half in sedentary diabetic mice compared with sedentary non-diabetic mice. We found that exercise reduced the loss of endothelial function from diabetes in both sexes. The reproducibility of perfusion measurements was limited primarily by our ability to select the same region in muscle and to effectively filter tissue clutter. PD-US measurements can precisely follow site-specific changes in skeletal muscle perfusion related to diabetes over time, which fills the need for techniques capable of regularly monitoring atherosclerotic changes leading to ischemic vascular pathologies.

Real-time monitoring of middle cerebral artery blood flow using intraoperative transcranial doppler during trans-carotid artery revascularization

ObjectiveTranscarotid artery revascularization (TCAR) has emerged as a safe and effective method for carotid revascularization, offering several key advantages over carotid endarterectomy (CEA) and carotid artery stenting (CAS). Intraoperative transcranial Doppler (TCD) monitoring plays a pivotal role in assessing cerebral hemodynamics and detecting embolic signals during TCAR at our institution. MethodsThis review synthesizes the current literature and provides guidance for TCD monitoring throughout the various phases of TCAR, from preoperative assessment to postoperative management. Key considerations include probe placement, waveform evaluation, interpreting monitoring parameters such as mean flow velocity (MFV), pulsatility index (PI), and percentage change in the MFV (Δ%). Techniques for maintaining the insonation of the middle cerebral artery (MCA) M1 segment and optimal parameter settings for intraoperative TCD monitoring are detailed. ResultsTCAR phases are highlighted, including transcarotid access and vessel control, sheath insertion, the establishment of flow reversal, pre-dilation, stent placement, post-dilation, and closure, while emphasizing the importance of real-time feedback provided by TCD monitoring in identifying embolic signals and assessing changes in cerebral perfusion. The review discusses limitations of TCD monitoring, such as inadequate temporal windows, incorrect vessel identification and reliability issues with automatic emboli detection counters. Furthermore, practical advice is provided on how to navigate common pitfalls encountered during intraoperative TCD monitoring. ConclusionBy understanding the nuances of TCD monitoring and its application in TCAR, intraoperative TCD monitoring may aid to minimize the low but potential risk of intraprocedural embolic events, periprocedural hypoperfusion and postoperative hyperperfusion. Finally, we suggest opportunities for further research in embolization quantification and additional strategies to optimize quality control in TCAR.

Needle-free jet injector treatment with bleomycin is efficacious in patients with severe keloids: a randomized, double-blind, placebo-controlled trial.

Severe keloids are difficult to treat. Corticosteroid injections with needles are painful and associated with frequent recurrences. Therefore, more effective, safe and patient friendly alternative treatments are urgently needed. To assess the efficacy, tolerability, and patient satisfaction of intralesional bleomycin treatment using a needle-free electronic pneumatic jet injector (EPI) in severe keloids. Patients with severe keloids were included in this double-blind, randomized placebo-controlled trial with split-lesion design. Three EPI treatments with bleomycin or saline, were administered every four weeks in respectively the intervention and control side. Outcome measures were change in scar volume assessed by 3D-imaging, Patient and Observer Scar Assessment Scale (POSAS), skin perfusion with laser speckle contrast imaging (LSCI), spilled volume, procedure related pain, adverse events, and patient satisfaction. Fourteen patients (9 female, 5 men) were included. The estimated mean keloid volume was significantly reduced with 20% after EPI-assisted bleomycin, compared to a slight increase of 3% in the control side (p<0.01). The estimated mean POSAS patient and observer scores decreased with respectively 26% and 28% (p = 0.02; p = 0.03). LSCI showed no significant change in perfusion. EPI treatment was preferred over previous needle injections in 85% of patients. The estimated mean spilled volume after EPI was around 50%, and NRS pain scores were moderate. Adverse events included bruising, hyperpigmentation, and transient superficial necrosis. Three EPI-assisted bleomycin treatments are efficacious and well-tolerated in severe keloids. Moreover, EPI treatment was preferred by most patients and may serve as a patient-friendly alternative treatment.

Colorimetric Analyses of the Optic Nerve Head and Retina Indicate Increased Blood Flow After Vitrectomy.

The purpose of this study was to evaluate the impact of vitrectomy and posterior hyaloid (PH) peeling on color alteration of optic nerve head (ONH) and retina as a surrogate biomarker of induced perfusion changes. Masked morphometric and colorimetric analyses were conducted on preoperative (<1month) and postoperative (<18months) color fundus photographs of 54 patients undergoing vitrectomy, either with (44) or without (10) PH peeling and 31 years of age and gender-matched control eyes. Images were calibrated according to the hue and saturation values of the parapapillary venous blood column. Chromatic spectra of the retinal pigment epithelium and choroid were subtracted to avoid color aberrations. Red, green, and blue (RGB) bit values over the ONH and retina were plotted within the constructed RGB color space to analyze vitrectomy-induced color shift. Vitrectomy-induced parapapillary vein caliber changes were also computed morphometrically. A significant post-vitrectomy red hue shift was noted on the ONH (37.1degrees ± 10.9degrees vs. 4.1degrees ± 17.7degrees, P < 0.001), which indicates a 2.8-fold increase in blood perfusion compared to control (2.6 ± 1.9 vs. 0.9 ± 1.8, P < 0.001). A significant post-vitrectomy increase in the retinal vein diameter was also noticed (6.8 ± 6.4% vs. 0.1 ± 0.3%, P < 0.001), which was more pronounced with PH peeling (7.9 ± 6.6% vs. 3.1 ± 4.2%, P = 0.002). Vitrectomy and PH peeling increase ONH and retinal blood flow. Colorimetric and morphometric analyses offer valuable insights for future artificial intelligence and deep learning applications in this field. The methodology described herein can easily be applied in different clinical settings and may enlighten the beneficial effects of vitrectomy in several retinal vascular diseases.

Plasma as endothelial rescue in septic shock: A randomized, phase 2a pilot trial.

Septic shock is associated with high morbidity and mortality, the endothelium plays an important role. Crystalloids is standard of care to maintain intravascular volume. Plasma is associated with improved endothelial integrity and restoration of the glycocalyx layer. We evaluated the efficacy and safety aspects of cell-free and pathogen inactivated pooled plasma (OctaplasLG®) as resuscitation in septic shock patients. This randomized, investigator-initiated phase IIa trial ran at a Danish single center intensive care unit, from 2017 to 2019. Patients were 18 years of age or older with septic shock and randomized to fluid optimization with OctaplasLG® or Ringer-acetate in the first 24 h. The primary endpoints were changes in biomarkers indicative of endothelial activation, damage, and microvascular perfusion from baseline to 24 h. Safety events and mortality were assessed during 90 days. Forty-four patients were randomized, 20 to OctaplasLG versus 24 to Ringer-acetate. The median age was 69, and 55% were men. Median Sequential Organ Failure Assessment score was 13. Baseline differences favoring the Ringer-acetate group were observed. The OctaplasLG® group was resuscitated with 740 mL plasma and the Ringer-acetate group with 841 mL crystalloids. There was no significant change in the microvascular perfusion or five biomarkers except VEGFR1 change, which was higher in patients receiving OctaplasLG® 0.12(SD 0.37) versus Ringer-acetate -0.24 (SD 0.39), with mean difference 0.36 (95% CI, 0.13-0.59, p = .003) in favor of Ringer-acetate. This study found that fluid resuscitation with OctaplasLG® in critically ill septic shock patients is feasible. Baseline confounding prevented assessment of the potential effect of OctaplasLG®.

Non-contrast quantitative study of brain perfusion changes in multiple sclerosis

Non-contrast quantitative study of brain perfusion changes in multiple sclerosis

Unveiling the role of dorsal root ganglia in spasticity reduction: Insights from contralateral seventh cervical nerve cross transfer surgery.

Central nervous system (CNS) disorders, such as stroke, often lead to spasticity, which result in limb deformities and significant reduction in quality of life. Spasticity arises from disruptions in the normal functioning of cortical and descending inhibitory pathways in the brainstem, leading to abnormal muscle contractions. Contralateral seventh cervical nerve cross transfer (CC7) surgery has been proven to effectively reduce spasticity, but the specific mechanism for its effectiveness is unclear. This study aimed to investigate the changes in the dorsal root ganglia (DRG) following CC7 surgery. A comprehensive anatomical analysis was conducted through cadaveric study and magnetic resonance imaging (MRI) study, to accurately measure the regional anatomy of the C7 DRG. DRG perfusion changes were quantitatively assessed by comparing pre- and postoperative dynamic contrast-enhanced (DCE) MRI. In CC7 surgery, the C7 nerve root on the affected side is cut close to the DRG (3.6±1.0mm), while the C7 nerve root on the healthy side is cut further away from the DRG (65.0±10.0mm). MRI studies revealed that after C7 proximal neurotomy on the affected side, there was an increase in DRG volume, vascular permeability, and perfusion; after C7 distal neurotomy on the healthy side, there was a decrease in DRG volume, with no significant changes in vascular permeability and perfusion. This study provides preliminary insights into the mechanisms of spasticity reduction following CC7 surgery, indicating that changes in the DRG, such as increased vascular permeability and perfusion, could disrupt abnormal spinal γ-circuits. The resulting high-perfusion state of DRG, possibly due to heightened neuronal activity and metabolic demands, necessitating further research to verify this hypothesis.

Myocardial perfusion improvement and mechanism after percutaneous intramyocardial septal radiofrequency ablation in obstructive hypertrophic cardiomyopathy: a study of myocardial contrast echocardiography.

The data on myocardial perfusion of the percutaneous intramyocardial septal radiofrequency ablation (PIMSRA) for obstructive hypertrophic cardiomyopathy (HOCM) are still lacking, although PIMSRA have been proved to be of great safety and efficacy. The aim of this study was to quantitatively analyze the changes in myocardial perfusion after PIMSRA using myocardial contrast echocardiography (MCE). 27 HOCM patients treated with PIMSRA were retrospectively analyzed, and their echocardiographic parameters and perfusion parameters of MCE were collected before and 12 months after PIMSRA. A reperfusion curve was used to quantify microvascular blood volume (A), microvascular flux rate (β), and microvascular blood flow (MBF) of each segment. Then the value difference (Δ) of parameters between post- and pre-operation were calculated. Finally, the correlation between the changes in MBF and in each echocardiographic parameter was analyzed. (1) Compared with baseline, the global A, β and MBF were significantly increased in HOCM patients after PIMSRA (all P < 0.001). The β, MBF were increased in the interventricular septum (P < 0.001, respectively), and the A, β, MBF were increased in the left ventricular wall (all P < 0.001). (2) Correlation analysis showed that the ΔMBF of interventricular septum was mainly negatively correlated with the maximum interventricular septum thickness (ΔIVSTmax, r=-0.670, P < 0.001), mean interventricular septum thickness (ΔIVSTmean, r=-0.690, P < 0.001), and left ventricular mass index (ΔLVMI, r=-0.774, P < 0.001), while the ΔMBF of left ventricular wall was positively correlated with left ventricular end-diastolic volume index (ΔLVEDVI, r = 0.621, P = 0.001) and stroke volume index (ΔSVI, r = 0.810, P < 0.001). Myocardial perfusion was improved at both interventricular septum and ventricular wall in HOCM patients after PIMSRA. MCE can provide a new dimension for the efficacy evaluation to PIMSRA procedure.

Resting-state neural activity and cerebral blood flow alterations in type 2 diabetes mellitus: Insights from hippocampal subfields.

In this study, multimodal magnetic resonance imaging (MRI) imaging was used to deeply analyze the changes of hippocampal subfields perfusion and function in patients with type 2 diabetes mellitus (T2DM), aiming to provide image basis for the diagnosis of hippocampal-related nerve injury in patients with T2DM. We recruited 35 patients with T2DM and 40 healthy control subjects (HCs). They underwent resting-state functional MRI (rs-fMRI), arterial spin labeling (ASL) scans, and a series of cognitive tests. Then, we compared the differences of two groups in the cerebral blood flow (CBF) value, amplitude of low-frequency fluctuation (ALFF) value, and regional homogeneity (ReHo) value of the bilateral hippocampus subfields. The CBF values of cornu ammonis area 1 (CA1), dentate gyrus (DG), and subiculum in the right hippocampus of T2DM group were significantly lower than those of HCs. The ALFF values of left hippocampal CA3, subiculum, and bilateral hippocampus amygdala transition area (HATA) were higher than those of HCs in T2DM group. The ReHo values of CA3, DG, subiculum, and HATA in the left hippocampus of T2DM group were higher than those of HCs. In the T2DM group, HbAc1 and FINS were negatively correlated with imaging characteristics in some hippocampal subregions. This study indicates that T2DM patients had decreased perfusion in the CA1, DG, and subiculum of the right hippocampus, and the right hippocampus subiculum was associated with chronic hyperglycemia. Additionally, we observed an increase in spontaneous neural activity within the left hippocampal CA3, subiculum, and bilateral HATA regions, as well as an enhanced local neural coordination in the left hippocampal CA3, DG, HATA, and subiculum among patients with type 2 diabetes, which may reflect an adaptive compensation for cognitive decline. However, this compensation may decline with the exacerbation of metabolic disorders.

Simultaneous visualization of changes in perfusion and myocardial function of a transplanted heart in emergency cardiology

Introduction. In conditions of the Emergency Cardiology Department, a timely and differential diagnosis of myocardial pathology is especially important in the absence of visible focal changes and significant coronary artery stenosis. This group of patients includes recipients of a transplanted heart, when it is difficult to count on the high sensitivity of perfusion images alone. This can be explained by the diffuse, balanced distribution of ischemia.Objective. To present the possibilities of perfusion myocardial single photon emission computed tomography synchronized with electrocardiography for a detailed assessment of the functional condition of both ventricles of the transplanted heartMaterial and methods. We have presented three clinical case reports of the patients with different pathology of the transplanted heart who referred themselves to the emergency cardiology clinic and underwent electrocardiographysynchronized perfusion myocardial single photon emission computed tomography for diagnostic purposes.Results. In all the cases presented, the radionuclide study influenced making the diagnosis and changing the treatment tactics. In the first case, it was possible to identify focal myocardial changes, for which coronary angiography and percutaneous coronary intervention with thromboextraction were immediately performed. In the second case, the image analysis reflecting the function of the myocardium (polar maps of wall movement and systolic thickening) allowed us to note a low efficacy of treatment for the transplanted heart rejection. In the third clinical case, the initial single photon emission computed tomography suggested the inflammatory nature of changes in the myocardium, which was verified by the results of endomyocardial biopsy.Conclusion. In the presented clinical cases, the urgently performed electrocardiography-synchronized perfusion myocardial single photon emission computed tomography made it possible to perform invasive interventions in time and thereby contribute to the recovery of the graft functional state and patient's condition improvement.

Insomnia in patients with MRI-negative epilepsy: The associated factors and 3D-pCASL cerebral blood flow perfusion changes

ObjectiveThis study aimed to identify the factors associated with insomnia in MRI-negative epilepsy and uncover the underlying pathological mechanism driving insomnia within the context of epilepsy. MethodsWe conducted a retrospective study of patients with MRI-negative epilepsy recruited consecutively from December 2021 to December 2022. All subjects completed the Insomnia Severity Index (ISI), Epworth Sleepiness Scale (ESS), Self-rating Anxiety Scale (SAS), and Self-rating Depression Scale (SDS). Additionally, some subjects underwent the three-dimensional pseudo continuous arterial spin labeling(3D-pCASL) imaging examination. Bilateral frontal lobe, temporal lobe, hippocampus, thalamus, amygdala, caudate nucleus and lenticular nucleus were selected as regions of interest(ROI) and cerebral blood flow(CBF) values were measured in these regions. Subjects were classified into insomnia (ISI ≥ 10) or non-insomnia (ISI < 10) groups, and univariate and stepwise logistic regression analyses were employed to identify the factors associated with insomnia. Furthermore, CBF values in each ROI were compared between the two groups to identify the brain regions potentially related to the underlying pathological mechanism of insomnia in epilepsy. ResultsA total of 73 patients with MRI-negative epilepsy were recruited in this study(men, 49.3 %). Among them, 14 patients(19.2 %) had insomnia. Univariate regression revealed that nocturnal seizures, number of anti-seizure medication(ASM), anxiety, use of valproic acid(VPA), depression, and excessive daytime sleepiness(EDS) may be associated with insomnia in MRI-negative epilepsy (all p＜0.05). Stepwise regression demonstrated that nocturnal seizures, anxiety, and EDS were independently associated with insomnia in MRI-negative epilepsy (OR[95 %CI]P: 14.64[2.02–106.27]0.008,49.35[3.06–796.61]0.006, 13.28[1.25–140.66]0.032, respectively). Furthermore, CBF values in the left amygdala were significantly lower in patients with MRI- negative epilepsy who had insomnia. ConclusionThe prevalence of insomnia in MRI-negative epilepsy is 19.2%. Nocturnal seizures, anxiety, and EDS were independently associated with insomnia in MRI-negative epilepsy. The noteworthy decrease in CBF values in the left amygdala might be connected to the underlying pathological mechanism of insomnia in epilepsy.

Indocyanine Green Angiography for Detecting Quantitative Perfusion Changes in Deep Inferior Epigastric Perforator Flap Breast Reconstruction With Second Venous Drainage.

This study aims to compare perfusion dynamics using indocyanine green videoangiography before and after the creation of a second venous anastomosis between the superficial inferior epigastric vein and the retrograde internal mammary vein (IMV) in deep inferior epigastric perforator (DIEP) flap breast reconstructions. Indocyanine green videoangiography performed during DIEP flap reconstructions was analyzed prospectively. The areas of interest were above the perforators with the highest intensity (complete perfusion), the most distal lateral edge of the flap (partial perfusion), and the next lowest intensity (ischemic). We compared the zone intensities before and after the second venous anastomosis, assessing venous drainage patency and functionality. Patient characteristics, operative details, and complications were collected. Seven patients (10 breasts) underwent DIEP reconstruction. Mean age was 54.5 ± 12.4 years. Mean operative duration was 575.5 ± 172.6 minutes. Donors included DIEV (n = 10, 100.0%), superficial inferior epigastric vein (n = 9, 90.0%), and superficial circumflex epigastric vein (n = 1, 10.0%). All DIEVs were anastomosed to the antegrade IMV (n = 10, 100.0%). Superficial inferior epigastric veins were anastomosed to the retrograde IMV (n = 10, 100.0%). Mean peak intensities of the complete perfusion zone before and after the second venous anastomosis were 160.7 ± 42.1 and 188 ± 42.1, respectively ( P = 0.163). Mean peak intensities of the partial perfusion zone were 100.8 ± 21.5 and 152 ± 31.5, respectively ( P < 0.001). Mean peak intensities of the ischemic zone were 90.4 ± 37.4 and 143.4 ± 45.3, respectively ( P = 0.012). These findings highlight the potential benefits of the super drainage technique in enhancing perfusion and reducing complications, emphasizing the need for further investigation and consideration of this technique in clinical practice.

A novel NIR-II albumin-escaping probe for cerebral arteries and perfusion imaging in stroke mice model

In order to guide the formulation of post-stroke treatment strategy in time, it is necessary to have real-time feedback on collateral circulation and revascularization. Currently used near-infrared II (NIR-II) probes have inherent binding with endogenous albumin, resulting in significant background signals and uncontrollable pharmacokinetics. Therefore, the albumin-escaping properties of the new probe, IR-808AC, was designed, which achieved timely excretion and low background signal, enabling the short-term repeatable injection for visualization of cerebral vessels and perfusion. We further achieved continuous observation of changes in collateral vessels and perfusion during the 7-d period in middle cerebral artery occlusion mice using IR-808AC in vivo. Furthermore, using IR-808AC, we confirmed that remote ischemic conditioning could promote collateral vessels and perfusion. Finally, we evaluated the revascularization after thrombolysis on time in embolic stroke mice using IR-808AC. Overall, our study introduces a novel methodology for safe, non-invasive, and repeatable assessment of collateral circulation and revascularization in real-time that is crucial for the optimization of treatment strategies.

Ferumoxytol-enhanced MRI assessment of venous Thrombus resolution and macrophage content in a murine deep vein thrombosis model

BackgroundImaging evaluation of acute deep vein thrombosis (DVT) or post-thrombotic syndrome (PTS) in animal or clinical models is limited to anatomical assessment of the location and extent of thrombi. We hypothesize that Fe-MRI, used to evaluate macrophage content in other inflammatory diseases, can be useful to evaluate the thromboinflammatory features after DVT over time. MethodsNineteen wild-type CD-1 mice underwent surgical IVC ligation to induce DVT. Mice received either saline or 5 mg/kg of 14E11, a Factor XI inhibitor, before the procedure. Fe-MRI was performed on days 6–7 after ligation to evaluate thrombus volume, perfusion, and macrophage content via T2-weighted images. Mice were euthanized at days 3–15 after surgery. The thrombi and adjacent vein walls were excised, weighed, formalin-fixed, and paraffin-embedded for immunohistological analysis. Specimens were stained with specific antibodies to evaluate macrophage content, collagen deposition, neovascularization, and recanalization. Significance was determined using the Mann-Whitney U or Student's t-test. ResultsAfter IVC-ligation in control mice, thrombus weights decreased by 59 % from day 3 to 15. Thrombus volumes peaked on day 5 before decreasing by 85 % by day 13. FXI inhibition led to reduced macrophage content in both thrombi (p = .008) and vein walls (p = .01), decreased thrombus volume (p = .03), and decreased thrombus mass (p = .01) compared to control mice. CCR2+ staining corroborated these findings, showing significantly reduced macrophage presence in the thrombi (p = .002) and vein wall (p = .002). ConclusionsFe-MRI T2 relaxation times can be used to characterize and quantify post-thrombotic changes of perfusion, macrophage content, and thrombus volume over time in a surgical mouse model of venous thrombosis. This approach could lead to better quantification of in vivo inflammation correlating monocyte and macrophage content within resolving thrombi and veins and may serve as a useful tool for research and clinically in the evaluation of the post-thrombotic environment.

Noninvasive Real-Time Assessment of Nipple-Areola Complex Perfusion Using Laser Speckle Contrast Imaging in Direct-to-Implant Breast Reconstruction.

Nipple-areola complex (NAC) necrosis is a major complication for breast reconstruction after nipple-sparing mastectomy. Although intraoperative indocyanine green angiography helps to assess the viability of tissue, the imaging could be conservative which may lead to aggressive resection. The plastic surgeons are eager to know the perfusion changes of NAC throughout the perioperative period. In this prospective cohort study, the authors enrolled patients who underwent NSM and immediate direct-to-implant breast reconstruction. All patients underwent laser speckle contrast imaging before surgery, immediately after mastectomy, after implant placement, and 24h and 72h after surgery. A total of 94 breasts were analyzed, including 64 breasts healed with viable NAC and 30 breasts with NAC necrosis. In viable NACs, the average blood supply decreased to 56% after NSM and 42% after reconstruction, then recovered to 68% and 80% at 24-h and 72-h post-operation. In necrotic NACs, the average blood supply decreased to 33% after NSM and 24% after reconstruction, and partial perfusion recovery was also recorded at 24-h (31%) and 72-h (37%) post-operation. The cutoff value for predicting NAC viability is 40% after NSM and 25% after implant placement. The study quantified the NAC perfusion changes during the perioperative period. NAC perfusion decreased significantly after NSM and would be the lowest after the end of breast reconstruction. Viable NACs displayed more perfusion during the operation and showed significant nipple revascularization after breast reconstruction. This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Perfusion increase in foot angiosomes: Comparison between direct and indirect revascularization of crural arteries.

In retrospective studies, wound healing and leg salvage have been better if revascularization is targeted to the crural artery supplying arterial flow to the wound angiosome. No data exist on how revascularization changes the blood flow in foot angiosomes. The aim of this study was to evaluate the change in perfusion after infrapopliteal artery revascularization in all foot angiosomes and to compare directly revascularized (DR) angiosomes to the indirectly revascularized (IR) angiosomes. In this prospective study, foot perfusion was measured with indocyanine green fluorescence imaging (ICG-FI) before and after either surgical or endovascular below-knee revascularization. According to angiograms, we divided the foot angiosomes into DR and IR angiosomes. Furthermore, in a subanalysis, the IR angiosomes were graded as IR_Coll+ angiosomes if there were strong collaterals arising from the artery which was revascularized, and as IR_Coll- angiosomes if strong collaterals were not seen. A total of 72 feet (28 bypass, 44 endovascular revascularizations) and 282 angiosomes were analyzed. Surgical and endovascular revascularization increased perfusion significantly in both DR and IR angiosomes. After bypass surgery, the increase in DR angiosomes was 55 U and 53 U in IR angiosomes; there were no significant difference in the perfusion increase between IR and DR angiosomes. After endovascular revascularization, perfusion increased significantly more, 40 U, in DR angiosomes compared to 26 U in IR angiosomes (p < 0.05). In the subanalysis of IR angiosomes, perfusion increased significantly after surgical bypass regardless of whether strong collaterals were present or not. After endovascular revascularization, however, a significant perfusion increase was noted in the IR_Coll+ but not in the IR_Coll- subgroup. Open revascularization increased perfusion equally in DR and IR angiosomes, whereas endovascular revascularization increased perfusion significantly more in DR than in IR angiosomes. Strong collateral network may help increase perfusion in IR angiosomes.

Imaging in Interventional Radiology: Applications of Contrast-Enhanced Ultrasound.

This review explores the applications of contrast-enhanced ultrasound (CEUS) in interventional radiology, focusing on its role in endoleak detection after endovascular abdominal aortic aneurysm repair (EVAR), periprocedural thermal ablation guidance, and transarterial chemoembolization (TACE) for hepatocellular carcinoma (HCC). CEUS offers a dynamic assessment for the detection of endoleak following EVAR, facilitating accurate diagnosis and classification. In periprocedural thermal ablation, CEUS enhances target lesion delineation with the visualization of real-time perfusion changes, optimizing treatment strategies and reducing residual tumor rates. Finally, CEUS has demonstrated efficacy in intraprocedural evaluation and postprocedural follow-up in TACE for HCC, offering early detection of residual tumor enhancement and providing an alternative for patients with contraindications to contrast-enhanced computed tomography or magnetic resonance imaging. Overall, CEUS is a versatile and valuable tool with many applications to offer interventional radiologists enhanced diagnostic capabilities and improved patient management.

Effects of diet-induced metabolic syndrome on cardiac function and angiogenesis in response to the sodium-glucose cotransporter-2 inhibitor canagliflozin

IntroductionSodium-glucose cotransporter-2 inhibitors are antidiabetic medications that have been shown to decrease cardiovascular events and heart failure-related mortality in clinical studies. We attempt to examine the complex interplay between metabolic syndrome and the sodium-glucose cotransporter-2 inhibitor canagliflozin (CAN) in a clinically relevant model of chronic myocardial ischemia. MethodsTwenty-one Yorkshire swine were fed a high-fat diet starting at 6 weeks of age to induce metabolic syndrome. At 11 weeks, all underwent placement of an ameroid constrictor around the left circumflex coronary artery to induce chronic myocardial ischemia. After 2 weeks, swine received either control (CON) (n = 11) or CAN 300 mg by mouth daily (n = 10) for 5 weeks, whereupon all underwent terminal harvest. ResultsThere was a significant increase in cardiac output and heart rate with a decrease in pulse pressure in the CAN group compared with CON (all P values < .05). The CAN group had a significant increase in capillary density (P = .02). There was no change in myocardial perfusion or arteriolar density. CAN induced a significant increase in markers of angiogenesis, including Phospho-endothelial nitric oxide synthase, Endothelial nitric oxide synthase, vascular endothelial growth factor receptor-1, heat shock protein 70, and extracellular signal-regulated kinases (all P values < .05), plausibly resulting in capillary angiogenesis. ConclusionsCAN treatment leads to a significant increase in capillary density and augmented cardiac function in a swine model of chronic myocardial ischemia in the setting of metabolic syndrome. This work further elucidates the mechanism of sodium-glucose cotransporter-2 inhibitors in patients with cardiac disease; however, more studies are needed to determine if this increase in capillary density plays a role in the improvements seen in clinical studies.