Futile recanalization in patients with basilar artery occlusion: assessment of the underlying etiology and the role of perfusion imaging.

BACKGROUND: Futile recanalization (FR) after endovascular therapy (EVT) is common in basilar artery occlusion (BAO). The purpose of this study was to investigate the predictors of FR in the posterior circulation with an emphasis on the role of perfusion imaging and its relation to the underlying etiology. METHODS: We included BAO patients who had pretreatment perfusion imaging and successful recanalization after EVT. Patients were dichotomized into futile and non-futile groups according to the favorable functional outcome at 90 days (modified Rankin Scale (mRS) 0-3). Perfusion abnormalities were assessed using an automated software for Tmax volume measurement and identification of hypoperfusion area based on Tmax>6 s involvement of the pons-midbrain-thalamus (PMT), cerebellum, and temporo-occipital lobe. RESULTS: Of the 134 enrolled patients, the incidence of FR was 47.8% (64/134). Multivariate logistic analysis showed that a higher National Institutes of Health Stroke Scale (NIHSS) score on admission (adjusted OR (aOR) 1.066; 95% CI 1.011 to 1.125), a longer onset-to-recanalization time (aOR 1.002; 95% CI 1.001 to 1.004), incomplete recanalization (aOR 3.909; 95% CI 1.498 to 10.200), and PMT hypoperfusion (aOR 4.444; 95% CI 1.203 to 16.415) were independent predictors of FR. In patients with embolic occlusion of etiology, PMT hypoperfusion was associated with FR (aOR 8.379; 95% CI 1.377 to 50.994), whereas intracranial atherosclerotic stenosis (ICAS)-related occlusion was not (p=0.587). CONCLUSIONS: In patients with BAO, the likelihood of FR is associated with PMT hypoperfusion on pretreatment perfusion imaging. In particular, PMT hypoperfusion may be used as an imaging predictor of FR in patients with embolic cause of BAO.

Distinctive protein expression in elderly livers in a Sprague-Dawley rat model of normothermic ex vivo liver machine perfusion.

BACKGROUND: Liver grafts are frequently declined due to high donor age or age mismatch with the recipient. To improve the outcome of marginal grafts, we aimed to characterize the performance of elderly vs. young liver grafts in a standardized rat model of normothermic ex vivo liver machine perfusion (NMP). METHODS: Livers from Sprague-Dawley rats aged 3 or 12 months were procured and perfused for 6 h using a rat NMP system or collected as a reference group (n = 6/group). Tissue, bile, and perfusate samples were used for biochemical, and proteomic analyses. RESULTS: All livers cleared lactate during perfusion and continued to produce bile after 6 h of perfusion (614 mg/h). Peak urea levels in 12-month-old animals were higher than in younger animals. Arterial and portal venous pressure, bile production and pH did not differ between groups. Proteomic analysis identified a total of 1477 proteins with oxidoreductase and catalytic activity dominating the gene ontology analysis. Proteins such as aldehyde dehydrogenase 1A1 and 2-Hydroxyacid oxidase 2 were significantly more present in livers of older age. CONCLUSIONS: Young and elderly liver grafts exhibited similar viability during NMP, though proteomic analyses indicated that older grafts are less resilient to oxidative stress. Our study is limited by the elderly animal age, which corresponds to mature but not elderly human age typically seen in marginal human livers. Nevertheless, reducing oxidative stress could be a promising therapeutic target in the future.

Diagnostic Algorithm for Intracranial Lesions in the Emergency Department: Effectiveness of the Relative Brain Volume and Hounsfield Unit Value Measured by Perfusion Tomography.

Background Early treatment of intracranial lesions in the emergency department is crucial, but it can be challenging to differentiate between them. This differentiation is essential because the treatment of each type of lesion is different. Cerebral computed tomography perfusion (CTP) imaging can help visualize the vascularity of brain lesions and provide absolute quantification of physiological parameters. Compared to magnetic resonance imaging, CTP has several advantages, such as simplicity, wide availability, and reproducibility. Purpose This study aimed to assess the effectiveness of Hounsfield units (HU) in measuring the density of hypercellular lesions and the ability of CTP to quantify hemodynamics in distinguishing intracranial space-occupying lesions. Methods A retrospective study was conducted from March 2016 to March 2022. All patients underwent CTP and CT scans, and relative cerebral blood volume (rCBV) and HU were obtained for intracranial lesions. Results We included a total of 244 patients in our study. This group consisted of 87 (35.7%) individuals with glioblastomas (GBs), 48 (19.7%) with primary central nervous system lymphoma (PCNSL), 45 (18.4%) with metastases (METs), and 64 (26.2) with abscesses. Our study showed that the HUs for METs were higher than those for GB (S 57.4% and E 88.5%). In addition, rCBV values for PCNSL and abscesses were lower than those for GB and METs. The HU in PCNSL was higher than those in abscesses (S 94.1% and E 96.6%). Conclusion PCT parameters provide valuable information for diagnosing brain lesions. A comprehensive assessment improves accuracy. Combining rCBV and HU enhances diagnostic accuracy, making it a valuable tool for distinguishing between lesions. PCT's widespread availability allows for the use of both anatomical and functional information with high spatial resolution for diagnosing and managing brain tumor patients.

Outcomes in Patients with Heel Ulcerations that Underwent Below the Knee Amputations versus Vertical Contour Calcanectomy: Importance of Selection Criteria.

The aim of the study was to compare preoperative factors and postoperative outcomes in patients with heel ulcerations that primarily had a transtibial (below the knee) amputation (N=38) versus vertical contour calcanectomy (n=62). The groups had no statistical difference between their Charlson Comorbidity Index Score, a prognostic score of ten-year survival in patients with multiple comorbidities. The odds of primary closure was 21.1 times higher in patients that underwent below knee amputation compared to patients that underwent vertical contour calcanectomy [OR 21.1 (95% CI 3.89-114.21)]. The odds of positive soft tissue culture at time of closure were 17.1 times higher for patients that underwent vertical contour calcanectomy [OR 17.1 (95% CI 5.40-54.16)]. The odds of a patent posterior tibial artery was 3.3 times higher for patients that underwent vertical contour calcanectomy [OR 3.3 (95% 1.09-10.09)]. The secondary aim of the study was to evaluate preoperative factors and postoperative outcomes in patients with failed vertical contour calcanectomy, defined as needing a below knee amputation. The odds of vertical contour calcanectomy failure was 13.7 times higher in male patients [OR 13.7 (95% CI 1.80-107.60)]. Vertical contour calcanectomy failure was 5.7 times higher in patients with renal disease [OR 5.7 (95% CI 1.10-30.30)], and vertical contour calcanectomy failure was 16.1 times higher for patients who needed additional surgery post closure [OR 16.1 (95% CI 1.40-183.20)].

Deep learning-based segmentation of left ventricular myocardium on dynamic contrast-enhanced MRI: a comprehensive evaluation across temporal frames.

PURPOSE: Cardiac perfusion MRI is vital for disease diagnosis, treatment planning, and risk stratification, with anomalies serving as markers of underlying ischemic pathologies. AI-assisted methods and tools enable accurate and efficient left ventricular (LV) myocardium segmentation on all DCE-MRI timeframes, offering a solution to the challenges posed by the multidimensional nature of the data. This study aims to develop and assess an automated method for LV myocardial segmentation on DCE-MRI data of a local hospital. METHODS: The study consists of retrospective DCE-MRI data from 55 subjects acquired at the local hospital using a 1.5 T MRI scanner. The dataset included subjects with and without cardiac abnormalities. The timepoint for the reference frame (post-contrast LV myocardium) was identified using standard deviation across the temporal sequences. Iterative image registration of other temporal images with respect to this reference image was performed using Maxwell's demons algorithm. The registered stack was fed to the model built using the U-Net framework for predicting the LV myocardium at all timeframes of DCE-MRI. RESULTS: The mean and standard deviation of the dice similarity coefficient (DSC) for myocardial segmentation using pre-trained network Net_cine is 0.78 ± 0.04, and for the fine-tuned network Net_dyn which predicts mask on all timeframes individually, it is 0.78 ± 0.03. The DSC for Net_dyn ranged from 0.71 to 0.93. The average DSC achieved for the reference frame is 0.82 ± 0.06. CONCLUSION: The study proposed a fast and fully automated AI-assisted method to segment LV myocardium on all timeframes of DCE-MRI data. The method is robust, and its performance is independent of the intra-temporal sequence registration and can easily accommodate timeframes with potential registration errors.

Perfusion deficits may underlie lung and kidney injury in severe COVID-19 disease: insights from a multicenter international cohort study.

BACKGROUND: Lung perfusion defects, mainly due to endothelial and coagulation activation, are a key contributor to COVID-19 respiratory failure. COVID-19 patients may also develop acute kidney injury (AKI) because of renal perfusion deficit. We aimed to explore AKI-associated factors and the independent prediction of standardized minute ventilation (MV)-a proxy of alveolar dead space-on AKI onset and persistence in COVID-19 mechanically ventilated patients. METHODS: This is a multicenter observational cohort study. We enrolled 157 COVID-19 patients requiring mechanical ventilation and intensive care unit (ICU) admission. We collected clinical information, ventilation, and laboratory data. AKI was defined by the 2012 KDIGO guidelines and classified as transient or persistent according to serum creatinine criteria persistence within 48 h. Ordered univariate and multivariate logistic regression analyses were employed to identify variables associated with AKI onset and persistence. RESULTS: Among 157 COVID-19 patients on mechanical ventilation, 47% developed AKI: 10% had transient AKI, and 37% had persistent AKI. The degree of hypoxia was not associated with differences in AKI severity. Across increasing severity of AKI groups, despite similar levels of paCO2, we observed an increased MV and standardized MV, a robust proxy of alveolar dead space. After adjusting for other clinical and laboratory covariates, standardized MV remained an independent predictor of AKI development and persistence. D-dimer levels were higher in patients with persistent AKI. CONCLUSIONS: In critically ill COVID-19 patients with respiratory failure, increased wasted ventilation is independently associated with a greater risk of persistent AKI. These hypothesis-generating findings may suggest that perfusion derangements may link the pathophysiology of both wasted ventilation and acute kidney injury in our population.

The impact of diabetes mellitus on foot perfusion measured by ICG NIR fluorescence imaging.

INTRODUCTION: Diabetes Mellitus (DM) is a common chronic disease, affecting 435 million people globally. Impaired vasculature in DM patients leads to complications like lower extremity arterial disease (LEAD) and foot ulcers, often resulting in amputations. DM causes additional peripheral neuropathy leading to multifactorial wound problems. Current diagnostics often deem unreliable, but Near-Infrared Fluorescence with Indocyanine Green (ICG NIR) can be used to assess the foot perfusion. Therefore, this study explores DM's impact on foot perfusion using ICG NIR. METHODS: Baseline ICG NIR fluorescence imaging was performed in LEAD patients with and without DM. Ten perfusion parameters were extracted and analyzed to assess differences in perfusion patterns. RESULTS: Among 109 patients (122 limbs) of the included patients, 32.8% had DM. Six of ten perfusion parameters, mainly inflow-related, differed significantly between DM and non-DM patients (p-values 0.007-0.039). Fontaine stage 4 DM patients had the highest in- and outflow values, with seven parameters significantly higher (p-values 0.004-0.035). CONCLUSION: DM is associated with increased in- and outflow parameters. Patients with- and without DM should not be compared directly due to different vascular pathophysiology and multifactorial wound problems in DM patients. Quantified ICG NIR fluorescence imaging offers additional insight into the effect of DM on foot perfusion.

Physical enhancement of older adults using hyperbaric oxygen: a randomized controlled trial.

INTRODUCTION: Aging is associated with a progressive decline in the capacity for physical activity. The objective of the current study was to evaluate the effect of an intermittent hyperbaric oxygen therapy (HBOT) protocol on maximal physical performance and cardiac perfusion in sedentary older adults. METHODS: A randomized controlled clinical trial randomized 63 adults (> 64yrs) either to HBOT (n = 30) or control arms (n = 33) for three months. Primary endpoint included the maximal oxygen consumption (VO2Max) and VO2Max/Kg, on an E100 cycle ergometer. Secondary endpoints included cardiac perfusion, evaluated by magnetic resonance imaging and pulmonary function. The HBOT protocol comprised of 60 sessions administered on a daily basis, for 12 consecutive weeks, breathing 100% oxygen at 2 absolute atmospheres (ATA) for 90 min with 5-minute air breaks every 20 min. RESULTS: Following HBOT, improvements were observed in VO2Max/kg, with a significant increase of 1.91 ± 3.29 ml/kg/min indicated by a net effect size of 0.455 (p = 0.0034). Additionally, oxygen consumption measured at the first ventilatory threshold (VO2VT1) showed a significant increase by 160.03 ± 155.35 ml/min (p < 0.001) with a net effect size of 0.617. Furthermore, both cardiac blood flow (MBF) and cardiac blood volume (MBV) exhibited significant increases when compared to the control group. The net effect size for MBF was large at 0.797 (p = 0.008), while the net effect size for MBV was even larger at 0.896 (p = 0.009). CONCLUSION: The findings of the study indicate that HBOT has the potential to improve physical performance in aging adults. The enhancements observed encompass improvements in key factors including VO2Max, and VO2VT1. An important mechanism contributing to these improvements is the heightened cardiac perfusion induced by HBOT. TRIAL REGISTRATION: ClinicalTrials.gov Identifier NCT02790541 (registration date 06/06/2016).

Assessment of pharmacologically induced changes in canine kidney function by multiparametric magnetic resonance imaging and contrast enhanced ultrasound.

Introduction: Dynamic contrast-enhanced (DCE) MRI and arterial spin labeling (ASL) MRI enable non-invasive measurement of renal blood flow (RBF), whereas blood oxygenation level-dependent (BOLD) MRI enables non-invasive measurement of the apparent relaxation rate (R2*), an indicator of oxygenation. This study was conducted to evaluate the potential role of these MRI modalities in assessing RBF and oxygenation in dogs. The correlation between contrast-enhanced ultrasound (CEUS) and the MRI modalities was examined and also the ability of the MRI modalities to detect pharmacologically induced changes. Methods: RBF, using CEUS, ASL- and DCE-MRI, as well as renal oxygenation, using BOLD-MRI of eight adult beagles were assessed at two time-points, 2­3 weeks apart. During each time point, the anesthetized dogs received either a control (0.9% sodium chloride) or a dopamine treatment. For each time point, measurements were carried out over 2 days. An MRI scan at 3 T was performed on day one, followed by CEUS on day two. Results: Using the model-free model with caudal placement of the arterial input function (AIF) region of interest (ROI) in the aorta, the DCE results showed a significant correlation with ASL measured RBF and detected significant changes in blood flow during dopamine infusion. Additionally, R2* negatively correlated with ASL measured RBF at the cortex and medulla, as well as with medullary wash-in rate (WiR) and peak intensity (PI). ASL measured RBF, in its turn, showed a positive correlation with cortical WiR, PI, area under the curve (AUC) and fall time (FT), and with medullary WiR and PI, but a negative correlation with medullary rise time (RT). During dopamine infusion, BOLD-MRI observed a significant decrease in R2* at the medulla and entire kidney, while ASL-MRI demonstrated a significant increase in RBF at the cortex, medulla and the entire kidney. Conclusion: ASL- and BOLD-MRI can measure pharmacologically induced changes in renal blood flow and renal oxygenation in dogs and might allow detection of changes that cannot be observed with CEUS. However, further research is needed to confirm the potential of ASL- and BOLD-MRI in dogs and to clarify which analysis method is most suitable for DCE-MRI in dogs.

Multimodality assessment of the coronary microvasculature with TIMI frame count versus perfusion PET highlights coronary changes characteristic of coronary microvascular disease.

Background: The diagnosis of coronary microvascular disease (CMVD) remains challenging. Perfusion PET-derived myocardial blood flow (MBF) reserve (MBFR) can quantify CMVD but is not widely available. Thrombolysis in Myocardial Infarction (TIMI) frame count (TFC) is an angiography-based method that has been proposed as a measure of CMVD. Here, we compare TFC and PET-derived MBF measurements to establish the role of TFC in assessing for CMVD. We use coronary modeling to elucidate the relationship between MBFR and TFC and propose TFC thresholds for identifying CMVD. Methods: In a cohort of 123 individuals (age 58 ± 12.1, 63% women, 41% Caucasian) without obstructive coronary artery disease who had undergone perfusion PET and coronary angiography for clinical indications, we compared TFC and perfusion PET parameters using Pearson correlation (PCC) and linear regression modeling. We used mathematical modeling of the coronary circulation to understand the relationship between these parameters and performed Receiver Operating Curve (ROC) analysis. Results: We found a significant negative correlation between TFC and MBFR. Sex, race and ethnicity, and nitroglycerin administration impact this relationship. Coronary modeling showed an uncoupling between TFC and flow in epicardial vessels. In ROC analysis, TFC performed well in women (AUC 0.84-0.89) and a moderately in men (AUC 0.68-0.78). Conclusions: We established an inverse relationship between TFC and PET-derived MBFR, which is affected by patient selection and procedural factors. TFC represents a measure of the volume of the epicardial coronary compartment, which is increased in patients with CMVD, and performs well in identifying women with CMVD.

Neurological outcomes for patients meeting radiographic criteria for DEFUSE 3 and SELECT2.

BACKGROUND: The DEFUSE 3 and SELECT2 thrombectomy trials included some patients with similar radiographic profiles, although the rates of good functional outcomes differed widely between the studies. OBJECTIVE: To report neurological outcomes for patients who meet CT and CT perfusion (CTP) inclusion criteria common to both DEFUSE 3 and SELECT2. METHODS: Retrospective study of thrombectomy patients, presenting between November 2016 and December 2023 to a large health system, with Alberta Stroke Program Early CT score ≥6, core infarction 50-69 mL, mismatch ratio ≥1.8, and mismatch volume ≥15 mL. The primary outcome was 90-day modified Rankin Scale score 0-2. A logistic regression analysis was performed to identify independent predictors of the primary outcome. RESULTS: 85 patients, with mean age 64.6 (16.6) years and median National Institutes of Health Stroke Scale score 18 (15-23), were included. Thirty-eight of 85 patients (44.7%) were functionally independent at 90 days. Predictors of functional independence included age (OR=0.943, 95% CI 0.908 to 0.980; P=0.003), initial glucose (OR=0.989, 95% CI 0.978 to 1.000; P=0.044), and time last known well to skin puncture (OR=0.997, 95% CI 0.994 to 1.000; P=0.028). The area under the curve for the multivariable model predicting the primary outcome was 0.82 (95% CI 0.73 to 0.92). CONCLUSION: Nearly half of patients meeting radiographic criteria common to DEFUSE 3 and SELECT2 are functionally independent at 90 days, similar to rates reported for the treated DEFUSE 3 cohort. This might be due to their moderate core volumes and large ischemic penumbra.

Tissue perfusion in DIEP flaps using Indocyanine Green Fluorescence Angiography, Hyperspectral imaging, and Thermal imaging.

Flap necrosis continues to occur in skin free flap autologous breast reconstruction. Therefore, we investigated the benefits of indocyanine green angiography (ICGA) using quantitative parameters for the objective, perioperative evaluation of flap perfusion. In addition, we investigated the feasibility of hyperspectral (HSI) and thermal imaging (TI) for postoperative flap monitoring. A single-center, prospective observational study was performed on 15 patients who underwent deep inferior epigastric perforator (DIEP) flap breast reconstruction (n=21). DIEP-flap perfusion was evaluated using ICGA, HSI, and TI using a standardized imaging protocol. The ICGA perfusion curves and derived parameters, HSI extracted oxyhemoglobin (oxyHb) and deoxyhemoglobin (deoxyHb) values, and flap temperatures from TI were analyzed and correlated to the clinical outcomes. Post-hoc quantitative analysis of intraoperatively collected data of ICGA application accurately distinguished between adequately and insufficiently perfused DIEP flaps. ICG perfusion curves identified the lack of arterial inflow (n=2) and occlusion of the venous outflow (n=1). In addition, a postoperatively detected partial flap epidermolysis could have been predicted based on intraoperative quantitative ICGA data. During postoperative monitoring, HSI was used to identify impaired perfusion areas within the DIEP flap based on deoxyHb levels. The results of this study showed a limited added value of TI. Quantitative, post-hoc analysis of ICGA data produced objective and reproducible parameters that enabled the intraoperative detection of arterial and venous congested DIEP flaps. HSI appeared to be a promising technique for postoperative flap perfusion assessment. A diagnostic accuracy study is needed to investigate ICGA and HSI parameters in real-time and demonstrate their clinical benefit.

[Effect of Intrauterine Perfusion of Granulocyte Colony-Stimulating Factor on Endometrium and Blood Flow Parameters in Patients With Thin Endometrium: A Prospective Controlled Clinical Trial]. / å®«è ”çŒæ³¨ç²’ç»†èƒžé›†è½åˆºæ¿€å› å­æ”¹å–„è–„åž‹å­å®«å† è†œæ‚£è€ å† è†œåŠè¡€æµå‚æ•°çš„å‰çž»æ€§ä¸´åºŠå¯¹ç §è¯•éªŒ.

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

Cold ischemia time in liver transplantation: An overview.

The standard approach to organ preservation in liver transplantation is by static cold storage and the time between the cross-clamping of a graft in a donor and its reperfusion in the recipient is defined as cold ischemia time (CIT). This simple definition reveals a multifactorial time frame that depends on donor hepatectomy time, transit time, and recipient surgery time, and is one of the most important donor-related risk factors which may influence the graft and recipient's survival. Recently, the growing demand for the use of marginal liver grafts has prompted scientific exploration to analyze ischemia time factors and develop different organ preservation strategies. This review details the CIT definition and analyzes its different factors. It also explores the most recent strategies developed to implement each timestamp of CIT and to protect the graft from ischemic injury.

Non-contrast free-breathing liver perfusion imaging using velocity selective ASL combined with prospective motion compensation.

PURPOSE: To apply velocity selective arterial spin labeling (VSASL) combined with a navigator-based (NAV) prospective motion compensation method for a free-breathing liver perfusion measurement without contrast agent. METHODS: Sinc-modulated Velocity Selective Inversion (sinc-VSI) pulses were applied as labeling and control pulses. In order to account for respiratory motion, a navigator was employed in the form of a single gradient-echo projection readout, located at the diaphragm along the inferior-superior direction. Prior to each transverse imaging slice of the spin-echo EPI based readouts, navigator and fat suppression were incorporated. Motion data was obtained from the navigator and transmitted back to the sequence, allowing real-time adjustments to slice positioning. The sinc-VSI without velocity-selective gradients during the control condition but with velocity-selective gradients along all three directions during labeling was chosen for the VSASL. The VSASL was compared with pseudo-continuous ASL (pCASL) methods, which selectively tagged the moving spins using a tagging plane placed at the portal vein and hepatic artery. RESULTS: The motion caused by respiratory activity was effectively computed using the navigator signal. The coefficients of variation (CoV) of average liver voxel in NAV were significantly decreased when compared to breath-hold (BH), with an average reduction of 29.4 ±â€¯18.44% for control images, and 29.89 ±â€¯20.83% for label images (p < 0.001). The resulting maps of normalized ASL signal (normalized to M0) showed significantly higher perfusion weightings in the NAV-compensated VSASL, when compared to the NAV-compensated pCASL techniques. CONCLUSIONS: This study demonstrates the feasibility of using a navigator-based prospective motion compensation technique in conjunction with VSASL for the measurement of liver perfusion without the use of contrast agents while allowing for free-breathing.

Assessing the diagnostic value of left ventricular synchrony indices derived from phase analysis by D-SPECT in identifying obstructive coronary artery disease.

This study aimed to assess the diagnostic efficacy of left ventricular synchrony (LVS) for detecting coronary artery disease (CAD). We explored whether the LVS index derived from phase analysis of D-SPECT provides superior diagnostic value compared to conventional perfusion analysis in identifying obstructive CAD. Patients with suspected or confirmed CAD underwent drug-stress/rest gated D-SPECT myocardial perfusion imaging (MPI) and coronary angiography (CAG). A 50% stenosis was set as the threshold for obstructive CAD. 110 participants were enrolled in this analysis. There were significant differences in phase standard deviation (PSD), phase histogram bandwidth (PHB) and entropy among the four groups. Patients without cardiac disease and those with mild-moderate stenosis exhibited no noticeable contraction asynchrony. However, LVS indices demonstrated a gradual increase with the progression of coronary stenosis when compared to NC (P < 0.001). Obstructive CAD was identified in 43 out of 110 participants (39%). Optimal cutoff values for diagnosing obstructive CAD during stress were determined as 7.6° for PSD, 24° for PHB, and 37% for entropy, respectively. Notably, PSD, PHB, and entropy indices exhibited higher sensitivity compared to MPI. The integration of the stress-induced LVS indices into routine MPI analysis resulted in a significantly greater area under the curve (AUC), leading to improved diagnostic performance and enhanced differential capacity. Stress-induced LVS indices increase with the severity of coronary artery stenosis by D-SPECT phase analysis. Further, the indices-derived phase analysis exhibits superior sensitivity and discriminatory ability compared to MPI in detecting obstructive CAD.

[Terminology of quantitative optical coherence tomography angiography metrics]. / Osobennosti terminologii kolichestvennykh pokazatelei opticheskoi kogerentnoi tomografii-angiografii.

This review is devoted to the English- and Russian-language terminology of quantitative metrics that are used in the evaluation of images obtained by optical coherence tomography angiography (OCT-A). The paper presents an analysis of the use of terms characterizing intraretinal blood flow (vascular density, perfusion density, skeletonized density, etc.), area and shape of the foveal avascular zone, and choriocapillaris blood flow. The factors causing the heterogeneity of OCT-A terminology are described, including the lack of a unified international nomenclature for OCT-A, features of their Russian translation, inconsistency of the parameters in optical coherence tomography systems of different manufacturers. The article also considers ways to standardize the terminology.

Double arterial vs. single axillary cannulation in acute type A aortic dissections: a meta-analysis.

Aim: To evaluate the effects of double (axillary and femoral) vs. single (axillary) cannulation on early outcomes of acute type A aortic dissection (ATAAD). Materials & methods: Meta-analysis using PubMed/MEDLINE, Scopus, and Cochrane databases through August 23, 2023. Focused on operative mortality, postoperative stroke, re-exploration for bleeding, spinal cord injury, and renal replacement therapy. Results: Among 5 propensity score-matched studies with 2127 patients, double cannulation showed comparable mortality and higher rates of postoperative stroke (pooled odds ratio: 1.69, 95% confidence interval: 1.19-2.39) and need for renal replacement therapy (pooled odds ratio: 1.35, 95% confidence interval: 1.13-1.60) compared with single cannulation. Conclusion: Double arterial cannulation in ATAAD surgery is associated with increased postoperative stroke and renal replacement therapy than single cannulation.

What is this summary about? We studied the optimal way to maintain blood flow during surgery for acute aortic dissection. We focused on comparing the use of one tube placement site in the axillary artery with two sites, both in the axillary and femoral arteries, in five previous studies.What were the results? Using two sites was associated with a higher risk of stroke and need for dialysis after surgery than using only one site.What do the results mean? Adding a tube in the femoral artery for blood flow may increase the risk of complications. It appears that placing the tube only in the axillary artery may be a safer choice for appropriately selected patients having this surgery.

Ex-Vivo Kidney Perfusion With Hemoglobin-Based Oxygen Carriers, Red Blood Cells, or No Oxygen Carrier.

INTRODUCTION: Normothermic machine perfusion (NMP) of donor kidneys provides the opportunity to assess and improve organ viability prior to transplantation. This study explored the necessity of an oxygen carrier during NMP and whether the hemoglobin-based oxygen carrier (HBOC-201) is a suitable alternative to red blood cells (RBCs). METHODS: Porcine kidneys were perfused with a perfusion solution containing either no-oxygen carrier, RBCs, or HBOC-201 for 360 min at 37°C. RESULTS: Renal flow and resistance did not differ significantly between groups. NMP without an oxygen carrier showed lower oxygen consumption with higher lactate and aspartate aminotransferase levels, indicating that the use of an oxygen carrier is necessary for NMP. Cumulative urine production and creatinine clearance in the RBC group were significantly higher than in the HBOC-201 group. Oxygen consumption, injury markers, and histology did not differ significantly between these two groups. However, methemoglobin levels increased to 45% after 360 min in the HBOC-201 group. CONCLUSIONS: We conclude that HBOC-201 could be used as an alternative for RBCs, but accumulating methemoglobin levels during our perfusions indicated that HBOC-201 is probably less suitable for prolonged NMP. Perfusion with RBCs, compared to HBOC-201, resulted in more favorable renal function during NMP.