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Cultivations of Chinese Hamster Ovary (CHO) cells in a perfusion setup were conducted in the presence of super physiological concentrations of L-Arginine to investigate the impact on transmission through the perfusion filter for production of a recombinant domain antibody. Our study revealed that the presence of L-Arginine within the range of 30–50 mM had a positive impact on transmission. However, the higher concentrations were found to have a negative correlation with cell viability, and an optimal concentration of approximately 40 mM was identified. The supplementation of L-Arginine improved overall cultivation performance and enhanced product quality attributes. As a result, our findings demonstrate that the supplementation of L-Arginine to mammalian perfusion cultivations stands as an effective method to address transmission issues, exerting a broad impact on process and production of recombinant proteins. • Mammalian cell cultivations with high L-Arginine assessed impact on transmission for domain antibody production. • 30–50 mM L-Arginine positively affected transmission, while excessive concentrations impacted viability. • Optimal 40 mM improved transmission, positively influencing performance and product quality. • L-Arginine in perfusion cultivations offers a method for resolving transmission issues. • Findings suggest general applicability of L-Arginine in improving recombinant protein production. [ABSTRACT FROM AUTHOR]

Background Purpose Methods Results Conclusion Total‐body positron emission tomography (PET), already well‐established in the pre‐clinical setting, makes it possible to study multi‐parameters in biological systems as a whole, rather than focusing on single tissues analysis. Simultaneous kinetic analysis of multiple organs poses some daunting new challenges.To explore quantifying the pharmacokinetics of Na[18F]F in multiple dissimilar murine organs simultaneously in vivo with total‐body PET imaging using different compartmental models for each organ and a shared cardiovascular system.Six mice underwent a 60‐min total‐body PET scan following intravenous bolus injection of Na[18F]F. Compartmental models were constructed for each organ (heart, lungs, liver, kidneys, and bone) using an image derived input function. Non‐linear least squares fitting of a model that connects the five organs to a shared cardiovascular system was used to analyze both the first 3 min of data and the full hour. Analysis was repeated 5000 times using different initial parameter values for each duration, permitting analysis of correlations between parameters.The models give a good qualitative account of the activity curves irrespective of the duration of the data; however, the quality of the fits to 3 min of data (average χν2$\chi _\nu ^2$ is 2.72) was generally better. Comparison of perfusion values to literature values was possible for the liver and lungs with the former (liver, 0.540 ± 0.177 mL/ml/min) being well‐above expectations and the latter (lungs, 0.184 ± 0.413 mL/ml/min) in rough agreement. Correlations between microparameter values (especially affecting k2) caused very noticeable problems for data modeling from both the kidneys and the femur.The present study demonstrates an approach to performing kinetic modeling for multiple organs simultaneously with Na[18F]F. The observed correlations between microparameter values remain a challenge. Nonetheless, many microparameters can be estimated reliably with a quantitative analysis of perfusion being possible for some organs. [ABSTRACT FROM AUTHOR]

Purpose: Tumour perfusion is a nutrient-agnostic biomarker for cancer metabolic rate. Use of tumour perfusion for cancer growth assessment has been limited by complicated image acquisition, image analysis and limited field-of-view scanners. Long axial field-of-view (LAFOV) PET scan using [15O]H2O, allows quantitative assessment of whole-body tumour perfusion. We created a tool for automated creation of quantitative parametric whole-body tumour perfusion images in metastatic cancer. Methods: Ten metastatic prostate cancer patients underwent dynamic LAFOV [15O]H2O PET (Siemens, Quadra) followed by [18F]PSMA-1007 PET. Perfusion was measured as [15O]H2O K1 (mL/min/mL) with a single-tissue compartment model and an automatically captured cardiac image-derived input function. Parametric perfusion images were automatically calculated using the basis-function method with initial voxel-wise delay estimation and a leading-edge approach. Subsequently, perfusion of volumes-of-interest (VOI) can be directly extracted from the parametric images. We used a [18F]PSMA-1007 SUV 4 fixed threshold for tumour delineation and transferred these VOIs to the perfusion map. Results: For 8 primary tumours, 64 lymph node metastases, and 85 bone metastases, median tumour perfusion were 0.19 (0.15–0.27) mL/min/mL, 0.16 (0.13–0.27) mL/min/mL, and 0.26 (0.21–0.39), respectively. The correlation between calculated perfusion from time-activity-curves and parametric images was excellent (r = 0.99, p < 0.0001). Conclusion: LAFOV PET imaging using [15O]H2O enables truly quantitative parametric images of whole-body tumour perfusion, a potential biomarker for guiding personalized treatment and monitoring treatment response. [ABSTRACT FROM AUTHOR]

Background: This study examines the role of extracorporeal life support flow in the development of acute kidney injury in cardiogenic shock. Methods: We performed a retrospective analysis of 465 patients placed on extracorporeal life support at our institution between January 2015 and December 2020 for cardiogenic shock. Flow index was calculated by dividing mean flow by body surface. Stages of acute kidney injury were determined according to Kidney Disease: Improving Global Outcomes (KDIGO) organization guidelines. Results: There were 179 (38.5%) patients who developed acute kidney injury, 63.1% of which were classified as Stage 3--the only subgroup associated with 1-year mortality (hazard ratio = 2.03, p <.001). Risk of k idney injury increased up to a flow index of 1.6 L/min/m2, and kidney injury was more common among patients with flow index greater than 1.6 L/min/m2 (p =.034). Those with kidney injury had higher baseline lactate levels (4.4 vs 3.1, p =.04), and Stage 3 was associated wit higher baseline creatinine (p <.001). Conclusions: In our cohort, kidney injury was common and Stage 3 kidney injury was associated with worse outcomes compared to other stages. Low flow was not associated with increased risk of kidney injury. Elevated baseline lactate and creatinine among patients with acute kidney injury suggest underlying illness severity, rather than flow, may influence kidney injury risk. [ABSTRACT FROM AUTHOR]

Antegrade cardioplegia is routinely given during cardiac surgery. The delivery of antegrade cardioplegia from the cardiopulmonary bypass machine has many variables. Many perfusionists rely exclusively on cardioplegia system pressure to ensure safe antegrade delivery. Our group reviewed antegrade cardioplegia delivery in 50 patients undergoing coronary artery bypass graft. The data collected included the cardioplegia system pressure and the patient's direct aortic root pressure. The analysis of the data found weak correlation between the two pressures with a large mean difference and a wide standard deviation. The results suggest the direct measurement of aortic root pressure as guidance to antegrade cardioplegia instead of relying solely on cardioplegia system pressure. [ABSTRACT FROM AUTHOR]

Background: Cerebral perfusion pressure (CPP) is an important target in aneurysmal subarachnoid hemorrhage (aSAH), but it does not take into account autoregulatory disturbances. The pressure reactivity index (PRx) and the CPP with the optimal PRx (CPPopt) are new variables that may capture these pathomechanisms. In this study, we investigated the effect on the outcome of certain combinations of CPP or ΔCPPopt (actual CPP-CPPopt) with the concurrent autoregulatory status (PRx) after aSAH. Methods: This observational study included 432 aSAH patients, treated in the neurointensive care unit, at Uppsala University Hospital, Sweden. Functional outcome (GOS-E) was assessed 1-year postictus. Heatmaps of the percentage of good monitoring time (%GMT) of PRx/CPP and PRx/ΔCPPopt combinations in relation to GOS-E were created to visualize the association between these variables and outcome. Results: In the heatmap of the %GMT of PRx/CPP, the combination of lower CPP with higher PRx values was more strongly associated with lower GOS-E. The tolerance for lower CPP values increased with lower PRx values until a threshold of −0.50. However, for decreasing PRx below −0.50, there was a gradual reduction in the tolerance for lower CPP. In the heatmap of the %GMT of PRx/ΔCPPopt, the combination of negative ΔCPPopt with higher PRx values was strongly associated with lower GOS-E. In particular, negative ΔCPPopt together with PRx above +0.50 correlated with worse outcomes. In addition, there was a transition toward an unfavorable outcome when PRx went below −0.50, particularly if ΔCPPopt was negative. Conclusions: The PRx levels influenced the association between CPP/ΔCPPopt and outcome. Thus, this variable could be used to individualize a safe CPP-/ΔCPPopt-range. [ABSTRACT FROM AUTHOR]

Background: Liver transplantation is used for treating end‐stage liver disease, fulminant hepatitis, and oncological malignancies and organ shortage is a major limiting factor worldwide. The use of grafts based on extended donor criteria have become internationally accepted. Oxygenated machine perfusion technologies are the most recent advances in organ transplantation; however, it is only applied after a period of cold ischemia. Due to its high cost, we aimed to use a novel device, OxyFlush®, based on oxygenation of the preservation solution, applied during liver procurement targeting the maintenance of ATP during static cold storage (SCS). Methods: Twenty patients were randomly assigned to the OxyFlush or control group based on a 1:1 ratio. In the OxyFlush group, the perfusion solution was oxygenated with OxyFlush® device while the control group received a non‐oxygenated solution. Liver and the common bile duct (CBD) biopsies were obtained at three different time points. The first was at the beginning of the procedure, the second during organ preparation, and the third after total liver reperfusion. Biopsies were analyzed, and adenosine triphosphate (ATP) levels and histological scores of the liver parenchyma and CBD were assessed. Postoperative laboratory tests were performed. Results: OxyFlush® was able to maintain ATP levels during SCS and improved the damage caused by the lack of oxygen in the CBD. However, OxyFlush® did not affect laboratory test results and histological findings of the parenchyma. Conclusion: We present a novel low‐cost device that is feasible and could represent a valuable tool in organ preservation during SCS. [ABSTRACT FROM AUTHOR]

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The purpose of this study was to evaluate the effects of contrast heat and cold pressure therapy (CHCP) on muscle tone, elasticity, stiffness, perfusion unit, and muscle fatigue indices after plyometric training consisting of five sets of jumping on a 50-cm high box until exhaustion. A prospective, randomized, controlled single-blind study design was used. Twenty professional MMA fighters were included in the study. The experimental group (n = 10) was subjected to the CHCP protocol (eGR), while the control group (cGR) (n = 10) was subjected to sham therapy. Both protocols consisted of three CHCP sessions performed immediately after plyometric exercise, 24 and 48 h afterwards. Measurements were taken at the following time points: 1) at rest; 2) 1 min post-exercise; 3) 1 min post-CHCP therapy; 4) 24 h post-CHCP therapy; 5) 48 h post-CHCP therapy. The results of the eGR compared to the cGR showed significantly higher perfusion at time point 5 (p < 0.001), higher muscle tone at time points 1, and 3-5 (p < 0.001 for all), higher stiffness at time points 1, 3-5 (p < 0.001 for all) and a higher pain threshold at time points 1 and 5 (p < 0.001 for all). This study suggests a positive effect of CHCP therapy on muscle biomechanics, the pain threshold, and tissue perfusion, which may contribute to increasing the effectiveness of post-exercise muscle recovery in MMA athletes. [ABSTRACT FROM AUTHOR]

Purpose: For reliable DCE MRI parameter estimation, k‐space undersampling is essential to meet resolution, coverage, and signal‐to‐noise requirements. Pseudo‐spiral (PS) sampling achieves this by sampling k‐space on a Cartesian grid following a spiral trajectory. The goal was to optimize PS k‐space sampling patterns for abdomin al DCE MRI. Methods: The optimal PS k‐space sampling pattern was determined using an anthropomorphic digital phantom. Contrast agent inflow was simulated in the liver, spleen, pancreas, and pancreatic ductal adenocarcinoma (PDAC). A total of 704 variable sampling and reconstruction approaches were created using three algorithms using different parametrizations to control sampling density, halfscan and compressed sensing regularization. The sampling patterns were evaluated based on image quality scores and the accuracy and precision of the DCE pharmacokinetic parameters. The best and worst strategies were assessed in vivo in five healthy volunteers without contrast agent administration. The best strategy was tested in a DCE scan of a PDAC patient. Results: The best PS reconstruction was found to be PS‐diffuse based, with quadratic distribution of readouts on a spiral, without random shuffling, halfscan factor of 0.8, and total variation regularization of 0.05 in the spatial and temporal domains. The best scoring strategy showed sharper images with less prominent artifacts in healthy volunteers compared to the worst strategy. Our suggested DCE sampling strategy also showed high quality DCE images in the PDAC patient. Conclusion: Using an anthropomorphic digital phantom, we identified an optimal PS sampling strategy for abdominal DCE MRI, and demonstrated feasibility in a PDAC patient. [ABSTRACT FROM AUTHOR]

Background: Sitting is known to be bad for your cardiovascular health. We furthermore hypothesized that sitting posture will reduce perfusion of the foot and increase edema, possibly predisposing to disease like osteochondritis. Methods: We included 27 healthy volunteers and performed MRI measurements including arterial spin labelling (ASL) and intravoxel incoherent motion (IVIM) perfusion as well as short tau inversion recovery (STIR) edema measurement and 3D volumetry. After randomization, the elevation of one foot during the day was used as an intervention. Results: Intra- and interrater variability was 1–6%. ASL perfusion measurement was hindered by artifacts. IVIM perfusion showed no significant changes during supine measurements. Volumetry could demonstrate a highly significant (p = 0.00005) volume increase, while the intervention led to a significant (p = 0.0076) volume decrease during the day. However, the water content in STIR remained unchanged and the normalized (quotient bone/muscle) edema was reduced on the control side (p = 0.006) and increased on the intervention side (p = 0.01). Conclusions: Sitting all day leads to swelling of the healthy foot. Compensation in healthy subjects seems to prevent lasting perfusion changes or edema evolution in the bone despite an increase of muscle signal and volume increase. Thus, the etiology of osteochondritis needs further studies. [ABSTRACT FROM AUTHOR]

Background: Pulmonary embolism (PE) is life-threatening and requires timely and accurate diagnosis, yet current imaging methods, like computed tomography pulmonary angiography, present limitations, particularly for patients with contraindications to iodinated contrast agents. We aimed to develop a quantitative texture analysis pipeline using machine learning (ML) based on non-contrast thoracic computed tomography (CT) scans to discover intensity and textural features correlated with regional lung perfusion (Q) physiology and pathology and synthesize voxel-wise Q surrogates to assist in PE diagnosis. Methods: We retrospectively collected 99mTc-labeled macroaggregated albumin Q-SPECT/CT scans from patients suspected of PE, including an internal dataset of 76 patients (64 for training, 12 for testing) and an external testing dataset of 49 patients. Quantitative CT features were extracted from segmented lung subregions and underwent a two-stage feature selection pipeline. The prior-knowledge-driven preselection stage screened for robust and non-redundant perfusion-correlated features, while the data-driven selection stage further filtered features by fitting ML models for classification. The final classification model, trained with the highest-performing PE-associated feature combination, was evaluated in the testing cohorts based on the Area Under the Curve (AUC) for subregion-level predictability. The voxel-wise Q surrogate was then synthesized using the final selected feature maps (FMs) and model score maps (MSMs) to investigate spatial distributions. The Spearman correlation coefficient (SCC) and Dice similarity coefficient (DSC) were used to assess the spatial consistency between FMs or MSMs and Q-SPECT scans. Results: The optimal model performance achieved an AUC of 0.863 during internal testing and 0.828 on the external testing cohort. The model identified a combination containing 14 intensity and textural features that were non-redundant, robust, and capable of distinguishing between high- and low-functional lung regions. Spatial consistency assessment in the internal testing cohort showed moderate-to-high agreement between MSMs and reference Q-SPECT scans, with median SCC of 0.66, median DSCs of 0.86 and 0.64 for high- and low-functional regions, respectively. Conclusions: This study validated the feasibility of using quantitative texture analysis and a data-driven ML pipeline to generate voxel-wise lung perfusion surrogates, providing a radiation-free, widely accessible alternative to functional lung imaging in managing pulmonary vascular diseases. Clinical trial number: Not applicable. [ABSTRACT FROM AUTHOR]

Dynamic contrast-enhanced MRI (DCE-MRI) is increasingly used to non-invasively image blood-brain barrier leakage, yet its clinical utility has been hampered by issues such as noise and partial volume artifacts. In this retrospective study involving 306 adult patients with diffuse glioma, we applied deep learning-based super-resolution and denoising (DLSD) techniques to enhance the signal-to-noise ratio (SNR) and resolution of DCE-MRI. Quantitative analysis comparing standard DCE-MRI (std-DCE) and DL-enhanced DCE-MRI (DL-DCE) revealed that DL-DCE achieved significantly higher SNR and contrast-to-noise ratio (CNR) compared to std-DCE (SNR, 52.09 vs 27.21; CNR, 9.40 vs 4.71; P < 0.001 for all). Diagnostic performance assessed by the area under the receiver operating characteristic curve (AUROC) showed improved differentiation of WHO grades based on a pharmacokinetic parameter (AUC, 0.88 vs 0.83, P = 0.02), while remaining comparable to std-DCE in other parameters. Analysis of arterial input function (AIF) reliability demonstrated that exhibited superior agreement compared to , as indicated by mostly higher intraclass correlation coefficients (Time to peak, 0.79 vs 0.43, P < 0.001). In conclusion, DLSD significantly enhances both the image quality and reliability of DCE-MRI in patients with diffuse glioma, while maintaining or improving diagnostic performance. [ABSTRACT FROM AUTHOR]

Introduction: In multiplexed positron emission tomography (mPET) imaging, physiological and pathological information from different radiotracers can be observed simultaneously in a single dynamic PET scan. The separation of mPET signals within a single PET scan is challenging due to the fact that the PET scanner measures the sum of the PET signals of all the tracers. The conventional multitracer compartment modeling (MTCM) method requires staggered injections and assumes that the arterial input functions (AIFs) of each tracer are known. Methods: In this work, we propose a deep learning-based method to separate triple-tracer PET images without explicitly knowing the AIFs. A dynamic tripletracer noisy MLEM reconstruction was used as the network input, and dynamic single-tracer noisy MLEM reconstructions were used as training labels. Results: A simulation study was performed to evaluate the performance of the proposed framework on triple-tracer ([18F]FDG+82Rb+[94mTc]sestamibi) PET myocardial imaging. The results show that the proposed methodology substantially reduced the noise level compared to the results obtained from single-tracer imaging. Additionally, it achieved lower bias and standard deviation in the separated single-tracer images compared to the MTCM-based method at both the voxel and region of interest (ROI) levels. Discussion: As compared to MTCM separation, the proposed method uses spatiotemporal information for separation, which improves the separation performance at both the voxel and ROI levels. The simulation study also demonstrates the feasibility and potential of the proposed DL-based method for the application to pre-clinical and clinical studies. [ABSTRACT FROM AUTHOR]

Emergency computed tomography (CT) often does not allow for comprehensive coronary artery assessment. However, CT may reveal pathological myocardial hypoperfusion suggestive of acute myocardial infarction (AMI), especially in patients presenting with a different diagnostic hypothesis. CT hypoperfusion is known to be associated with myocardial infarction, however the diagnostic value of CT hypoperfusion for the detection of AMI is still not well evaluated. This was a single-centre retrospective study including patients who underwent invasive coronary angiography (ICA) due to suspected AMI based on incidental perfusion defects upon emergency CT imaging between 2018 and 2023. A total of 22 patients (mean age 66.3 ± 10.8 years, 11 female) were included in this analysis. The diagnosis of AMI was established in all cases leading to ICA. Culprit coronary artery lesions with an indication of percutaneous coronary intervention were detected in all patients who underwent ICA. Spearmann correlation for hypoperfused segments on CT imaging and the corresponding vascular territory upon ICA was significantly substantial (ρ = 0.73, p = < 0.001). The higher the number of affected myocardial segments, the faster ICA was initiated. Mean time between the suspicion of AMI on CT imaging and ICA was 196 (29–4044) minutes. Myocardial hypoperfusion on emergency CT imaging should be considered as AMI until proven otherwise, independent of the clinical scenario leading to performance of CT imaging and whether imaging was performed for the exclusion of non-cardiac pathologies. Early initiation of further diagnostic workup may potentially avoid delays to invasive treatment and reduce the CT-to-catheter-time. Our study explicitly underlines that myocardial hypoperfusion upon contrast enhanced CT imaging needs to be considered as sign of acute myocardial infarction and indicates targeted clinical workup to rule out this diagnosis and to shorten the timeframe from imaging diagnosis to interventional treatment. [ABSTRACT FROM AUTHOR]

Normal pressure hydrocephalus (NPH) is associated with a reduction in cerebral blood flow and an ischemic metabolic state. Ischemia should exhaust the available autoregulation in an attempt to correct the metabolic imbalance. There is evidence of some retained autoregulation reserve in NPH. The aim of this study is to model the cerebral autoregulation in NPH to discover a solution to this apparent paradox. A lumped parameter model was developed utilizing the known limits of autoregulation in man. The model was tested by predicting the cerebral blood volume changes which would be brought about by changes in resistance. NPH and the post shunt state were then modeled using the known constraints provided from the literature. The model successfully predicted the cerebral blood volume changes brought about by altering the cerebral perfusion pressure to the limit of autoregulation. The model suggests that NPH is associated with a balanced increase in resistance within the arterial and venous outflow segments. The arterial resistance decreased after modelling shunt insertion. The model suggests that the cerebral blood flow is actively limited in NPH by arteriolar constriction. This may occur to minimize the rise in ICP by reducing the apparent CSF formation rate. [ABSTRACT FROM AUTHOR]

Vaping use has skyrocketed especially among young adults, however there is no consensus on how vaping impacts the lungs. We aimed to determine whether there were changes in lung function acutely after a standard vaping session or if there were differences in lung function metrics between a healthy never‐vaping cohort (N = 6; 27.3 ± 3.0 years) and a young asymptomatic vaping cohort (N = 14; 26.4 ± 8.0 years) indicating chronic changes. Pulmonary function measurements and impulse oscillometry were obtained on all participants. Oxygen‐enhanced and Arterial Spin Labelling MRI were used to measure specific ventilation and perfusion, respectively, before and after vaping, and in the control cohort at baseline. MRI metrics did not show any significant differences in specific ventilation or perfusion after vaping. Heart rate increased post‐vaping (68.1 ± 10.5 to 71.3 ± 8.7, p = 0.020); however, this and other metrics did not show a nicotine dose‐dependent effect. There was a significant negative correlation between BMI and change in mean perfusion post‐vaping (p = 0.003); those with normal/low BMI showing an increase in perfusion and vice versa for high BMI. This may be due to subjects lying supine during vaping inhalation. Pulmonary function metrics indicative of airways resistance showed significant differences between the vaping and control cohorts indicating early airway changes. [ABSTRACT FROM AUTHOR]

ABSTRACT Veno‐arterial extracorporeal membrane oxygenation (VA‐ECMO) is used in case of potentially reversible cardiac failure and restores systemic hemodynamics. However, whether this is followed by improvement of microcirculatory perfusion is unknown. Moreover, critically ill patients have possible pre‐existing microcirculatory perfusion disturbances. Therefore, this review provides an overview of alterations in sublingual microcirculatory perfusion in critically ill adult patients receiving VA‐ECMO support. Pubmed, Embase (Ovid), Cochrane Central Register of Controlled Trials, and Web of Science were systematically searched according to PRISMA guidelines. Studies reporting sublingual microcirculatory perfusion measurements in adult patients supported by VA‐ECMO were included. Outcome parameters included small vessel density (SVD), perfused vessel density (PVD), perfused small vessel density (PSVD), proportion of perfused vessels (PPV), microvascular flow index (MFI) and the heterogeneity index (HI). The protocol was registered at PROSPERO (CRD42021243930). The search identified 1215 studies of which 11 were included. Cardiogenic shock was the most common indication for VA‐ECMO (n=8). Three studies report increased PSVD, PPV, and MFI 24 hours after initiation of ECMO compared to pre‐ECMO. Nonetheless, microcirculatory perfusion stabilized thereafter. Four out of four studies showed higher PSVD and PPV in survivors compared to non‐survivors. Over time, survivors showed recovery of microcirculatory perfusion within hours of initiation of ECMO, whereas this was absent in non‐survivors. Notwithstanding the limited sample, VA‐ECMO seems to improve microcirculatory perfusion shortly after initiation of ECMO, especially in survivors. Further research in larger cohorts is needed to clarify the longitudinal effects of ECMO on microcirculatory perfusion. [ABSTRACT FROM AUTHOR]

Background: Gastric cancer stands as one of the most prevalent malignancies globally, conventional endoscopic specimens have been the primary means of diagnosing preoperative gastric histopathology, however, their limitations in capturing intra-tumor heterogeneity compromise their efficacy in evaluating angiogenesis. Perfusion Computed Tomography (P-CT) emerges as a pivotal functional imaging modality, facilitating objective assessment of tissue perfusion, serving as a marker of angiogenesis. So, our research objective was to evaluate the efficacy of CT perfusion imaging in the prediction of histological grades of gastric tumors using quantitative perfusion parameters such as permeability surface (PS), blood flow (BF), mean transient time (MTT), and blood volume (BV), in addition to the qualitative scoring system then comparing the findings with the histopathological results. Results: PS and BF were statistically significant predictors of the grade of differentiation, their odds ratio (OR) was (1.05, 95% CI 1.02–1.09, for each of them) (P = 0.004, P = 0.009, respectively). MTT also emerged as a significant predictor of the grade of differentiation with an OR of 0.76 (95% CI 0.57–0.93, P = 0.025). Using multivariate logistic regression model, PS was the most potent individual P-CT predictor of differentiation of the grade and the diagnosis of poorly differentiated tumors at ≥ 39 mL/100 g/min cut off point, followed by BF at ≥ 82.2 mL/100 g/min, and MTT at < 8.4 s. Regarding the qualitative scoring system P-CT, poorly differentiated tumors generally received higher scores of PS (P < 0.001), BF (P < 0.001), and BV (P = 0.017), than well and moderately differentiated tumors, however, MTT showed that poorly differentiated tumors were more frequently scored as low compared to well and moderately differentiated tumors (P < 0.001). Conclusions: P-CT is an innovative, non-invasive biomarker for predicting gastric cancer grade by quantitative and qualitative assessment by P-CT parameters (PS, BF and MTT) with particular role of PS as the strongest individual P-CT predictor of differentiation grade followed by BF and MTT at specific cut off points. [ABSTRACT FROM AUTHOR]

Introduction: While increased baseline blood pressure (BP) is a prevalent comorbidity in the acute phase of ischemic stroke, the association between baseline BP and the state of hemispheric perfusion in patients with acute small subcortical infarcts (SSIs) has not been studied in detail. The aim of this study was to investigate the relationship between baseline BP and hemispheric cerebral blood flow (CBF) in acute SSIs. Methods: This retrospective study included 101 patients with acute SSIs. Baseline hemispheric CBF was assessed through co-registration of baseline CT perfusion imaging and follow-up diffusion-weighted imaging. The association between baseline BP, CBF, and different cerebral small vessel disease (CSVD) biomarkers was assessed. Results: Baseline systolic BP (SBP) and diastolic BP (DBP) were negatively associated with contralateral hemispheric CBF after multivariate-adjusted linear analysis (SBP: β = −0.001, 95% CI: −0.002 to 0.000, p = 0.030; DBP: β = −0.002, 95% CI: −0.003∼0.001, p = 0.006). Among other CSVD biomarkers, the presence of any cerebral microbleeds showed a significant association with lower CBF in the contralateral hemisphere of the infarct lesion (r = −0.270, p = 0.035). Conclusion: In patients with acute SSIs, increased baseline BP was associated with reduced CBF in the contralateral hemisphere of the infarct lesion, which probably could be interpreted by the exacerbation of the CSVD burden, suggesting a potential mechanistic link between BP autoregulation dysfunction and the aggravation of neurovascular impairment in SSIs. [ABSTRACT FROM AUTHOR]

Aim: The use of priming fluid in the cardiopulmonary bypass causes hemodilution and increases the need for blood transfusions. Retrograde autologous priming is known to be beneficial in reducing blood transfusion and hemodilution. In this article, 38 cases were retrospectively reviewed to demonstrate the feasibility of routine retrograde autologous priming in a newly established cardiac surgery center. Materials and Methods: A total of 38 patients underwent open-heart surgery between January 2024 and July 2024. All patients were operated using a cardiopulmonary bypass machine primed with retrograde autologous blood. Perfusion and anesthesia techniques were the same for all patients. Hematocrit levels in the preoperative period, during weaning, on the first postoperative day, third day, discharge day, and 10th postoperative day were retrospectively analyzed. Postoperative hemodynamic parameters, pressor requirements, and fluid requirements were recorded. Length of stay in the hospital and intensive care unit, as well as blood requirements, were retrospectively analyzed. Results: No major bleeding and mortality was observed. Hematocrit levels during cardiopulmonary bypass ranged from 28% to 31%. The transfusion rate for per patient was 0.13 units. Conclusion: It was proven that the routine use of retrograde autologous priming, even in a newly established heart surgery institution, is safe, repeatable, and effective in decreasing hemodilution and red cell transfusion rates in cardiac operations. [ABSTRACT FROM AUTHOR]

The mechanical properties of sclera play an important role in ocular functions, protection, and disease. Modulating the sclera's properties by exogenous crosslinking offers a way to expand the tissue's range of properties for study of the possible influences on the eye's behavior and diseases such as glaucoma and myopia. The focus of this work was to evaluate the effects of genipin crosslinking targeting the porcine perilimbal sclera (PLS) since the stiffness of this tissue was previously found in a number of studies to influence the eye's intraocular pressure (IOP). The work includes experiments on tensile test specimens and whole globes. The specimen tests showed decreased strain-rate dependence and increased relaxation stress due to the cross-linker. Whole globe perfusion experiments demonstrated that eyes treated with genipin in the perilimbal region had increased IOPs compared to the control globes. Migration of the cross-linker from the target tissue to other tissues is a confounding factor in whole globe, biomechanical measurements, with crosslinking. A novel quantitative genipin assay of the trabecular meshwork (TM) was developed to exclude globes where the TM was inadvertently crosslinked. The perfusion study, therefore, suggests that elevated stiffness of the PLS can significantly increase IOP apart from effects of the TM in the porcine eye. These results demonstrate the importance of PLS biomechanics in aqueous outflow regulation and support additional investigations into the distal outflow pathways as a key source of outflow resistance. [ABSTRACT FROM AUTHOR]

Background: Hypothermic Oxygenated machine PErfusion (HOPE) can reduce ischemic reperfusion injury and improve outcomes for liver transplant recipients. However, the effect of HOPE on high‐risk extended criteria donor (ECD) and donation after circulatory death determination (DCDD) grafts is incomplete, despite the expectation that this cohort benefit maximally from HOPE. Accordingly, this paper aims to characterize the effect of HOPE on ECD and DCDD grafts. Methods: This study includes all papers comparing HOPE to static cold storage for high‐risk ECD and DCDD grafts. Systematic searches of Medline, Embase, and Scopus were completed using the terms "HOPE" OR "hypothermic oxygenated machine perfusion" AND "liver transplantation". Data were extracted and analyzed using IBM SPSS to perform the meta‐analysis. Results: A total of 2286 records were identified, with 10 meeting the inclusion criteria. Overall, the quality of evidence is heterogenous with many papers relying on retrospective controls. However, pooled analysis demonstrates HOPE to significantly reduce the rate of early allograft dysfunction, 12‐month graft failure, re‐transplantation, total biliary complications, and non‐anastomotic strictures for high‐risk grafts. Conclusions: There is good evidence that HOPE improves outcomes following liver transplantation across a number of biochemical and clinical endpoints for high‐risk grafts. Of note, the reduction in biliary complications and re‐transplantation is particularly significant given the morbidity associated with these endpoints. However, further, high‐quality prospective trials with contemporary controls and clinically relevant primary endpoints are needed to better define the impact of HOPE for this cohort of grafts. [ABSTRACT FROM AUTHOR]

To identify potentially transplantable organs in a pool of marginal kidneys, 33 porcine slaughterhouse kidneys were perfused for 4 h with whole blood. During the normothermic perfusion, plasma, urine, and tissue samples were taken. Several biomarkers for tubule injury, endothelial activation, and inflammatory response were evaluated for a potential correlation with macroscopic appearance, histology, and filtration activity. Generally, biomarker levels increased during perfusion. TLR-4, EDN-1, and NGAL were not associated with any classification. In contrast, a steeper increase in NAG and IL-6 in plasma correlated with a poor macroscopic appearance at 4 h, indicating a higher inflammatory response in the kidneys with worse macroscopy early on, potentially due to more damage at the tubules. Although long-term effects on the graft could not be assessed in this setting, early observation under machine perfusion with whole blood was feasible. It allowed the assessment of kidneys under conditions comparable to reperfusion. This setting could give surgeons further insight into the quality of marginal kidneys and an opportunity to pre-treat them. [ABSTRACT FROM AUTHOR]

Simple Summary: This study investigated how pulmonary metastases in the lungs can be assessed using a special imaging technique called contrast-enhanced ultrasound (CEUS). We analyzed data from 54 patients with confirmed cancer spread to the lungs. Our goal was to identify patterns of blood flow in the lung tumors and to compare these with the findings from tissue samples stained to highlight blood vessels. The results showed that most lung tumors had a blood supply from the bronchial arteries, with a few showing a supply from the pulmonary arteries. Additionally, most tumors showed a rapid reduction in contrast enhancement. This research helps improve the understanding of blood flow in lung tumors and could aid in developing better diagnostics strategies. Purpose: Description of the perfusion of pulmonary metastasis by contrast-enhanced ultrasound (CEUS) and their correlation with vascularization patterns represented by immunohistochemical CD34 endothelial staining. Patients and methods: The data of 54 patients with histologic proven peripheral pulmonary metastasis, investigated between 2004 and 2023 by CEUS. These CEUS parameters were evaluated: time to enhancement (TE), categorized as early pulmonary-arterial (PA) or delayed bronchial-arterial (BA) patterns; extent of enhancement (EE), either marked or reduced; homogeneity of enhancement (HE), homogeneous or inhomogeneous; and decrease of enhancement (DE), rapid washout (<120 s) or late washout (≥120 s). Additionally, tissue samples in 45 cases (83.3%) were stained with CD34 antibody for immunohistochemical analysis. Results: In total, 4 lesions (7.4 %) exhibited PA enhancement, and 50 lesions (92.6%) demonstrated BA enhancement. Furthermore, 37 lesions (68.5%) showed marked enhancement, while 17 lesions (31.5%) exhibited reduced enhancement. The enhancement was homogeneous in 28 lesions (51.86%) and inhomogeneous in 26 lesions (48.14%). Additionally, 53 lesions (98.1%) displayed a rapid washout. A chaotic vascular pattern indicative of a bronchial arterial blood supply was identified in all cases (45/45, 100%), including all 4 lesions with PA enhancement. Conclusion: Pulmonary metastases in CEUS predominantly reveal bronchial arterial enhancement and a rapid washout. Regarding EE and HE, pulmonary metastases show heterogeneous perfusion patterns. A PA enhancement in CEUS does not exclude BA neoangiogenesis. [ABSTRACT FROM AUTHOR]

Aim: To analyse the content of the nursing diagnosis ineffective peripheral tissue perfusion in patients with diabetic foot. Design: A methodological study with a quantitative approach was performed. Methods: The analysis was performed between January and May 2021 by 34 nurses with clinical/theoretical/research experience with diabetes or nursing diagnoses. These nurses evaluated the relevance, clarity and precision of 12 diagnosis‐specific etiological factors, 22 clinical indicators and their conceptual and operational definitions. Findings: All 12 etiological factors analysed were considered relevant to diagnostic identification. However, five showed inconsistencies regarding the clarity or precision of the operational definitions, requiring adjustments. Regarding the 22 clinical indicators evaluated, all of them presented a Content Validity Index (CVI) that was statistically significant. However, in the indicators, the colour does not return to lowered limb after 1 min of leg elevation, and cold foot had Content Validity Index (CVI) <0.9 regarding relevance and accuracy of operational definitions. Conclusions: Twelve etiological factors and 22 clinical indicators were validated. Thus, this study revealed new and relevant aspects characterising peripheral perfusion in patients with diabetic foot that have not yet been clinically validated. Implications for Nursing Practice: This study contributes to support the professional practice of nurses through the early identification of etiological factors and clinical indicators in persons with diabetic foot. As a proposal, we suggest the inclusion of new defining characteristics and related factors for the nursing diagnosis ineffective peripheral tissue perfusion in the NANDA‐I taxonomy. Impact: The research highlights new and relevant aspects such as etiological factors and clinical indicators to characterise peripheral perfusion in patients with diabetic foot. Based on these findings, clinical validation is recommended to confirm the relevance of the proposed elements in the population studied for greater reliability and improved diagnostic assessment for the professional practice of nurses. Reporting Method: EQUATOR guidelines were adhered to using the GRRAS checklist for reporting reliability and agreement studies. Patient or Public Contribution: No patient or public contribution. [ABSTRACT FROM AUTHOR]

Introduction: Subjective surgeon interpretation of near-infrared perfusion video is limited by low inter-observer agreement and poor correlation to clinical outcomes. In contrast, quantification of indocyanine green fluorescence video (Q-ICG) correlates with histologic level of perfusion as well as clinical outcomes. Measuring dye volume over time, however, has limitations, such as it is not on-demand, has poor spatial resolution, and is not easily repeatable. Laser speckle contrast imaging quantification (Q-LSCI) is a real-time, dye-free alternative, but further validation is needed. We hypothesize that Q-LSCI will distinguish ischemic tissue and correlate over a range of perfusion levels equivalent to Q-ICG. Methods: Nine sections of intestine in three swine were devascularized. Pairs of indocyanine green fluorescence imaging and laser speckle contrast imaging video were quantified within perfused, watershed, and ischemic regions. Q-ICG used normalized peak inflow slope. Q-LSCI methods were laser speckle perfusion units (LSPU), the base unit of laser speckle imaging, relative perfusion units (RPU), a previously described methodology which utilizes an internal control, and zero-lag normalized cross-correlation (X-Corr), to investigate if the signal deviations convey accurate perfusion information. We determine the ability to distinguish ischemic regions and correlation to Q-ICG over a perfusion gradient. Results: All modalities distinguished ischemic from perfused regions of interest; Q-ICG values of 0.028 and 0.155 (p < 0.001); RPU values of 0.15 and 0.68 (p < 0.001); and X-corr values of 0.73 and 0.24 (p < 0.001). Over a range of perfusion levels, RPU had the best correlation with Q-ICG (r = 0.79, p < 0.001) compared with LSPU (r = 0.74, p < 0.001) and X-Corr (r = 0.46, p < 0.001). Conclusion: These results demonstrate that Q-LSCI discriminates ischemic from perfused tissue and represents similar perfusion information over a broad range of perfusion levels comparable to clinically validated Q-ICG. This suggests that Q-LSCI might offer clinically predictive real-time dye-free quantification of tissue perfusion. Further work should include validation in histologic studies and human clinical trials. [ABSTRACT FROM AUTHOR]

Objectives: del Nido cardioplegia is utilized for myocardial protection in adult patients undergoing cardiac surgery; however, no standardized re-dosing protocol exists. We describe perfusion characteristics and clinical outcomes in adult cardiac surgery patients who were re-dosed with del Nido cardioplegia. Methods: Chart review was performed for adult patients undergoing cardiac surgery (specific inclusion/exclusion criteria below) who received exactly two doses of del Nido cardioplegia from 2012 to 2019; n = 542 patients. The main outcome was a composite endpoint comprised of operative mortality, myocardial infarction, post-operative cardiac support device (CSD), and postoperative decrease in ejection fraction (EF), which was analyzed via multivariable logistic regression (MVLR). A secondary analysis evaluated postoperative vasoactive-inotropic scores (VIS) via gamma log link regression (GLLR) as a more physiologic indication of myocardial recovery. Results: MVLR demonstrated that increased total cardiopulmonary bypass (CPB) time was associated with a positive composite outcome (p <.001), whereas time between doses (p =.237) and the volume of each dose was not (p =.626). GLLR also demonstrated that prolonged CBP, decreased EF, congestive heart failure at time of surgery, and low hematocrit at the start of the surgery were all associated with higher VIS. Conclusions: In this retrospective study, variations in re-dosing strategy for del Nido cardioplegia do not affect postoperative outcomes and increased CPB time is associated with increased operative mortality, myocardial infarction, need for post-operative CSDs, and reduced postoperative EF, and increased VIS, irrespective of the re-dosing strategy. Further studies are warranted to to identify additional patient and operative characteristics that predispose to complications. [ABSTRACT FROM AUTHOR]

Purpose: This case report describes a patient with a pelvic kidney associated with an aortoiliac aneurysm amenable to open repair. Methods: We chose the selective cold renal perfusion to preserve renal function. Results: Other techniques such as transient or permanent extra-anatomic bypass, extracorporeal circulation and proximal aortic double clamping are also described in this report. Conclusions: Choosing the renal perfusion technique depended on the anatomical evaluations of the kidney and the renal artery location during the preoperative period. [ABSTRACT FROM AUTHOR]

This article discusses the use of CZT SPECT systems in brain imaging applications. CZT-based detectors offer advantages such as higher contrast, energy resolution, and spatial resolution compared to traditional scintillation crystals. Preliminary studies have shown that CZT SPECT systems can reduce acquisition time without compromising image quality. CZT SPECT is particularly useful in brain perfusion imaging and dopaminergic imaging. It also has potential applications in theranostics for brain tumors. Efforts are being made to standardize protocols and collect data to further improve diagnostic accuracy and patient management. [Extracted from the article]

Contemporary quality control methods are often insufficient in predicting clinical outcomes after revascularization in lower extremity arterial disease (LEAD) patients. This study evaluates the potential of near-infrared fluorescence imaging with indocyanine green to predict the clinical outcome following revascularization. Near-infrared fluorescence imaging was performed before and within 5 days following the revascularization procedure. Clinical improvement was defined as substantial improvement of pain free walking distance, reduction of rest- and/or nocturnal pain, or tendency toward wound healing. Time-intensity curves and 8 perfusion parameters were extracted from the dorsum of the treated foot. The quantified postinterventional perfusion improvement was compared within the clinical outcome groups. Successful near-infrared fluorescence imaging was performed in 72 patients (76 limbs, 52.6% claudication, 47.4% chronic limb-threatening ischemia) including 40 endovascular- and 36 surgical/hybrid revascularizations. Clinical improvement was observed in 61 patients. All perfusion parameters showed a significant postinterventional difference in the clinical improvement group (P -values <.001), while no significant differences were seen in the group without clinical improvement (P -values.168–.929). Four parameters demonstrated significant differences in percentage improvement comparing the outcome groups (P -values within.002–.006). Near-infrared fluorescence imaging has promising additional value besides clinical parameters for predicting the clinical outcome of revascularized LEAD patients. [ABSTRACT FROM AUTHOR]

Midodrine is an oral vasopressor option that allows for discontinuation of intravenous vasopressors for patients with cardiovascular conditions. It does not have a US Food and Drug Administration-labeled indication for use in children, and there is a paucity of literature in patients ≤6 years of age. This case series describes 2 infants with complex congenital heart diseases initiated on midodrine for augmentation of systolic (SBP) or diastolic blood pressure (DBP) to increase coronary perfusion. Case 1 was initiated on midodrine on hospital day 19 at a dose of 0.5 mg (0.17 mg/kg) enterally every 8 hours that was eventually increased to 1 mg (0.33 mg/kg) every 8 hours. Case 2 was initiated on midodrine on hospital day 15 at a dose of 2.5 mg (0.49 mg/kg) enterally every 8 hours, and this was decreased to 1.25 mg (0.25 mg/kg) every 8 hours due to high SBP. Both patients were discharged home on midodrine; other than the initially high SBP for Case 2, no other adverse drug events were noted. While midodrine was effective based on clinical response in these two infants, additional studies are needed due to the lack of safety and efficacy in children <6 years of age. [ABSTRACT FROM AUTHOR]

Background: Neuromonitoring devices are often used in traumatic brain injury. The objective of this report is to raise awareness concerning variations in optimal cerebral perfusion pressure (CPPopt) determination using exploratory information provided by two neuromonitoring monitors that are part of research programs (Moberg CNS Monitor and RAUMED NeuroSmart LogO). Methods: We connected both monitors simultaneously to a parenchymal intracranial pressure catheter and recorded the pressure reactivity index (PRx) and the derived CPPopt estimates for a patient with a severe traumatic brain injury. These estimates were available at the bedside and were updated at each minute. Results: Using the Bland and Altman method, we found a mean variation of − 3.8 (95% confidence internal from − 8.5 to 0.9) mm Hg between the CPPopt estimates provided by the two monitors (limits of agreement from − 26.6 to 19.1 mm Hg). The PRx and CPPopt trends provided by the two monitors were similar over time, but CPPopt trends differed when PRx values were around zero. Also, almost half of the CPPopt estimates differed by more than 10 mm Hg. Conclusions: These wide variations recorded in the same patient are worrisome and reiterate the importance of understanding and standardizing the methodology and algorithms behind commercial neuromonitoring devices prior to incorporating them in clinical use. [ABSTRACT FROM AUTHOR]

MRI evaluation of the diabetic foot is still a challenge not only from an interpretative but also from a technical point of view. The incorporation of advanced sequences such as diffusion-weighted imaging (DWI) and dynamic contrast-enhanced (DCE) MRI into standard protocols for diabetic foot assessment could aid radiologists in differentiating between neuropathic osteoarthropathy (Charcot's foot) and osteomyelitis. This distinction is crucial as both conditions can coexist in diabetic patients, and they require markedly different clinical management and have distinct prognoses. Over the past decade, several studies have explored the effectiveness of DWI and dynamic contrast-enhanced MRI (DCE-MRI) in distinguishing between septic and reactive bone marrow, as well as soft tissue involvement in diabetic patients, yielding promising results. DWI, without the need for exogenous contrast, can provide insights into the cellularity of bone marrow and soft tissues. DCE-MRI allows for a more precise evaluation of soft tissue and bone marrow perfusion compared to conventional post-gadolinium imaging. The data obtained from these sequences will complement the traditional MRI approach in assessing the diabetic foot. The objective of this review is to familiarize readers with the fundamental concepts of DWI and DCE-MRI, including technical adjustments and practical tips for image interpretation in diabetic foot cases. [ABSTRACT FROM AUTHOR]

INTRODUCTION: Recent advances in biomarker research have improved the diagnosis and monitoring of Alzheimer's disease (AD), but in vivo biomarker‐based workflows to assess 4R‐tauopathy (4RT) patients are currently missing. We suggest a novel biomarker‐based algorithm to characterize AD and 4RTs. METHODS: We cross‐sectionally assessed combinations of cerebrospinal fluid measures (CSF p‐tau181 and t‐tau) and 18F‐PI‐2620 tau‐positron emission tomography (PET) in patients with AD (n = 64), clinically suspected 4RTs (progressive supranuclear palsy or corticobasal syndrome, n = 82) and healthy controls (n = 19). RESULTS: Elevated CSF p‐tau181 and cortical 18F‐PI‐2620 binding was characteristic for AD while normal CSF p‐tau181 with elevated subcortical 18F‐PI‐2620 binding was characteristic for 4RTs. 18F‐PI‐2620‐assessed posterior cortical hypoperfusion could be used as an additional neuronal injury biomarker in AD. DISCUSSION: The specific combination of CSF markers and 18F‐PI‐2620 tau‐PET in disease‐specific regions facilitates the biomarker‐guided stratification of AD and 4RTs. This has implications for biomarker‐aided diagnostic workflows and the advancement in clinical trials. Highlights: Novel biomarker‐based algorithm for differentiating AD and 4R‐tauopathies.A combination of CSF p‐tau181 and 18F‐PI‐2620 discriminates AD versus 4R tauopathies.Hypoperfusion serves as an additional neuronal injury biomarker in AD. [ABSTRACT FROM AUTHOR]

The myocardium and vascular system are influenced by the neurological, paracrine and endocrine systems to control blood pressure in health. Blood pressure control is crucial to maintain adequate organ perfusion and function. In disease, the homeostatic mechanisms that control these systems are dysregulated, which can lead to organ failure. Therefore, understanding the means of manipulating these systems using anaesthesia is important. The central nervous system, cardiac muscle and vascular smooth muscle all have physiological processes which can be targeted to reduce the stress response associated with their derangement. This article reviews the different pharmacological means of altering cardiac function and blood vessel calibre to improve organ perfusion. [ABSTRACT FROM AUTHOR]

In this research, we aim to investigate the feasibility of a one-stop CT energy spectrum perfusion imaging technique for chemotherapy efficacy assessment of lung cancer patients by obtaining both functional imaging parameters of energy spectrum and perfusion in one scan. From November 2018 to February 2020, a group of 23 patients with pathologically confirmed lung cancer were chosen to undergo CT energy spectrum scans both before and after treatment. The post-treatment CT perfusion data was acquired one week after the second conventional chemotherapy session. Out of the 23 patients, 15 were in the chemotherapy effective group and the remaining 8 were in the ineffective group. The reason for this group was according to recist criteria. Arterial phase iodine concentration (icap) and intravenous phase iodine concentration (icpp) of the lesions were measured, and standardized iodine base values (nic) were calculated. The maximum diameter of the tumor before and after treatment was compared to the perfusion parameters and energy spectrum parameters before and after chemotherapy in the effective group and the invalid group was compared by two tests that p<0.05. The differences between the maximum diameter of the tumor before and after chemotherapy. 2 of the 15 patients in the effective group had liquefied necrotic areas in their lesions. One-stop ct energy-spectrum perfusion imaging can show the disease progression from a functional perspective and assess the efficacy early according to the changes in perfusion parameters and energy-spectrum parameters after lung cancer treatment. [ABSTRACT FROM AUTHOR]

Pressure ulcer is considered a common and costly problem in the care of patients. Prevention and management of pressure ulcer are very important due to the high cost of treatment and the adverse consequences of pressure ulcer. This study aimed to evaluate the effect of implementing “aSSKINg” model in reducing pressure ulcer risk. This study used a before- and afterintervention quasi-experimental design. This study was performed on 60 patients who were not randomly selected and assigned in to control and study group. The data collection tool was a 3-part sheet (Braden scale, skin health assessment, and Pressure ulcer assessment). The incidence of pressure ulcer was 19 (60.0%) in the control group versus 9 (30.0%) in the study group with statistical significant differences. The most common site of pressure ulcer was coccyx (6 [31.6%]) in the control group and Heel (3 [33.3%]) in the study group. The application of “aSSKINg” model in the patients with pressure ulcers is effective in reducing the incidence and severity of pressure ulcers. [ABSTRACT FROM AUTHOR]

Background: Clinically relevant‐postoperative pancreatic fistula (CR‐POPF) is one of the dreaded complications of pancreatoduodenectomy. Vascularity of the stump of the pancreas during pancreatico‐enteric anastomosis is considered one of the major determinants of POPF. Indocyanine green (ICG) is one of the modality for vascular assessment; hence, we aimed to evaluate the role of ICG fluorescence imaging to assess the vascularity of the pancreatic stump during pancreatoduodenectomy. Methodology: The study was conducted at Kathmandu Medical College, Kathmandu, Nepal, during the period of 1 year (June 01, 2022–July 31, 2023). All of the patients who were undergoing pancreatoduodenectomy were included in the study. In all cases, intraoperatively, ICG fluorescence detection at the pancreatic stump margin was evaluated using near‐infrared light. Results: A total of 28 patients underwent PD during this period. The ICG fluorescence imaging was positive at the pancreatic stump margin in 25 out of the 28 patients (89%), and in three cases, the florescence was negative. In patients who had negative fluorescence, revision of the stump margin was performed. Clinically relevant POPF was noted in 2 out of 28 cases, which had a soft pancreas with a small duct, although the pancreatic stump margin had good ICG florescence per‐operatively. Conclusion: ICG is inexpensive and a safe dye to use in clinical practice. We can objectively assess the pancreatic stump vascularity using intraoperative ICG fluorescence imaging, thereby potentially decreasing postoperative pancreatic fistula. [ABSTRACT FROM AUTHOR]

Background Robust venous outflow (VO) profiles, measured by degree of venous opacification on pre-thrombectomy CT angiography (CTA) studies, are strongly correlated with favorable outcomes in patients with large vessel occlusion acute ischemic stroke treated by thrombectomy. However, VO measurements are laborious and require neuroimaging expertise. Objective To develop a semi-automated method to measure VO using CTA and CT perfusion imaging studies. Methods We developed a graphical interface using The Visualization Toolkit, allowing for voxel selection at the confluence and bilateral internal cerebral veins on CTA along with arterial input functions (AlFs) from both internal carotid arteries. We extracted concentration-time curves from the CT perfusion study at the corresponding locations associated with AIF and venous output function (VOF). Outcome analyses were primarily conducted by the Mann-Whitney U and Jonckheere-Terpstra tests. Results Segmentation at the pre-selected AIF and VOF locations was performed on a sample of 97 patients. 65 patients had favorable VO (VO+) and 32 patients had unfavorable VO (VO-). VO+ patients were found to have a significantly shorter VOF time to peak (8.26; 95% CI 7.07 to 10.34) than VO- patients (9.44; 95% CI 8.61 to 10.91), P=0.007. No significant difference was found in VOF curve width and the difference in time between AIF and VOF peaks. Conclusions Time to peak of VOF at the confluence of sinuses was significantly associated with manually scored venous outflow. Further studies should aim to understand better the association between arterial inflow and venous outflow, and capture quantitative metrics of venous outflow at other locations. [ABSTRACT FROM AUTHOR]

Aims This study aimed to assess the impact of adenosine on quantitative myocardial blood flow (MBF) in a rapid stress–rest protocol compared with a rest–stress protocol using 13N-ammonia positron emission tomography (PET) myocardial perfusion imaging (MPI) and to gain insights into the time dependency of such effects. Methods and results Quantitative MBF at rest (rMBF) and during adenosine-induced stress (sMBF) and myocardial flow reserve (MFR) were obtained from 331 retrospectively identified patients who underwent 13N-ammonia PET MPI for suspected chronic coronary syndrome and who all exhibited no perfusion defects. Of these, 146 (44.1%) underwent a rapid stress–rest protocol with a time interval (Δ t stress–rest) of 20 ± 4 min between adenosine infusion offset and rest imaging, as per clinical routine. The remaining 185 (55.9%) patients underwent a rest–stress protocol and served as the reference. Groups did not differ regarding demographics, risk factors, medication, left ventricular function, and calcium scores. rMBF was significantly higher in the stress–rest vs. the rest–stress group [0.80 (interquartile range 0.66–1.00) vs. 0.70 (0.58–0.83) mL·min−1·g−1, P < 0.001], and, as sMBF was identical between groups [2.52 (2.20–2.96) vs. 2.50 (1.96–3.11), P = 0.347], MFR was significantly lower in the stress–rest group [3.07 (2.43–3.88) vs. 3.50 (2.63–4.10), P = 0.007]. There was a weak correlation between Δ t stress–rest and rMBF (r = −0.259, P = 0.002) and between Δ t stress–rest and MFR (r = 0.163, P = 0.049), and the proportion of patients with abnormally high rMBF was significantly decreasing with increasing Δ t stress–rest. Conclusion Intravenously applied adenosine induces a long-lasting hyperaemic effect on the myocardium. Consequently, rapid stress–rest protocols could lead to an overestimation of rMBF and an underestimation of MFR. [ABSTRACT FROM AUTHOR]

Ex vivo lung perfusion (EVLP) enables advanced assessment of human lungs for transplant suitability. We developed a convolutional neural network (CNN)-based approach to analyze the largest cohort of isolated lung radiographs to date. CNNs were trained to process 1300 longitudinal radiographs from n = 650 clinical EVLP cases. Latent features were transformed into principal components (PC) and correlated with known radiographic findings. PCs were combined with physiological data to classify clinical outcomes: (1) recipient time to extubation of <72 h, (2) ≥ 72 h, and (3) lungs unsuitable for transplantation. The top PC was significantly correlated with infiltration (Spearman R: 0·72, p < 0·0001), and adding radiographic PCs significantly improved the discrimination for clinical outcomes (Accuracy: 73 vs 78%, p = 0·014). CNN-derived radiographic lung features therefore add substantial value to the current assessments. This approach can be adopted by EVLP centers worldwide to harness radiographic information without requiring real-time radiological expertise. [ABSTRACT FROM AUTHOR]

Drugs that induce reversible slowing of metabolic and physiological processes would have great value for organ preservation, especially for organs with high susceptibility to hypoxia- reperfusion injury, such as the heart. Using whole-organism screening of metabolism, mobility, and development in Xenopus, we identified an existing drug, SNC80, that rapidly and reversibly slows biochemical and metabolic activities while preserving cell and tissue viability. Although SNC80 was developed as a delta opioid receptor activator, we discovered that its ability to slow metabolism is independent of its opioid modulating activity as a novel SNC80 analog (WB3) with almost 1000 times less delta opioid receptor binding activity is equally active. Metabolic suppression was also achieved using SNC80 in microfluidic human organs-on-chips, as well as in explanted whole porcine hearts and limbs, demonstrating the cross-species relevance of this approach and potential clinical relevance for surgical transplantation. Pharmacological induction of physiological slowing in combi- nation with organ perfusion transport systems may offer a new therapeutic approach for tissue and organ preservation for transplantation, trauma management, and enhancing patient survival in remote and low- resource locations. [ABSTRACT FROM AUTHOR]

Purpose Methods Results Conclusion Endothelial dysfunction is a pathophysiological change preceding many cardiovascular events. Measuring improvements of endothelial function is challenging when function is already optimal, which may be remediated using a physiological challenge. This study aimed to determine whether imaging assessments can detect microvascular effects of a mixed meal tolerance test (MMTT).Twenty healthy volunteers (age ≥45 and ≤70 years) underwent two MMTTs at the beginning (Day 1) and end (Day 84) of a twelve‐week period. Imaging methods included laser speckle contrast imaging (LSCI) combined with post‐occlusive reactive hyperaemia (PORH) and local thermal hyperaemia (LTH) challenges, passive leg movement ultrasonography (PLM), and sidestream dark field microscopy (SDFM). Measurements were conducted pre‐MMTT and at 5 timepoints post‐MMTT for PLM and SDFM and 3 timepoints post‐MMTT for PORH and LTH.No consistent effects of the MMTT were detected on LSCI LTH, PLM and SDFM endpoints. LSCI PORH maximum perfusion was significantly suppressed 46, 136, and 300 min post‐MMTT administration on Day 1, while residual perfusion decreased significantly 46 and 136 min post‐MMTT on Day 1. However, when repeated on Day 84, PORH endpoints were not significantly affected by the MMTT.SDFM, PLM and LSCI LTH endpoints displayed high intra‐subject variability and did not detect consistent effects of MMTT. LSCI PORH endpoints displayed the lowest intra‐subject variability of all assessed endpoints and were affected by the MMTT on Day 1, but not on Day 84. Further standardization of methods or more robust challenges to affect vascular endpoints may be needed. [ABSTRACT FROM AUTHOR]

Background and purpose: Imaging with conventional MRI plays a pivotal role in characterization of skull base bone-intrinsic lesions, yet some lesions are very challenging. The purpose of this study is to evaluate the role of diffusion and perfusion by T2* dynamic susceptibility contrast (DSC) in characterization of such lesions. Results: Lesions showed mostly correlated with approach: Chordomas had low perfusion and intermediate to high perfusion, while chondrosarcoma had ADC value > 1.6 × 10–3/cm2 and more perfused. Metastases had variable ADC values usually intermediate with high perfusion. Plasmacytomas had similar features yet with characteristic conventional morphology and single number. Lymphoma (primary bony) had high perfusion and lowest diffusion ADC (= 04–0.7 × 10–3/cm2). Giant cell tumors and hemangiopericytomas had lowest perfusion. Conclusion: The proposed imaging approach showed very good results and high accuracy in differentiation of skull base bony lesions. [ABSTRACT FROM AUTHOR]

Postoperative tissue flap vitality monitoring enables early detection of clinical complications, allowing for intervention. Timely re-operation can prevent the need for extensive correction procedures, thus reducing healthcare costs and hospitalization time. Statistics show that monitoring can increase the success rate of flap survival to 95% or higher. However, despite the significant progress in monitoring techniques, major and minor complications, leading to the loss of the flap, still occur. This clinical application review aims to provide a comprehensive overview of the recent advancements and findings in flap surgery reconstructions, transplants, and systems for their postoperative assessment. The literature from the years 1925 to 2024 has been reviewed to capture previous and current solutions for monitoring flap vitality. Clinically acclaimed methods and experimental techniques were classified and reviewed from a technical and clinical standpoint. Physical examination, metabolism change, ultrasound method, and electromagnetic (EM) radiation-based measurement methods were carefully evaluated from the perspective of their considered applications. Guidelines aiding engineers in the future design and development process of monitoring systems were proposed. This paper provides a comprehensive overview of the monitoring techniques used in postoperative flap vitality monitoring. It also gives an overview of each approach and potential ways for future development. [ABSTRACT FROM AUTHOR]

We previously reported that normothermic ex vivo kidney perfusion (NEVKP) is superior in terms of organ protection compared to static cold storage (SCS), which is still the standard method of organ preservation, but the mechanisms are incompletely understood. We used a large animal kidney autotransplant model to evaluate mitochondrial function during organ preservation and after kidney transplantation, utilizing live cells extracted from fresh kidney tissue. Male porcine kidneys stored under normothermic perfusion showed preserved mitochondrial function and higher ATP levels compared to kidneys stored at 4 °C (SCS). Mitochondrial respiration and ATP levels were further enhanced when AP39, a mitochondria-targeted hydrogen sulfide donor, was administered during warm perfusion. Correspondingly, the combination of NEVKP and AP39 was associated with decreased oxidative stress and inflammation, and with improved graft function after transplantation. In conclusion, our findings suggest that the organ-protective effects of normothermic perfusion are mediated by maintenance of mitochondrial function and enhanced by AP39 administration. Activation of mitochondrial function through the combination of AP39 and normothermic perfusion could represent a new therapeutic strategy for long-term renal preservation. The authors previously reported that normothermic ex vivo kidney perfusion is superior to static cold storage in terms of organ protection, but the detailed mechanism was unclear. Here the authors show that the organ-protective effects of normothermic perfusion are mediated by maintenance of mitochondrial function and enhanced by administration of AP39, a mitochondria-targeted hydrogen sulfide donor. [ABSTRACT FROM AUTHOR]

Background: Ictal brain perfusion SPECT provides higher sensitivity for the identification of the epileptic seizure onset zone (SOZ) than interictal SPECT. However, ictal SPECT is demanding due to the unpredictable waiting period for the next seizure to allow for ictal tracer injection. Thus, starting with an interictal scan and skipping the ictal scan if the interictal scan provides a SOZ candidate with high confidence could be an efficient approach. The current study estimated the rate of high-confidence SOZ candidates and the false lateralization rate among them for interictal and ictal SPECT. Methods: 177 patients (48% females, median age 38y, interquartile range 27–48y) with ictal and interictal SPECT acquired with 99mTc-HMPAO (n = 141) or -ECD (n = 36) were included retrospectively. The vast majority of the patients was suspected to have temporal lobe epilepsy. Visual interpretation of the SPECT data was performed independently by 3 readers in 3 settings: "interictal only" (interictal SPECT and statistical hypoperfusion map), "ictal only" (ictal SPECT and hyperperfusion map), and "full" setting (side-by-side interpretation of ictal and interictal SPECT including statistical maps and SISCOM analysis). The readers lateralized the SOZ (right, left, none) and characterized their confidence using a 5-score. A case was considered "lateralizing with high confidence" if all readers lateralized to the same hemisphere with at least 4 of 5 confidence points. Lateralization of the SOZ in the "full" setting was used as reference standard. Results: The proportion of "lateralizing with high confidence" cases was 4.5/31.6/38.4% in the "interictal only"/"ictal only"/"full" setting. One (12.5%) of the 8 cases that were "lateralizing with high confidence" in the "interictal only" setting lateralized to the wrong hemisphere. Among the 56 cases that were "lateralizing with high confidence" in the "ictal only" setting, 54 (96.4%) were also lateralizing in the "full" setting, all to the same hemisphere. Conclusions: Starting brain perfusion SPECT in the presurgical evaluation of epilepsy with an interictal scan to skip the ictal scan in case of a high-confidence interictal SOZ candidate is not a useful approach. In contrast, starting with an ictal scan to skip the interictal scan in case of a high-confidence ictal SOZ candidate can be recommended. [ABSTRACT FROM AUTHOR]