Search

PURPOSE: Conventional contrast-enhanced MRI is currently the primary imaging technique used to evaluate radiation treatment response in meningiomas. However, newer perfusion-weighted MRI techniques, such as 3D pseudocontinuous arterial spin labeling (3D pCASL) MRI, capture physiologic information beyond the structural information provided by conventional MRI and may provide additional complementary treatment response information. The purpose of this study is to assess 3D pCASL for the evaluation of radiation-treated meningiomas. METHODS: Twenty patients with meningioma treated with surgical resection followed by radiation, or by radiation alone, were included in this retrospective single-institution study. Patients were evaluated with 3D pCASL and conventional contrast-enhanced MRI before and after radiation (median follow up 6.5 months). Maximum pre- and post-radiation ASL normalized cerebral blood flow (ASL-nCBF) was measured within each meningioma and radiation-treated meningioma (or residual resected and radiated meningioma), and the contrast-enhancing area was measured for each meningioma. Wilcoxon signed-rank tests were used to compare pre- and post-radiation ASL-nCBF and pre- and post-radiation area. RESULTS: All treated meningiomas demonstrated decreased ASL-nCBF following radiation (p

High-molecular-weight linear polymers (HMWLPs) have earned the name "drag-reducing polymers" because of their ability to reduce drag in turbulent flows. Recently, these polymers have become popular in bioengineering applications. This study investigated whether the addition of HMWLP in a venoarterial extracorporeal circulation (ECC) model could improve microvascular perfusion and oxygenation. Golden Syrian hamsters were instrumented with a dorsal skinfold window chamber and subjected to ECC using a circuit comprised of a peristaltic pump and a bubble trap. The circuit was primed with lactated Ringer solution (LR) containing either 5 ppm of polyethylene glycol (PEG) with a low molecular weight of 500 kDa (PEG500k) or 5 ppm of PEG with a high molecular weight of 3,500 kDa (PEG3500k). After 90 min of ECC at 15% of the animal's cardiac output, the results showed that the addition of PEG3500k to LR improved microvascular blood flow in arterioles and venules acutely (2 h after ECC), whereas functional capillary density showed improvement up to 24 h after ECC. Similarly, PEG3500k improved venular hemoglobin O2 saturation on the following day after ECC. The serum and various excised organs all displayed reduced inflammation with the addition of PEG3500k, and several of these organs also had a reduction in markers of damage with the HMWLPs compared to LR alone. These promising results suggest that the addition of small amounts of PEG3500k can help mitigate the loss of microcirculatory function and reduce the inflammatory response from ECC procedures.NEW & NOTEWORTHY High-molecular-weight linear polymers have gained traction in bioengineering applications. The addition of PEG3500k to lactated Ringer solution (LR) improved microvascular blood flow in arterioles and venules acutely after extracorporeal circulation (ECC) in a hamster model and improved functional capillary density up to 24 h after ECC. PEG3500k improved venular hemoglobin O2 saturation and oxygen delivery acutely after ECC and reduced inflammation in various organs compared to LR alone.

Stroke alters blood flow to the brain resulting in damaged tissue and cell death. Moreover, the disruption of cerebral blood flow (perfusion) can be observed in areas surrounding and distal to the lesion. These structurally preserved but suboptimally perfused regions may also affect recovery. Thus, to better understand aphasia recovery, the relationship between cerebral perfusion and language needs to be systematically examined. In the current study, we aimed to evaluate (i) how stroke affects perfusion outside of lesioned areas in chronic aphasia and (ii) how perfusion in specific cortical areas and perilesional tissue relates to language outcomes in aphasia. We analysed perfusion data from a large sample of participants with chronic aphasia due to left hemisphere stroke (n = 43) and age-matched healthy controls (n = 25). We used anatomically defined regions of interest that covered the frontal, parietal, and temporal areas of the perisylvian cortex in both hemispheres, areas typically known to support language, along with several control regions not implicated in language processing. For the aphasia group, we also looked at three regions of interest in the perilesional tissue. We compared perfusion levels between the two groups and investigated the relationship between perfusion levels and language subtest scores while controlling for demographic and lesion variables. First, we observed that perfusion levels outside the lesioned areas were significantly reduced in frontal and parietal regions in the left hemisphere in people with aphasia compared to the control group, while no differences were observed for the right hemisphere regions. Second, we found that perfusion in the left temporal lobe (and most strongly in the posterior part of both superior and middle temporal gyri) and inferior parietal areas (supramarginal gyrus) was significantly related to residual expressive and receptive language abilities. In contrast, perfusion in the frontal regions did not show such a relationship; no relationship with language was also observed for perfusion levels in control areas and all right hemisphere regions. Third, perilesional perfusion was only marginally related to language production abilities. Cumulatively, the current findings demonstrate that blood flow is reduced beyond the lesion site in chronic aphasia and that hypoperfused neural tissue in critical temporoparietal language areas has a negative impact on behavioural outcomes. These results, using perfusion imaging, underscore the critical and general role that left hemisphere posterior temporal regions play in various expressive and receptive language abilities. Overall, the study highlights the importance of exploring perfusion measures in stroke.

Therapeutic oligonucleotides (ONs) are typically manufactured via solid-phase synthesis, characterized by limited scalability and huge environmental footprint, limiting their availability. Biomanufactured ONs have the potential to reduce the immunogenic side-effects, and to improve the sustainability of their chemical counterparts. Rhodovulum sulfidophilum was demonstrated a valuable host for the extracellular production of recombinant ONs. However, low viable cell densities and product titer were reported so far. In this work, perfusion cell cultures were established for the intensification of ON biomanufacturing. First, the perfusion conditions were simulated in 50 mL spin tubes, selected as a scale-down model of the process, with the aim of optimizing the medium composition and process parameters. This optimization stage led to an increase in the cell density by 44 % compared to the reference medium formulation. In addition, tests at increasing perfusion rates were conducted until achieving the maximum viable cell density (VCD max), allowing the determination of the minimum cell-specific perfusion rate (CSPR min) required to sustain the cell culture. Intriguingly, we discovered in this system also a maximum CSPR, above which growth inhibition starts. By leveraging this process optimization, we show for the first time the conduction of perfusion cultures of R. sulfidophilum in bench-scale bioreactors. This process development pipeline allowed stable cultures for more than 20 days and the continuous biomanufacturing of ONs, testifying the great potential of perfusion processes. • Medium composition and design space defined for perfusion cultures of Rhodovulum sulfidophilum. • Process scaled up to a 2 L bioreactor with ATF and effect of perfusion rate investigated. • Stable perfusion cultures for >20 days, with cell densities lager than in fed-batch. • Oligonucleotides continuously harvested, with titers 2 orders of magnitudes larger than literature. • First report on continuous biomanufacturing of oligonucleotides. [ABSTRACT FROM AUTHOR]

The paper-based culture platform developed by Whitesides readily incorporates tissue-like structures into laboratories with established workflows that rely on monolayer cultures. Cell-laden hydrogels are deposited in these porous scaffolds with micropipettes; these scaffolds support the thin gel slabs, allowing them to be evaluated individually or stacked into thick constructs. The paper-based culture platform has inspired many basic and translational studies, each exploring how readily accessible materials can generate complex structures that mimic aspects of tissues in vivo. Many of these examples have relied on static culture conditions, which result in diffusion-limited environments and cells experiencing pericellular hypoxia. Perfusion-based systems can alleviate pericellular hypoxia and other cell stresses by continually exposing the cells to fresh medium. These perfusion systems are common in microfluidic and organ-on-chip devices supporting cells as monolayer cultures or as 3D constructs. Here, we introduce a continuous flow delivery system, which uses parts readily produced with 3D printing to provide a self-contained culture platform in which cells in paper or other scaffolds are exposed to fresh (flowing) medium. We demonstrate the utility of this device with examples of cells maintained in single cell-laden scaffolds, stacks of cell-laden scaffolds, and scaffolds that contain monolayers of endothelial cells. These demonstrations highlight some possible experimental questions that can be enabled with readily accessible culture materials and a perfusion-based device that can be readily fabricated. [ABSTRACT FROM AUTHOR]

Introduction Continuous extracorporeal perfusion (ECP), or machine perfusion, holds promise for prolonged skeletal muscle preservation in limb ischemia-reperfusion injury. This study aimed to extend the amputation-to-replantation time window from currently 6 hours to 33 hours using a 24-hour ECP approach. Materials and Methods Six large white pigs underwent surgical forelimb amputation under general anesthesia. After amputation, limbs were kept for 9 hours at room temperature and then perfused by 24-hour ECP with a modified histidine-tryptophan-ketoglutarate (HTK) solution. After ECP, limbs were orthotopically replanted and perfused in vivo for 12 hours. Clinical data, blood, and tissue samples were collected and analyzed. Results All 6 forelimbs could be successfully replanted and in vivo reperfused for 12 hours after 9 hours of room temperature ischemia followed by 24 hours ECP. Adequate limb perfusion was observed after replantation as shown by thermography and laser Doppler imaging. All pigs survived without severe organ failure, and no significant increase in inflammatory cytokines was found. Macroscopy and histology showed marked interstitial muscular edema of the limbs, whereas myofiber necrosis was not evident, implying the preservation of muscular integrity. Conclusions The use of a 24-hour ECP has successfully extended limb preservation to 33 hours. The modified histidine-tryptophan-ketoglutarate perfusate demonstrated its ability for muscle protection. This innovative approach not only facilitates limb replantation after combat injuries, surmounting geographical barriers, but also broadens the prospects for well-matched limb allotransplants across countries and continents. [ABSTRACT FROM AUTHOR]

Background and Purpose Methods Results Conclusions Ischemic strokes due to isolated posterior cerebral artery (PCA) occlusions represent 5% of all strokes but have significant impacts on patients’ quality of life, primarily due to visual deficits and thalamic involvement. Current guidelines for acute PCA occlusion management are sparse, and the prognostic value of perfusion imaging parameters remains underexplored.We conducted a retrospective analysis of 32 patients with isolated PCA occlusions treated at Johns Hopkins Medical Institutions between January 2017 and March 2023. Patients underwent pretreatment perfusion imaging, with perfusion parameters analyzed using RAPID software. The primary outcome was short‐term clinical outcome as measured by the National Institutes of Health Stroke Scale (NIHSS) at discharge.The median age of the cohort was 70 years, with 34% female and 66% male. Significant correlations were found between NIHSS at discharge and various perfusion parameters, including time‐to‐maximum (Tmax) >6 seconds (ρ = .55, p = .004), Tmax >8 seconds (ρ = .59, p = .002), Tmax >10 seconds (ρ = .6, p = .001), mismatch volume (ρ = .51, p = .008), and cerebral blood volume (CBV) < 34% (ρ = .59, p = .002).Tmax and CBV volumes significantly correlated with discharge NIHSS with marginal superiority of Tmax >10 seconds and CBV <42% volumes. These findings suggest that CT and MR perfusion imaging can play a crucial role in the acute management of PCA strokes, though larger, standardized studies are needed to validate these results and refine imaging thresholds specific to posterior circulation infarcts. [ABSTRACT FROM AUTHOR]

Aging is associated with inspiratory muscle dysfunction; however, the impact of aging on diaphragm blood flow (BF) regulation, and whether sex differences exist, is unknown. We tested the hypotheses in young animals that diaphragm BF and vascular conductance (VC) would be greater in females and that aging would decrease the diaphragm's ability to increase BF with contractions. Young (4–6 mo) and old (22–24 mo) Fischer 344 rats were divided into four groups: young female (YF, n = 7), young male (YM, n = 8), old female (OF, n = 9), and old male (OM, n = 9). Diaphragm BF (mL/min/100 g) and VC (mL/mmHg/min/100 g) were determined, via fluorescent microspheres, at rest and during 1 Hz contractions. In YF versus OF, aging blunted the increase in medial costal diaphragm BF (44 ± 5% vs. 16 ± 12%; P < 0.05) and VC (43 ± 7% vs. 21 ± 12%; P < 0.05). Similarly, in YM versus OM, aging blunted the increase in medial costal diaphragm BF (43 ± 6% vs. 24 ± 12%; P < 0.05) and VC (50 ± 6% vs. 34 ± 10%; P < 0.05). In female rats, age increased dorsal costal diaphragm BF, whereas in male rats, age increased crural diaphragm BF (P < 0.05). Compared with age-matched females, dorsal costal diaphragm BF was lower in YM and OM (P < 0.05). In conclusion, aging results in an inability to augment medial costal diaphragm BF and alters regional diaphragm BF distribution in response to muscular contractions. Furthermore, sex differences in regional diaphragm BF are present in young and old animals. NEW & NOTEWORTHY: This is the first study, to our knowledge, to demonstrate that old age impairs the hyperemic response and alters blood flow distribution in the diaphragm of both female and male rats. In addition, this investigation provides novel evidence of sex differences in regional diaphragm blood flow distribution with contractions. The data presented herein suggest that aging compromises diaphragm vascular function and provides a potential mechanism for the diaphragm contractile dysfunction associated with old age. [ABSTRACT FROM AUTHOR]

Ultrasound imaging is inexpensive, portable, and widely available. The development of a real-time transcutaneous spinal cord perfusion monitoring system would allow more precise targeting of mean arterial pressure goals following acute spinal cord injury (SCI). There has been no prior demonstration of successful real-time cord perfusion monitoring in humans. Four adult patients who had undergone posterior cervical decompression and instrumentation at a single center were enrolled into this prospective feasibility study. All participants had undergone cervical laminectomies spanning ≥2 contiguous levels ≥2 months prior to inclusion with no history of SCI. The first 2 underwent transcutaneous ultrasound without contrast and the second 2 underwent contrast-enhanced ultrasound (CEUS) with intravenously injected microbubble contrast. Using noncontrast ultrasound with or without Doppler (n = 2), the dura, spinal cord, and vertebral bodies were apparent however ultrasonography was insufficient to discern intramedullary perfusion or clear white-gray matter differentiation. With application of microbubble contrast (n = 2), it was possible to quantify differential spinal cord perfusion within and between cross-sectional regions of the cord. Further, it was possible to quantify spinal cord hemodynamic perfusion using CEUS by measuring peak signal intensity and the time to peak signal intensity after microbubble contrast injection. Time-intensity curves were generated and area under the curves were calculated as a marker of tissue perfusion. CEUS is a viable platform for monitoring real-time cord perfusion in patients who have undergone prior cervical laminectomies. Further development has the potential to change clinical management acute SCI by tailoring treatments to measured tissue perfusion parameters. [ABSTRACT FROM AUTHOR]

Background: Normothermic machine perfusion (NMP) allows for the assessment and resuscitation of ex‐vivo human livers prior to transplantation. Commercially available NMP systems are closed circuits that accumulate metabolic waste and cytokines over time, potentially limiting organ preservation times. Dialysis has been proposed as a method to remove waste and excess fluid from such systems. This study aimed to demonstrate the utility of integrating dialysis into a commercially available system by quantifying solute removal. Methods: A dialysis filter was attached in parallel to a commercially available liver perfusion system. Three livers declined for transplantation were split before undergoing long‐term NMP with blood using the modified system. During perfusion, dialysate flow rates were set in the range of 100–600 mL/h for short periods of time. At each flow rate, perfusate and spent dialysate samples were collected and analyzed for solute clearance. Results: The addition of dialysis to a commercial NMP system removed water‐soluble waste and helped regulate electrolyte concentrations. Interleukin‐6 was successfully removed from the perfusate. Solute clearance was proportional to dialysate flow rate. A guide for our perfusion setup was created for the appropriate selection of dialysis flow rates and duration based on real‐time perfusate composition. Conclusions: Dialysis circuits can efficiently remove waste and regulate perfusate composition, and can be easily incorporated to improve the performance of commercially available systems. Quantification of the effect of dialysis on perfusate composition enables refined dialysis control to optimize electrolyte profiles and avoid the over‐ or under‐correction of key solutes. [ABSTRACT FROM AUTHOR]

Background: The global incidence of liver diseases is rising, yet there remains a dearth of precise research models to mimic these diseases. The use of normothermic machine perfusion (NMP) to study diseased livers recovered from liver transplantation (LT) recipients presents a promising avenue. Accordingly, we have developed a machine perfusion system tailored specifically for the human whole diseased livers and present our experience from the NMP of diseased livers. Methods: Six diseased livers recovered from LT recipients with different diagnoses were collected. The diseased livers were connected to the machine perfusion system that circulated tailored perfusate, providing oxygen and nutrients. The pressure and flow of the system were recorded, and blood gas analysis and laboratory tests of perfusate and bile were examined to analyze the function of the diseased livers. Liver tissues before and after NMP were collected for histological analysis. Results: Experiments showed that the system maintained the diseased livers in a physiological state, ensuring stable hemodynamics and a suitable partial pressure of oxygen and carbon dioxide. The results of blood gas analysis and laboratory tests demonstrated a restoration and sustenance of metabolism with minimal damage. Notably, a majority of the diseased livers exhibited bile production continuously, signifying their vivid functional integrity. The pathological characteristics remained stable before and after NMP. Conclusion: We successfully established the machine perfusion system tailored specifically for diseased human whole livers. Through the application of this system, we have developed a novel in vitro model that faithfully recapitulates the main features of human liver disease. This model holds immense promise as an advanced disease modeling platform, offering profound insights into liver diseases and potential implications for research and therapeutic development. [ABSTRACT FROM AUTHOR]

Background: The role of intraoperative near-infrared fluorescence angiography with indocyanine green in reducing anastomotic leakage (AL) has been demonstrated in colorectal surgery, however, its perfusion assessment mode, and efficacy in reducing anastomotic leakage after laparoscopic intersphincteric resection (LsISR) need to be further elucidated. Aim: Aim was to study near-infrared fluorescent angiography to help identify bowel ischemia to reduce AL after LsISR. Material and methods: A retrospective case-matched study was conducted in one referral center. A total of 556 consecutive patients with ultra-low rectal cancer including 140 patients with fluorescence angiography of epiploic appendages (FAEA)were enrolled. Perfusion assessment by FAEA in the monochrome fluorescence mode. Patients were divided into two groups based on perfusion assessment by FAEA. The primary endpoint was the AL rate within 6 months, and the secondary endpoint was the structural sequelae of anastomotic leakage (SSAL). Results: After matching, the study group (n = 109) and control group (n = 190) were well-balanced. The AL rate in the FAEA group was lower before (3.6% vs. 10.1%, P = 0.026) and after matching (3.7% vs. 10.5%, P = 0.036). Propensity scores matching analysis (OR 0.275, 95% CI 0.035–0.937, P 0.039), inverse probability of treatment weighting (OR 0.814, 95% CI 0.765–0.921, P 0.002), and regression analysis (OR 0.298, 95% CI 0.112–0.790, P = 0.015), showed that FAEA was an independent protector factor for AL. This technique can significantly shorten postoperative hospital stay [9 (6–13) vs. 10 (8–13), P = 0.024] and reduce the risk of SSAL (1.4% vs. 6.0%, P = 0.029). Conclusions: Perfusion assessment by FAEA can achieve better visualization in LsISR and reduce the incidence of AL, subsequently avoiding SSAL after LsISR. [ABSTRACT FROM AUTHOR]

Background: Anastomotic leakage (AL) is a dreaded complication following colorectal cancer surgery, impacting patient outcome and leads to increasing healthcare consumption as well as economic burden. Bowel perfusion is a significant modifiable factor for anastomotic healing and thus crucial for reducing AL. Aims: The study aimed to calculate a cut-off value for quantified laser speckle perfusion units (LSPUs) in order to differentiate between ischemic and well-perfused tissue and to assess inter-observer reliability. Methods: LSCI was performed using a porcine ischemic small bowel loop model with the PerfusiX-Imaging® system. An ischemic area, a well-perfused area, and watershed areas, were selected based on the LSCI colormap. Subsequently, local capillary lactate (LCL) levels were measured. A logarithmic curve estimation tested the correlation between LSPU and LCL levels. A cut-off value for LSPU and lactate was calculated, based on anatomically ischemic and well-perfused tissue. Inter-observer variability analysis was performed with 10 observers. Results: Directly after ligation of the mesenteric arteries, differences in LSPU values between ischemic and well-perfused tissue were significant (p < 0.001) and increased significantly throughout all following measurements. LCL levels were significantly different (p < 0.001) at both 60 and 120 min. Logarithmic curve estimation showed an R2 value of 0.56 between LSPU and LCL values. A LSPU cut-off value was determined at 69, with a sensitivity of 0.94 and specificity of 0.87. A LCL cut-off value of 3.8 mmol/L was found, with a sensitivity and specificity of 0.97 and 1.0, respectively. There was no difference in assessment between experienced and unexperienced observers. Cohen's Kappa values were moderate to good (0.52–0.66). Conclusion: Real-time quantification of LSPUs may be a feasible intraoperative method to assess tissue perfusion and a cut-off value could be determined with high sensitivity and specificity. Inter-observer variability was moderate to good, irrespective of prior experience with the technique. [ABSTRACT FROM AUTHOR]

Lipomatous soft tissue tumors (STT), ranging from benign lipomas to malignant liposarcomas, require accurate differentiation for timely treatment. Complementary to MRI, Contrast-enhanced ultrasound (CEUS) is emerging as a promising tool, providing insight into tumor microperfusion in real-time. This study aims to explore the potential of preoperative CEUS in differentiating benign lipomatous tumors from malignant liposarcoma subtypes. Eighty-seven patients with lipomatous STT scheduled for surgery were enrolled. Clinical and MRI assessments were conducted to obtain general tumor characteristics. CEUS was used for a standardized tumor perfusion evaluation. Perfusion analysis included peak enhancement, rise time, wash-in perfusion index, and wash-out rate, reflecting the perfusion kinetics. Histopathological results were obtained for every STT and compared to perfusion characteristics. In total, 48 lipoma, 23 ALT and 11 liposarcoma were identified. Significant differences in tumor microperfusion were demonstrated, with higher perfusion levels indicating higher malignancy (Peak enhancement [a.u.] of Lipoma: 145 ± 238; ALT: 268 ± 368; Liposarcoma: 3256 ± 4333; p (ALT vs. Liposarcoma) < 0.001). A perfusion-based identification of a benign lipoma or ALT versus sarcoma resulted in a positive predictive value of 93%. Patient-related factors (age, gender, BMI, ASA score, smoking status) had no significant impact on the CEUS-based perfusion parameters. Our study suggests CEUS as a capable non-invasive tool for improving preoperative assessment of lipomatous STT. It can assist in the distinction between benign and malignant STT, accelerating treatment decisions and enhancing patient outcomes. Significant correlations between CEUS-derived parameters and malignancy highlight its risk assessment potential. [ABSTRACT FROM AUTHOR]

Background Regarding the less-known effects of beta-blocker consumption on the diagnostic value of the myocardial perfusion scan with dipyridamole stress in coronary artery disease (CAD), we aimed to compare the findings of the scans done on the beta-blocker consumption course and after discontinuation of this medications. Materials and Methods Thirty patients with probably CAD and abnormal myocardial perfusion scans (presence of reversible defect), who had been treated with beta-blockers for at least 3 months, were studied. Dipyridamole stress phase of myocardial perfusion single-photon emission computed tomography (SPECT) was performed two times with an interval of about 1 week, once after discontinuation of all antianginal and anti-ischemic medications, statins, and beta-blockers for 72 hours prior to the study, and again after discontinuation of all these medications except for beta-blockers. Imaging was done with the same protocol, radiopharmaceutical dose, and imaging parameters. Summed stress score (SSS), summed stress rest, and summed difference scores (SDS), total perfusion deficit (TPD), severity, and extension of myocardial perfusion defects in three coronary artery territories were analyzed, using quantitative perfusion SPECT software. Results Most variables such as SSS, SDS, TPD, severity, and extension of defects showed a significant difference between the two conditions including beta-blocker consumption and after discontinuing beta-blocker consumption before stress imaging (p < 0.05). Moreover, in patients on treatment with metoprolol, all studied factors including SSS, SDS, TPD, severity, and extension of perfusion defects were significantly reduced when patients consumed beta-blockers before SPECT evaluation (p < 0.05). Conclusion Beta-blocker consumption can lead to a decrease in the severity and extent of myocardial perfusion defects and therefore probably a decrease in the sensitivity of myocardial scans. Discontinuation of beta-blocker prior to the dipyridamole myocardial perfusion scan can improve diagnostic accuracy. [ABSTRACT FROM AUTHOR]

In free flap reconstruction, improving flap tolerance to warm ischemia (WI) is fundamental. WI is the result of a venous or arterial thrombosis, which can only be addressed through surgical revision. No additional treatments have shown superior efficacy at salvaging free flaps after or during WI. Custom perfusion machines (PM), used to reduce the intensity of lesions of the flap stored in cold ischemia, have not been evaluated for WI flap salvage. This proof-of-concept study assessed whether the Lifeport® perfusion machine could improve the salvage procedure's success rates after one hour of venous WI. Five different groups were evaluated with four porcine latissimus dorsi free flaps included in each group. Depending on the group, the flaps were subjected to one hour of WI followed by revascularization, static hypothermic submersion, or dynamic Lifeport® perfusion. Additionally, two flap perfusion liquids were evaluated: KPS-1® and IGL-1®. Biopsies were performed before in vivo warm ischemia of the flap, after in vivo warm ischemia of the flap, and after one and two hours of preservation. Interstitial edema, muscular cell size and muscular diffuse necrosis were quantified by histological assessment. Static submersion did not demonstrate any efficacy for venous flap salvage. Dynamic perfusion on Lifeport® machine showed a significant improvement in tissue parameters. Thrombi and fibrine, present during the WI period, were no longer visible inside vessels and the perfusion machine flow evacuated the inflammatory cells and their substrates from the flap. The flap weights did not increase during perfusion time, confirming the benefits of the Lifeport® perfusion machine. Evaluating Lifeport® advantages on human free flap salvage is necessary to confirm the benefits for the tissue and to increase post-operative results after congestive free flap revision surgery. [ABSTRACT FROM AUTHOR]

The extent of perfusion of a deep inferior epigastric artery perforator (DIEP) flap is a primary concern for surgeons. This study aimed to determine whether the flap area or volume can be estimated using perforator and flap characteristics. Intraoperative flap perfusion was assessed using indocyanine green angiography in patients who underwent DIEP flap breast reconstruction between November 2018 and February 2023. The area perfused by a single dominant perforator was delineated on the surface of the flap and measured using the ImageJ software. Multiple linear regression analysis was conducted to estimate the 'perfusion ratio,' defined as the perfused area divided by the total flap area. Potential predictor variables included flap size (cm2), flap thickness (mm), perforator diameter (mm), perforator rows (medial/lateral), vertical location of perforator (at or above/below the umbilicus), and perforator eccentricity (vertical distance from upper flap margin to perforator, cm). In total, 101 patients were included in this analysis. The mean 'perfusion ratio' was 67.8% ± 11.5%, predicted by perforator diameter (p = 0.022) and vertical location below umbilicus (p < 0.001) with positive correlations and negatively correlated with flap thickness (p = 0.003) in the multivariable analysis. Both perfusion area and weight were predicted by perforator diameter, vertical location of perforator, flap size, and flap thickness (p < 0.001). The coefficient of determination (adjusted R2) for prediction of perfusion weight was higher than that for the perfusion area (75.5% vs. 69.4%). Flap volume, rather than area, is determined by a perforator of a given diameter and location. [ABSTRACT FROM AUTHOR]

Background: Capnography is a monitoring tool that is increasingly available in veterinary practice, providing valuable information regarding ventilatory status and tissue perfusion. While its main use is during general anaesthesia, capnography can also be applied in conscious/sedated animals. Aim of the article: This article describes how capnography works, the different devices available, and how to interpret the information provided. A discussion regarding troubleshooting is presented to help identify and solve common issues that may arise while using capnography. [ABSTRACT FROM AUTHOR]

Arterial spin labeling (ASL) and dynamic susceptibility contrast (DSC) magnetic resonance imaging (MRI) have shown potential for differentiating tumor progression from pseudoprogression. For pseudocontinuous ASL with a single postlabeling delay, the presence of delayed arterial transit times (ATTs) could affect the evaluation of ASL‐MRI perfusion data. In this study, the influence of ATT artifacts on the perfusion assessment and differentiation between tumor progression and pseudoprogression were studied. This study comprised 66 adult patients (mean age 60 ± 13 years; 40 males) with a histologically confirmed glioblastoma who received postoperative radio (chemo)therapy. ASL‐MRI and DSC‐MRI scans were acquired at 3 months postradiotherapy as part of the standard clinical routine. These scans were visually scored regarding (i) the severity of ATT artifacts (%) on the ASL‐MRI scans only, scored by two neuroradiologists; (ii) perfusion of the enhancing tumor lesion; and (iii) radiological evaluation of tumor progression versus pseudoprogression by one neuroradiologist. The final outcome was based on combined clinical and radiological follow‐up until 9 months postradiotherapy. ATT artifacts were identified in all patients based on the mean scores of two raters. A significant difference between the radiological evaluation of ASL‐MRI and DSC‐MRI was observed only for ASL images with moderate ATT severity (30%–65%). The perfusion assessment showed ASL‐MRI tending more towards hyperperfusion than DSC‐MRI in the case of moderate ATT artifacts. In addition, there was a significant difference between the prediction of tumor progression with ASL‐MRI and the final outcome in the case of severe ATT artifacts (McNemar test, p = 0.041). Despite using ASL imaging parameters close to the recommended settings, ATT artifacts frequently occur in patients with treated brain tumors. Those artifacts could hinder the radiological evaluation of ASL‐MRI data and the detection of true disease progression, potentially affecting treatment decisions for patients with glioblastoma. [ABSTRACT FROM AUTHOR]

The human microbiota impacts a variety of diseases and responses to therapeutics. Due to a lack of robust in vitro models, detailed mechanistic explanations of host‐microbiota interactions cannot often be recapitulated. We describe the design and development of a novel, versatile and modular in vitro system that enables indirect coculture of human epithelial cells with anaerobic bacteria for the characterization of host‐microbe secreted metabolite interactions. This system was designed to compartmentalize anaerobes and human cells in separate chambers conducive to each organism's requisite cell growth conditions. Using perfusion, fluidic mixing, and automated sample collection, the cells continuously received fresh media, while in contact with their corresponding compartments conditioned supernatant. Supernatants from each chamber were collected in a cell‐free time‐resolved fashion. The system sustained low oxygen conditions in the anaerobic chamber, while also supporting the growth of a representative anaerobe (Bacteroides thetaiotaomicron) and a human colonic epithelial cell line (Caco‐2) in the aerobic chamber. Caco‐2 global gene expression changes in response to coculture with B. thetaiotaomicron was characterized using RNA sequencing. Extensive, targeted metabolomics analysis of over 150 central carbon metabolites was performed on the serially collected supernatants. We observed broad metabolite changes in host‐microbe coculture, compared to respective mono‐culture controls. These effects were dependent both on sampling time and the compartment probed (apical vs. basolateral). Coculturing resulted in the depletion of several important metabolites, including guanine, uridine 5'‐monophosphate, asparagine, and thiamine. Additionally, while Caco‐2 cells cultured alone predominantly affected the basolateral metabolite milieu, increased abundance of 2,3‐dihydroxyisovalerate and thymine on the basolateral side, occurred when the cells were cocultured with B. thetaiotaomicron. Thus, our system can capture the dynamic, competitive and cooperative processes between host cells and gut microbes. [ABSTRACT FROM AUTHOR]

Purpose: To develop and evaluate a deep learning (DL) ‐based rapid image reconstruction and motion correction technique for high‐resolution Cartesian first‐pass myocardial perfusion imaging at 3T with whole‐heart coverage for both single‐slice (SS) and simultaneous multi‐slice (SMS) acquisitions. Methods: 3D physics‐driven unrolled network architectures were utilized for the reconstruction of high‐resolution Cartesian perfusion imaging. The SS and SMS multiband (MB) = 2 networks were trained from 135 slices from 20 subjects. Structural similarity index (SSIM), peak SNR (PSNR), and normalized RMS error (NRMSE) were assessed, and prospective images were blindly graded by two experienced cardiologists (5, excellent; 1, poor). For respiratory motion correction, a 2D U‐Net based motion corrected network was proposed, and the temporal fidelity and second‐order derivative were calculated to assess the performance of the motion correction. Results: Excellent performance was demonstrated in the proposed technique with high SSIM and PSNR, and low NRMSE. Image quality scores were (4.3 [4.3, 4.4], 4.5 [4.4, 4.6], 4.3 [4.3, 4.4], and 4.5 [4.3, 4.5]) for SS DL and SS L1‐SENSE, MB = 2 DL and MB = 2 SMS‐L1‐SENSE, respectively, showing no statistically significant difference (p > 0.05 for SS and SMS) between (SMS)‐L1‐SENSE and the proposed DL technique. The network inference time was around 4 s per dynamic perfusion series with 40 frames while the time of (SMS)‐L1‐SENSE with GPU acceleration was approximately 30 min. Conclusion: The proposed DL‐based image reconstruction and motion correction technique enabled rapid and high‐quality reconstruction for SS and SMS MB = 2 high‐resolution Cartesian first‐pass perfusion imaging at 3T. [ABSTRACT FROM AUTHOR]

Purpose: To propose the simulation‐based physics‐informed neural network for deconvolution of dynamic susceptibility contrast (DSC) MRI (SPINNED) as an alternative for more robust and accurate deconvolution compared to existing methods. Methods: The SPINNED method was developed by generating synthetic tissue residue functions and arterial input functions through mathematical simulations and by using them to create synthetic DSC MRI time series. The SPINNED model was trained using these simulated data to learn the underlying physical relation (deconvolution) between the DSC‐MRI time series and the arterial input functions. The accuracy and robustness of the proposed SPINNED method were assessed by comparing it with two common deconvolution methods in DSC MRI data analysis, circulant singular value decomposition, and Volterra singular value decomposition, using both simulation data and real patient data. Results: The proposed SPINNED method was more accurate than the conventional methods across all SNR levels and showed better robustness against noise in both simulation and real patient data. The SPINNED method also showed much faster processing speed than the conventional methods. Conclusion: These results support that the proposed SPINNED method can be a good alternative to the existing methods for resolving the deconvolution problem in DSC MRI. The proposed method does not require any separate ground‐truth measurement for training and offers additional benefits of quick processing time and coverage of diverse clinical scenarios. Consequently, it will contribute to more reliable, accurate, and rapid diagnoses in clinical applications compared with the previous methods including those based on supervised learning. [ABSTRACT FROM AUTHOR]

Background: Hospital-acquired pressure injuries (HAPIs) have a major impact on patient outcomes in intensive care units (ICUs). Effective prevention relies on early and accurate risk assessment. Traditional risk-assessment tools, such as the Braden Scale, often fail to capture ICU-specific factors, limiting their predictive accuracy. Although artificial intelligence models offer improved accuracy, their "black box" nature poses a barrier to clinical adoption. Objective: To develop an artificial intelligence–based HAPI risk-assessment model enhanced with an explainable artificial intelligence dashboard to improve interpretability at both the global and individual patient levels. Methods: An explainable artificial intelligence approach was used to analyze ICU patient data from the Medical Information Mart for Intensive Care. Predictor variables were restricted to the first 48 hours after ICU admission. Various machine-learning algorithms were evaluated, culminating in an ensemble "super learner" model. The model's performance was quantified using the area under the receiver operating characteristic curve through 5-fold cross-validation. An explainer dashboard was developed (using synthetic data for patient privacy), featuring interactive visualizations for in-depth model interpretation at the global and local levels. Results: The final sample comprised 28 395 patients with a 4.9% incidence of HAPIs. The ensemble super learner model performed well (area under curve = 0.80). The explainer dashboard provided global and patient-level interactive visualizations of model predictions, showing each variable's influence on the risk-assessment outcome. Conclusion: The model and its dashboard provide clinicians with a transparent, interpretable artificial intelligence–based risk-assessment system for HAPIs that may enable more effective and timely preventive interventions. [ABSTRACT FROM AUTHOR]

Due to the discrepancy between patients awaiting a heart transplant and the availability of donor hearts, strategies to expand the donor pool and improve the transplant's success are crucial. This review aims to summarize current knowledge on the ex vivo heart preservation (EVHP) experience as an alternative to standard cold static storage (CSS). EVHP techniques can improve the preservation of the donor's heart before transplantation and allow for pre-transplant organ evaluation. [ABSTRACT FROM AUTHOR]

Background Methods Results Conclusions Ex vivo perfusion of transplant‐declined human organs has emerged as a promising platform to study the response of an organ to novel therapeutic strategies. However, to fully realize the capability of this platform for performing translational research in human organ pathophysiology, there is a need for robust assays to assess organ function and disease. State‐of‐the‐art research methods rely on analyses of biopsies taken during perfusion, which both damages the organ and only provides localized information. Developing non‐invasive, whole organ methods of assessment is critical to the further development of this research platform.We use ex vivo cold infusion scanning (EXCIS) with contrast‐enhanced computed tomography (CT) to quantify perfusion in kidneys preserved ex vivo. EXCIS‐CT computes three complementary metrics for whole organ assessment: a dynamic assessment of contrast filling, a measure of vascular network anatomical structure, and a static assessment of perfusion heterogeneity.These metrics were applied to a series of six transplant‐declined human kidneys, which demonstrated a range of anatomies and perfusion. Lastly, two transplant‐declined human kidneys were imaged before and after a 1‐h period of ex vivo normothermic perfusion (NMP). We found variable responses to NMP, with one kidney maintaining the vascular network and hemodynamics and the other showing significant changes in vessel size and spatial perfusion profile.EXCIS‐CT provides metrics that can be used to characterize whole organ perfusion and vascular function. [ABSTRACT FROM AUTHOR]

Non-invasive perfusion imaging by Arterial spin labeling (ASL) can be advantageous at Ultra-high field (UHF) MRI, since the image SNR and the T1 relaxation time both increase with the static field. However, ASL implementation, especially at 7T, is not trivial. Especially for ASL, UHF MRI comes with many challenges, mainly due to B1+ inhomogeneities. This study aimed to investigate the effects of different transmit coil configurations on perfusion-weighted imaging at 7T using a flow-sensitive alternating inversion recovery (FAIR) technique with time-resolved frequency offset corrected inversion (TR-FOCI) pulses for labeling and background suppression. We conducted a performance comparison between a parallel transmit (pTx) system equipped with 32 receive (Rx) and 8 transmit (Tx) channels and a standard setup with 32Rx and 2Tx channels. Our findings demonstrate that the pTx system, characterized by a more homogeneous B1 transmit field, resulted in a significantly higher contrast-to-noise ratio, temporal signal-to-noise ratio, and lower coefficient of variance (CoV) than the standard 2Tx setup. Additionally, both setups demonstrated comparable capabilities for functional mapping of the hand region in the motor cortex, achieving reliable results within a short acquisition time of approximately 5 minutes. [ABSTRACT FROM AUTHOR]

Background: The indocyanine green (ICG) fluorescence test has become a standard test in surgical procedures, facilitating the assessment of blood perfusion in real-time. While its utility in emergency surgeries for evaluating anastomotic blood supply is well-established, its application in trauma cases, especially those involving mesenteric hematoma, remains underexplored. Herein, we present a case to illustrate the efficacy of the ICG fluorescence test in such scenarios. Case presentation: A 51-year-old man with uncontrolled hypertension suffered blunt abdominal trauma following a motor vehicle accident. We used the intra-operative ICG fluorescence test to chart the surgical plan for the patient. A combination of diagnostic laparoscopy with ICG fluorescence testing effectively excluded bowel ischemia, leading to the avoidance of intestinal resection and the need for a temporary ostomy. The patient resumed enteral nutrition. Conclusions: Our case underscores the efficacy of ICG fluorescence testing in assessing bowel viability and guiding surgical strategies in trauma patients with mesenteric hematoma. By facilitating real-time visualization of blood perfusion, ICG testing enables the adoption of conservative treatments in patients who would traditionally require more invasive surgical interventions, with minimal effect on operation time and cost. [ABSTRACT FROM AUTHOR]

Background Methods Results Conclusions Ex vivo machine perfusion (EVMP) has been established to extend viability of donor organs. However, EVMP protocols are inconsistent. We hypothesize that there is a significant relationship between specific parameters during EVMP and perfusion outcomes.A meta‐analysis of literature was conducted in accordance with the Preferred Reporting Items for Systematic Review and Meta‐Analysis (PRISMA) Statement. The search encompassed articles published before July 25, 2023. PubMed, Embase, and CENTRAL databases were screened using search terms “ex‐vivo,” “ex‐situ,” “machine,” and “perfusion.” Weight gain, an indicator of organ viability, was chosen to compare outcomes. Extracted variables included perfused organ, warm and cold ischemia time before perfusion, perfusion duration, perfusate flow, pressure, temperature, perfusate composition (presence of cellular or acellular oxygen carrier, colloids, and other supplements) and percent weight change. Data were analyzed using SPSS statistical software.Overall, 44 articles were included. Red blood cell‐based perfusates resulted in significantly lower weight gain compared to acellular perfusates without oxygen carriers (11.3% vs. 27.0%, p < 0.001). Hemoglobin‐based oxygen carriers resulted in significantly lower weight gain compared to acellular perfusates (16.5% vs. 27%, p = 0.006). Normothermic perfusion led to the least weight gain (14.6%), significantly different from hypothermic (24.3%) and subnormothermic (25.0%) conditions (p < 0.001), with no significant difference between hypothermic and subnormothermic groups (24.3% vs. 25.0%, p = 0.952). There was a positive correlation between flow rate and weight gain (ß = 13.1, R = 0.390, p < 0.001).Oxygen carriers, low flow rates, and normothermic perfusate temperature appear to improve outcomes in EVMP. These findings offer opportunities for improving organ transplantation outcomes. [ABSTRACT FROM AUTHOR]

Objective: Our study aimed to investigate the effects of different extracorporeal membrane oxygenation (ECMO) blood flow rates on lung perfusion assessment using the saline bolus-based electrical impedance tomography (EIT) technique in patients on veno-venous (VV) ECMO. Methods: In this single-centered prospective physiological study, patients on VV ECMO who met the ECMO weaning criteria were assessed for lung perfusion using saline bolus-based EIT at various ECMO blood flow rates (gradually decreased from 4.5 L/min to 3.5 L/min, 2.5 L/min, 1.5 L/min, and finally to 0 L/min). Lung perfusion distribution, dead space, shunt, ventilation/perfusion matching, and recirculation fraction at different flow rates were compared. Results: Fifteen patients were included. As the ECMO blood flow rate decreased from 4.5 L/min to 0 L/min, the recirculation fraction decreased significantly. The main EIT-based findings were as follows. (1) Median lung perfusion significantly increased in region-of-interest (ROI) 2 and the ventral region [38.21 (34.93–42.16)% to 41.29 (35.32–43.75)%, p = 0.003, and 48.86 (45.53–58.96)% to 54.12 (45.07–61.16)%, p = 0.037, respectively], whereas it significantly decreased in ROI 4 and the dorsal region [7.87 (5.42–9.78)% to 6.08 (5.27–9.34)%, p = 0.049, and 51.14 (41.04–54.47)% to 45.88 (38.84–54.93)%, p = 0.037, respectively]. (2) Dead space significantly decreased, and ventilation/perfusion matching significantly increased in both the ventral and global regions. (3) No significant variations were observed in regional and global shunt. Conclusions: During VV ECMO, the ECMO blood flow rate, closely linked to recirculation fraction, could affect the accuracy of lung perfusion assessment using hypertonic saline bolus-based EIT. [ABSTRACT FROM AUTHOR]

Background: Accurate assessment of therapy response to chemotherapy could possibly offer a bladder-sparing approach in selected patients with localized muscle-invasive bladder cancer (MIBC). The aim of this study was to evaluate whether [15O]H2O PET/MRI can be used for assessment of complete local pathological response to preoperative chemotherapy in patients with MIBC. Methods: This prospective pilot study included 13 patients with MIBC treated with neoadjuvant or induction chemotherapy and subsequent radical cystectomy. Patients underwent a [15O]H2O PET/MRI scan before chemotherapy and another scan after chemotherapy before radical cystectomy. Volumes of interest were delineated on T2-weighted MRI and transferred to parametric images for dynamic analysis. Tumor blood flow (TBF) was estimated by [15O]H2O PET. Changes in TBF were compared with histopathology. The Wilcoxon matched-pairs signed-ranks test was used for comparing pre- and post-chemotherapy measurements. Results: Mean TBF decreased by 49%. Mean TBF in complete responders (ypT0N0/ypTis) was not significantly different from non-complete responders (≥ypT1) (p = 0.52). Conclusions: Despite a measurable decrease in TBF after chemotherapy treatment, we were not able to estimate a TBF threshold for identifying complete responders to chemotherapy for MIBC patients. Further studies are needed to elucidate the potential of [15O]H2O PET/MRI in assessing therapy response in MIBC. [ABSTRACT FROM AUTHOR]

The Impella (Abiomed, Danvers, MA, USA) microaxial pump is a percutaneous mechanical circulatory support (MCS) that has been shown to increase coronary perfusion, reduce myocardial oxygen demand, and improve peripheral organ perfusion. Therefore, indications for the Impella device include emergency use for cardiogenic shock (CS) and pre-emptive implantation during high-risk percutaneous coronary intervention (HR-PCI). However, despite their exponential use in cardiovascular practice over the past decade, there is limited randomized evidence to support the benefits of this therapy and growing concern regarding complication rates. In this review, we summarize the principles, evidence, and practical considerations of the most widely used Impella CP percutaneous left ventricular support in both CS and HR-PCI settings, moving from the historical background to current issues and future expectations for this device. [ABSTRACT FROM AUTHOR]

Mutations of isocitrate dehydrogenase 1 (IDH1) are key biomarkers for glioma classification, but current methods for detection of mutated IDH1 (mIDH1) require invasive tissue sampling and cannot be used for longitudinal studies. Positron emission tomography (PET) imaging with mIDH1-selective radioligands is a promising alternative approach that could enable non-invasive assessment of the IDH status. In the present work, we developed efficient protocols for the preparation of four 18F-labeled derivatives of the mIDH1-selective inhibitor olutasidenib. All four probes were characterized by cellular uptake studies with U87 glioma cells harboring a heterozygous IDH1 mutation (U87-mIDH) and the corresponding wildtype cells (U87-WT). In addition, the most promising probe was evaluated by PET imaging in healthy mice and mice bearing subcutaneous U87-mIDH and U87-WT tumors. Although all four probes inhibited mIDH1 with variable potencies, only one of them ([18F]mIDH-138) showed significantly higher in vitro uptake into U87-mIDH compared to U87-WT cells. In addition, PET imaging with [18F]mIDH-138 in mice demonstrated good in vivo stability and low non-specific uptake of the probe, but also revealed significantly higher uptake into U87-WT compared to U87-mIDH tumors. Finally, application of a two-tissue compartment model (2TCM) to the PET data indicated that preferential tracer uptake into U87-WT tumors results from higher specific binding rather than from differences in tracer perfusion. In conclusion, these results corroborate recent findings that mIDH1-selective inhibition may not directly correlate with mIDH1-selective target engagement and indicate that in vivo engagement of wildtype and mutated IDH1 may be governed by factors that are not faithfully reproduced by in vitro assays, both of which could complicate development of PET probes. [ABSTRACT FROM AUTHOR]

The key goal in lung donation remains the improvement of graft preservation with the ultimate objective of increasing the number and quality of lung transplants (LTx). Therefore, in recent years the field of graft preservation focused on improving outcomes related to solid organ regeneration and restoration. In this contest Ex-Vivo Lung Perfusion (EVLP) plays a crucial role with the purpose to increase the donor pool availability transforming marginal and/or declined donor lungs suitable for transplantation. Aim of this proof of concept is to test the safety, suitability and feasibility of a new tilting dome for EVLP designed considering the dorsal lung areas as the "Achilles' heel" of the EVLP due to a more fluid accumulation than in the supine standard position. [ABSTRACT FROM AUTHOR]

Objective: Rare disease Background: Septic arthritis of the shoulder is a rare and challenging condition to treat. Typically, arthroscopic debridement is the common approach. Specifically, septic arthritis of the shoulder caused by methicillin-resistant bacteria is extremely difficult to cure due to persistent infection and limited antibiotic options. However, recent studies have demonstrated that continuous local antibiotic perfusion (CLAP) can provide favorable results for bone and soft tissue infections. By administering the antibiotics required to suppress the biofilm, CLAP can effectively treat the infection while sparing the tissue. Case Report: A 46-year-old woman undergoing long-term hemodialysis treatment for congenital anomalies of the kidney and urinary tract experienced severe pain in the left shoulder joint during glucocorticoid treatment for amyloid arthritis of the right shoulder. Despite the absence of fever, significant swelling and fluid accumulation were observed in the left shoulder joint, leading to the performance of a puncture. A bacterial examination of the puncture fluid detected methicillin-resistant coagulase-negative Staphylococcus epidermidis (MRCNS). In this report, we present a case in which CLAP was administered for septic arthritis of the shoulder caused by methicillin-resistant bacteria. After irrigation debridement, the patient received intravenous antibiotics and CLAP. Following the initiation of treatment, the dosage of antibiotics was adjusted while performing therapeutic drug monitoring. An early improvement in the inflammatory response and sedation of the infection was observed, with no relapse after 2 years. Conclusions: Septic arthritis can lead to serious functional impairment if left untreated. CLAP is a promising option for managing septic arthritis of the shoulder. [ABSTRACT FROM AUTHOR]

Background Methods Results Conclusion Ex vivo lung perfusion (EVLP) conducted outside of the transplant center has increased in recent years to mitigate its limitation by resources and expertise. We sought to evaluate EVLP performed at transplant centers and externally.Lung transplant recipients were identified from the United Network for Organ Sharing Database. Recipients were then stratified into two groups based where they were perfused: Transplant Program (TP) or External Perfusion Centers (EPC). The groups were assessed with comparative statistics and long‐term survival was assessed by Kaplan–Meier method. The groups were then 1:1 propensity and this process was repeated.EPC use was generally restricted to the Southern United States. Following matching, there were no significant differences in post‐operative outcomes to include post‐operative stroke, dialysis, airway dehiscence, ECMO use, ventilator use or incidence of primary graft dysfunction Grade 3. Adjusted 3‐year survival was 68.9% (95% Confidence Interval [CI]: 60.9%–77.9%) for the TP group and 67.6% (95% CI: 61.0%–74.9%) for the EPC group (p = 0.69). In allografts with extended ischemia (14+ h), those in the TP group had significantly longer length of stay, prolonged ventilation and treated rejection in the 1st year, though no significant difference in mid‐term survival (p = 0.66).EVLP performed at an EPC can be carried out with results and survival similar to allografts undergoing EVLP at a TP. EPCs will extend the valuable resource of EVLP to lung transplant programs without the resources to perform EVLP. [ABSTRACT FROM AUTHOR]

Background/Objectives: To analyze the best noninvasive tests prognosis marker in patients with diabetic foot ulcer (DFU) who underwent endovascular revascularization based on clinical outcomes, such as healing rate, time to heal, and free amputation survival after at least a six-month follow-up. Methods: A multicentric prospective observational study was performed with 28 participants with ischemic or neuroischemic DFU who came to the participant centers and underwent endovascular revascularization between January 2022 and March 2023. Toe systolic pressure (TP), ankle systolic pressure (AP), the ankle brachial pressure index (ABPI), the toe brachial pressure index (TBPI), transcutaneous pressure of oxygen (TcPO2), and skin perfusion pressure (SPP) were evaluated using PeriFlux 6000 System, Perimed, Sweden, before (Visit 0) and four weeks after revascularization (Visit 1). The primary clinical outcome was an evaluation of the clinical evolution of noninvasive tests comparing Visit 0 and Visit 1, estimating the sensitivity for predicting wound healing of noninvasive tests at six months following initial recruitment. Results: After six months, 71.43% (n = 20) of DFU healed, four patients (14.3%) received major amputations, and one (3.5%) died. The two tests that best predicted wound healing after revascularization according to the ROC curve were TcPO2 and TP with sensitivities of 0.89 and 0.70 for the cut-off points of 24 mmHg and 46 mmHg, respectively. Conclusions: TcPO2 and TP were the two tests that best predicted wound healing in patients who underwent endovascular revascularization. Clinicians should consider the importance of the evaluation of microcirculation in the healing prognosis of patients with diabetic foot ulcers. [ABSTRACT FROM AUTHOR]

Background: The clinical impact of patient selection using FLAIR vascular hyperintensity (FVH)-diffusion-weighted imaging (DWI) mismatch for endovascular thrombectomy (EVT) in patients who have been symptomatic for over 6 h remains unclear. Herein, a retrospective study was conducted to compare the inter-rater reliability and clinical outcomes of patients selected for thrombectomy based on FVH-DWI mismatch with perfusion. Methods: Patients with anterior-circulation large-vessel occlusion selected simultaneously with MRI and perfusion imaging in the late time window from a single-center retrospective study were categorized into EVT-applicable (FVHDWI mismatch on MRI or perfusion imaging meeting the DEFUSE3 standards) and EVT-inapplicable groups based on MRI and perfusion imaging. The primary outcome was the 90-day functional independence rate. Safety outcomes encompassed symptomatic intracranial hemorrhage and mortality in 90 days. We assessed the consistency of the two profiles and compared the differences in functional independence rates of EVT patients among the EVT-applicable groups determined by MRI and perfusion. Results: A total of 130 patients were enrolled, of which 114 were classified into the EVT-applicable group after triaging using MRI images. In this group, 96 patients underwent EVT, with 53 of them (55.2%) achieving functional independence. A total of 110 patients were divided into EVT-applicable group based on perfusion, among which 92 underwent EVT, with 49 of them (53.2%) achieving functional independence. The consistency of identifying EVT indication was moderate between two groups (κ = 0.42, 95% CI, 0.17-0.67). The functional independence rate was comparable between patients in the two EVT-applicable groups based on the two methods (55.2% vs. 53.2%, p = 0.789). Conclusion: MRI triaging based on FVH-DWI mismatch showed moderate interrater reliability compared with perfusion-based triage and comparable efficacy in predicting clinical outcomes after EVT. [ABSTRACT FROM AUTHOR]

Background: Schizophrenia is a prevalent psychiatric disorder that affects 1% of the global population. Schizophrenia frequently begins in late adolescence or early adulthood, causing significant educational, social, and economic costs for people and society. Functional neuroimaging research on schizophrenia physiopathology has been beneficial. Arterial spin labelling (ASL) is one of functional magnetic resonance imaging (fMRI) technologies that assess brain function without radiation. ASL uses magnetic resonance (MR) imaging to quantify tissue-level brain perfusion non-invasively. Arterial spin labelling (ASL) is one of the functional magnetic resonance imaging (fMRI) technologies that assess the brain function without radiation hazards. ASL uses magnetic resonance (MR) imaging to quantify tissue-level brain perfusion non-invasively. Many publications were performed on role of different advanced MRI techniques in schizophrenia, but our study insisted on the added value of combined ASL and MRS over the conventional MRI in schizophrenic Egyptian population sample. Aim of the work: The purpose of this work was to evaluate the added value of combined ASL-perfusion MRI and MRS in schizophrenic patients. Methods: This prospective case–control study was carried out on two groups: First group was 30 patients who were diagnosed clinically as schizophrenic patients, and second group was 20 healthy volunteers as a control group for comparison in the period from August 2021 till July 2022. Results: The majority of newly diagnosed cases had significant higher positive symptoms than chronic cases. According to arterial spin labelling (ASL) data, rCBF was noticed to be reduced in anterior cingulate, frontal lobe, and parietal lobe of both patients' subgroups but more significant in chronically ill patients. Convergent results of decreased rCBF were also found in the parietal lobe and occipital lobe. Magnetic resonance spectroscopic analysis showed that NAA was decreased in the anterior cingulate cortex, thalami and basal ganglia of the newly diagnosed cases more than chronic cases. The ASL-MRI perfusion accurately detected the hypo-perfusion of different brain regions with sensitivity 100%, specificity 66.67%, positive predictive value 96.43%, negative predictive value 100%, and accuracy 96.67%, while MR spectroscopy showed sensitivity 100%, specificity 33.33%, positive predictive value 93.10%, negative predictive value 100%, and accuracy 93.33% in evaluation of changes of brain metabolites. Conclusion: ASL is a promising functional MRI technique that can produce together with MRS quantitative information about the metabolites of different brain regions. The ASL-MRI appears as a reliable non-invasive technique to measure cerebral blood flow and identify decreased rCBF without any contrast administration, and it could be repeatable which helps in early diagnosis as well as follow-up of the progression of the disease. [ABSTRACT FROM AUTHOR]

Purpose: Compartment syndrome remains difficult to diagnose early in its clinical course. Pressure transducer catheters have been used to directly measure intracompartmental pressure (ICP), but this method is unreliable, with a false positive rate of 35%. We have previously used intramuscular near infrared spectroscopy to detect changes in tissue oxygen saturation (StO2) in response to increasing ICP using a novel implantable probe. However, measuring StO2 may not be sufficient to identify CS in the clinical setting. The pathophysiology of CS consists of increased ICP, leading to decreased tissue perfusion, and resulting in reduced tissue oxygenation. More clinically useful information may come from the integration of multiple data streams to aid in the diagnosis of CS. In this study, we present a novel, intramuscular probe capable of simultaneous measurement of ICP, StO2, and microvascular blood flow in a porcine model of ACS. Methods: Proof of concept for this device is demonstrated in a porcine lower extremity balloon compression model of ACS. Pressure was maintained for 20 min (short-term) or 3 h (long-term) before the balloon volume was removed. Results: In both short- and long-term experiments, as ICP increased with increasing balloon volume, the novel multimodal sensor simultaneously and reliably detected pressure elevation and corresponding reversible reductions in microvascular flow rate and tissue oxygenation. Conclusion: This novel trimodal device simultaneously measured the elevated ICP, decreased perfusion, and tissue ischemia of evolving ACS, substantiating our basic understanding of CS pathophysiology. [ABSTRACT FROM AUTHOR]

OBJECTIVES The objective of this study was to enhance the efficiency of aortic arch replacement through the development of a novel frozen elephant trunk (FET) prosthesis with an endovascular side branch for left subclavian artery (LSA) connection. After successful pre-clinical testing, the feasibility and safety of implementing this innovative prosthesis in human subjects were investigated. METHODS Between September 2020 and September 2021, 4 patients (mean age 67) with conditions such as penetrating ulcer, non A–non B aortic dissection and chronic arch aneurysm underwent surgery utilizing the customized device. Surgeries were performed under high moderate hypothermia (27°C), employing bilateral selective antegrade cerebral perfusion (SACP) and distal aortic perfusion. Anastomosis of the FET prosthesis with the aortic arch occurred in zone 1, followed by separate reimplantation of the left common carotid artery and the brachiocephalic artery. RESULTS All patients were discharged in good clinical condition. The mean aortic cross-clamp, antegrade selective cerebral perfusion and distal aortic perfusion times were 111, 71 and 31 min, respectively. Endovascular extension of the side branch for the LSA was required in all cases to prevent endoleak formation. One patient received a stent graft extension at the end of the operation, while 2 others underwent the procedure during their hospital stay. One patient was diagnosed with an endoleak at the first follow-up after 3 months, and endoleak sealing was achieved via the brachial artery with an extension stent graft. CONCLUSIONS Preliminary clinical outcomes suggest that the newly designed FET prosthesis shows promise in simplifying total arch replacement. These initial findings provide a foundation for planned clinical studies to further assess the effectiveness of this modified surgical hybrid graft, with particular attention to the length and diameter of the LSA sidearm. [ABSTRACT FROM AUTHOR]

Background: Due to insufficient near‐field resolution and artifacts, it is challenging to evaluate the left ventricular apical perfusion with phased‐array probes. By combining high‐frequency linear probe and contrast‐enhanced ultrasound (CEUS), imaging of apical myocardial perfusion could be improved. The study aims to evaluate the preliminary application of CEUS by high‐frequency linear probes to assess the apical perfusion. Methods: The study enrolled retrospectively 91 patients to test the feasibility of the novel method. In protocol 1, patients were stratified into a group with left anterior descending artery (LAD) stenosis (N = 40) and a group without LAD stenosis or coronary artery disease (N = 41) based on the degree of coronary artery narrowing, quantified by >50% stenosis in coronary angiography. Receiver operating characteristics (ROC) analysis was performed to test the diagnostic value of perfusion parameters. In protocol 2, the reproducibility of high‐frequency linear probe in apical perfusion analysis was compared with the conventional phased‐array probe in 30 patients. Results: (1) The novel method is feasible in 81(89.01%) patients. (2) In protocol 1, to detect LAD stenosis, the best cut‐off of β, T, A, and MBF were 10.32, 3.28, 9.39, and 4.99, respectively. Area under the curve of β, T, A, and MBF were.880,.881,.761, and.880, respectively. (3) In protocol 2, compared with phased‐array probe, the quantitative analysis of high‐frequency linear probe is of high reproducibility and could get good curve fitting (R2 =.29 vs. R2 =.71, P <.01). Conclusion: Observation of apical perfusion using this method is feasible and quantitative analysis allows an accurate and convenient identification of LAD stenosis. This method provides an alternative for patients who have difficulties in visualizing the apical region with a phased‐array probe. [ABSTRACT FROM AUTHOR]

Purpose: The Alberta Stroke Program Early CT Score (ASPECTS) is regularly used to guide patient selection for mechanical thrombectomy (MT). Similarly, penumbral imaging based on computed tomography perfusion (CTP) may serve as neuroimaging tool to guide treatment. Yet, patients with a large ischemic core on CTP may show only minor ischemic changes resulting in a high ASPECTS. Aim: We hypothesized twofold: (1) the treatment effect of vessel recanalization in patients with core volume > 50 mL but ASPECTS ⩾ 6 is not different compared to high ASPECTS patients with core volume < 50 mL, and (2) recanalization is associated with core overestimation. Methods: We conducted an observational study analyzing ischemic stroke patients consecutively treated with MT after triage by multimodal CT. Functional endpoint was the rate of functional independence at Day 90 defined as modified Rankin Scale (mRS) 0–2. Imaging endpoint was core overestimation, which was considered when CTP-derived core was larger than the final infarct volume assessed on follow-up imaging. Recanalization was evaluated with the extended Thrombolysis in Cerebral Infarction (eTICI) scale. Multivariable logistic regression analysis and propensity score matching (PSM) were used to assess the association of recanalization (eTICI ⩾ 2b) with functional outcome and core overestimation. Results: Of 630 patients with ASPECTS ⩾ 6, 91 patients (14.4%) had a large ischemic core. Following 1:1 PSM, the treatment effect of recanalization was not different in patients with large core and ASPECTS ⩾ 6 (+ 25.8%, 95% CI: 16.3–35.4, p < 0.001) compared to patients with ASPECTS ⩾ 6 and core volume < 50 mL (+ 14.9%, 95% CI: 5.7–24.1, p = 0.002). Recanalization (aOR: 3.46, 95% CI: 1.85–6.47, p < 0.001) and higher core volume (aOR: 1.03, 95% CI: 1.02–1.04, p < 0.001) were significantly associated with core overestimation. Conclusion: In patients with ASPECTS ⩾ 6, core volumes did not significantly modify outcomes following recanalization. Reperfusion and higher core volume were significantly associated with core overestimation which may explain the treatment effect of MT for patients with a large ischemic core but minor ischemic changes on non-enhanced CT. Data access statement: The data analyzed in this study will be available and shared on reasonable request from any qualified researcher for the purpose of replicating the results after clearance by the local ethics committee. [ABSTRACT FROM AUTHOR]

To determine the role of near-infrared fluorescence imaging (NIFI) combined with indocyanine green (ICG) to assess ureteral tissue perfusion in a benign genitourinary reconstruction cohort with a high prevalence of prior abdominopelvic radiation and surgery. A prospective, single-surgeon series, between June 2018 and April 2022, of patients who underwent open genitourinary reconstructive surgeries in which NIFI/ICG was utilized to intraoperatively assess ureteral tissue perfusion prior to ureteral anastomosis. Primary outcome was ureteroanastomotic stricture (UAS). Secondary outcomes included impact of NIFI/ICG on surgical decision-making and ureter resection length. Thirty nine patients, median age 66, underwent 40 multimodality reconstructive surgeries during which NIFI/ICG was utilized in the open setting. Radiation-induced etiology was present in 32 of 40 (80%) patients. UAS occurred in 1 of 57 (1.8%) anastomoses with median follow-up of 23.4 months. Use of NIFI/ICG changed intraoperative decision-making in 63% of cases. Change in intraoperative decision-making was more common in patients with prior abdominopelvic radiation (66%) compared to non-radiated patients (13%), P =.007. Discordance between subjective (white-light) and objective (NIFI/ICG) ureteral perfusion (white-light) occurred in 61% of ureters. Mean length of resected ureter was higher following objective assessment with NIFI/ICG (3.6 cm) versus subjective assessment (white light) conditions (1.8 cm), P =.001. Use of NIFI/ICG was associated with low rates of UAS at 2-year follow-up in a cohort with high prevalence of prior radiation. NIFI/ICG was associated with longer lengths of ureter resection and ureteral perfusion assessment discordance compared to subjective surgeon assessment under white-light conditions. [ABSTRACT FROM AUTHOR]

Background: Microvascular scarring compromises the functionality of the endometrium, and vascular flow at the junctional zone (JZ) may be the key to understanding poor reproductive outcomes in women with Asherman syndrome (AS). Aims: To investigate whether vascular perfusion of the uterus, measured by dynamic contrast‐enhanced magnetic resonance imaging (DCE‐MRI) is impaired in women with intrauterine adhesions (IUA) and AS. Materials and Methods: A prospective observational cohort pilot study of 23 women with IUA treated with hysteroscopic synecholysis and a control group of two patients with cervix cancer were subject to DCE‐MRI with gadolinium to assess uterine vascularity. Twelve regions of interest (ROIs) were allocated on the DCE‐MRI image incorporating the JZ, with control ROI placed at the psoas muscle. Individual ROIs were compared to the mean total perfusion (TP) in the same uterus. Pre‐ and post‐operative perfusion analyses were performed on five women. Receiver operator curves (ROC) were used to analyse MRI as a predictor of IUA. Results: There was no significant difference in perfusion; a trend toward reduced perfusion was observed in women with IUA compared to the controls. The ROC was predictive of higher‐grade and inoperable IUA. Conclusions: Reduced perfusion on DCE‐MRI as assessed by ROC predicted higher‐stage AS. The results of this study support further investigation of DCE‐MRI as a prognostic tool for AS prior to surgical intervention to assist in providing prognostic guidance for women suffering from AS. [ABSTRACT FROM AUTHOR]

The prone position is an immediately available and easily implemented procedure that was introduced more than 50 years ago as a method for improvement of gas exchange in patients with acute respiratory distress syndrome (ARDS). In the meantime, a survival advantage could also be shown in patients with severe ARDS, which led to the recommendation of the prone position for treatment of severe ARDS by expert consensus and specialist society guidelines. The continuing coronavirus disease 2019 (COVID-19) pandemic moved the prone position to the forefront of medicine, including the widespread implementation of the prone position for awake, spontaneously breathing nonintubated patients with acute hypoxemic respiratory insufficiency. The survival advantage is possible due to a reduction of the ventilator-associated lung damage. In this article, the physiological effects, data on clinical results, practical considerations and open questions with respect to the prone position are discussed. [ABSTRACT FROM AUTHOR]