Protocol description and initial experience in kidney graft perfusion using infrared thermography.

PURPOSE: Protocol description for renal perfusion study using thermographic technology and description of the thermographic and clinical behavior of the transplanted kidneys before and after unclamping. METHODS: Infrared thermographic images of renal grafts are obtained before kidney reperfusion, 10 min after and just before closing the surgical wound. Thermographic data is evaluated together with the type of graft and donor, cold ischemia time, hypovascularized areas determined by the surgeon during surgical intervention, alterations in vascular flow in postoperative echo-Doppler, time at the beginning of graft function and serum creatinine monitoring during postoperative follow-up. RESULTS: 17 grafts were studied. The mean temperature of the grafts before reperfusion, 10 min after and at the end of the surgery were 18.7 °C (SD 6.27), 32.36 °C (SD1.47) and 32.07 °C (SD1.78) respectively. 4 grafts presented hypoperfused areas after reperfusion. These areas presented a lower temperature compared to the well perfused parenchyma surface using thermographic images. CONCLUSION: The study of the usefulness and applicability of thermography can allow the development of tools that provide additional objective information on organ perfusion in real time and non-invasive manner. Our protocol and initial results can contribute to provide new evidence. Further analyses should be developed to shed light on the role of this technology.

Establishing a Critical Limb Ischemia Outpatient Center: Separating Facts from Myth.

Critical Limb Ischemia or chronic limb-threatening ischemia represents the end stage of peripheral artery disease where arterial flow is compromised to the lower extremities and risk of limb loss may become imminent. Revascularization of lower extremities is one of the cornerstones of limb salvage and amputation prevention. Establishing centers of high quality CLI therapy requires creating different foundational pillars in order to be successful. This article discusses critical limb ischemia center creation from the perspective of critical limb ischemia therapists working in an outpatient setting.

Pia-FLOW: Deciphering hemodynamic maps of the pial vascular connectome and its response to arterial occlusion.

The pial vasculature is the sole source of blood supply to the neocortex. The brain is contained within the skull, a vascularized bone marrow with a unique anatomical connection to the brain meninges. Recent developments in tissue clearing have enabled detailed mapping of the entire pial and calvarial vasculature. However, what are the absolute flow rate values of those vascular networks? This information cannot accurately be retrieved with the commonly used bioimaging methods. Here, we introduce Pia-FLOW, a unique approach based on large-scale transcranial fluorescence localization microscopy, to attain hemodynamic imaging of the whole murine pial and calvarial vasculature at frame rates up to 1,000 Hz and spatial resolution reaching 5.4 µm. Using Pia-FLOW, we provide detailed maps of flow velocity, direction, and vascular diameters which can serve as ground-truth data for further studies, advancing our understanding of brain fluid dynamics. Furthermore, Pia-FLOW revealed that the pial vascular network functions as one unit for robust allocation of blood after stroke.

Vascular changes of the peripapillary choroidal area in the thyroid orbitopathy.

PURPOSE: The aim of this study was to investigate the peripapillary choroidal vascular changes in thyroid orbitopathy (TO). METHODS: The study included 20 eyes of 10 patients with active TO (aTO), 30 eyes of 15 patients with inactive TO (inaTO) and 30 eyes of 30 healthy subjects. The peripapillary choroidal vascular change was assessed with peripapillary choroidal vascular index (pCVI), peripapillary choroidal luminal area (pLA), peripapillary choroidal stromal area (pSA), peripapillary total choroidal area (pTCA). RESULTS: Compared to the control group, there was a reduction in the nasal and temporal areas of pCVI in both the aTO and inaTO groups (aTO vs control: nasal p = 0.001 and temporal p = 0.004; inaTO vs control: nasal p = 0.007 and temporal p < 0.001), while the inferior area was lower only in the inaTO group (p = 0.001). Compared to the other groups, the inaTO group exhibited a decrease pSA (vs aTO: total p = 0.004, inferior p = 0.02 and vs control: total p = 0.01, inferior p = 0.03), pLA (vs aTO: total p = 0.02, inferior p = 0.02, temporal p < 0.001 and vs control: total p = 0.002, inferior p < 0.001, temporal p < 0.001) and pTCA (vs aTO: total p = 0.009, inferior p = 0.01, temporal p < 0.001 and vs control: total p = 0.003, inferior p = 0.001, temporal p < 0.001). CONCLUSION: The horizontal area (nasal and temporal area) of the peripapillary choroidal vascular structure may be more sensitive than the vertical area in TO patients. The first affected quadrant of RPC-VD in the active TO may be the inferior quadrant. Structural or vascular choroidal changes may occur during the chronic or post-active phase of the disease.

Giant splenic artery pseudoaneurysm with arteriovenous fistula: diagnostic challenges and interdisciplinary treatment considerations.

We present a compelling case of an elderly male with a complex medical history who presented with sepsis secondary to a urinary tract infection. During admission, changes in his abdominal exam prompted imaging studies, which revealed a grade IV splenic laceration with a giant splenic artery pseudoaneurysm containing a suspected arteriovenous fistula component. Multidisciplinary discussion was had regarding patient management which resulted in the decision to perform an emergent splenectomy. Learning points from this case underscore the crucial role of interdisciplinary collaboration in the treatment of this pathology. Additionally, we discuss the decision-making process to support surgical intervention in the absence of clear guidelines in this exceedingly rare condition.

Comparison of Adaptations in the Gastrocnemius Muscle from an Exercise Program with and without Low-Intensity Blood Flow Restriction Banding in 18 Male Amateur Basketball Players Aged 16-45 Years.

BACKGROUND Basketball is a sport with a global impact and recognized major leagues, and is one of the most studied and analyzed sports for improvement at the level of the high-performance athlete. Increasing the jump height of basketball players is an essential factor for high athletic performance. MATERIAL AND METHODS This study aimed to identify the effect of low-intensity training with flow restriction versus the eccentric exercise protocol on amateur athletes. Eighteen amateur basketball players aged 16-45 years were divided into 2 groups: Group A consisted of 9 participants with low-intensity training with flow restriction (40% intensity) with 200 mmHg occlusion applying flow restriction bands in the popliteal area, while Group B consisted of 9 participants who performed an eccentric exercises protocol on the gastrocnemius. An anthropometric evaluation was applied, which consisted of perception of effort, range of movement (ROM), muscle strength intensity, and the power of the jump measured with a jump platform. RESULTS Notable changes were observed in favor of Group A for the right dorsiflexion, with mean difference (MD)=-2.444 (P=0.018); left dorsiflexion with MD=-2.778 (P=0.027) and left foot perimeter variable with MD=-0.667 (P=0.026) at 95% confidence interval (CI); while the vertical jump was in favor of Group B, with MD=-2.899 (P=0.006). CONCLUSIONS Low-intensity training with flow restriction and eccentric exercise protocol were both effective in improving jumping performance. A significant improvement was shown in the jump height and ROM of the 2 study groups.

Changes in the outer nuclear layer and choroidal vascularity during the manifest and quiescent phases of acute central serous chorioretinopathy.

To investigate alteration of outer nuclear layer (ONL) and choroidal vascularity index (CVI) in different status of central serous chorioretinopathy (CSC). A retrospective review of 65 CSC eyes with subretinal fluid (manifest CSC) and 40 control eyes was conducted in a single tertiary university hospital. Differences in best-corrected visual acuity (BCVA), ONL, and CVI were compared. CVI was assessed both in the entire choroid (CVI-EC) and around the 1500 µm leakage area (CVI-1500). Measurements were repeated after the subretinal fluid resorption (quiescent CSC), and compared. CSC eyes showed worse BCVA, thinner ONL and greater CVI than controls. Quiescent CSC showed a recovery of ONL compared to the manifest CSC, along with the BCVA improvement. The resolution of the CSC revealed a decrease across all three choroidal areas (total, stromal and luminal), with a more pronounced reduction in the stromal than in the luminal choroidal area, leading to an increase in the CVI. This phenomenon was shown in both CVI-EC and CVI-1500. Conclusively, ONL thickness can be used as a quantitative biomarker for photoreceptor function in CSC. Increased CVI may reflect a disease activity. The stromal choroidal area is particularly sensitive in illustrating leakage from the choroidal vasculature.

Quantitative assessment of colour fundus photography in hyperopia children based on artificial intelligence.

OBJECTIVES: This study aimed to quantitatively evaluate optic nerve head and retinal vascular parameters in children with hyperopia in relation to age and spherical equivalent refraction (SER) using artificial intelligence (AI)-based analysis of colour fundus photographs (CFP). METHODS AND ANALYSIS: This cross-sectional study included 324 children with hyperopia aged 3-12 years. Participants were divided into low hyperopia (SER+0.5 D to+2.0 D) and moderate-to-high hyperopia (SER≥+2.0 D) groups. Fundus parameters, such as optic disc area and mean vessel diameter, were automatically and quantitatively detected using AI. Significant variables (p<0.05) in the univariate analysis were included in a stepwise multiple linear regression. RESULTS: Overall, 324 children were included, 172 with low and 152 with moderate-to-high hyperopia. The median optic disc area and vessel diameter were 1.42 mm2 and 65.09 µm, respectively. Children with high hyperopia had larger superior neuroretinal rim (NRR) width and larger vessel diameter than those with low and moderate hyperopia. In the univariate analysis, axial length was significantly associated with smaller superior NRR width (ß=-3.030, p<0.001), smaller temporal NRR width (ß=-1.469, p=0.020) and smaller vessel diameter (ß=-0.076, p<0.001). A mild inverse correlation was observed between the optic disc area and vertical disc diameter with age. CONCLUSION: AI-based CFP analysis showed that children with high hyperopia had larger mean vessel diameter but smaller vertical cup-to-disc ratio than those with low hyperopia. This suggests that AI can provide quantitative data on fundus parameters in children with hyperopia.

Plasma and Tissue Amikacin Concentrations Following Regional Limb Perfusion of Chickens (Gallus gallus domesticus).

Intravenous regional limb perfusion (IVRLP) has been used in the treatment of pododermatitis and distal limb infections, which are significant causes of morbidity in avian species. This intravenous drug administration technique is designed to achieve high drug tissue concentrations while minimizing systemic toxic effects. Amikacin is commonly used for IVRLP in veterinary medicine, but dosing guidelines have not been established for its use in birds. The current study aimed to determine the tissue concentration of amikacin after a single IVRLP administration in healthy, euhydrated leghorn hen chickens (Gallus gallus domesticus). Chickens received a single IVRLP dose of 10 mg/kg amikacin and were euthanatized posttreatment at 1 hour (n = 6), 12 hours (n = 6), and 24 hours (n = 6) to assess tissue and synovial fluid concentrations of amikacin in the injected leg. Mean tissue concentrations were highest 1 hour post-IVRLP (synovial fluid = 153.0 µg/mL, metatarsal pad tissue = 26.05 µg/mL) before declining at the 12- and 24-hour time points. This indicates that administration of amikacin via IVRLP can reach minimum inhibitory concentrations of common bacterial isolates in tissues after a single treatment with 10 mg/kg amikacin. Regional limb perfusion every 24 hours is recommended, although the minimum days of treatment may be case dependent and vary based on response to therapy.

Erratum: Murine Left Pulmonary Hilar Clamp Model of Lung Ischemia Reperfusion Injury.

This corrects the article 10.3791/66232.

Single-staged revascularization and reconstruction after crush injury of the wrist and distal forearm: A protocolized approach.

BACKGROUND: Amputation of the wrist or distal forearm after high-energy trauma due to a crushing mechanism is associated with complex tissue defects, making repair, and reconstruction challenging. Given the difficulty of this type of salvage, patients unfortunately experience a high revision amputation rate. However, a higher quality of life has been reported in patients with successful reconstructions. Herein, we described a protocolized approach for revascularization and reconstruction for functional hand salvage after traumatic amputation from a crushing mechanism using an anterolateral thigh flap (ALT). METHODS: A retrospective review was performed between October 2016 and October 2023 for all patients who underwent single-stage emergent debridement, revascularization, and soft tissue coverage using the ALT after amputation at the level of the wrist or distal forearm secondary to high-energy crush injury. Charts were reviewed for the preoperative Mangled Extremity Salvage Score, intraoperative details including what structures were injured and the reconstructive method performed, and postoperative data such as follow-up duration, outcomes, and complications. RESULTS: Eleven patients met the inclusion criteria with an average age of 35.5 (21-49) years old. The average size of the skin soft tissue defects was 17.3 × 8 cm (range, length: 13-25 cm, width: 6-13 cm), and all cases had associated injury to the underlying bone, nerves, and blood vessels. The average size of the ALT flap used for reconstruction was 19.2 × 9.8 cm (range, length: 14-27 cm, width: 7-15 cm). All patients had survival of the replanted limb. One patient experienced partial flap necrosis that required secondary debridement and skin graft. Nine patients healed without requiring any additional debridement procedures. Patient follow-up averaged 24.6 (12-38) months. All patients achieved satisfactory functional recovery with Grade II to III of Chen's criteria. CONCLUSIONS: For patients with traumatic crush amputation to the wrist with surrounding soft tissue injury, thorough debridement, revascularization, and reconstruction of amputated limbs can be performed in a single stage using the ALT. A protocolized approach from two institutions is presented, demonstrating improved survival and reduced complications of the traumatized limb with improved long-term patient outcomes.

New Insights into Hepatic and Intestinal Microcirculation and Pulmonary Inflammation in a Model of Septic Shock and Veno-Arterial Extracorporeal Membrane Oxygenation in the Rat.

Despite significant efforts toward improving therapy for septic shock, mortality remains high. Applying veno-arterial (V-A) extracorporeal membrane oxygenation (ECMO) in this context remains controversial. Since the cannulation of the femoral artery for V-A ECMO return leads to lower body hyperoxia, this study investigated the impact of V-A ECMO therapy on the intestinal and hepatic microcirculation during septic shock in a rodent model. Thirty male Lewis rats were randomly assigned to receive V-A ECMO therapy with low (60 mL/kg/min) or high (90 mL/kg/min) blood flow or a sham procedure. Hemodynamic data were collected through a pressure-volume catheter in the left ventricle and a catheter in the lateral tail artery. Septic shock was induced by intravenous administration of lipopolysaccharide (1 mg/kg). The rats received lung-protective ventilation during V-A ECMO therapy. The hepatic and intestinal microcirculation was measured by micro-lightguide spectrophotometry after median laparotomy for two hours. Systemic and pulmonary inflammation was detected via enzyme-linked immunosorbent assays (ELISA) of the plasma and bronchoalveolar lavage (BAL), respectively, measuring tumor necrosis factor-alpha (TNF-α), interleukins 6 (IL-6) and 10 (IL-10), and C-X-C motif ligands 2 (CXCL2) and 5 (CXCL5). Oxygen saturation and relative hemoglobin concentration were reduced in the hepatic and intestinal microcirculation during V-A ECMO therapy, independent of the blood flow rate. Further, rats treated with V-A ECMO therapy also presented elevated systolic, diastolic, and mean arterial blood pressure and increased stroke volume, cardiac output, and left ventricular end-diastolic volume. However, left ventricular end-diastolic pressure was only elevated during high-flow V-A ECMO therapy. Blood gas analysis revealed a dilutional anemia during V-A ECMO therapy. ELISA analysis showed an elevated plasma CXCL2 concentration only during high-flow V-A ECMO therapy and elevated BAL CXCL2 and CXCL5 concentrations only during low-flow V-A ECMO therapy. Rats undergoing V-A ECMO therapy exhibited impaired microcirculation of the intestine and liver during septic shock despite increased blood pressure and cardiac output. Increased pulmonary inflammation was detected only during low-flow V-A ECMO therapy in septic shock.

Applications of SPECT and PET Imaging for the Physiological Evaluation of Lower Extremity Peripheral Artery Disease.

Peripheral artery disease (PAD) is classified as the narrowing or complete occlusion of the lower extremity arteries due to atherosclerosis. The risk of developing PAD increases with increased age and risk factors such as smoking, diabetes, hypertension, and hypercholesterolemia. Current treatment for PAD involves lifestyle and symptom management, statin and antiplatelet therapy, and/or surgical interventions to improve quality of life with varying efficacy. PAD affects approximately 5 to 6 percent of the global population, with this global burden continuing to increase. Despite the increase in disease prevalence, no gold standard functional diagnostic tool has been established for enabling early detection of the disease, appropriate medical management, and prediction of adverse outcomes for PAD patients. The visualization and quantification of the physiological consequences of PAD are possible by way of nuclear imaging: specifically, via scintigraphy, single-photon emission computed tomography (SPECT), and positron emission tomography (PET) imaging. These non-invasive modalities, when combined with targeted radionuclides, possess utility for detecting functional perfusion deficits and provide unique insight into muscle tissue- and vascular-level characteristics of PAD patients. This review discusses the past, present, and emerging applications of hybrid nuclear imaging modalities in the evaluation and monitoring of patients with PAD.

Uterine tone: A neglected criterion for the selection of bovine embryo transfer recipients.

This study evaluated the relationship between CL features assessed by ultrasound (luteal tissue area and blood flow, BF) or rectal palpation (size), uterine tone (UT), plasma progesterone (P4) concentration on Day 7 (D7) and subsequent pregnancy outcomes in bovine embryo recipients. A total of 163 cows and heifers were included in this study. The expected day of ovulation after the synchronization protocol was designated as D0. On D7, ovaries and uterus were examined by ultrasonography and rectal palpation, and subjective scores (1-3 scale) were assigned for CL size, area and BF, and for UT. Blood samples were collected for further P4 analysis. Each embryo recipient then received a grade I frozen-thawed in vivo-produced blastocyst, which was transferred to the uterine horn ipsilateral to the CL. Pregnancy diagnosis was performed on D35, and the results were retrospectively compared with the assigned scores for CL and UT. We observed a significant (p < .02) interaction between CL size and UT, with a progressive increase in the likelihood of pregnancy for recipients bearing a large CL among those with turgid UT. Ultrasound scoring of the CL using B-mode and Doppler-mode did not significantly predict pregnancy rates on D35 (p < .6 and p < .5, respectively). However, logistic regression analysis revealed a trend towards a quadratic effect (p < .08 and p < .06) indicating that the probability of pregnancy varied according to the area of luteal tissue and P4 concentrations, respectively. No significant (p > .05) association was found between the probability of pregnancy and the BF area of the CL. In summary, UT before embryo transfer may reflect successful recipient synchronization. Elevated P4 levels, assessed by CL size, may offset uterine contractility, mitigating adverse effects. Additionally, the CL area may be more important than its vascularization area when evaluating recipients D7 after ovulation.

Pathological Changes in the Gastrocnemius Muscle throughout Hind Limb Ischemia Modeling in Rats.

We present a two-stage model for the study of chronic hind limb ischemia in rats. In the area of ischemia, sclerotic changes with atrophic rhabdomyocytes and reduced vascularization were revealed. CD31 expression in the endothelium increased proportionally to the number of vessels in the ischemic zone, and at the same time, focal expression of ßIII-tubulin was detected in the newly formed nerve fibers. These histological features are equivalent to the development of peripheral arterial disease in humans, which allows using our model in the search for new therapeutic strategies.

Progressive Choriocapillaris Changes on Optical Coherence Tomography Angiography Correlate With Stage Progression in AMD.

Purpose: We investigated the association between inner choroid flow deficit percentage (IC-FD%) using swept-source optical coherence tomography angiography (SS-OCTA) and progression of AMD. Methods: Retrospective, observational study including 64 eyes (42 participants) with early or intermediate AMD at baseline. Participants had two or more consecutive swept-source optical coherence tomography angiography covering a period of at least 18 months. Demographics, visual acuity, and AMD staging based on Beckman classification were reviewed. OCT was analyzed for hyperreflective foci, subretinal drusenoid deposits, hyporeflective drusen cores, and subfoveal choroidal thickness. IC-FD% was measured within the central 3- and 6-mm using a 16-µm slab, after compensation and binarization (Phansalkar method). Mixed-effects Cox regression models assessed the association between imaging biomarkers and AMD progression. Results: During follow-up (37 ± 9 months), 4 eyes with early AMD (31%) progressed to intermediate AMD and 30 (59%) eyes with intermediate AMD developed late AMD (19 geographic atrophy; 11 wet AMD). Baseline hyporeflective drusen core was associated with geographic atrophy development (P < 0.01), whereas greater IC-FD% (3-mm) was associated with wet AMD (P = 0.03). Time-varying analysis showed that faster subfoveal choroidal thickness reduction and IC-FD% (6-mm) increase were associated with geographic atrophy onset (P < 0.05), whereas IC-FD% (3-mm) increase was associated with wet AMD (P = 0.03). Notably, greater IC-FD% increases in the 3 mm (area under the curve = 0.72) and 6 mm (area under the curve = 0.89) were better predictive of wet AMD and geographic atrophy development, respectively. Conclusions: Our longitudinal IC-FD% assessment emphasizes the role of progressive choriocapillaris changes as a biomarker for AMD progression. Our findings support that widespread choriocapillaris alterations (6 mm) may precede progression to geographic atrophy, whereas more central choriocapillaris loss (3 mm) may provide an ischemic stimulus for wet AMD.

Establishment of an in vitro choroid complex system for vascular response screening.

The choroid, a vascularized tissue situated between the retina and the sclera, plays a crucial role in maintaining ocular homeostasis. Despite its significance, research on choroidal abnormalities and the establishment of effective in vitro models have been limited. In this study, we developed an in vitro choroid model through the co-culture of human induced pluripotent stem cells (hiPSC)-derived endothelial cells (ECs) and mouse choroidal fibroblasts (msCFs) with hiPSC-derived retinal pigment epithelial (RPE) cells via a permeable membrane. This model, inclusive of ECs, CFs, and RPE cells, exhibited similarities with in vivo choroidal vessels, as confirmed through immunohistochemistry of extracellular matrix markers and vascular-related markers, as well as choroid angiogenesis sprouting assay analysis. The effectiveness of our in vitro model was demonstrated in assessing vascular changes induced by drugs targeting vasoregulation. Our model offers a valuable tool for gaining insights into the pathological mechanisms underlying choroid development and the progression of choroidal vascular diseases.