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Evaluation of the Intraoperative Blood Flow of Pedicled Perforator Flaps Using Indocyanine Green-fluorescence Angiography
摘要： Background: Although indocyanine-green fluorescence angiography (ICG-FA) has been established as a useful tool to assess perfusion in free tissue transfer, only few studies have applied this modality to pedicled perforator flaps. As both volume and reach of pedicled perforator flaps are limited and tip necrosis often equals complete flap failure, ICG-FA may help to detect hypoperfusion in pedicled flaps. Methods: In 5 patients, soft tissue reconstruction was achieved with pedicled perforator flaps. ICG-FA was utilized intraoperatively to visualize flap perfusion. Results: Three pedicled anterolateral thigh flap flaps and 2 propeller flaps were transferred. ICG-FA detected hypoperfusion in 2 flaps. No flap loss occurred; in 2 cases, prolonged wound healing was encountered. Conclusions: ICG-FA confirmed clinical findings and reliably detected tissue areas with hypoperfusion. A clear cut-off point between nonvital tissue and such that stabilized in the following clinical course could not be found. ICG-FA is a promising technology which could also be used in pedicled perforator flaps.
关键词： flap perfusion,soft tissue reconstruction,pedicled perforator flaps,indocyanine-green fluorescence angiography
更新于2025-09-11 14:15:04
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Laser-based Techniques for Microcirculatory Assessment in Orthopedics and Trauma Surgery
摘要： Microcirculatory integrity and proper function are the cornerstones to tissue nourishment and viability. In the clinical environment extended immobility, injuries, and inflammatory reactions demand local microcirculatory adaption to provide adequate supply. Assessment of endothelial adjustment capability and microcirculatory perfusion status, as direct or surrogate markers of disease, are therefore of uttermost interest to the treating physician. Given the simple, noninvasive, nonradiating nature of laser-based techniques for bedside or intraoperative microcirculatory perfusion assessment, this article’s objective is to present a comprehensive overview of available techniques, their technological aspects, and current application. Advantages of individual methods are pointed out and compared with each other. The areas of medical utilization relevant to orthopedics and trauma surgery are exemplified and their available evidence elaborated. A particular focus is put on laser speckle contrast imaging, with its current and future influence on medical practice.
关键词： noninvasive cutaneous microcirculatory perfusion assessment,laser Doppler flowmetry,laser Doppler imaging,Laser speckle contrast imaging
更新于2025-09-11 14:15:04
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The feasibility of low-dose CT perfusion imaging in gastric cancer
摘要： PURPOSE: To investigate feasibility of applying low-dose CT perfusion imaging (CTPI) to diagnose gastric cancer. MATERIALS AND METHODS: Twenty patients with gastric cancer con?rmed by endoscopic biopsy were undergone routine dose (120 kV, 100 mA) and low-dose (120 kV, 50 mA) CTPI examination, respectively. The original data were processed by body perfusion software, and the perfusion parameters values including blood ?ow (BF), blood volume (BV) and permeability surface (PS) of gastric cancer were measured. Statistical data analyses including paired-samples t test, Pearson correlation analysis and Bland-Altman consistency test were used to compare the perfusion parameters values between the routine dose and low-dose CTPI examinations. Radiation dosage, which the patients received during two CTPI examinations, was also calculated and compared. RESULTS: There were no statistical differences in the BF, BV and PS values between routine dose group and low-dose group (P > 0.05), and there were signi?cant correlation in the BF, BV and PS values between two groups (P < 0.01). The consistency of BF and BV values between the two groups was preferable to that of PS value. The radiation dosage of the low-dose group was much less than that of routine dose group, and the CTDIvol and DLP values of low-dose CTPI were decreased by 50%, respectively. CONCLUSION: The parameters BF and BV values may play a valuable role in the diagnosis and assessment of gastric cancer in low-dose CTPI examination.
关键词： gastric cancer,computed tomography,Low-dose,perfusion imaging
更新于2025-09-10 09:29:36
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Perfusion und Spektroskopie in der multimodalen Bildgebung der progressiven multifokalen Leukenzephalopathie
摘要： Die progressive multifokale Leukenzephalopathie (PML) ist eine seltene Erkrankung, die zur Demyelinisierung des zentralen Nervensystems führt. Diese wird ausgel?st durch eine Reaktivierung des John-Cunningham-Virus (JC-Virus) in den Oligodendrozyten, welches bei etwa 50 % der Menschen in der Allgemeinbev?lkerung nachweisbar ist und nur bei einer Immundefizienz eine PML bedingen kann. Typische Ursachen der PML sind deswegen eine HIV-Infektion, h?matologische Erkrankungen oder – heutzutage von besonderer Wichtigkeit – die immunsuppressive Therapie, wie die Natalizumab-Therapie der multiplen Sklerose. Die Diagnosestellung kann aufgrund der Vielzahl von m?glichen Differenzialdiagnosen erschwert sein, ist jedoch für den Patienten von gro?er Therapierelevanz.
关键词： John-Cunningham-Virus,Spektroskopie,Perfusion,progressive multifokale Leukenzephalopathie,JC-Virus,Immunsuppression,PML,Natalizumab-Therapie,multimodale Bildgebung
更新于2025-09-10 09:29:36
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The use of pulse oximeter in hemodynamic assessment
摘要： Objective: Identify and analyze the scientific literature on pulse oximeter with plethysmograph for assessing hemodynamic perfusion. Method: this is an integrative literature review, conducted in January and February 2012 on the Virtual Health Library. Studies published from 2000 to 2011 were selected. Results: after evaluating titles, 24 articles were selected for reading of the abstracts; 17 articles were excluded for not addressing the issue at stake, something which resulted in the inclusion of 7 articles in the sample. Conclusion: nursing care and multidisciplinary team care for the patient using pulse oximeter with plethysmograph may associate non-invasive parameters for hemodynamic assessment of perfusion in everyday clinical practice. Descriptors: Oximetry, Perfusion, Hemodynamics, Nursing.
关键词： Oximetry,Perfusion,Nursing,Hemodynamics
更新于2025-09-10 09:29:36
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Evaluation of Ocular Perfusion in Alzheimer’s Disease Using Optical Coherence Tomography Angiography
摘要： Background: There is increasing evidence for the involvement of cerebrovascular factors in Alzheimer’s disease (AD). Objective: To evaluate retinal and optic nerve head perfusion in patients with AD using optical coherence tomography angiography (OCTA), and to analyze the correlations of quantitative OCTA metrics with AD pathology and vascular cerebral lesions in AD patients. Methods: 36 eyes of 36 patients with AD (study group) and 38 eyes of 38 healthy subjects (control group) were prospectively included in this study. OCTA was performed using RTVue XR Avanti with AngioVue. In addition, patients underwent a detailed ophthalmological and neurological examination including Mini-Mental State Examination, cerebral magnetic resonance imaging, and amyloid-β (Aβ) and tau levels in the cerebrospinal fluid (CSF). Results: The flow density in the superficial retinal OCT angiogram of the macula in the study group was significantly lower compared to the control group (p = 0.001). There was a significant correlation between the flow density in the superficial retinal OCT angiogram of the macula, as measured using OCTA, and the Fazekas scale (Spearman’s correlation coefficient = –0.520; p = 0.003). There was no significant correlation between the Aβ or tau levels in the CSF and the flow density data. Conclusion: Patients with AD showed a reduced flow density in the radial peripapillary capillaries layer and in the superficial retinal OCT angiogram when compared with healthy controls. The reduced retinal flow density measured using OCTA is not specifically associated with AD pathology but is associated with the vascular cerebral lesions in AD.
关键词： optical coherence tomography angiography,retinal and optic nerve head perfusion,Alzheimer’s disease,flow density
更新于2025-09-04 15:30:14
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Quantitative Assessment of the Blood Perfusion of the Gastric Conduit by Indocyanine Green Imaging
摘要： Background: Indocyanine green (ICG) ?uorescence imaging has been used to assess the blood perfusion of the gastrointestinal tract in surgery. Especially, it was used to determine the best anastomotic site. However, in previous studies, ICG ?uorescence was judged subjectively based on the visual appearance. This study evaluated the usefulness of our novel method to quantitatively assess the blood perfusion of the gastric conduit in esophagectomy based on ICG ?uorescence. Materials and methods: Twenty patients who underwent esophagectomy with gastric conduit reconstruction were prospectively investigated. Using a camera in contact with the surface of the stomach, ICG images were quantitatively evaluated using “ROIs”, a software program that quanti?ed the ?uorescence intensity and created a time-?uorescence intensity curve to assess the blood perfusion three times intraoperatively. Results: No postoperative esophago-gastrostomy leakage developed. However, after preparing the gastric conduit and just before anastomosis, the maximum increase in ?uorescence intensity (FImax) signi?cantly decreased (48.8 (cid:1) 26.0 and 31.5 (cid:1) 14.9 versus 84.9 (cid:1) 28.2; P < 0.001 and P < 0.001, respectively), and the time to reach FImax was signi?cantly extended (60 (cid:1) 35.4 and 58.3 (cid:1) 34.9 versus 18.9 (cid:1) 6.5; P < 0.001 and P < 0.002, respectively), in comparison to the control value. Just before anastomosis, 18 cases (90%) showed an identical pattern characterized by an obtuse and low arterial in?ow peak and a slow rise of ?uorescence intensity over time, indicating a decreased blood ?ow. Conclusions: The quantitative analysis of ICG ?uorescence imaging could objectively prove a decrease in blood perfusiondwhich could not be determined macroscopicallydin the gastric conduit before esophageal reconstruction. The results from the present and further studies may indicate its clinical value.
关键词： Gastric conduit,Anastomotic leakage,Indocyanine green,Esophagectomy,Blood perfusion,Quantitative assessment
更新于2025-09-04 15:30:14
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The repeatability of superficial retinal vessel density measurements in eyes with long axial length using optical coherence tomography angiography
摘要： Background: To investigate the repeatability of superficial retinal vessel density measurements in healthy eyes with long axial length (AL) using optical coherence tomography angiography (OCTA). Methods: There were 60 eyes of 31 volunteers enrolled in this cross-sectional observational study. All subjects underwent OCTA, AL and refraction test. The enrolled eyes were divided into the long AL group (26 mm ≤ AL < 28 mm) and normal AL group (22 mm ≤ AL < 26 mm). The vessel length density (VLD), perfusion density (PD), and fovea avascular zone (FAZ) of the superficial retinal vessel were evaluated. Repeatability was assessed by intraclass correlation coefficients (ICCs) and Bland-Altman analysis. Pearson’s r correlation was used to analyze the relation of AL and the absolute difference between two measurements. Results: The 3 × 3 mm scan pattern showed good repeatability with all ICCs over 0.7. For all parameters of all scan patterns, the ICCs of the normal AL group were distinctly higher than those of the long AL group; this finding was also confirmed by Bland-Altman analysis. The correlation analysis of AL and repeatability of OCTA parameters showed significant negative correlations between the ALs and repeatability of VLD in 6 × 6 mm inner ring (r2 = 0.13, p = 0.01), VLD in 6 × 6 mm outer ring (r2 = 0.09, p = 0.02) and PD in 6 × 6 mm outer ring (r2 = 0.08, p = 0.03). Conclusions: The AL and the scanned area will both affect the repeatability of superficial retinal vessel density measurements in OCTA.
关键词： Fovea avascular zone,Vessel length density,Myopia,Optical coherence tomography angiography,Repeatability,Perfusion density
更新于2025-09-04 15:30:14
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Functional Capillary Density for in Vivo Estimation of Intestinal Perfusion using Real-Time Confocal Endomicroscopy
摘要： Background and aim: Confocal Laser Endomicroscopy (CLE) has been successfully used to appreciate microcirculation changes of the digestive mucosa. Our aim was to evaluate CLE scanning complemented by functional capillary density area (FCD-A) estimation to define the micro-vessel status in a reiterate, long-lasting porcine model of bowel ischemia. Materials and methods: A laparotomy was performed in 4 pigs, and a segmental (3–4 cm) ischemia of the sigmoid colon was induced with vascular clamps. Ischemic and perfused regions were clinically defined. After an injection of 5 ml of sodium fluorescein 10% (Fluocyne, SERB, Paris, France), the Cellvizio? confocal probe (Mauna Kea Technologies, Paris, France) was directly applied onto the mucosa’s surface through a full-thickness enterotomy. Both ischemic area (IA) and control region-perfused area (PA) – were scanned and video sequences were recorded. Results: Confocal evaluation of the ischemic area revealed a different aspect of the mucosal tissue when compared to the normal perfused area. Statistically, FCD-A at the perfused area was significantly higher when compared to the ischemic area, irrespective of the time point. After 1 hour, FCD-A was (0.189 ± 0.094 vs. 0.365 ± 0.030; p=0.0001), after 2 hours (0.252 ± 0.056 vs. 0.389 ± 0.024; p<0.0001), after 3 hours (0.252 ± 0.050 vs. 0.353 ± 0.030; p=0.0001) and after 4 hours (0.262 ± 0.044 vs. 0.358 ± 0.019; p<0.0001), at ischemic and perfused areas respectively. Conclusions: Confocal imaging allows real-time discrimination between perfused and ischemic areas of the bowel using morphological clues, while the functional capillary density area adds a quantitative measurement.
关键词： Cellvizio? system,Quantitative assessment of bowel perfusion,Functional capillary density area,Confocal laser endomicroscopy
更新于2025-09-04 15:30:14
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Changes in cerebral oxygenation and cerebral blood flow during hemodialysis – A simultaneous near-infrared spectroscopy and positron emission tomography study
摘要： Near-infrared spectroscopy (NIRS) is used to monitor cerebral tissue oxygenation (rSO2) depending on cerebral blood flow (CBF), cerebral blood volume and blood oxygen content. We explored whether NIRS might be a more easy applicable proxy to [15O]H2O positron emission tomography (PET) for detecting CBF changes during hemodialysis. Furthermore, we compared potential determinants of rSO2 and CBF. In 12 patients aged (cid:2) 65 years, NIRS and PET were performed simultaneously: before (T1), early after start (T2), and at the end of hemodialysis (T3). Between T1 and T3, the relative change in frontal rSO2 (DrSO2) was (cid:3)8 (cid:4) 9% (P ? 0.001) and (cid:3)5 (cid:4) 11% (P ? 0.08), whereas the relative change in frontal gray matter CBF (DCBF) was (cid:3)11 (cid:4) 18% (P ? 0.009) and (cid:3)12 (cid:4) 16% (P ? 0.007) for the left and right hemisphere, respectively. DrSO2 and DCBF were weakly correlated for the left (r 0.31, P ? 0.4), and moderately correlated for the right (r 0.69, P ? 0.03) hemisphere. The Bland-Altman plot suggested underestimation of DCBF by NIRS. Divergent associations of pH, pCO2 and arterial oxygen content with rSO2 were found compared to corres- ponding associations with CBF. In conclusion, NIRS could be a proxy to PET to detect intradialytic CBF changes, although NIRS and PET capture different physiological parameters of the brain.
关键词： cerebral oximetry,hemodialysis,water-PET,Brain perfusion,NIRS
更新于2025-09-04 15:30:14