A hybrid DCS and TD-NIRS device for monitoring tissue oxygenation and perfusion, towards ICU applications

Background: Blood oxygen level-dependent magnetic resonance imaging (BOLD-MRI) has been widely used to assess renal oxygenation changes in different kidney diseases in recent years. This study was designed to evaluate and compare renal tissue oxygenation using 2 BOLD-MRI analysis methods, namely, the regional and whole-kidney region of interest (ROI) selection methods. Methods: The study ended up with 10 healthy controls and 40 chronic kidney disease (CKD) patients without dialysis. Their renal BOLD-MRI data were analyzed using whole-kidney ROI selection method and compared with regional ROI selection method. Results: We found the cortical, medullary, and whole-kidney R2* values were significantly higher in CKD patients than those in controls. Compared with the regional ROI selection method, the whole-kidney ROI selection method yielded higher cortical R2* values in both controls and CKD patients. The whole-kidney R2* values of deteriorating renal function group were significantly higher than those in stable renal function group. Conclusions: Cortical and medullary oxygenation was decreased significantly in CKD patients compared with the healthy controls, particularly in the medulla. The whole-kidney R2* values were positively correlated with kidney function and inversely correlated with the estimated glomerular filtration rate and effective renal plasma flow. Whole-Kidney R2* value might effectively predict the progression of renal function in patients with CKD.

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Influence of Oxidative Stress on Time-Resolved Oxygen Detection by [Ru(Phen)3]2+ In Vivo and In Vitro

Molecules ◽

10.3390/molecules26020485 ◽

2021 ◽

Vol 26 (2) ◽

pp. 485

Author(s):

Veronika Huntosova ◽

Denis Horvath ◽

Robert Seliga ◽

Georges Wagnieres

Keyword(s):

Oxidative Stress ◽

Tissue Oxygenation ◽

Intact Cell ◽

Molecular Probes ◽

Stress Factors ◽

Time Resolved ◽

Invasive Approach ◽

Oxygen Detection

Detection of tissue and cell oxygenation is of high importance in fundamental biological and in many medical applications, particularly for monitoring dysfunction in the early stages of cancer. Measurements of the luminescence lifetimes of molecular probes offer a very promising and non-invasive approach to estimate tissue and cell oxygenation in vivo and in vitro. We optimized the evaluation of oxygen detection in vivo by [Ru(Phen)3]2+ in the chicken embryo chorioallantoic membrane model. Its luminescence lifetimes measured in the CAM were analyzed through hierarchical clustering. The detection of the tissue oxygenation at the oxidative stress conditions is still challenging. We applied simultaneous time-resolved recording of the mitochondrial probe MitoTrackerTM OrangeCMTMRos fluorescence and [Ru(Phen)3]2+ phosphorescence imaging in the intact cell without affecting the sensitivities of these molecular probes. [Ru(Phen)3]2+ was demonstrated to be suitable for in vitro detection of oxygen under various stress factors that mimic oxidative stress: other molecular sensors, H2O2, and curcumin-mediated photodynamic therapy in glioma cancer cells. Low phototoxicities of the molecular probes were finally observed. Our study offers a high potential for the application and generalization of tissue oxygenation as an innovative approach based on the similarities between interdependent biological influences. It is particularly suitable for therapeutic approaches targeting metabolic alterations as well as oxygen, glucose, or lipid deprivation.

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Effect of hyperoxia and vascular occlusion on tissue oxygenation measured by near infra-red spectroscopy (InSpectra™): a volunteer study

Anaesthesia ◽

10.1111/j.1365-2044.2012.07265.x ◽

2012 ◽

Vol 67 (11) ◽

pp. 1237-1241 ◽

Cited By ~ 5

Author(s):

B. Kyle ◽

E. Litton ◽

K. M. Ho

Keyword(s):

Tissue Oxygenation ◽

Vascular Occlusion ◽

Volunteer Study ◽

Infra Red

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