Quantifying cerebral blood flow in an adult pig ischemia model by a depth-resolved dynamic contrast-enhanced optical method

Elliott, Jonathan T.; Diop, Mamadou; Morrison, Laura; d’Esterre, Christopher D; Lee, Ting Yim; Lawrence, Keith St.

doi:10.1016/j.neuroimage.2014.03.023

Cited by 29 publications

(37 citation statements)

References 40 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Flow reductions caused by hypocapnia are not as great as caused by ischemia; however, the good agreement with the CTP results is further evidence of the ability of DCS to measure CBF changes accurately. The cerebral vascular reactivity measured with the B DM was (−2.3 ± 0.2)% per mmHg of paCO 2 , which is in good agreement with our previous study, which used the same animal model (juvenile pigs) and a contrast-enhanced NIRS technique to measure CBF [32]. Likewise, these findings confirm previous validation studies involving both animal models and human subjects that have shown a good correlation between BFI B and CBF changes measured by other modalities [12,33].…”

Section: Discussionsupporting

confidence: 91%

Assessment of the best flow model to characterize diffuse correlation spectroscopy data acquired directly on the brain

Verdecchia¹,

Diop²,

Morrison³

et al. 2015

Biomed. Opt. Express

Self Cite

View full text Add to dashboard Cite

Diffuse correlation spectroscopy (DCS) is a non-invasive optical technique capable of monitoring tissue perfusion. The normalized temporal intensity autocorrelation function generated by DCS is typically characterized by assuming that the movement of erythrocytes can be modeled as a Brownian diffusion-like process instead of by the expected random flow model. Recently, a hybrid model, referred to as the hydrodynamic diffusion model, was proposed, which combines the random and Brownian flow models. The purpose of this study was to investigate the best model to describe autocorrelation functions acquired directly on the brain in order to avoid confounding effects of extracerebral tissues. Data were acquired from 11 pigs during normocapnia and hypocapnia, and flow changes were verified by computed tomography perfusion (CTP). The hydrodynamic diffusion model was found to provide the best fit to the autocorrelation functions; however, no significant difference for relative flow changes measured by the Brownian and hydrodynamic diffusion models was observed.

show abstract

Section: Discussionsupporting

confidence: 91%

Assessment of the best flow model to characterize diffuse correlation spectroscopy data acquired directly on the brain

Verdecchia¹,

Diop²,

Morrison³

et al. 2015

Biomed. Opt. Express

Self Cite

View full text Add to dashboard Cite

show abstract

“…Nevertheless, there is a continuing effort to develop optical methods that can more directly target key cerebral parameters such as CBF and cerebral oxidative metabolism 25, 26 . DCE NIRS is one such approach and has been previously used to detect CBF abnormalities in stroke patients 15, 27 and in animal models of cerebral ischemia 16 . The work presented in this study extends the potential clinical utility of NIRS by presenting a DCE method of assessing BBB integrity.…”

Section: Discussionmentioning

confidence: 99%

“…Methods to enhance depth sensitivity, in particular, time-resolved detection 11, 36 , have been developed and shown to benefit DCE NIRS applications in adults 10, 37 , including a study of patients with known BBB dysfunction 17 . Furthermore, the incorporation of optical reconstruction into the analysis of DCE NIRS has been shown to provide accurate CBF estimates in large animal models than mimic the typical thickness of the adult human head 16, 29 . An additional consideration with regards to measuring the PS product in the adult brain is the influence of possible contrast agent leakage into scalp tissue, which lacks the tight conjunctions between endothelium cells found in cerebral capillaries.…”

Section: Discussionmentioning

confidence: 99%

See 1 more Smart Citation

Quantification of blood-brain barrier permeability by dynamic contrast-enhanced NIRS

Milej

Abdalmalak

Desjardins

et al. 2017

Sci Rep

Self Cite

View full text Add to dashboard Cite

The blood-brain barrier (BBB) is integral to maintaining a suitable microenvironment for neurons to function properly. Despite its importance, there are no bedside methods of assessing BBB disruption to help guide management of critical-care patients. The aim of this study was to demonstrate that dynamic contrast-enhanced (DCE) near-infrared spectroscopy (NIRS) can quantify the permeability surface-area product (PS) of the BBB. Experiments were conducted in rats in which the BBB was opened by image-guided focused ultrasound. DCE-NIRS data were acquired with two dyes of different molecular weight, indocyanine green (ICG, 67 kDa) and 800CW carboxylate (IRDye, 1166 Da), and PS maps were generated by DCE computer tomography (CT) for comparison. Both dyes showed a strong correlation between measured PS values and sonication power (R2 = 0.95 and 0.92 for ICG and IRDye respectively), and the PS values for IRDye were in good agreement with CT values obtained with a contrast agent of similar molecular weight. These proof-of-principle experiments demonstrate that DCE NIRS can quantify BBB permeability. The next step in translating this method to critical care practice will be to adapt depth sensitive methods to minimize the effects of scalp contamination on NIRS PS values.

show abstract

“…There is therefore the need of extracting from the NIRS signal the information regarding the deep layer, discriminating the contribution coming from the superficial one. A multi-distance approach has been proposed to tackle this issue in the continuous wave (CW) [4,5], in the frequency domain (FD) or in the time domain (TD) [6]. However, with TD NIRS it is possible to discriminate signals coming from different depths without the need of implementing a multi-distance approach [7][8][9][10].…”

Section: Introductionmentioning

confidence: 99%

Effect of a thin superficial layer on the estimate of hemodynamic changes in a two-layer medium by time domain NIRS

Re¹,

Contini²,

Zucchelli³

et al. 2016

Biomed. Opt. Express

View full text Add to dashboard Cite

Abstract:In order to study hemodynamic changes involved in muscular metabolism by means of time domain fNIRS, we need to discriminate in the measured signal contributions coming from different depths. Muscles are, in fact, typically located under other tissues, e.g. skin and fat. In this paper, we study the possibility to exploit a previously proposed method for analyzing time-resolved fNIRS measurements in a two-layer structure with a thin superficial layer. This method is based on the calculation of the timedependent mean partial pathlengths. We validated it by simulating venous and arterial arm cuff occlusions and then applied it on in vivo measurements. ©2016 Optical Society of America

show abstract

Quantifying cerebral blood flow in an adult pig ischemia model by a depth-resolved dynamic contrast-enhanced optical method

Cited by 29 publications

References 40 publications

Assessment of the best flow model to characterize diffuse correlation spectroscopy data acquired directly on the brain

Assessment of the best flow model to characterize diffuse correlation spectroscopy data acquired directly on the brain

Quantification of blood-brain barrier permeability by dynamic contrast-enhanced NIRS

Effect of a thin superficial layer on the estimate of hemodynamic changes in a two-layer medium by time domain NIRS

Contact Info

Product

Resources

About