Application of a stretched-exponential model for morphometric analysis of accelerated diffusion-weighted 129Xe MRI of the rat lung

Ouriadov, Alexei; Fox, Matthew S.; Lindenmaier, Andras; Stirrat, Elaine; Serrai, Haçène; Santyr, Giles

doi:10.1007/s10334-020-00860-6

Cited by 3 publications

(3 citation statements)

References 46 publications

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“…Damage to the respiratory portion of the lungs is confirmed by a significant increase in the average values of dys-and atelectasis and zones of emphysematous expansion of the alveoli, which to some extent agrees with the data of scientists [9,16]. Morphometric studies [15,18] noted a significant increase in the rate of fibrosis and hyperplasia of lymphoid tissue under conditions of chronic chemical exposure, which to some extent agrees with our studies. Experimental studies [13] indicated the development of degenerative, inflammatory and sclerotic changes in the components of the respiratory portion.…”

Section: Discussionsupporting

confidence: 91%

Morphometric analysis of lungs parameters under conditions of simulated burn injury

et al. 2023

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Thermal burns are one of the most traumatic and physically exhausting injuries. Among the many factors that are decisive for a burn injury, the relationship between the temperature of the damaging agent and the duration of exposure is important. The term of exposure and high temperature determine the depth of the lesion. During burns, hypoxic, hemodynamic and metabolic disorders occur, which lead to changes in the structures and functions of internal organs. There are various ways of developing the respiratory system disorders after a burn injury to the skin: direct thermal damage to the respiratory tract, damage to the lungs by toxins of endogenous origin. After thermal exposure, there is a reorganization of the airiness of the lung tissue, its increase and combination with the phenomena of bronchospasm. A complex of morphological changes develops in the lungs, which includes degenerative changes in the walls of blood vessels and their permeability, a violation of the typical structure of the alveoli, the appearance of foci of distelectases and atelectasis, signs of inflammatory reactions, as well as the detection of areas of clusters of alveolar macrophages in places of hemorrhages. The aim of our study was to establish changes in the morphometric parameters of the lungs during experimental thermal injury to the skin. The results of the morphometric analysis showed that in the early stages (1st, 7th days) after experimental thermal injury to the skin, there is a reorganization of the structural components of the lungs with signs of an adaptive and compensatory nature, as well as destructive changes. It was established that the average values of the area of bronchi, lymphoid tissue statistically significantly increased from the indicators of the intact group animals, while the percentage of unchanged lung tissue significantly decreased in the respiratory portion. It was found that in the late stages of the experiment (14th, 21st days), inflammatory and sclerotic changes in the components of the respiratory portion occurred, which were manifested by a significant increase in the average values of dys- and atelectasis and the relative areas of emphysematously changed lung tissue relative to the indicators of the intact group. The values of the relative fractions of unchanged lung tissue were significantly reduced, which indicated deep degenerative-destructive changes in the organ.

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Section: Discussionsupporting

confidence: 91%

Morphometric analysis of lungs parameters under conditions of simulated burn injury

et al. 2023

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“…Moreover, by using the technique of chemical shift saturation recovery (CSSR) MR spectroscopy (MRS), gas exchange functional parameters at the alveolar-capillary interface can be obtained. [14][15][16][17][18] Xe MR has been used to evaluate the impaired gas exchange function caused by ALI. 19 However, this important technique has not yet been employed for evaluating the dynamic physiological changes in the progression of ALI, especially the gas exchange function, which is critical for the treatment and management of ALI in the clinic.…”

Section: Introductionmentioning

confidence: 99%

“…Combined with diffusion‐weighted imaging (DWI), it can quantify the lung morphology changes caused by various diseases, such as chronic obstructive pulmonary disease (COPD) and idiopathic pulmonary fibrosis (IPF). Moreover, by using the technique of chemical shift saturation recovery (CSSR) MR spectroscopy (MRS), gas exchange functional parameters at the alveolar–capillary interface can be obtained 14–18 . HP 129 Xe MR has been used to evaluate the impaired gas exchange function caused by ALI 19 .…”

Section: Introductionmentioning

confidence: 99%

Dynamic evaluation of acute lung injury using hyperpolarized ¹²⁹Xe magnetic resonance

Zhang,

Li,

et al. 2023

NMR in Biomedicine

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Prognosticating acute lung injury (ALI) is challenging, in part because of a lack of sensitive biomarkers. Hyperpolarized gas magnetic resonance (MR) has unique advantages in pulmonary function measurement and can provide promising biomarkers for the assessment of lung injuries. Herein, we employ hyperpolarized 129Xe MRI and generate a number of imaging biomarkers to detect the pulmonary physiological and morphological changes during the progression of ALI in an animal model. We find the measured ratio of 129Xe in red blood cells to interstitial tissue/plasma (RBC/TP) is significantly lower in the ALI group on the second (0.32 ± 0.03, p = 0.004), seventh (0.23 ± 0.03, p < 0.001), and 14th (0.29 ± 0.04, p = 0.001) day after lipopolysaccharide treatment compared with that in the control group (0.41 ± 0.04). In addition, significant differences are also observed for RBC/TP measurements between the second and seventh day (p = 0.001) and between the seventh and 14th day (p = 0.018) in the ALI group after treatment. Besides RBC/TP, significant differences are also observed in the measured exchange time constant (T) on the second (p = 0.038) and seventh day (p = 0.009) and in the measured apparent diffusion coefficient (ADC) and alveolar surface‐to‐volume ratio (SVR) on the 14th day (ADC: p = 0.009 and SVR: p = 0.019) after treatment in the ALI group compared with that in the control group. These findings indicate that the parameters measured with 129Xe MR can detect the dynamic changes in pulmonary structure and function in an ALI animal model.

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Feasibility of Dynamic Inhaled Gas MRI-Based Measurements Using Acceleration Combined with the Stretched Exponential Model

et al. 2023

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Dynamic inhaled gas (3He/129Xe/19F) MRI permits the acquisition of regional fractional-ventilation which is useful for detecting gas-trapping in lung-diseases such as lung fibrosis and COPD. Deninger’s approach used for analyzing the wash-out data can be substituted with the stretched-exponential-model (SEM) because signal-intensity is attenuated as a function of wash-out-breath in 19F lung imaging. Thirteen normal-rats were studied using 3He/129Xe and 19F MRI and the ventilation measurements were performed using two 3T clinical-scanners. Two Cartesian-sampling-schemes (Fast-Gradient-Recalled-Echo/X-Centric) were used to test the proposed method. The fully sampled dynamic wash-out images were retrospectively under-sampled (acceleration-factors (AF) of 10/14) using a varying-sampling-pattern in the wash-out direction. Mean fractional-ventilation maps using Deninger’s and SEM-based approaches were generated. The mean fractional-ventilation-values generated for the fully sampled k-space case using the Deninger method were not significantly different from other fractional-ventilation-values generated for the non-accelerated/accelerated data using both Deninger and SEM methods (p > 0.05 for all cases/gases). We demonstrated the feasibility of the SEM-based approach using retrospective under-sampling, mimicking AF = 10/14 in a small-animal-cohort from the previously reported dynamic-lung studies. A pixel-by-pixel comparison of the Deninger-derived and SEM-derived fractional-ventilation-estimates obtained for AF = 10/14 (≤16% difference) has confirmed that even at AF = 14, the accuracy of the estimates is high enough to consider this method for prospective measurements.

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Application of a stretched-exponential model for morphometric analysis of accelerated diffusion-weighted 129Xe MRI of the rat lung

Cited by 3 publications

References 46 publications

Morphometric analysis of lungs parameters under conditions of simulated burn injury

Morphometric analysis of lungs parameters under conditions of simulated burn injury

Dynamic evaluation of acute lung injury using hyperpolarized ¹²⁹Xe magnetic resonance

Feasibility of Dynamic Inhaled Gas MRI-Based Measurements Using Acceleration Combined with the Stretched Exponential Model

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Application of a stretched-exponential model for morphometric analysis of accelerated diffusion-weighted 129Xe MRI of the rat lung

Cited by 3 publications

References 46 publications

Morphometric analysis of lungs parameters under conditions of simulated burn injury

Morphometric analysis of lungs parameters under conditions of simulated burn injury

Dynamic evaluation of acute lung injury using hyperpolarized 129Xe magnetic resonance

Feasibility of Dynamic Inhaled Gas MRI-Based Measurements Using Acceleration Combined with the Stretched Exponential Model

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Dynamic evaluation of acute lung injury using hyperpolarized ¹²⁹Xe magnetic resonance