scholarly journals Dual Energy CT Evaluation of the Severity of Pulmonary Thromboembolism: Correlation of Pulmonary Perfusion Score with CT

2020 ◽  
Vol 17 (3) ◽  
Author(s):  
Selen Bayraktaroglu ◽  
Akın Cinkooglu ◽  
Recep Savas ◽  
Naim Ceylan ◽  
Mustafa Bozdağ ◽  
...  
Keyword(s):  
Partial Pressure ◽  
Significant Positive Correlation ◽  
Pulmonary Thromboembolism ◽  
Main Pulmonary Artery ◽  
Dual Energy ◽  
Gas Analysis ◽  
Dual Energy Ct ◽  
Positive Correlation ◽  
Distribution Maps ◽  
Arterial Blood

Background: Pulmonary thromboembolism (PTE) is an important cause of morbidity and mortality in hospitalized patients and computed tomographic angiography (CTA) has become the gold standard diagnostic examination for suspected PTE. Dual energy computed tomography (DECT) not only detects thromboembolic filling defects but also provides functional perfusion information by generating iodine distribution maps. Objectives: The objective of the study is to determine the value of perfusion defect score (P score) in detection of the severity of acute PTE and to correlate it with pulmonary obstruction score (Qanadli score), other CTA parameters and clinical findings. Patients and Methods: Fifty five patients, with acute PTE who underwent DECT were reviewed. We calculated P score, Qanadli score, ratio of the right ventricle diameter to the left ventricle (RV/LV ratio) and the main pulmonary artery (PA) diameter by using the dual energy CTA images. The correlation between CTA parameters and clinical- echocardiographic data was investigated. Results: Correlation analysis showed a significant positive correlation between the P score and Qanadli score (r = 0.748, P < 0.001). There was also a significant positive correlation between P score and RV/LV ratio (r = 0.432, P = 0.001) and between Qanadli score and RV/LV ratio (r = 0.424 P = 0.001). Echocardiographic data was present in 39 patients (70.9 %). P score was significantly higher in patients with RV dilatation (P = 0.022) and RV dysfunction (P = 0.001) on echocardiography. Likewise, similar interaction was present between Qanadli score and RV dilatation (P = 0.023) and RV dysfunction (P = 0.003). No correlation was present between P score and blood gas analysis [partial pressure of oxygen in arterial blood (PaO2), partial pressure of arterial carbon dioxide (PaCO2),(PaO2)/fraction of inspired oxygen (FiO2), oxygen saturation] and hemodynamic data (blood pressure and pulse). Conclusion: P score is seen as a good adjunctive tool to other CTA parameters and echocardiography in detection of PTE severity. Addition of perfusion changes to clinical risk assessment will help in the management of patients.

Quantification of Lung Perfusion Blood Volume With Dual-Energy CT: Assessment of the Severity of Acute Pulmonary Thromboembolism

2014 ◽  
Vol 203 (2) ◽  
pp. 287-291 ◽  
Author(s):  
Ayami Sakamoto ◽  
Ichiro Sakamoto ◽  
Hiroki Nagayama ◽  
Hirofumi Koike ◽  
Eijun Sueyoshi ◽  
...  
Keyword(s):  
Blood Volume ◽  
Pulmonary Thromboembolism ◽  
Dual Energy ◽  
Lung Perfusion ◽  
Dual Energy Ct ◽  
Acute Pulmonary Thromboembolism

Acute respiratory failure and acute respiratory distress syndrome

2018 ◽  
Author(s):  
Luciano Gattinon ◽  
Eleonora Carlesso
Keyword(s):  
Acute Respiratory Distress Syndrome ◽  
Respiratory Failure ◽  
Respiratory Distress Syndrome ◽  
Respiratory Distress ◽  
Partial Pressure ◽  
Distress Syndrome ◽  
Gas Analysis ◽  
Chronic Obstructive ◽  
Low Oxygen ◽  
Arterial Blood

Respiratory failure (RF) is defined as the acute or chronic impairment of respiratory system function to maintain normal oxygen and CO2 values when breathing room air. ‘Oxygenation failure’ occurs when O2 partial pressure (PaO2) value is lower than the normal predicted values for age and altitude and may be due to ventilation/perfusion mismatch or low oxygen concentration in the inspired air. In contrast, ‘ventilatory failure’ primarily involves CO2 elimination, with arterial CO2 partial pressure (PaCO2) higher than 45 mmHg. The most common causes are exacerbation of chronic obstructive pulmonary disease (COPD), asthma, and neuromuscular fatigue, leading to dyspnoea, tachypnoea, tachycardia, use of accessory muscles of respiration, and altered consciousness. History and arterial blood gas analysis is the easiest way to assess the nature of acute RF and treatment should solve the baseline pathology. In severe cases mechanical ventilation is necessary as a ‘buying time’ therapy. The acute hypoxemic RF arising from widespread diffuse injury to the alveolar-capillary membrane is termed Acute Respiratory Distress Syndrome (ARDS), which is the clinical and radiographic manifestation of acute pulmonary inflammatory states.

scholarly journals Salvage of Suboptimal Enhancement of Pulmonary Artery in Pulmonary CT Angiography Studies: Rapid kVp Switch Dual Energy CT Experience

2020 ◽  
Vol 17 (2) ◽  
Author(s):  
Selen Bayraktaroglu ◽  
Akın Cinkooglu ◽  
Naim Ceylan ◽  
Recep Savas
Keyword(s):  
Pulmonary Embolism ◽  
Image Quality ◽  
Pulmonary Artery ◽  
Imaging Modality ◽  
Main Pulmonary Artery ◽  
Pulmonary Arteries ◽  
Dual Energy ◽  
Dual Energy Ct ◽  
Average Increase ◽  
Noise Ratio

Background: Multidetector computed tomography (MDCT) angiography is considered as the gold standard imaging modality in the evaluation of acute pulmonary embolism. Optimum vascular enhancement is critical for MDCT studies. The suboptimal opacification in pulmonary artery could be salvaged using low-energy virtual monoenergetic images (VMI) at rapid kVp switch dual energy CT. Objectives: To explore the potential improvement in pulmonary artery opacification and to assess the change in image quality parameters in VMI using fast switch kVp dual energy CT. Patients and Methods: The CT images of 877 patients who were referred with a preliminary diagnosis of pulmonary embolism were reviewed. Sixty patients with suboptimal enhancement (< 200 Hounsfeld Unit [HU]) were involved. Standard images (140 kVp) and VMI from 40 to 120 keV were generated. Attenuation, noise, signal to noise ratio (SNR) and contrast to noise ratio (CNR) were measured in the pulmonary artery. Using VMIs, the best image was determined as the image with the main pulmonary artery opacification greater than 200 HU and image quality ≥ 3. Fifty six studies that met these criteria were considered as salvaged. At this best energy level, quantitative parameters were compared with standard images. Results: The mean attenuation of pulmonary arteries was 169.80 HU in standard images in patients with suboptimal enhancement. The attenuations of VMIs at 40, 45, 50, 55, 60, 65, and 70 keV were significantly higher than standard images (P < 0.001). Similar findings were observed with SNR and CNR. In the salvaged patients, the average increase in mean pulmonary artery attenuation was 62% (from 172.61 ± 23.4 to 280.55 ± 40.7), the average increase in SNR was 38% (from 12.1 ± 5.3 to 16.7 ± 7.1) and the average increase in CNR was 48% (9.2 ± 4.3 to 13.7 ± 6) (P < 0.001). Conclusions: Low keV VMI reconstructions significantly increase pulmonary artery attenuation, CNR and SNR compared to standard image reconstructions. Suboptimal CT studies could be salvaged using low keV VMIs.

Acute respiratory failure and acute respiratory distress syndrome

2015 ◽  
Author(s):  
Luciano Gattinon ◽  
Eleonora Carlesso
Keyword(s):  
Acute Respiratory Distress Syndrome ◽  
Respiratory Failure ◽  
Respiratory Distress Syndrome ◽  
Respiratory Distress ◽  
Partial Pressure ◽  
Distress Syndrome ◽  
Gas Analysis ◽  
Chronic Obstructive ◽  
Low Oxygen ◽  
Arterial Blood

Respiratory failure (RF) is defined as the acute or chronic impairment of respiratory system function to maintain normal oxygen and CO2 values when breathing room air. ‘Oxygenation failure’ occurs when O2 partial pressure (PaO2) value is lower than the normal predicted values for age and altitude and may be due to ventilation/perfusion mismatch or low oxygen concentration in the inspired air. In contrast, ‘ventilatory failure’ primarily involves CO2 elimination, with arterial CO2 partial pressure (PaCO2) higher than 45 mmHg. The most common causes are exacerbation of chronic obstructive pulmonary disease (COPD), asthma, and neuromuscular fatigue, leading to dyspnoea, tachypnoea, tachycardia, use of accessory muscles of respiration, and altered consciousness. History and arterial blood gas analysis is the easiest way to assess the nature of acute RF and treatment should solve the baseline pathology. In severe cases mechanical ventilation is necessary as a ‘buying time’ therapy. The acute hypoxemic RF arising from widespread diffuse injury to the alveolar-capillary membrane is termed Acute Respiratory Distress Syndrome (ARDS), which is the clinical and radiographic manifestation of acute pulmonary inflammatory states.

Localisation of aluminium in root apex cells of two Australian perennial grasses by X-ray microanalysis

1998 ◽  
Vol 25 (4) ◽  
pp. 427 ◽  
Author(s):  
Simon A. Crawford ◽  
Alan T. Marshall ◽  
Sabine Wilkens
Keyword(s):  
Significant Positive Correlation ◽  
Root Apex ◽  
Root Cap ◽  
Perennial Grasses ◽  
Elemental Distribution ◽  
X Ray ◽  
Positive Correlation ◽  
Distribution Maps ◽  
Meristematic Cells ◽  
Root Apices

To determine if an increased aluminium (Al) sensitivity is the result of greater accumulation of Al in root apices, the quantity and distribution of Al in root apex cells of Danthonia linkii Kunth and Microlaena stipoides (Labill.) R.Br. was investigated by X-ray microanalysis. Seedlings were grown in nutrient solution with 0, 185 and 370 µM total Al for 24 h after which the terminal 5 mm of the roots were excised, rapidly frozen and embedded using freeze-substitution. Elemental distribution maps of root apices showed that Al had accumulated in the nuclei of root cap and meristematic cells in Al-stressed roots of D. linkii but not in M. stipoides. Al appeared to be co-localised with phosphorous (P) in the nuclei of these cells. Quantitation of Al revealed that Al-stressed root apex cells of D. linkiiaccumulated significantly more Al than M. stipoides. Exposure of D. linkii roots to Al resulted in substantial increases in the P content of root apex cells, and a significant positive correlation was found between Al and P in both root cap and meristematic cells. Analysis of intracellular structures showed that the majority of Al had accumulated in the nuclei of cells. A significant positive correlation was found between Al and P in the nuclei, but not in the cytoplasm or cell walls. No positive correlation was found between Al and P in root apex cells of M. stipoides.

scholarly journals Comparison of Dual- and Single-Source Dual-Energy CT for Diagnosis of Acute Pulmonary Artery Embolism

2020 ◽  
Author(s):  
Bernhard Petritsch ◽  
Pauline Pannenbecker ◽  
Andreas Max Weng ◽  
Simon Veldhoen ◽  
Jan-Peter Grunz ◽  
...  
Keyword(s):  
Pulmonary Embolism ◽  
Image Quality ◽  
Radiation Dose ◽  
Dual Energy ◽  
Dual Energy Ct ◽  
Suspected Pulmonary Embolism ◽  
Effective Radiation Dose ◽  
Distribution Maps ◽  
Filter Group ◽  
Effective Radiation

Purpose Comparison of dual-source dual-energy CT (DS-DECT) and split-filter dual-energy CT (SF-DECT) regarding image quality and radiation dose in patients with suspected pulmonary embolism. Materials and Methods We retrospectively analyzed pulmonary dual-energy CT angiography (CTPA) scans performed on two different CT scanners in 135 patients with suspected pulmonary embolism (PE). Scan parameters for DS-DECT were 90/Sn150 kV (n = 68 patients), and Au/Sn120 kV for SF-DECT (n = 67 patients). The iodine delivery rate was 1400 mg/s in the DS-DECT group vs. 1750 mg/s in the SF-DECT group. Color-coded iodine distribution maps were generated for both protocols. Objective (CT attenuation of pulmonary trunk [HU], signal-to-noise ratio [SNR], contrast-to-noise ratio [CNR]) and subjective image quality parameters (two readers [R], five-point Likert scale), as well as radiation dose parameters (effective radiation dose, size-specific dose estimations [SSDE]) were compared. Results All CTPA scans in both groups were of diagnostic image quality. Subjective CTPA image quality was rated as good or excellent in 80.9 %/82.4 % (R1 / R2) of DS-DECT scans, and in 77.6 %/76.1 % of SF-DECT scans. For both readers, the image quality of split-filter iodine distribution maps was significantly lower (p < 0.05) with good or excellent ratings in only 43.3 %/46.3 % (R1 / R2) vs. 83.8 %/88.2 % for maps from DS-DECT. The HU values of the pulmonary trunk did not differ between the two techniques (p = n. s.), while both the SNR and CNR were significantly higher in the split-filter group (p < 0.001; p = 0.003). Both effective radiation dose (2.70 ± 1.32 mSv vs. 2.89 ± 0.94 mSv) and SSDE (4.71 ± 1.63 mGy vs. 5.84 ± 1.11 mGy) were significantly higher in the split-filter group (p < 0.05). Conclusion The split-filter allows for dual-energy imaging of suspected pulmonary embolism but is associated with lower iodine distribution map quality and higher radiation dose. Key points:  Citation Format

scholarly journals Evaluation of pulmonary function for estimation of peak oxygen consumption through the respiratory gas analysis and allometric equation in boy student

2017 ◽  
Vol 6 (1) ◽  
pp. 32-38
Author(s):  
Keyvan Hejazi ◽  
Seyyed Reza Attarzadeh Hosseini
Keyword(s):  
Oxygen Consumption ◽  
Pulmonary Function ◽  
Significant Positive Correlation ◽  
Allometric Equation ◽  
Gas Analysis ◽  
The Body ◽  
Chest Circumference ◽  
Peak Oxygen Consumption ◽  
Positive Correlation ◽  
Physiological Variables

Purpose: Allometric is a method for the expression of relationship between the physiological variables, anatomical with unit of the body size that through mathematical methods can calculate vital capacity. The aim of this study was to evaluation of pulmonary function for estimation of peak oxygen consumption through the respiratory gas analysis and allometric equation in boy student. Methods: In this causal after the occurrence study, 80 subjects were selected by convenience sampling. Characteristics of anthropometric, chest circumference (diameter and depth of the chest), and for estimation of peak oxygen consumption, Bruce test, where was measured using the validated methods. Data were analyzed using Pearson correlation and multiple regressions in SPSS version 16. Result: There were not significant correlations between TV, IRV, ERV, and FVC with peak oxygen consumption. While, There was significant positive correlation between FVC and peak oxygen consumption (p=0.041 & r=0.229) and between amount of FVC of system with FVC of formula (p=0.00 & r=1.00). A significant correlation between FVC and peak oxygen consumption. According to this result the following model was developed: Vo2max= a+(1.761*FVC)+(0.319*age)+(0.284* chest circumference).Conclusion: The results indicated that There was significant positive correlation between amount of FVC of system with FVC of formula. Therefore, it can be concluded that to gain awareness of maximal oxygen uptake, in the absence of other laboratory methods, can be used allometric equation

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