Measurement of Lung Density by Means of Quantitative CT Scanning

Background: The purpose of this study was to evaluate the quantitative diagnostic performance of computed tomography (CT) densitometry in pediatric bronchiolitis obliterans (BO) patients. Methods: A retrospective chart review was performed on 109 children under age 18 who underwent 3D chest CT from March 2019 to March 2021. We measured the mean lung density (MLD) and calculated the difference of MLD (MLDD) in expiratory and inspiratory phase, the expiratory to inspiratory ratio of mean lung density (E/I MLD), and the relative volume percentage of lung density at 50 HU intervals (E600 to E950). We calculated the sensitivity, specificity, and diagnostic accuracy of lung density indices for the diagnosis of BO. Results: A total of 81 patients, 51 BO patients and 30 controls, were included in this study (mean age: 12.7 vs 11.4 years). Expiratory (EXP) MLD, MLDD, E/I MLD, and E900 were all statistically significantly worse in the BO group. Multivariate logistic regression analysis showed that MLDD (odds ratio [OR] = 0.98, p < .001), E/I MLD (OR = 1.39, p < .001), and E850 (OR = 1.54, p = 0.003) were significant densitometry parameters for BO diagnosis. In ROC analysis, E900 (cut-off 1.4%; AUC = 0.920), E/I MLD (cut-off 0.87; AUC = 0.887), and MLDD (cut-off 109 HU; AUC = 0.867) showed high accuracy in diagnosis of BO. Conclusion: The quantification of lung density with chest CT complements the diagnosis by providing additional indications of expiratory airflow limitation in pediatric BO patients.

Download Full-text

A method to develop an in vitro osteoporosis model of porcine vertebrae: histological and biomechanical study

Journal of Neurosurgery Spine ◽

10.3171/2010.12.spine10453 ◽

2011 ◽

Vol 14 (6) ◽

pp. 789-798 ◽

Cited By ~ 13

Author(s):

Ching-yi Lee ◽

She-Hung Chan ◽

Hung-Yi Lai ◽

Shih-Tseng Lee

Keyword(s):

Lumbar Vertebrae ◽

Ct Scanning ◽

Biomechanical Study ◽

Mineral Density ◽

Solution Ph ◽

Quantitative Ct ◽

Spinal Implant ◽

Before And After

Object The porcine spine is widely used as an alternative to the human spine for both in vivo and in vitro spinal biomechanical studies because of the limited availability and high cost of human specimens. The aim of this study was to develop a reproducible in vitro osteoporotic vertebral model for spinal implant investigations. Methods Four mature domestic porcine lumbar spines (L1–5) were obtained. An in vitro decalcification method was used to decrease the mineral content of the porcine vertebrae, with Ca-chelating agents (0.5 M EDTA solution, pH 7.4) that altered the bone mineral density (BMD). Lumbar-spine area BMD was evaluated using dual-energy x-ray absorptiometry; spine volumetric BMD and spine geometry were assessed by central quantitative CT scanning to monitor the time it took the decalcification process to induce the WHO-defined standard of osteoporosis. Micro–computed topography provided information on the 3D microarchitecture of the lumbar vertebrae before and after decalcification with EDTA. Hematoxylin and eosin staining of lumbar vertebrae was performed. Both the control (5 specimens) and osteoporotic vertebrae (5 specimens) were biomechanically tested to measure compressive strength. Results The differences in area BMD measurements before and after the demineralizing processes were statistically significant (p < 0.001). The results of the compression test before and after the demineralizing processes were also statistically significant (p < 0.001). Conclusions The data imply that the acid demineralizing process may be useful for producing a vertebra that has some biomechanical properties that are consistent with osteoporosis in humans.

Download Full-text

Computerized tomography and pulmonary diffusing capacity in highly trained athletes after performing a triathlon

Journal of Applied Physiology ◽

10.1152/jappl.1995.79.4.1226 ◽

1995 ◽

Vol 79 (4) ◽

pp. 1226-1232 ◽

Cited By ~ 64

Author(s):

C. Caillaud ◽

O. Serre-Cousine ◽

F. Anselme ◽

X. Capdevilla ◽

C. Prefaut

Keyword(s):

Ct Scanning ◽

Breath Holding ◽

Diffusing Capacity ◽

Long Distance ◽

Alveolar Volume ◽

Lung Density ◽

Male Athletes ◽

Pulmonary Diffusing Capacity ◽

Before And After ◽

Long Distance Race

We investigated the computerized tomographies (CTs) of the thorax and the pulmonary diffusing capacity for CO (DLCO) in eight male athletes before and after a triathlon. DLCO and alveolar volume (VA) were simultaneously measured during 9 s of breath holding. The transfer coefficient (KCO = DLCO/VA) was then calculated. CT scanning was performed during breath holding with the subjects in the supine position. Scanner analysis was done by 1) counting the linear and polygonal opacities (index of interstitial fluid accumulation) and 2) calculating the physical mean lung density and the mean slice mass. Results showed a significant reduction in DLCO (44.9 +/- 2.3 vs. 42.9 +/- 1.7 ml.min-1.mmHg-1; P < 0.05) and KCO (6.0 +/- 0.3 vs. 5.6 +/- 0.3 ml.min-1.mmHg-1.l of VA-1; P < 0.05) after the triathlon and an increase in mean lung density (0.21 +/- 0.009 vs. 0.25 +/- 0.01 g/cm3; P < 0.0001). The number of polygonal and linear opacities increased after the race (P < 0.001). This study confirmed that DLCO and KCO decrease in elite athletes after a long-distance race and showed a concomitant increase in CT lung density and in the number of opacities.

Download Full-text

Quantitative CT Scanning Analysis of Pure Ground-Glass Opacity Nodules Predicts Further CT Scanning Change

CHEST Journal ◽

10.1378/chest.15-0034 ◽

2016 ◽

Vol 149 (1) ◽

pp. 180-191 ◽

Cited By ~ 36

Author(s):

So Hyeon Bak ◽

Ho Yun Lee ◽

Jae-Hun Kim ◽

Sang-Won Um ◽

O Jung Kwon ◽

...

Keyword(s):

Ground Glass Opacity ◽

Ct Scanning ◽

Ground Glass ◽

Quantitative Ct

Download Full-text

A comparison of CT lung voxel density analysis in a blast and non blast injured casualty.

Journal of the Royal Army Medical Corps ◽

10.1136/jramc-2018-000979 ◽

2018 ◽

Vol 165 (3) ◽

pp. 166-168

Author(s):

Sebastian Bourn ◽

T E Scott ◽

E J Hulse

Keyword(s):

Lung Injury ◽

Three Dimensional ◽

High Morbidity ◽

Quantitative Ct ◽

Lung Density ◽

Blast Exposure ◽

Blast Lung Injury ◽

Density Analysis ◽

Assisted Diagnosis ◽

Trauma Ct

IntroductionPrimary blast lung injury (PBLI) is a prominent feature in casualties following exposure to blast. PBLI carries high morbidity and mortality, but remains difficult to diagnose and quantify. Radiographic diagnosis of PBLI was historically made with the aid of plain radiographs; more recently, qualitative review of CT images has assisted diagnosis.MethodsWe report a novel way of measuring post-traumatic acute lung injury using CT lung density analysis in two casualties. One casualty presented following blast exposure with confirmed blast lung injury and the other presented following extremity injury without blast exposure. Three-dimensional lung maps of each casualty were produced from their original trauma CT scan. Analysis of the lung maps allowed quantitative radiological comparison exposing areas of reduced aeration of the patient’s lungs.Results45% of the blast-exposed lungs were non-aerated compared with 10% in the non-blast-exposed lungs.DiscussionIn these example cases quantitative CT lung density analysis allowed blast-injured lungs to be distinguished from non-blast-exposed lungs.

Download Full-text