Lung vascular changes as biomarkers of severity in systemic sclerosis-associated interstitial lung disease.

OBJECTIVES: It has recently become possible to assess lung vascular and parenchymal changes quantitatively in thoracic CT images using automated software tools. We investigated the vessel parameters of patients with SSc, quantified by CT imaging, and correlated them with interstitial lung disease (ILD) features. METHODS: SSc patients undergoing standard of care pulmonary function testing and CT evaluation were retrospectively evaluated. CT images were analysed for ILD patterns and total pulmonary vascular volume (PVV) extents with Imbio lung texture analysis. Vascular analysis (volumes, numbers and densities of vessels, separating arteries and veins) was performed with an in-house developed software. A threshold of 5% ILD extent was chosen to define the presence of ILD, and commonly used cut-offs of lung function were adopted. RESULTS: A total of 79 patients [52 women, 40 ILD, mean age 56.2 (s.d. 14.2) years, total ILD extent 9.5 (10.7)%, PVV/lung volume % 2.8%] were enrolled. Vascular parameters for total and separated PVV significantly correlated with functional parameters and ILD pattern extents. SSc-associated ILD (SSc-ILD) patients presented with an increased number and volume of arterial vessels, in particular those between 2 and 4 mm of diameter, and with a higher density of arteries and veins of <6 mm in diameter. Considering radiological and functional criteria concomitantly, as well as the descriptive trends from the longitudinal evaluations, the normalized PVVs, vessel numbers and densities increased progressively with the increase/worsening of ILD extent and functional impairment. CONCLUSION: In SSc patients CT vessel parameters increase in parallel with ILD extent and functional impairment, and may represent a biomarker of SSc-ILD severity.

Surgical treatment of giant bullae on the background of cystic lesion and vascular malformation. Case report.

Bullae formation on a cystic background is still not described thoroughly. This clinical case aims to improve this situation and describes the combination of multiple cysts with vascular malformation, giant bullae (2/3 of the left hemithorax and 1/2 of the right hemithorax) with suppuration in a 50-year-old smoker. Before surgery, treatment for chronic obstructive lung disease (COPD) was administered without a positive outcome. Bullectomy was subsequently conducted and histopathological data revealed vascular malformation causing microinfarctions in pulmonary parenchyma, cystic degeneration and tuberculosis. Although it became possible to establish a final diagnosis due to histology, the need for surgical treatment was clear from clinical and x-ray evidence. Such instances as the one presented in this case report should assist with improving our knowledge about bullae in combination with cysts in the lungs because they provide additional context in a clinical setting.

Comparing algorithms for automated vessel segmentation in computed tomography scans of the lung: the VESSEL12 study.

The VESSEL12 (VESsel SEgmentation in the Lung) challenge objectively compares the performance of different algorithms to identify vessels in thoracic computed tomography (CT) scans. Vessel segmentation is fundamental in computer aided processing of data generated by 3D imaging modalities. As manual vessel segmentation is prohibitively time consuming, any real world application requires some form of automation. Several approaches exist for automated vessel segmentation, but judging their relative merits is difficult due to a lack of standardized evaluation. We present an annotated reference dataset containing 20 CT scans and propose nine categories to perform a comprehensive evaluation of vessel segmentation algorithms from both academia and industry. Twenty algorithms participated in the VESSEL12 challenge, held at International Symposium on Biomedical Imaging (ISBI) 2012. All results have been published at the VESSEL12 website http://vessel12.grand-challenge.org. The challenge remains ongoing and open to new participants. Our three contributions are: (1) an annotated reference dataset available online for evaluation of new algorithms; (2) a quantitative scoring system for objective comparison of algorithms; and (3) performance analysis of the strengths and weaknesses of the various vessel segmentation methods in the presence of various lung diseases.

A compartment model of alveolar-capillary oxygen diffusion with ventilation-perfusion gradient and dynamics of air transport through the respiratory tract.

This paper presents a model of alveolar-capillary oxygen diffusion with dynamics of air transport through the respiratory tract. For this purpose electrical model representing the respiratory tract mechanics and differential equations representing oxygen membrane diffusion are combined. Relevant thermodynamic relations describing the mass of oxygen transported into the human body are proposed as the connection between these models, as well as the influence of ventilation-perfusion mismatch on the oxygen diffusion. The model is verified based on simulation results of varying exercise intensities and statistical calculations of the results obtained during various clinical trials. The benefit of the approach proposed is its application in simulation-based research aimed to generate quantitative data of normal and pathological conditions. Based on the model presented, taking into account many essential physiological processes and air transport dynamics, comprehensive and combined studies of the respiratory efficiency can be performed. The impact of physical exercise, precise changes in respiratory tract mechanics and alterations in breathing pattern can be analyzed together with the impact of various changes in alveolar-capillary oxygen diffusion. This may be useful in simulation of effects of many severe medical conditions and increased activity level.

Maternal Nicotine Induces Collagen Type IV Changes in the Mice Lung Parenchyma and its Vessels.

BACKGROUND: One of the undesirable effects of maternal nicotine exposure during pregnancy is pulmonary hypertension. Since nicotine binds to its receptors on pulmonary vessels the hypothesis of this research was the possible structural changes that nicotine may cause on newborn vessels. MATERIALS AND METHODS: Twenty-four female BALB/c mice were mated and finding vaginal plug was assumed as day zero of pregnancy. Pregnant mice were divided into 2 experimental and 2 control groups. Experimental group 1 received 3 mg/kg nicotine intraperitoneally from day 5 of gestation until the last day of pregnancy. Experimental group 2 received the same amount of nicotine during the same gestational days as well as the first 2 weeks after birth (lactation). The control groups received the same volume of normal saline during the same periods. At the end of exposure times, all the newborns (experimental and control) were anesthetized, their lungs were removed and immunohistochemical studies were carried out for tracing collagen. RESULTS: Our findings indicated that collagen reaction in the bronchial basement membrane (BBM) and extracellular matrix (ECM) of the lung parenchyma in experimental groups increased significantly compared to the control groups but these changes were not observed in BM of lung vessels in the experimental groups. CONCLUSION: These data indicate that nicotine exposure during pregnancy does not cause a significant change in collagen type IV in BM of lung vessels. But this does not mean that other types of collagen fibers do not indicate change because the wall thickness of pulmonary vessels in experimental groups increased significantly compared to the control groups.