Research progress in lung parenchyma segmentation based on computed tomography / 生物医学工程学杂志

Lung diseases such as lung cancer and COVID-19 seriously endanger human health and life safety, so early screening and diagnosis are particularly important. computed tomography (CT) technology is one of the important ways to screen lung diseases, among which lung parenchyma segmentation based on CT images is the key step in screening lung diseases, and high-quality lung parenchyma segmentation can effectively improve the level of early diagnosis and treatment of lung diseases. Automatic, fast and accurate segmentation of lung parenchyma based on CT images can effectively compensate for the shortcomings of low efficiency and strong subjectivity of manual segmentation, and has become one of the research hotspots in this field. In this paper, the research progress in lung parenchyma segmentation is reviewed based on the related literatures published at domestic and abroad in recent years. The traditional machine learning methods and deep learning methods are compared and analyzed, and the research progress of improving the network structure of deep learning model is emphatically introduced. Some unsolved problems in lung parenchyma segmentation were discussed, and the development prospect was prospected, providing reference for researchers in related fields.

Overview and outlook of CT quantification technology for chronic obstructive pulmonary disease / 西安交通大学学报(医学版)

Chronic obstructive pulmonary disease (COPD) is a type of disease with diverse clinical manifestations and strong heterogeneity; thus early diagnosis is difficult. Patients at stable period often suffer from poor life quality. Frequent hospitalization induced by acute exacerbations has high social and economic burdens. COPD is predicted to be the third leading cause of death in the world by 2020 and the fifth leading cause of disability. At present, there is a lack of accurate quantitative technology. Our research team, in bearing of the Public Welfare Special Industry of National Health Commission "Diagnostic and Evaluation System of Respiratory Diseases Based on Digital Lung" and on the basis of CT quantitative technology, investigated the morphological changes of pulmonary parenchyma, bronchi and pulmonary vessels as well as their correlations. We provide an individualized, standardized and comprehensive evaluation for COPD patients. In this paper we also discuss the hot issues of COPD and point out the future research direction.

Congenital malformation of lung parenchyma: 15 years experience in a thoracic surgical unit.

Objective. To review the surgical management of congenital malformations of lung parenchyma in a thoracic surgery unit over a period of 15 years. Methods. We carried out a retrospective analysis of records of all patients who had surgery for congenital malformations of lung parenchyma between 1995 and 2010. Results. Forty-five patients underwent surgery for congenital lung lesions out of 3735 thoracotomies performed during the study period. The lesions included 29 lung sequestrations, 12 bronchogenic cysts, 3 congenital lobar emphysema and one congenital cystic adenomatoid malformation. Only 26 (26%) cases were diagnosed preoperatively. Twenty-eight (62.2%) patients underwent lobectomy, 5 (11.1%) patients had pneumonectomy, and 10 (22.2%) patients had removal of cyst while 2 (0.45%) patients had lung resection with repair of the oesophageal connection. No mortality was recorded. One patient had post-operative complication of oesophageal fistula which was successfully managed conservatively. The follow-up was between 8 months to 14 years. All patients were asymptomatic and had no physical limitations during the follow-up. Conclusions. Surgery is curative and produces good long-term result in patients with congenital malformations of lung parenchyma. It should be offered to patients as a therapeutic option where indicated and feasible.

Auto-segmentation method for lung parenchyma of CT images / 中国医学影像技术

Objective To establish a new automatic lung segmentation method in order to deal with the omission of pleural nodules and pulmonary vessels. Methods Lung parenchyma were extracted from chest CT images with the inversed operation of 2D region growing and connected area classification, then the contours and locating the contour points were traced with scan line searching. Finally, the parameters of lung contour points were analyzed to locate the contours distorted by nodules, and curve spline was used to correct distorted contours. Results The experimental results of many sets of CT images verified that the technique proposed was effective. The comparison with other contour correction algorithm verified that line searching contour correction was superior. Conclusion The proposed algorithm includes tumors in the segment results, and confirms the integrality, veracity, real-time quality of this auto-segmentation method.

The Objective Measurement of the Lung Parenchyma Motion for Planning Target Volume Delineation / 대한치료방사선과학회지

PURPOSE: To quantify the movement of lung parenchyma for ICRU 50 Planning Target Volume (PTV) delineation of the lung region. MATERIALS AND METHODS: Fluoroscopic observations and measurements are performed on 10 patients with chest region cancer who have normal pulmonary functions. We have divided the lung region into 12 parts for the right lung, 10 parts for the left lung and four to five points of lung parenchyma were selected for anatomical analysis points. Fluoroscopic images are sent to a computer and then movements are measured. RESULTS: Both lower lobes showed the longest longitudinal movements because of breathing (average 14.1mm, maximum 22.1mm), while antero- posterior displacement showed the smallest value. Lateral movements of the lung parenchyma averaged 6.6mm, and the maximum value was 9.1mm. (both hilar regions showed maximum values because of cardiac motion) CONCLUSION: We could quantify the lung movements by measuring parenchyma displacements. The movements of both upper lobes were less than those of the middle and upper lobes in longitudinal and transverse movements. Optimal margins can be selected for PTV delineation using these results.

The experimental research of R-Salbutamol on inhibiting the contraction of isolated tracheal smooth muscle in guinea-pig / 中国药理学通报

Aim To evaluate the effects of R-Salbutamol(R-Sal)on the contraction of isolated tracheal strips and lung parenchyma strips in guinea-pig,induced by Histamine(His).Methods Tracheal strips and lung parenchyma strips of guinea-pig in vitro were prepared,and the dilatory effect on shrinkage reaction of isolating specimens induced by His were measured before or after the administration of R-Sal in doses of 10-8,10-7,10-6 mol?L-1,with fix-doses pharmacology methods.The inhibitory effect was compared with that of Sal(10-6 mol?L-1).Results His could induce the contraction of isolated strips in guinea-pig in a dose-dependent manner,and R-Sal could significantly inhibit this shrinkage of lung parenchyma induced by His.in a dose-dependent manner.R-Sal was much more efficient than Sal(P