Quantitative analysis of airway abnormalities in CT

A coupled surface graph cut algorithm for airway wall segmentation from Computed Tomography (CT) images is presented. Using cost functions that highlight both inner and outer wall borders, the method combines the search for both borders into one graph cut. The proposed method is evaluated on 173 manually segmented images extracted from 15 different subjects and shown to give accurate results, with 37% less errors than the Full Width at Half Maximum (FWHM) algorithm and 62% less than a similar graph cut method without coupled surfaces. Common measures of airway wall thickness such as the Interior Area (IA) and Wall Area percentage (WA%) was measured by the proposed method on a total of 723 CT scans from a lung cancer screening study. These measures were significantly different for participants with Chronic Obstructive Pulmonary Disease (COPD) compared to asymptomatic participants. Furthermore, reproducibility was good as confirmed by repeat scans and the measures correlated well with the outcomes of pulmonary function tests, demonstrating the use of the algorithm as a COPD diagnostic tool. Additionally, a new measure of airway wall thickness is proposed, Normalized Wall Intensity Sum (NWIS). NWIS is shown to correlate better with lung function test values and to be more reproducible than previous measures IA, WA% and airway wall thickness at a lumen perimeter of 10 mm (PI10)

Implementation and organization of lung cancer screening

CT screening for lung cancer is now being implemented in the US and China on a widespread national scale but not in Europe so far. The review gives a status for the implementation process and the hurdles to overcome in the future. It also describes the guidelines and requirements for the structure and components of high quality CT screening programs. These are essential in order to achieve a successful program with the fewest possible harms and a possible mortality benefit like that documented in the American National Lung Screening Trial (NLST). In addition the importance of continued research in CT screening methods is described and discussed with focus on the great potential to further improve this method in the future for the benefit of patients and society

Smoking cessation and lung cancer screening

Smoking behavior may have a substantial influence on the overall effect of lung cancer screening. Non-randomized studies of smoking behavior during screening have indicated that computer tomography (CT) screening induces smoking cessation. Randomized studies have further elaborated that this effect has to do with participation in screening alone and not dependent on the CT scan. Participants in both CT and control arm in randomized screening trials had higher smoking abstinence rate compared to that of the general population. A positive screening test seems to further promote smoking cessation and decrease smoking relapse rate. Also low smoking dependency and high motivation to quit smoking at baseline predicted smoking abstinence in screening trials. Lung cancer screening therefore seems to be a teachable moment for smoking cessation. Targeted smoking cessation counselling should be an integrated part of future lung cancer screening trials

Low diffusion capacity of the lung predicts pneumothorax and chest drainage after CT-guided lung biopsy

Abstract Objectives Complications after CT-guided lung biopsy is a burden both for the individual patient and for the overall healthcare. Pneumothorax is the most common complication. This study determined the association between lung function tests and pneumothorax and chest drainage following CT-guided lung biopsy in consecutive patients in a large university hospital. Results We prospectively registered 875 biopsy procedures from 786 patients in one institution from January 27th 2012 to March 1st 2017 and recorded complications including pneumothorax with or without chest drainage. Lung function data from 637 patients undergoing 710 of the procedures were available. The association of lung function measures with pneumothorax with or without chest drainage was assessed using multivariable logistic regression analyses. Diffusion capacity for carbon monoxide (DLCO) below 4.70 mmol/min/kPa was associated with increased occurrence of pneumothorax and chest drainage after CT guided lung biopsy. We found no association between FEV1, RV and occurrence of pneumothorax and chest drainage. We found low DLCO to be a risk factor of pneumothorax and chest drainage after CT-guided lung biopsy. This should be taken into account in planning and performing the procedure