CIRRUS Lung: an optimized workflow for quantitative image analysis of thoracic computed tomography and chest radiography for major pulmonary diseases: chronic obstructive pulmonary disease, lung cancer and tuberculosis
B. van Ginneken, E.M. van Rikxoort, S.J. Lafebre, C. Jacobs, M. Schmidt, J.-M. Kuhnigk, M. Prokop, C.M. Schaefer-Prokop, J. Charbonnier, L. Hogeweg, P. Maduskar, L. Gallardo-Estrella, R. Philipsen and B. Lassen
in: Annual Meeting of the Radiological Society of North America, 2013
BACKGROUND Lung diseases are among the most deadly disorders: chronic obstructive pulmonary disease (COPD), a devastating disease with 12 million people in the United States currently diagnosed, ranks #3 on the list of causes of death wordwide. Lung cancer, by far the most common and most deadly cancer in men and women worldwide, ranks #5. Tuberculosis (TB), despite the availability of a cheap and effective cure, ranks #10. Imaging is crucially important for early detection, diagnosis, follow-up, and treatment planning of COPD, lung cancer and TB. Chest radiography and computed tomography are the most important imaging modalities for the lung. METHODOLOGY/APPLICATION We present a flexible workstation for a quick and effective extraction of quantitative imaging parameters related to COPD, lung cancer and TB. The workstation loads an arbitrary number of CT and chest radiography studies of each subject simultaneously, allowing the user to instantly track the evolution of any lesion. Each CT scan is elastically registered to all prior CT scans of the same subject. Findings in prior scans have been automatically propagated and linked to findings in the current scan. All scans and processing results are preloaded in the background to ensure rapid reading. The CIRRUS Lung workstation has been developed jointly by the Diagnostic Image Analysis Group, Radboud University Nijmegen Medical Centre, Nijmegen The Netherlands, and Fraunhofer MEVIS, Bremen, Germany. It is based on the MeVisLab software platform. The workstation is available through research collaboration agreements and in active use in a variety of projects . CIRRUS Lung has a number of modes that will be demonstrated: 1) High throughput lung screening. Scan quality is automatically assessed; data with low quality, artifacts or underlying interstitial lung disease are flagged. High sensitivity computerized detection (CAD) of solid nodules and sub-solid nodules is included. High throughput reading with CAD as a first reader is supported. Each nodule is automatically characterized as solid, part-solid, non-solid, or benign (calcified lesions, perifissural lymph nodes). Volumetry, volume growth rate, mass and mass growth rate are automatically computed with advanced segmentation algorithms that have can handle sub-solid lesions and segment the solid core of part-solid nodules. Findings are summarized in a structured report. Follow-up recommendation according to Fleischner guidelines are included. 2) Clinical oncology work-up. This mode is similar to the screening mode, but includes completely automatic generation of RECIST workup. 3) Chest radiography lung screening. Chest radiographs can be annotated and viewed with various tools such as bone suppression and gray scale inversion. Computer-aided detection and interactive CAD reading are supported. 4) COPD quantification. Elastic registration between inspiration and expiration scans has been precomputed and allows for linked scrolling. Lungs, lobes, airways, fissures, and segments are automatically segmented for regional functional analysis. In case the user is not satisfied with the segmentation results, (s)he can quickly correct these with an intuitive interactive correction method. CT image standardization is included using a precomputed dedicated energy correction algorithm that makes quantifications less dependent on scan protocol (scanner model, kernel, iterative reconstruction). Once the segmentations have been approved, a range of quantifiable features can be visualized in the workstation: parenchyma features, airway features, and fissural completeness. Measurements are reported for both inspiration and expiration for the whole lung as well as per lobe and segment. Changes between inspiration and expiration are reported. After workup of a study of a COPD patient, a structured report is produced that contains screenshots, renderings, and all requested measurements. 5) TB Diagnostics. In this mode chest radiographs can be inspected and texture analysis that detects abnormalities consistent with TB can be inspected. A novel symmetry analysis is available to facilitate contralateral comparisons. Detection and quantification of costophrenic angle bluntness is included. Cavities can be semi-automatically segmented. DEMONSTRATION STRATEGY The exhibit will be accompanied by an informational poster that will highlight the key features and algorithmic concepts that underlie the automated analysis. Attendees will be able to gain hands-on experience with the workstation and read cases. For each reading mode, extensive example datasets are available. In particular, the completely processed LIDC/IDRI database, including all CT scans and chest radiographs, is available for inspection. REFERENCES AND PUBLICATIONS The algorithms presented in the showcase are based on over 20 different journal publications. These are listed on http://cirrus.diagnijmegen.nl.