CT-based Biomarker Provides Unique Signature for Diagnosis of COPD Phenotypes and Disease Progression

1] Department of Radiology, University of Michigan, Ann Arbor, Michigan, USA. [2] Center for Molecular Imaging, University of Michigan, Ann Arbor, Michigan, USA.
Nature medicine (Impact Factor: 28.05). 10/2012; 18(11). DOI: 10.1038/nm.2971
Source: PubMed

ABSTRACT Chronic obstructive pulmonary disease (COPD) is increasingly being recognized as a highly heterogeneous disorder, composed of varying pathobiology. Accurate detection of COPD subtypes by image biomarkers is urgently needed to enable individualized treatment, thus improving patient outcome. We adapted the parametric response map (PRM), a voxel-wise image analysis technique, for assessing COPD phenotype. We analyzed whole-lung computed tomography (CT) scans acquired at inspiration and expiration of 194 individuals with COPD from the COPDGene study. PRM identified the extent of functional small airways disease (fSAD) and emphysema as well as provided CT-based evidence that supports the concept that fSAD precedes emphysema with increasing COPD severity. PRM is a versatile imaging biomarker capable of diagnosing disease extent and phenotype while providing detailed spatial information of disease distribution and location. PRM's ability to differentiate between specific COPD phenotypes will allow for more accurate diagnosis of individual patients, complementing standard clinical techniques.

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Available from: Meilan K Han, Aug 21, 2015
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    • "The impact of alterations during disease, such as airway narrowing or changes in tissue properties, on regional ventilation and tissue stresses are not well understood. For example, one hypothesis is that airway disease may precede emphysema [12]. The computational lung model could be applied to investigate the impact of airway narrowing and tissue stiffness during obstructive lung diseases on tissue stresses, alveoli pressure and ventilation. "
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    • "Applications in medical imaging range from motion compensation to intra-operative fusion of different modalities. In particular, non-linear registration methods are able to capture complex deformations with high accuracy , enabling advanced diagnosis and treatment [2]. Many of these methods, however, exhibit long processing times or require special hardware such as GPUs. "
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    IEEE International Symposium on Biomedical Imaging: From Nano to Macro, Beijing, China; 04/2014
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    • "In the following, %emph MF refers to the %emph measure obtained with the presented HMMF model. %emph −950 represents the standard %emph using a threshold of −950 HU, which is commonly used in clinical studies [29], [30], and PD 15 is the 15 th percentile density. "
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