77
views
0
recommends
+1 Recommend
0 collections
    0
    shares
      • Record: found
      • Abstract: found
      • Article: not found

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

      research-article

      Read this article at

      ScienceOpenPublisherPMC
      Bookmark
          There is no author summary for this article yet. Authors can add summaries to their articles on ScienceOpen to make them more accessible to a non-specialist audience.

          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 are 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 CT scans of 194 COPD individuals acquired at inspiration and expiration 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. PRMs ability to differentiate between specific COPD phenotypes will allow for more accurate diagnosis of individual patients complementing standard clinical techniques.

          Related collections

          Most cited references26

          • Record: found
          • Abstract: found
          • Article: not found

          Functional diffusion map: a noninvasive MRI biomarker for early stratification of clinical brain tumor response.

          Assessment of radiation and chemotherapy efficacy for brain cancer patients is traditionally accomplished by measuring changes in tumor size several months after therapy has been administered. The ability to use noninvasive imaging during the early stages of fractionated therapy to determine whether a particular treatment will be effective would provide an opportunity to optimize individual patient management and avoid unnecessary systemic toxicity, expense, and treatment delays. We investigated whether changes in the Brownian motion of water within tumor tissue as quantified by using diffusion MRI could be used as a biomarker for early prediction of treatment response in brain cancer patients. Twenty brain tumor patients were examined by standard and diffusion MRI before initiation of treatment. Additional images were acquired 3 weeks after initiation of chemo- and/or radiotherapy. Images were coregistered to pretreatment scans, and changes in tumor water diffusion values were calculated and displayed as a functional diffusion map (fDM) for correlation with clinical response. Of the 20 patients imaged during the course of therapy, 6 were classified as having a partial response, 6 as stable disease, and 8 as progressive disease. The fDMs were found to predict patient response at 3 weeks from the start of treatment, revealing that early changes in tumor diffusion values could be used as a prognostic indicator of subsequent volumetric tumor response. Overall, fDM analysis provided an early biomarker for predicting treatment response in brain tumor patients.
            Bookmark
            • Record: found
            • Abstract: found
            • Article: not found

            Comparison of computed density and macroscopic morphometry in pulmonary emphysema.

            High-resolution computed tomography (HRCT) scans were obtained at 1 cm intervals in 63 subjects referred for surgical resection of a cancer or for transplantation to find out whether the relative area of lung occupied by attenuation values lower than a threshold would be a measurement of macroscopic emphysema. Using a semiautomatic procedure, the relative areas occupied by attenuation values lower than eight thresholds ranging from -900 to -970 HU were calculated on the set of scans obtained through the lobe or the lung to be resected. The extent of emphysema was quantified by a computer-assisted method on horizontal paper-mounted lung sections obtained every 1 to 2 cm. The only level for which no statistically significant difference was found between the HRCT and the morphometric data was -950 HU. To determine the number of scans sufficient for an accurate quantification, we recalculated the relative area occupied by attenuation values lower than -950 HU on progressively fewer numbers of scans and investigated the departure from the results obtained with 1 cm intervals. Because of wide variations in this departure from patient to patient, a standard cannot be recommended as the optimal distance between scans.
              Bookmark
              • Record: found
              • Abstract: found
              • Article: not found

              Comparison of computed density and microscopic morphometry in pulmonary emphysema.

              The purpose of this prospective study was to verify whether the percentage area of lung occupied by lowest attenuation values on high-resolution computed tomography (HRCT) scans reflects microscopic emphysema and to compare this quantification with the information yielded by the most widely used pulmonary function tests (PFT). Preoperative HRCT scans were obtained with 1-cm intervals in 38 subjects. With a semiautomatic evaluation procedure, the percentage areas occupied by attenuation values inferior to thresholds ranging from -900 Hounsfield units (HU) to -970 HU were calculated for the lobe or lung to be resected. Emphysema was microscopically quantified by using a computer-based method, measuring the perimeters and interwall distances of alveoli and alveolar ducts. The strongest correlation was found for -950 HU. As a second step, we evaluated possible correlations between PFT and microscopic measurements. Finally, considering the microscopic measurements as a standard, we tried to investigate their relationships with each of the PFT and with the relative area occupied by attenuation values lower than -950 HU for both lungs. This revealed that the diffusing capacity for carbon monoxide associated with HRCT quantification is sufficient to predict microscopic measurements. We concluded that the percentage area of lung occupied by attenuation values lower than -950 HU is a valid index of pulmonary emphysema.
                Bookmark

                Author and article information

                Journal
                9502015
                8791
                Nat Med
                Nat. Med.
                Nature medicine
                1078-8956
                1546-170X
                1 June 2012
                07 October 2012
                November 2012
                01 May 2013
                : 18
                : 11
                : 1711-1715
                Affiliations
                [1 ]Department of Radiology, University of Michigan, Center for Molecular Imaging, Ann Arbor, Michigan 48109, USA
                [2 ]Department of Internal Medicine, University of Michigan, Center for Molecular Imaging, Ann Arbor, Michigan 48109, USA
                [3 ]Department of Biostatistics, University of Michigan, Center for Molecular Imaging, Ann Arbor, Michigan 48109, USA
                [4 ]Department of Radiation Oncology, University of Michigan, Center for Molecular Imaging, Ann Arbor, Michigan 48109, USA
                Author notes
                Corresponding Author: Brian D. Ross, Ph.D., Professor of Radiology, Center for Molecular Imaging, Biomedical Sciences Research Building, Room 2071, 109 Zina Pitcher Place, University of Michigan, Ann Arbor, MI 48109-2200, Phone: (734)-763-2099, Fax: (734)-763-5447, bdross@ 123456umich.edu
                Article
                NIHMS381684
                10.1038/nm.2971
                3493851
                23042237
                2a3c2497-ecd7-4f49-adce-d0f65dfae547

                Users may view, print, copy, download and text and data- mine the content in such documents, for the purposes of academic research, subject always to the full Conditions of use: http://www.nature.com/authors/editorial_policies/license.html#terms

                History
                Funding
                Funded by: National Heart, Lung, and Blood Institute : NHLBI
                Award ID: U01 HL089856 || HL
                Funded by: National Institute of Biomedical Imaging and Bioengineering : NIBIB
                Award ID: T32 EB005172 || EB
                Funded by: National Cancer Institute : NCI
                Award ID: P50 CA093990 || CA
                Categories
                Article

                Medicine
                Medicine

                Comments

                Comment on this article