publications by Ehsan Samei.


Papers Published

  1. Li, X; Samei, E, Comparison of patient size-based methods for estimating quantum noise in CT images of the lung., Med Phys, vol. 36 no. 2 (February, 2009), pp. 541-546 [19291993], [doi] .
    (last updated on 2024/10/31)

    Abstract:
    The authors explored four methods for estimating quantum noise in CT images of the lung, each based on a different definition of patient size (water-equivalent diameter) and the relationship between noise and diameter determined in water phantoms. The accuracies of the four methods were evaluated using an image-subtraction method as a gold standard. Noise estimates based on patient sizes derived from chest area, water-equivalent area, non-lung area, and water-equivalent path length had maximum errors of 229%, 93%, 34%, and 57%, respectively. Considering the magnitude of noise variation across the lung volume (approximately 30%), noise estimate based on non-lung area was reasonably accurate.

    Keywords:
    Body Size* • Humans • Image Processing, Computer-Assisted • Lung • Phantoms, Imaging • Tomography, X-Ray Computed • Water • methods* • physiology* • radiography* • standards