1. An apparatus for organizing two-dimensional or thin three-dimensional axial slice images acquired by a computed tomography scanner at different times and at different positions along a scanner axis, the apparatus comprising: a respiratory marker including an elongated detectable portion operatively coupled with respiration of a human imaging subject such that the elongated detectable portion moves with the respiration, the elongated detectable portion to intersecting the two-dimensional or thin three-dimensional axial slice images acquired at different times and at different positions along the scanner axis and being detectable as a marker feature in the two-dimensional or thin three-dimensional axial slice images; and a marker position finder configured to determine positions of the marker features in the two-dimensional or thin three-dimensional axial slice images.