Patent ID: 8666139

Claim:
A method of producing a ventilation image, comprising: receiving m image data sets, wherein at least a portion of a patient's lung is represented by the m image data sets; determining an initial volume, V, for each local volume element of a plurality of local volume elements based on one or more of the m image data sets; calculating an n th local volume change, (ΔV) n , between an n th image data set and an (n+1) th image data set for each local volume element, for n=1, 2, . . . m−1; calculating (ΔV) sum /V for each local volume element, where (ΔV) sum is the sum (ΔV) 1 +(ΔV) 2 + . . . +(ΔV) m− 1; producing a ventilation image having a plurality of ventilation image voxels, wherein each ventilation image voxel of the plurality of ventilation image voxels corresponds to one or more local volume element of the plurality of local volume elements and is represented by an indicator corresponding to the one or more (ΔV) sum /V value for the corresponding one or more local volume element.