Analysis of equine scintigraphical lung images

A method is proposed (1) to create inhalation to perfusion ratio (I/Q) images from equine lung scintiscans and (2) to analyse these I/Q images. This method was applied to five healthy horses in order to establish reference ranges of I/Q distribution pattern. Computed I/Q images were divided in three regions based on the activity due to the inhalation (I) versus perfusion (Q) procedure. For each region a regional mismatching factor (Iri), i.e. the I/Q of the region, and an intraregional mismatching factor (Lri), which expresses the variability of pixels' I/Q within the region, were calculated. The Per(Ri) and Cen(Ri), which are the percentage of pixels in the parenchymal and in the central parts of the lung belonging to the region, were also computed. Results of this analysis showed a good match between I and Q distribution pattern.