A comparison of image registration techniques for the correlation of radiolabelled antibody distribution with tumour morphology

Image registration is a powerful tool for correlating functional images wit h images of anatomical structure. This facilitates more accurate quantitati on of regional radiopharmaceutical uptake. Similarly, registration of image s of radiolabelled antibody distribution, in tissue sections, with the equi valent histological images allows the comparison and measurement of radioph armaceutical distribution with morphological structure. The images used wer e obtained by storage phosphor plate technology, for the radiopharmaceutica l distribution, and by digitization of the stained histological sections. H ere we compare four fully automatic registration techniques and one manual technique in terms of their spatial accuracy. We have found that there was no difference in accuracy between cross-correlation, minimization of varian ce and mutual information. These techniques were more accurate than princip al axes and the manual technique. However, minimization of variance and mut ual information were more time-consuming than the other methods. Consequent ly, cross-correlation is the method of choice for automatic registration of large numbers of these image pairs.