Issue with overlaying medical images using transparency

Changing image transparency seems simple enough, but when I try to do this to superimpose my PET and MR imaging data, I don't get good results. First image shows what I have now and second shows an example of correctly superimposed results done manually.

Would love some help with this issue and have included my code and the variables:

figure
for n = 1:10
    subplot(2,5,n)
    MRtr = imshow(Ven(1:156,1:156,n),[]);
    hold on
    PTtr = imshow(interpolatedPET(1:156,1:156,n)',[],Colormap=hot);
    PTtr.AlphaData = 0.5;
end

Answer 1

[Taylor]

You could use imfuse.

load workspaceoverlay.mat
figure
for n = 1:10
    subplot(2,5,n)
    % MRtr = imshow(Ven(1:156,1:156,n),[]);
    % hold on
    % PTtr = imshow(interpolatedPET(1:156,1:156,n)',[],Colormap=hot);
    % PTtr.AlphaData = 0.5;
    c = imfuse(Ven(1:156,1:156,n), interpolatedPET(1:156,1:156,n)');
    imshow(c)
end

[Swathi]

Thanks, is there any way to do this while preserving the original images' colors though?