Define 2 plotted lines in an image as variables inside a function in Matlab?

Function [Yupper, Ylower] = Segmentation(A)
    A=imread('g16.BMP');
    AR=A(:,:,1);
    [rows, columns] = size(AR);
    avgs = mean(AR(50:165,:), 2);
    avgs2 = mean(AR(165:315,:), 2);
    [~,ind]= max(abs(diff(avgs)));
    [~,ind2]= max(abs(diff(avgs2)));
    figure, image(AR,'CDataMapping','scaled'); colormap('gray'); hold on;
    Yupper=plot([1 size(AR,2)], [ind+50 ind+50], 'r', 'LineWidth', 2);
    Ylower=plot([1 size(AR,2)], [ind2+165 ind2+165], 'g', 'LineWidth', 2);
end

Above is code used to segment grey scale images based on large instensity changes,I'm looking to declare the 2 plotted lines as variables so I can carry out future processing. However, If I type in whos , the lines appear as follows in the table;

YL               1x1                     112  matlab.graphics.chart.primitive.Line              
YU               1x1                     112  matlab.graphics.chart.primitive.Line

if I remove the the plot commands I receive errors associated with brackets etc and if I manipulate the code any further it seems to mess up the correctly plotted data, can anyone help?