Assuming you have the Image Processing Toolbox, use dicomread to read the data from file, and then save to save the data to a mat file. Something like
inputFilename = 'myDicomFile.dcm';
inputFolder = '/Users/somePath/dicomFiles';
% read the file
[X,map] = dicomread(fullfile(inputFolder,inputFilename));
% now write to a mat file
outputFilename = 'myMatFile.mat';
outputFolder = '/Users/somePath/matFiles';
save(fullfile(outputFolder,outputFilename),'X','map');
If you have several files to read and write, you can choose an appropriate outputFilename for each.
