dicomwrite function and grayscale image

Hi guys, I got a .mat image file in MATLAB and transferred it to .dcm file by dicomwrite function. this image is rewritten to a grayscale file. when I use dicomread function to get back the image, all the pixel number has changed. I don't know how to get back to original image. dose anybody have the solution? thanks.

the process I did is

dicomwrite(I,'DICOM.dcm','WritePrivate',true,'ObjectType','CT Image Storage');
X=dicomread('DICOM.dcm');
Y=dicominfo('DICOM.dcm');

also I dont find the RescaleSlope and RescaleIntercept data in Y.

thanks. Julien

Answer 1

[Image Analyst]

What was the data type of I ?

[julien zhu]

I is a data matrix, class double and it can be illustrated by imshow(I,[])