write

Import a DICOM file into the workspace. The DICOM file is part of a data set containing three CT volumes. The size of the entire data set is approximately 81 MB. Download the data set from the MathWorks® website, then unzip the folder.

zipFile = matlab.internal.examples.downloadSupportFile("medical","MedicalVolumeDICOMData.zip");
filepath = fileparts(zipFile);
unzip(zipFile,filepath)
datapath = fullfile(filepath,"MedicalVolumeDICOMData/LungCT01/CT000000.dcm");
dFile = dicomFile(datapath);

Get the raw pixel data of the DICOM file by specifying rescale as false.

pixelData = getPixelData(dFile,rescale=false);

Filter the pixel data. The filtered pixel data is the pixel data for the new DICOM file. Making the modifications on the raw pixel data instead of the rescaled pixel data ensures that the pixel data is not rescaled repeatedly while getting pixel data from the new DICOM file.

filteredPixelData = imgaussfilt(pixelData,2);

Visualize and compare the original and filtered pixel data.

figure
imshow([pixelData filteredPixelData],[])

Create a study description for the new DICOM file. Then, create a structure metadata with a StudyDescription field that contains your new study description.

newStudyDescription = 'CT CARDIAC CALCIUM SCORING FILTERED';
metadata = struct("StudyDescription",newStudyDescription)

metadata = struct with fields:
    StudyDescription: 'CT CARDIAC CALCIUM SCORING FILTERED'

Create a modified copy of the CT image DICOM file, replacing its pixel data with the filtered pixel data and its metadata with the structure containing your new study description.

write(dFile,"CT00000_filtered.dcm",filteredPixelData,metadata)