//Open the DICOMDIR File
QString DICOMDIR_folder = "C:/Folder1/Folder2";
const char *fileName = "C:/Folder1/Folder2/DICOMDIR";
DcmDicomDir dicomdir(fileName);
//Retrieve root node
DcmDirectoryRecord *root = &dicomdir.getRootRecord();
//Prepare child elements
DcmDirectoryRecord *rootTest = new DcmDirectoryRecord(*root);
DcmDirectoryRecord *PatientRecord = NULL;
DcmDirectoryRecord *StudyRecord = NULL;
DcmDirectoryRecord *SeriesRecord = NULL;
DcmDirectoryRecord *image = NULL;
 
if(rootTest == NULL || rootTest->nextSub(PatientRecord) == NULL) 
    std::cout << "It looks like the selected file does not have the expected format." << std::endl;
else
{
    while ((PatientRecord = root->nextSub(PatientRecord)) != NULL)
    {
        while ((StudyRecord = PatientRecord->nextSub(StudyRecord)) != NULL)
        {
            while ((SeriesRecord = StudyRecord->nextSub(SeriesRecord)) != NULL)
            {
                while ((image = SeriesRecord->nextSub(image)) != NULL)
                {
                    const char *sName;
                    //Retrieve the file name
                    image->findAndGetString(DCM_ReferencedFileID, sName);
 
                    //If a file is selected
                    if(sName != "")
                    {
                      //sName is the path for the file from the DICOMDIR file
                      //You need to create the absolute path to use the DICOM file
                      
                      //Here you can do different tests (does the file exists ? for example)
                      
                      //Treat the dicom file
                    }
                }
            }
        }
    }
}