Open DCM File
The DCM extension files present, up to now, two applications of a different nature, namely:
DICOM
A DCM extension file is an image created by Digital Imaging and Communications in Medicine in its proprietary format.
DCM contains an image such as an MRI, ultrasound or CT scan, and can also store patient identification data to link the image to a specific person.
The DCM format was developed by the NEMA (National Electrical Manufacturers Association) for the exchange and display of medical images such as CT scans, MRIs, and ultrasound images.
DiskCatalogMaker
In this section, a DCM file is a catalog file used by DiskCatalogMaker, a file organizing and cataloging program for the Mac.
The DCM contains a database of files stored on multiple disks that are indexed and searchable by filename and other attributes.
As a final note, DCM files can also be saved as DCMF files, which are more common anyway.