DICOM® is a Standard for communication of medical imaging information.  Selected highlights of its history are shown below:


In the beginning... it was very difficult for anyone other than manufacturers of computed tomography (CT) or magnetic resonance imaging (MRI) devices to decode the images that the machines generated, or to print them.


The American College of Radiology (ACR) and the National Electrical Manufacturers Association (NEMA) joined forces and formed a Standards committee to meet the combined needs of radiologists, physicists and equipment vendors.


Their first Standard covering point-to-point image communication, ACR-NEMA 300, was released. The specified image transmission used a dedicated 16-bit parallel interface.


The second version of ACR-NEMA 300 was released, gaining increasing acceptance among vendors.


The first demonstration of ACR-NEMA V2.0 occured at Georgetown University in May 1990, and later that year at the annual meeting of the Radiological Society of North America (RSNA).


The third version of the Standard evolved to use local area networks like Ethernet by layering the medical image protocols on top of general networking protocols (TCP/IP). The name was changed to DICOM (Digital Imaging and COmmunications in Medicine), and published as NEMA Standard PS3.


Ultrasound, X-ray angiography, and nuclear medicine protocols added to DICOM, supporting the needs of cardiology imaging.
CD-based image exchange via allowed off-line transfer of imaging studies.
The DICOM Standards Committee was reorganized to formally represent all medical specialties that use imaging, not just radiology, including the American College of Cardiology (ACC).


Workflow management in the imaging department was Standardized as DICOM added the Modality Worklist service.


Radiation therapy information objects were added.


Endoscopy and dermatology became part of the Standard through the addition of Visible Light objects.
Consistent presentation of image annotations across display systems are enabled with the first Presentation State information objects.


Structured data, analytic results and clinical observations made in the imaging environment were Standardized with Structured Reporting (SR), extending DICOM beyond just images.
Internet security mechanisms were added through secure communication profiles for the DICOM protocol.


Mammography CAD (Computer Aided Detection) SR added for the results of automated image analysis.
Media security mechanisms defined.


Multi-frame enhanced image formats adopted to support the next generation of advanced MR and CT imaging techniques.
DVD media exchange added.


WADO (Web-access to DICOM objects) added to retrieve DICOM images over HTTP connections.
Dentistry and ophthalmology joined DICOM.
USB and Flash memory media exchange added.
Spatial registration supported for rigid registrations of imaging datasets.
MPEG2 encoding of video data supported.


Radiation Dose Structured Reports (RDSR) added for x-ray based imaging (including angiography, mammography, CR and DR) to support patient safety related data collection.
PDF document encapsulation in DICOM to manage documents associated with imaging studies.


Deformable spatial registration added to handle MR fields, atlases and other deformable cases.


Radiation Dose for CT (RDSR) added to RDSR.


Breast tomosynthesis ("3-D mammography") added.


3D ultrasound added.


Whole slide imaging added to support anatomic pathology imaging (specimen identification added in 2008).
Surgical planning information objects added.


Bluray media exchange added.


Second generation RESTful web services defined to retrieve, store and query DICOM images. The suite of web services is re-branded as DICOMweb™, and is aligned with the upcoming HL7 FHIR web services.


Radiopharmaceutical Radiation Dose Reporting (RRDSR) added.


Server-based Rendering added to WADO-RS, allowing web clients to request DICOM images and video be rendered into consumer media formats for simple display, e.g. in EHR portals.
Tractography Results storage added to support applications such as MR DTI in neurology.
Imaging report templates using the HL7 Clinical Document Architecture (CDA) added, aligning with requirements for CDA in the U.S. Meaningful Use of Electronic Health Record Systems regulations.
Wide-Field Ophthalmic Photography images added.
Brachytherapy Delivery Instruction objects added to support radiotherapy treatment delivery.
AVC/H.264 (MPEG4) video support added.


CT Protocol Storage added for both generic (non-patient-specific) protocols and actual performed protocols.
Adult Echo Measurement SR objects updated/simplified for improved compatibility with cardiac databases and data analytics.
HEVC/H.265 (MPEG4) video support added. Small Animal Acquisition Context headers added to support imaging in pre-clinical research.


Volumetric and Blending Presentation States added to manage 3D rendering of image sets and advanced multi-stage blending.
NCI AIM to DICOM SR transcoding defined to facilitate management of image markup for machine learning and other applications.
Patient Dose Estimate reports (P-RDSR) based on RDSR data for individual patients added.
Ophthalmic OCT angiography (OCT-A) imaging added.


3D Manufacturing - STL encapsulation added image-based medical 3D-printing workflows.
TLS ciphersuites updated to match current transaction security recommendations.
Contrast Injection SR added to track detailed power injector records for QA and clinical analysis.
Multi-Energy CT Image Storage added to provide Standard encodings of new dual-energy and spectral acquisition techniques for use by image displays and analysis packages.
Second Generation RT Prescriptions provides the basis for a series of upcoming 2nd Generation RT planning and delivery objects.


DICOMweb Redocumentation re-organizes Part 18 to provide a comprehensive view of all DICOM web services in a uniform structure oriented toward web implementers.
DICOMweb Thumbnails service added to provide study/series/image thumbnails to clients such as web apps.
Realtime Video Streaming (DICOM-RTV) added to support streaming medical video and audio over IP networks using the SMPTE ST 2110 protocol family and a profiled DICOM metadata stream.
Second Generation C-Arm RT introduces the RT Radiation Set and representation of C-Arm techniques.