Writing

Medical Imaging·12 March 2026

Understanding DICOM: More Than a Medical Image File

DICOM is often introduced as a file format. In reality, it defines an ecosystem for storing, exchanging, identifying and managing medical imaging information.

DICOM is often introduced as a file format.

In reality, it defines an ecosystem for storing, exchanging, identifying and managing medical imaging information — from modality communication to long-term archives and diagnostic viewers.

Beyond the .dcm file

A DICOM object carries both pixel data and a rich set of metadata tags: patient identifiers, study and series UIDs, modality type, acquisition parameters, and more.

That metadata is what makes imaging systems interoperable. Without it, a PACS would simply be a folder of images.

The networking model

DICOM networking defines services such as:

  • C-STORE — send images to an archive
  • C-FIND — query for studies and series
  • C-MOVE — retrieve studies between systems
  • MWL — modality worklist for scheduled procedures

Rendering diagram…

DICOMweb

Modern imaging platforms increasingly expose imaging services over HTTP using DICOMweb:

ServicePurpose
QIDO-RSQuery studies, series, instances
WADO-RSRetrieve imaging objects
STOW-RSStore imaging objects

This is especially useful when building web-based viewers and cloud-native imaging infrastructure.

Why this matters in Africa

Building imaging infrastructure for environments with constrained connectivity and mixed vendor fleets means treating DICOM as a systems protocol, not just a file type.

Understanding associations, SOP classes, and worklist behaviour is foundational for platforms like PACS and RIS.