DI Repository

Diagnostic Imaging Repository

DIRs Contain Files Used in Diagnosis and Treatment

A diagnostic imaging repository (DIR) stores X-ray, MRI, CT, ultrasound, and nuclear medicine image and text report files for the connected hospitals and independent health facilities in its respective region.

With a patient’s consent, hospitals and independent health facilities upload copies of DI exams to the DIR. When a patient requires medical services, an authorized health service provider may access those DI exams to assist in diagnosis and treatment.

With fast, reliable, secure, and centralized access to diagnostic images and reports, an authorized health service provider has the ability to make decisions based on a patient’s health history (i.e., the longitudinal patient record) instead of only the current DI study.


Prospective parents watching an ultrasound







Doctor reviewing tablet in patient room




DIR Facts

  • All Canadian provinces have at least one DIR

  • Ontario has four regional DIRs

  • All Ontario acute care hospitals connect to a DIR

How a DIR Works

Hospitals and independent health facilities create diagnostic image files and store them electronically in a local Picture Archiving and Communication System (PACS), a Hospital Information System (HIS), or an Electronic Medical Record (EMR). A radiologist reviews the images, writes, and approves the DI report for patient diagnosis and treatment and for future use by other authorized health service providers when required.

Local DI systems link securely to the HDIRS-East or the HDIRS-West (formerly known as the GTA West DIR) repository, both of which are sophisticated computer systems that facilitate the controlled sharing and viewing of diagnostic imaging studies. Periodically (e.g., every day or multiple times per day) patient files get transferred to the repository. The repository stores DI image and text files as well as metadata associated with those files, such as the date of the exam, the originating hospital, who has accessed the exam, health number, and when it was last updated.

Even though DI exams may stem from many different software and hardware configurations, authorized health service providers can use either their own local PACS or a single web-based viewer to log in and view relevant patient information.

Patient Privacy

HDIRS enables hospitals and independent health facilities (IHFs) to share personal health information to support diagnosis, treatment, and care.

HDIRS is a health information network provider (HINP) that provides services to hospitals and IHFs, not to patients directly.

Getting your consent to collect, use, and disclose your diagnostic images is the responsibility of the hospital or IHF that captures, accesses, and shares your DI studies.

If you want to withdraw your consent for your images and related reports to be accessed or shared, you must contact the hospital or health facility that created your diagnostic images.


Operating room with ultrasound on screen







Operating room with brain images on screen



Larry Nijmeh BSc MD CCFP (EM) FCFP

Lakeridge Health and Scarborough and Rouge Hospital

HDIRS has been great for patient care and, in my own experience in the Emergency Department (ED), has enabled me to avoid ordering unnecessary repeat imaging studies. Having this access to historical studies is invaluable in the ED.