PACS archiving

What is a PACS?

PACS stands for "Picture Archiving and Communication System" and is a digital system for processing, managing, and archiving medical images and data - similar to a database and in which all medical images are stored. Every medical image taken within a hospital is automatically stored on a PACS server.

Images are captured and stored from diagnostic medical devices, such as X-ray, sonography, CT, MRI, or endoscopy. Meanwhile, PACS is growing into an application for the entire hospital. Other departments such as cardiology, neurology, radiotherapy, and also pathology want to take advantage of digital image data management and store their image data in PACS.

The data is stored in a short-term memory. Downstream, the data is stored long-term in a digital archive to ensure unchanged retention.

The long-term archive must meet high requirements. Legally-compliant archiving is a central function of the PACS archive. Due to retention periods of several decades, the data volumes in the long-term archive grow enormously. At the same time, this data must be accessible at all times by physicians at different locations and protected against changes or loss in keeping with legal regulations.

The technical advancement of imaging procedures simplifies diagnostics for physicians through high-quality images, but at the same time leads to large amounts of data and rapidly growing storage requirements.

Whereas a few years ago digital images were primarily created in radiology with the help of X-ray machines and CT scanners, the number of medical devices which send data to a long-term archive has now increased dramatically.

Due to technological advances, these devices are generating increasingly high-resolution images which allow for better reporting. As a result, the file sizes generated are also increasing. Whereas in the past only a few megabytes had to be archived per examination, today several gigabytes per examination are possible with high-resolution and moving image data. A modern multi-line computer tomograph, for example, produces up to 4000 individual images per examination.

These data volumes are due to medical image data such as CT scans, MRIs, ECG, ultrasound, and X-ray images and are generated in radiology, oncology, or pathology and stored in PACS applications.

This trend ensures that the storage requirements for PACS archiving of medical image data in many hospitals have suddenly exploded in recent years.

Not only is the amount of data which needs to be stored in healthcare growing exponentially, but the time periods over which the data must remain available are also increasing. At the same time, healthcare organizations must adhere to strict requirements and legal guidelines. Various laws require hospitals and clinics to retain data for decades.

Because retention periods of up to 30 years are possible (e.g., in radiation treatment and X-ray therapy), the entire data storage must also be replaced several times, because the systems used for storage today will no longer be state of the art in 30 years. In practice, systems are often changed much earlier because the solutions often do not meet actual needs, have lost efficiency, or were designed under-/over-sized. This leaves IT managers in hospitals struggling with uncertainties about which technologies and data volumes to expect in the future.

The result is expensive and time-consuming new acquisitions as well as complex migration processes which hinder everyday running of the hospital. The storage and archiving of PACS data as well as other medical data is therefore facing a paradigm shift towards more future-proofing and flexibility.