PACS: What It Is, How It Works, and How Medical Imaging Practices Manage Images
Updated: Aug 24
PACS stands for Picture Archiving and Communication System. It is a medical imaging technology used to store, manage, retrieve, view, and communicate digital medical images.
PACS is commonly used with imaging modalities such as:
Digital X-ray
CT
MRI
Ultrasound
Mammography
Fluoroscopy
Other DICOM-compatible imaging systems
Instead of relying on physical film or manually transferring images between departments, a PACS system allows digital images to be stored and accessed through a connected imaging network.
For healthcare organizations managing a growing volume of digital images, PACS can become an important part of the imaging workflow.
How Does a PACS System Work?
A PACS system connects medical imaging equipment with image storage, viewing, and communication tools.
A typical workflow looks like this:
Imaging Modality → DICOM → PACS → Image Storage → Workstation / Viewer
For example, a patient may have an X-ray examination.
The imaging system generates a digital image and sends it using the DICOM standard.
The PACS receives the study and stores the associated imaging information.
An authorized healthcare professional can then access the images from a connected workstation or compatible viewer.
This workflow helps reduce manual image transfers and makes digital imaging studies easier to organize and retrieve.
What Does PACS Stand For?
PACS stands for:
Picture Archiving and Communication System
Each part describes an important function:
Picture — Medical images such as X-rays, CT scans, and ultrasound studies
Archiving — Storing imaging studies for later access
Communication — Sending and sharing images across connected systems
System — The combination of software, storage, networking, and viewing components
PACS is therefore more than an image viewer. It is an imaging-management system designed to support the movement and storage of medical images.
What Is DICOM?
DICOM stands for Digital Imaging and Communications in Medicine.
DICOM is a widely used standard for storing, transmitting, and communicating medical imaging information.
DICOM allows compatible imaging equipment and software from different manufacturers to communicate using standardized information.
For example, a digital X-ray system can send a DICOM study to a PACS system.
The study can contain both the image and associated information needed to identify and manage the examination.
PACS vs. DICOM: What Is the Difference?
PACS and DICOM are related, but they are not the same thing.
PACS | DICOM |
Imaging management system | Imaging communication standard |
Stores and manages images | Defines how imaging information is formatted and communicated |
Provides access to studies | Allows compatible systems to exchange imaging data |
Includes software and infrastructure | Used by imaging devices and software |
Supports imaging workflow | Supports interoperability |
A simple way to understand the difference is:
DICOM is a standard, while PACS is a system that uses standards such as DICOM to manage medical imaging.
What Is a DICOM Viewer?
A DICOM viewer is software that allows healthcare professionals to open and review medical images stored in DICOM format.
Depending on the software, a DICOM viewer may provide tools such as:
Zoom
Pan
Measurements
Window and level adjustment
Image comparison
Multi-planar viewing
Image annotations
Study navigation
3D visualization
A DICOM viewer can be a component of a PACS environment, but not every DICOM viewer is a complete PACS.
A basic viewer may simply open and display images, while a PACS can provide broader functions for image storage, organization, communication, and workflow management.
What Types of Medical Images Can PACS Manage?
PACS can be used with many types of digital imaging studies.
Digital X-Ray
Digital radiography systems can send X-ray studies to PACS for storage and viewing.
CT
CT scanners can generate large numbers of images per examination, making organized image management particularly important.
MRI
MRI studies can contain multiple sequences and large volumes of image data.
Ultrasound
Ultrasound systems can generate both still images and other types of digital imaging information, depending on the system.
Mammography
Digital mammography systems can generate high-resolution studies that require appropriate storage and viewing capabilities.
Fluoroscopy
Fluoroscopy systems can produce imaging data that may be integrated into a broader imaging workflow.
The exact modalities supported depend on the PACS configuration and compatibility of the connected systems.
Why Do Healthcare Facilities Use PACS?
As medical imaging becomes increasingly digital, healthcare organizations need reliable ways to manage imaging data.
A PACS can help organizations:
Centralize image storage
Access studies digitally
Organize imaging examinations
Reduce reliance on physical media
Share images across connected locations
Support diagnostic workflows
Retrieve previous examinations
Connect multiple imaging modalities
The specific benefits depend on the PACS architecture and how it is integrated into the facility's workflow.
PACS in a Medical Imaging Workflow
A typical medical imaging workflow may include several stages.
1. Patient Registration
The patient is registered in the healthcare information system.
2. Imaging Examination
The patient undergoes an X-ray, CT, MRI, ultrasound, or another imaging examination.
3. Image Creation
The imaging modality creates digital images.
4. DICOM Transmission
The imaging system sends the study using DICOM communication.
5. PACS Storage
The PACS receives and stores the study.
6. Image Review
An authorized user opens the examination using a workstation or DICOM viewer.
7. Diagnosis and Reporting
The healthcare professional reviews the images and completes the appropriate clinical documentation.
8. Long-Term Access
The study can remain available according to the facility's storage and retention policies.
PACS and Digital X-Ray
Digital X-ray systems are commonly integrated with PACS.
A typical workflow is:
X-Ray System → DICOM → PACS → DICOM Viewer
This allows digital radiographs to be sent directly from the imaging system into an image-management environment.
For facilities using multiple X-ray systems, PACS can help centralize access to studies rather than requiring staff to manage images separately on individual imaging workstations.
PACS and CT Imaging
CT examinations can produce hundreds or even thousands of individual images depending on the scanner, protocol, and reconstruction settings.
Managing this volume of imaging information can be difficult without an organized system.
A PACS can provide a centralized location for CT studies and allow authorized users to retrieve and review examinations.
For facilities with multiple imaging modalities, integrating CT with PACS can also help create a more unified imaging workflow.
PACS and Ultrasound
Ultrasound systems can also be connected to PACS when appropriate DICOM functionality is available.
Depending on the system, ultrasound examinations may include:
Still images
Measurements
Study information
Other supported imaging data
Connecting ultrasound to PACS can help keep imaging studies organized alongside examinations from other modalities.
Benefits of a PACS System
Centralized Image Access
A PACS can provide a centralized location for imaging studies.
Faster Image Retrieval
Users can search for and retrieve previous examinations without manually locating physical film or discs.
Digital Image Sharing
Images can be shared across authorized systems and locations when the PACS environment is appropriately configured.
Reduced Physical Storage
Digital imaging reduces the need for physical film storage.
Better Access to Previous Studies
Previous examinations can be available for comparison when properly stored and retained.
Support for Multiple Modalities
A PACS can potentially connect multiple types of imaging equipment within one imaging environment.
PACS and Remote Image Access
Some PACS environments support remote image access.
This can allow authorized users to review imaging studies from locations outside the imaging department, depending on the system architecture and security controls.
Remote access can be useful for:
Multi-location healthcare organizations
On-call radiologists
Remote consultation
Specialist review
Distributed imaging departments
Remote access should always be configured with appropriate security, authentication, and privacy protections.
PACS for Multi-Location Healthcare Facilities
Healthcare organizations operating multiple locations may have imaging systems distributed across different facilities.
A properly designed PACS environment can help connect these imaging systems.
For example:
Location A → PACS
Location B → PACS
Location C → PACS
Authorized users can potentially access studies from a centralized environment depending on the network and PACS configuration.
This can help organizations create a more consistent imaging workflow across locations.
Cloud PACS vs. Local PACS
PACS can be deployed using different architectures.
Local PACS
A local PACS stores imaging data on infrastructure managed within the healthcare facility or organization.
Potential advantages include:
Local control
Internal network access
Direct management of infrastructure
However, the facility may be responsible for hardware, storage, backups, maintenance, and other infrastructure requirements.
Cloud-Based PACS
A cloud-based approach stores some or all imaging data using cloud infrastructure.
Potential advantages can include:
Remote accessibility
Scalable storage
Reduced on-site hardware requirements
Easier access across locations
However, organizations must carefully evaluate connectivity, security, privacy, service availability, and ongoing costs.
The right architecture depends on the organization's requirements.
PACS Storage and Data Management
Medical imaging can generate a large amount of data.
Storage requirements depend on:
Number of examinations
Imaging modalities
Image resolution
CT slice count
MRI sequences
Retention requirements
Number of facilities
Expected growth
A PACS implementation should therefore include a storage strategy.
Healthcare organizations should consider:
Primary storage
Backup storage
Disaster recovery
Data retention
Storage expansion
Network capacity
PACS Backup and Disaster Recovery
Medical imaging data can be extremely important to patient care.
A PACS strategy should therefore include appropriate backup and disaster-recovery planning.
Consider:
Automated backups
Redundant storage
Off-site backup
Disaster recovery procedures
Recovery testing
System redundancy
A backup should not simply exist—it should also be tested to make sure data can actually be restored when required.
PACS Security
Medical images contain sensitive patient information.
A PACS environment should therefore include appropriate security measures.
Depending on the system, security considerations can include:
User authentication
Access controls
Encryption
Audit logs
Network security
Backup security
Role-based permissions
Secure remote access
Healthcare organizations should configure their PACS environment according to applicable privacy, security, and regulatory requirements.
PACS Integration With Other Healthcare Systems
PACS doesn't necessarily operate independently.
It may need to communicate with other healthcare information systems.
Depending on the facility, PACS may interact with:
Electronic medical records
Radiology information systems
Hospital information systems
Modality worklists
Reporting systems
DICOM devices
Proper integration can reduce manual data entry and help improve imaging workflow.
What Is a Modality Worklist?
A modality worklist can help imaging equipment receive scheduled patient and examination information electronically.
Instead of manually entering patient information at the imaging console, compatible systems can retrieve information from a worklist.
A typical workflow may look like:
Scheduling System → Worklist → Imaging Modality → DICOM → PACS
This can help reduce manual entry and potentially reduce errors associated with retyping patient information.
PACS vs. Image Storage
A simple file-storage system and a PACS are not necessarily the same.
A general storage system may store files, but PACS is designed specifically around medical imaging workflows.
PACS can provide functions such as:
DICOM communication
Study organization
Patient-based image retrieval
Imaging viewers
Modality integration
User management
Imaging workflow support
The appropriate solution depends on the imaging environment and the organization's requirements.
How to Choose a PACS System
Choosing a PACS system should begin with understanding your current imaging workflow.
1. Identify Your Imaging Modalities
Determine which systems need to connect to the PACS.
2. Determine Your Imaging Volume
Estimate current and future study volumes.
3. Check DICOM Compatibility
Confirm that your imaging equipment and PACS can communicate correctly.
4. Evaluate Storage Requirements
Consider current storage requirements and future growth.
5. Review the DICOM Viewer
Evaluate the image-viewing tools and workflow.
6. Consider User Access
Determine which users and departments need access.
7. Evaluate Remote Access
If remote viewing is required, review the available architecture and security controls.
8. Review Backup Options
Understand how imaging data is backed up and recovered.
9. Evaluate Integration
Determine whether the PACS can integrate with other systems used by the facility.
10. Consider Support
Technical support is important when PACS becomes a central component of an imaging workflow.
PACS Buying Checklist
Before selecting a PACS system, ask:
What imaging modalities need to connect?
Is the equipment DICOM compatible?
How much imaging data is generated each month?
How much storage is needed?
How quickly can images be retrieved?
What DICOM viewer is included?
Can multiple users access the system?
Is remote access supported?
How are user permissions managed?
What backup options are available?
What disaster-recovery options are available?
Can the PACS integrate with existing healthcare systems?
Is modality worklist supported?
What security features are available?
What technical support is provided?
What are the ongoing costs?
Common PACS Problems
PACS systems can experience technical problems for many reasons.
Common issues can include:
DICOM Communication Errors
An imaging modality may fail to communicate correctly with the PACS because of configuration problems.
Incorrect AE Titles
DICOM devices commonly use Application Entity Titles to identify communication endpoints. Incorrect configuration can prevent communication.
Incorrect IP Address or Port
Network configuration problems can prevent an imaging system from connecting to the PACS.
Storage Problems
Insufficient storage or storage failures can affect image availability.
Network Problems
Slow or unstable network connections can affect image transfer and remote viewing.
Worklist Problems
Incorrect configuration between the modality and worklist server can prevent scheduled patient information from appearing at the imaging console.
Viewer Compatibility
Different systems may support different features, so compatibility should be evaluated before implementation.
PACS and DICOM Configuration
When connecting an imaging modality to a PACS, several DICOM parameters may need to be configured.
Common settings can include:
AE Title
IP address
Port
DICOM destination
Storage settings
Verification settings
Worklist settings
The exact configuration depends on the imaging equipment and PACS software.
Proper configuration is essential for reliable image transfer.
Why DICOM Compatibility Matters
If an imaging device and PACS cannot communicate correctly, images may not transfer as expected.
Before purchasing or integrating equipment, verify:
DICOM support
Supported DICOM services
Storage compatibility
Modality worklist support
Query/retrieve capabilities
Network requirements
A PACS supplier or imaging-equipment provider should be able to help determine the appropriate configuration.
Introducing CVPACS
For healthcare organizations looking for a PACS solution, CVPACS is designed to support the management of digital medical imaging.
CVPACS can be positioned as part of an imaging workflow that connects compatible imaging equipment with image storage and viewing.
Depending on the configuration, a PACS environment can help healthcare facilities organize imaging studies and provide authorized users with access to digital images.
For facilities evaluating PACS, the most important consideration is how the system fits into the organization's existing imaging workflow.
Who Can Benefit From PACS?
PACS can be useful for many healthcare environments that generate and manage digital medical images.
Examples include:
Hospitals
Diagnostic imaging centers
Radiology departments
Medical clinics
Specialty practices
Multi-location healthcare organizations
Imaging facilities
The appropriate PACS configuration depends on the facility's imaging volume, modalities, workflow, and technical requirements.
Frequently Asked Questions About PACS
What does PACS stand for?
PACS stands for Picture Archiving and Communication System.
What is PACS used for?
PACS is used to store, manage, retrieve, view, and communicate digital medical images.
What is a PACS system?
A PACS system is a combination of software, storage, networking, and image-viewing tools designed to manage digital medical imaging.
Is PACS the same as DICOM?
No. DICOM is a standard for communicating and managing medical imaging information, while PACS is an imaging-management system that commonly uses DICOM.
What is a DICOM viewer?
A DICOM viewer is software used to open and view medical images stored in DICOM format.
Can PACS store X-ray images?
Yes. PACS can store digital X-ray studies when the imaging system and PACS are appropriately configured.
Can PACS work with CT?
Yes. CT systems can send DICOM imaging studies to PACS for storage and viewing.
Can PACS work with ultrasound?
Yes, when the ultrasound system supports compatible DICOM functionality.
Does PACS replace DICOM?
No. PACS and DICOM serve different purposes. PACS manages imaging, while DICOM provides standardized communication and formatting.
Can PACS be accessed remotely?
Some PACS systems support secure remote access. The specific capabilities depend on the system configuration and security architecture.
How much does PACS cost?
PACS costs vary depending on the number of users, imaging volume, storage requirements, software features, integrations, deployment model, service, and other factors.
What should I consider when choosing PACS?
Consider DICOM compatibility, imaging modalities, storage, image viewing, user access, security, backups, integration, remote access, scalability, and technical support.
Final Thoughts
PACS has become an important part of digital medical imaging because it provides a structured way to store, manage, retrieve, and view imaging studies.
A well-designed PACS system can connect imaging modalities such as X-ray, CT, MRI, and ultrasound while helping healthcare organizations manage growing volumes of digital images.
DICOM plays an important role in this environment by providing standardized methods for imaging systems and software to communicate.
When selecting PACS, healthcare organizations should look beyond the image viewer and consider the entire imaging workflow, including storage, communication, security, backups, integration, scalability, and technical support.
For facilities evaluating PACS solutions, understanding these components can make it easier to compare systems and choose an imaging-management solution that fits their current and future requirements.
Need Help Choosing a PACS Solution?
Choosing the right PACS system depends on your imaging equipment, workflow, storage requirements, and future needs. If you're evaluating PACS, DICOM connectivity, or medical imaging solutions, Medna Medical Equipment can help you explore the options available for your facility.
Contact Medna Medical Equipment to discuss your imaging requirements and learn more about CVPACS and other medical imaging solutions.
Looking for a PACS solution for your practice? Contact Medna Medical Equipment today to learn more.
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