Going Mobile…

Selecting a Mobile Medical Image Viewing System to Meet Your Needs

By Christie Henschl, staff writer

With ever-evolving legislation, business models and treatment guidelines, today healthcare is rapidly on the move. And happily, today’s mobile imaging applications will help radiologists—and any physician concerned with image viewing—keep pace. Today, mobile systems for viewing and even interpreting diagnostic images run on almost any device across all platforms.
While there are a wide variety of mobile technologies to choose from, not all are created equal. How carefully you should examine the marketplace and what you need to seek out when deciding on a purchase depends to a large extent on your intended use, on the number of physicians it will be supporting—and supporting simultaneously – how much in-house IT expertise you wish to contribute to the project and the types of advanced features doctors demand.

Today, you can easily find a high quality mobile image viewing system that is feature-rich, easy to use, secure, and affordable to provide high quality images on a mobile device while you are running around your hospital or are on call. On some systems, you can actually experience performance similar to a standard PACS viewer—with all the bells and whistles—but finding the right one isn’t always a carefree walk in the park.

Technology Overview

First, just how does a mobile viewing system work? It depends on who you ask. Web-based viewers may use a browser for image display, but can still employ proprietary technology, limiting the usefulness of the images. At times, vendors are less than literal with their descriptions—so buyer beware. Many vendors use the terms cloud-based, thin-client and zero-footprint rather loosely. However, today most viewers rely on cloud technology or—or proprietary cloud–to some degree. This means that most or all of the application itself, the data being viewed and the computing power behind the system reside on a special offsite server dedicated to mobile viewing.
Typically images to be accessed on a mobile device are sent to this -offsite server from a PACS or other image archive. Users access the server through a web browser and interact with the application and imaging data remotely. The image usually does not download to your device and any manipulations you perform utilize the computing power of the server itself. When viewing an image, an authorized user will log into the application with secure authentication protocols, find the desired image and continue from there. The device’s mobile connection also is an important ingredient in the mix. Secure and fast mobile networks are a must for high performance.

Mobile Viewing Use Cases

Mobile viewing, of course is a convenience for radiologists, allowing them to work in the location of their choice. It also enables them to view and interpret images when needed, even if they are not working a shift, realizing faster diagnosis and enhancing patient care. However, the technology supports a variety of other important use cases.
These include:
• Cross-enterprise image sharing for collaboration and second opinions.
• Cross-enterprise image sharing for trauma transfers and other emergency cases, enabling decision-making on a case before the patient is transferred.
• Image viewing across the enterprise outside of a PACS solution through a VNA or other enterprise-class archive.
• Referring physician images access, typically through a physician web portal.
• Image viewing across a health information exchange (HIE).
Not every viewer is a good selection for every one of these use cases, and technology choices must be predicated on every site’s needs.

The Format

The early wave of mobile viewers was based on thin-client technology, with most of the viewing application running from a server. However, a plug-in or download of various sizes on the mobile hardware was required. Today, many mobile applications continue as thin client applications. During the past few years, some vendors have progressed to a flavor of “zero-footprint” technology that still requires installing FLASH software on the device. However few are providing a viewer which requires absolutely no software residing on the viewing device.
From an IT perspective thin client technology can create a complex and difficult to maintain IT environment. Radiology and hospital administrators need to support the portions of the viewing solution running on remote devices in an uncontrolled operating environment—your iPhone or tablet, which may be used very casually compared to an in-house viewing system. Also, upgrading and maintaining the resident portion of the viewing software across multiple devices under an individual user’s control may become a difficult and frustrating for IT staff.
Therefore, a zero-footprint solution offers numerous advantages over thin client technology. But on the down side, it can demand a compromise on advanced features. The issue, in part, is the ability of the user interface on a local device to control an application running on a remote server quickly and efficiently in order to manipulate images as desired. Some vendors have invested significant efforts in making the most of wireless bandwidth to enhance performance and to integrate the most sophisticated viewing functionalities into their systems. Therefore the viewers deliver the best of both worlds.

Features and Functionalities

Whether to deploy a thin-client or true zero-footprint viewer is just one decision. Next, technology purchasers must look closely at a viewer’s features and functionalities and consider the following:

• Viewing and Image Manipulation
Think big, and think ahead. Most mobile device viewing systems support a full spectrum of modalities. Many also offer a range of tools such as pan, level and zoom as well. The field gets smaller for such advanced features as MIP and volume rendering as well as for advanced measurement tools such as ellipse, contour, ROI, Cobb angle. A few viewers will also support full dynamic cardiology exams with multiple synchronized cine loop and multimodality oncology fusion. If users expect PACS workstation quality performance, be aware that it does exist. So make sure you select the appropriate solution.

• Security and Authentication
The use of server-side rendering technology itself provides a large measure of security because images are not downloaded to individual devices that can be lost, stolen or used casually. However, in an uncontrolled environment, security and authentication requirements are far greater than in a hospital environment. A system leveraging industry standard web protocols like secure HTTPS enhances security while greatly reducing the user’s security management costs.

Support for single sign-on on in your specific security environment is important. Many institutions will find Windows integrated authentication suitable, but those using other authentication methods should look for a mobile solution that can delegate authentication to support existing methods. Typically this is supported through an open API to external system. Also important is the system’s ability to grant secure temporary access to users without requiring a permanent account to facilitate collaboration with external partners.
Lastly mobile solutions must log into an audit trail for all access and significant operations.

• Maximizing Available Bandwidth
Viewing large medical images from different modalities in various formats in a pure zero-footprint viewer is a difficult technological challenge, particularly over a wireless network. The solution’s adaptability to different bandwidth is a must. Also important is the ability to work smoothly across a number of different latencies—simply put, the time it takes for communication between the mobile device and the server. Latency increases with the physical distance between the client and server, and can also be very variable with wireless connectivity. Look for experienced companies with smart- streaming technologies. Also pay attention to the features supported and speed and smoothness of the viewing experience. Ideally these should be similar to a desktop system.

• Ease-of-Use
It goes without saying that an easy-to-use system is desirable. But from an occasional user’s perspective, a system may be user-friendly, while from a radiologist’s standpoint it may be limiting. Also look for a consistent workflow across different device. The best solutions out there, will not force you to learn different way of working on different devices, but will take full advantage of the natural platform interaction, like gestures on smartphones and tablets.

• Privileges, Roles and Groups
Some viewers allow users to be categorized and granted viewing rights based on group assignment. This streamlines security measures and upholds HIPAA regulations. If you intend to use the system for referring physician communication, trauma transfers, and any sort of collaboration, these considerations will be extremely important. For example, some viewers provide maximum flexibility and rules-based definition of privileges. Administrators will have a full set of user privileges including managing the user group function itself. The ability to customize privileges for roles and user groups and to easily assign them can be crucial.

• Image Pre-Fetching and Streaming
A pre-fetch service can retrieve archived images from external sources based on an anticipated need and save them to the cloud server. Some systems support sophisticated user-determined pre-fetch rules that automatically access required images for mobile viewing. This particularly benefits physicians who need to review prior exams along with current patient studies. Some systems can be configured to perform pre-fetching during evenings or off hours to minimize network traffic. For situations where anticipating the need for images in advance is not possible, look for solution that can stream images directly to remote archives. The best solution will support this with no impact on workflow.

• Remote Image Sharing
Typically most images viewed already reside on a PACS and are available to the viewer’s server. However certain clinical situations call for actual data exchange between facilities, for example, for a transfer patient with existing images that need to be added to the patient record, or for assessing the need to transfer a trauma patient from an outside facility. Some sophisticated systems support actual file transfer, with a high level of security – without r a VPN. If your mobile image viewing application needs to view images in the scenarios above, look closely at the features each vendor offers.

• Scalability
Selecting a system that can support the number of anticipated users and volume of images to be shared is a major consideration. Server configuration plays a key role in this. Servers may be hardware-based or virtual, and high-volume facilities may require several. If this is the case, load-balancing technology will help assure images are available to all users when needed.

In addition, servers are required to interface with the image archives storing the remote viewing data—whether simply a PACS or possibly an enterprise VNA or XDS data source. Some viewers enable data from all these sources can be federated and streamed in real time or pre-fetched as needed. In these cases, patient consolidation is important, and sites using an eMPI (Electronic Master Patient Index) to reconcile patient identifiers must make sure their mobile solution supports this. If you are planning an ambitious installation or one that will grow in the future, make sure your remote access vendor offers a robust server set up that will meet your needs.

• Image Viewing Beyond Radiology
Will physicians other than radiologists be viewing images remotely—for example cardiologists, pathologists or ophthalmologists? If so, you will need to make sure that the device viewer supports both DICOM as well as non- DICOM image formats. Make sure the system has a way to push images to the server from sources other than a DICOM source. Alternately, some systems have features that will automatically translate other imaging data to DICOM.

• Set-Up and Maintenance
Factors that impact set-up and operational costs include whether the system utilizes industry standard web protocols (secure HTTPS), require software on the client devices such as Flash, or a VPN. Extremely important is the ability to run in a virtualized environment without any special GPU acceleration. This will allow sites to host your mobile solution in their data center or with a cloud provider in an affordable and scalable way.

The Selection Process

The bottom line is that a mobile image viewing application should meet your full range of needs and be simple to use—but finding the right system is not quite so simple. Other than the very apparent image quality, the flexibility and power of the backend will have a substantial impact on a successful implementation. Start by surveying all your users and make a check list of expectations. Survey multiple vendors, ask for references and do your homework. Remember, in the mobile world, site visits are as simple as looking at images on a user’s mobile device.