Thin-client computing bringsworkstation apps to desktop

Diagnostic ImagingDiagnostic Imaging Vol 31 No 4
Volume 31
Issue 4

Like devout joggers, thin-client technology keeps getting thinner and thinner. Some clients are now so thin they are virtually transparent.

Like devout joggers, thin-client technology keeps getting thinner and thinner. Some clients are now so thin they are virtually transparent.

First came thin clients, in which the bulk of data processing is removed from client workstations and placed on central servers, leaving just the operating system and communication routines on the client.

Ultrathin clients evolved next. These take thin-client computing a step further by moving the operating system and other software to the server side without imposing any software requirements on the client.

The latest iteration of thin-client architecture is called a zero-client, or zero-download. Zero-clients are not much more than dumb monitors. By definition, they have no operating system, no drivers, no memory, and no central processing unit. In August 2007, Pano Logic unveiled a zero-client half the size of a Rubik's Cube: a box less than 3.5 inches square that connects keyboard, mouse, monitor, audio, and universal serial bus peripherals over an existing 100- Mb/sec local area network to a copy of Windows running elsewhere on a virtualized server. (Virtualization is a method of running multiple independent virtual operating systems on a single server.)

The appeal of all thin-client technologies to radiology is that they exploit server processing power while minimizing processing requirements on client workstations. Data-intensive applications are then run on the server rather than on the client. A true thin client means neither the vendor nor the customer needs to install any software on client devices; data are dynamically downloaded as needed.

With servers using multicore processors and blade technology providing all the horsepower, workstations can now be standard desktop PCs-or even PDAs, BlackBerrys, or Smartphones-rather than dedicated high-end monitors.

Thin-client technologies are key to providing instant access to PACS images and reports to a broad range of clinical users without worrying about physician location or incongruous hardware or software.

“Users can access diagnostic images and perform image processing, such as windowing and 3D, from any location where fast Internet connectivity is present, from any department in the hospital, or from any offsite practice office,” said Henri “Rik” Primo, director of marketing and strategic relationships for Siemens Medical Solutions.

Contemporary radiology applications challenge IT networks with massive file transfer demands. Thin-client technologies handle this traffic better than conventional PCs because thin clients are not moving the actual files; only the pixels required to paint the monitor are being transmitted.

Vendors in the advanced visualization market are beginning to leverage technologies such as XML messaging, user interfaces based on Adobe Flash, and Microsoft's .NET and Silverlight frameworks to provide ultrathin and zero-download software applications to the clinical end-user. For complex 3D processing, for example, software packages are pushed from server to client PC. No local install of software by field engineers is needed.

“It's the best of both worlds: rich-client performance and thin-client convenience,” Primo said.

Siemens already uses thin and richthin technology in solutions for remote image processing applications. Its syngo WebSpace offers 3D and 4D tools in the syngo InSpace4D user interface, which is available to any syngo WebSpace client.


Thin and ultrathin client technologies are not exactly new. They have been emerging for several years. The lower cost of ownership, simplified setup, enhanced customer support, and ease of overall system management from the facility level hold appeal for healthcare and radiology.

“Thin-client computing makes for more flexibility and independence in the choice of client workstations and allows the system to be managed from the server end in the IT department,” said Nadim Daher, a senior healthcare industry analyst at market research firm Frost & Sullivan.

The principal advantage of ultrathin clients is that the extremely low processing power needs on the client side allow mobile and embedded devices of any kind access to advanced applications.

“Referring physicians can be provided access to clinical images and information without any cumbersome downloads or supporting software,” said Kang Wang, Ph.D., senior vice president of research and development and chief technology officer at Amicas.

Amicas embraced thin-client architecture with its PACS some time ago. Its newer ultrathin Amicas Reach solution provides a zero-installation platform for clinicians.

Ultrathin-client computing provides key advantages to both radiologists and referring physicians.

Clinicians can now get radiology results in the office, at home, on the road, or in their pocket. GE Healthcare, for one, is actively developing a number of initiatives in this space and has several products that may run in very thin client environments. One solution sends images from GE's Centricity PACS to an iPhone for remote consultation.

Ultrathin technologies also allow radiologists to more fully utilize reading resources. Exam reading can be performed by radiologists and specialists at any location with most of the same toolsets and functionality they have in the office reading room.

Patients also benefit. Ultrathin computing helps reduce the need for radiologists to travel, greatly accelerating report turnaround. It can take days for patients to receive a final diagnosis from an exam performed at a small rural clinic where radiologists are onsite only two days a week.

“With the scarcity of radiologists worldwide, thin-client technologies enable rapid, universal access to radiologists and specialists for patients at all healthcare facilities, regardless of location or availability of onsite resources,” said Hadas Padan, director of healthcare information solutions at Carestream Health.

Padan said Carestream's PACS and SuperPACS architecture expedites radiology workflows by delivering an identical user interface and toolset for radiologists and remote clinicians.

“This architecture was designed to work synergistically with webenabled technology to deliver the speed and functionality of a diagnostic workstation from any remote PC,” Padan said. Thin-client computing also offers productivity opportunities for radiologists staffing remote clinics. When the workload from local cases is light, they can contribute to the home practice's overall workflow by accessing cases remotely over thinclient networks.

“Workload balancing such as this can create a premium virtual radiologist network,” Wang said.

Claes Lundström, Sectra's director of upstream marketing and research, believes ultrathin clients are most useful when you have a large distributed user group and the only part of the IT environment that can be counted on is the web browser.

“Groups that need ultrathin applications are specialists with unusually poor IT environments or referring physicians with unusually high image review demands,” Lundström said. Sectra has ultrathin solutions for result distribution, including basic image display, Lundström said. Sectra is looking closely into ultrathin architectures within image review and advanced visualization for the future.

“We're also making sure that our efforts are driven by customer value and not technology hype,” he said.


Hyperbole surrounding ultrathin client computing for radiology tends sometimes to distort realities. The technology has its limits.

Advanced ultrathin-client applications are confined in their presentation capabilities by bandwidth and client memory capacity. The price of flexibility gained by thinclient technology is that applications must run in a highly constrained, secure box with limited resources.

“You can't write to disk or access system resources like CD burners or microphones, so the question becomes whether useful applications can be defined so they can run in the box,” said Stuart Long, senior director of Philips Healthcare's global product management and marketing.

In radiology, the best candidates for ultrathin-client applications are the ones with lower data transfer requirements.

“Applications that access electronic medical records and 3D reconstruction applications that stream results as movies would be good candidates for ultrathin models,” said Khal Rai, general manager of GE Healthcare IT.

Conversely, applications that require a high degree of user interactivity or higher storage demands for keeping large imaging studies on the client are less suitable for ultrathin- client computing, since interactive postprocessing and random access navigation of large studies are difficult to achieve under this model. With ultrathin models, lower client hardware requirements and increased client mobility are swapped for limitations in interactivity and the amount of data that can be accessed immediately.

“Ultrathin technology is more movie-watching, with an occasional flashback to a particular scene, than movie-making,” Rai said.

The best approach may be to provide ultrathin-client access where appropriate and the higher performance and functionality of thicker clients when needed and appropriate.

The notion of having a thin application is great, but there is often the need to deploy, manage, and support a relatively thick infrastructure to enable the thin application.


The impact of ultrathin architecture on radiologist efficiency, image analysis capability, and image quality is another concern with thin-client computing.

Clinical multimedia such as 3D ultrasound and diagnostic images need to be accessed, managed, manipulated, stored, and distributed to specialists and clinicians across the enterprise and beyond with speed and efficiency.

Whether ultrathin architectures are up to these demands is not yet known. Although ultrathin-client applications significantly ease concerns about the hardware component of advanced visualization solutions, these implementations place increased importance on enterprise network performance, as well as networks that access the solution remotely. “Initial ultrathin applications may not be able to accomplish these goals,” said Fujifilm Medical System's Jim Morgan, director of marketing for network systems.

While a connection speed of 2 Mb/sec may provide acceptable speed and display performance for static 2D images, dynamic real-time display performance of cine clips such as angiography exams and Doppler ultrasound may suffer from less than optimal bandwidth, resulting in a less than smooth display experience.

“In these cases, a rich-thin client instead of a thin client may provide better performance by shifting some processing functions back to the client workstation or PC,” Primo said.

Latency is another consideration in an ultrathin-client environment. If bandwidth is the road's speed limit, latency is how often you are stopped at a traffic signal trying to get from point A to point B.

“With ultrathin clients, every interaction has to be processed by the server, so even the smallest operation may be subject to delays due to latency,” Lundström said.

Technologies are making it ever easier for clinicians to work remotely. But their needs will challenge vendors.

“As access extends outside the hospital network, software developers must ensure their applications perform well on low-bandwidth networks, often with poor latency,” said Don Dennison, director of eHealth and regional health business for Agfa Healthcare.

Agfa is one of the major players moving toward ultrathin- and zeroclient applications. At the 2008 RSNA meeting, Agfa unveiled a work-inprogress zero-client solution that allows viewing of medical images, reports, and other multimedia content without any software download to the client.

The good news is that ultrathinclient technology is improving steadily, and trade-off gaps are beginning to shrink. Wang acknowledged there may be a few features and functions that are inaccessible with ultrathin applications simply because they require so many resources in terms of RAM and CPU power. But ultrathin applications are designed to satisfy the needs of the majority of customers, he said.

“It's been proven that thin clients can deliver the same or better functionality than fat clients, with more flexibility and much less IT overhead,” Wang said.


Adoption by mainstream radiology until now has been cautious.

“Thin-client technology is still in its infancy in terms of market adoption in radiology,” Daher said.

Adoption of thin-client architectures may be the rare case in which radiology lags behind healthcare IT in general, he said.

“Lightweight information-based systems are easier to deploy over thin clients than data-intensive imagebased radiology applications,” he said.

While thin- and ultrathin-client technologies may not be the perfect mate for radiology in all cases, the industry is beginning to see image viewers and other rich applications using thin-client and ultrathin-client architectures. It is just within the last few months that all hardware and software pieces have come together to make a strong, robust solution that

IT departments could implement. Changes in software licensing models and decreases in hardware costs now make it a compelling strategy.

Thin-client architectures until recently have been marketed mainly by niche players, but several major radiology vendors are now maneuvering in the direction of thinner and thinner client solutions.

Some firms, like Fujifilm, have predicated their technological future on the Internet as the conduit for all clinical data.

“This is not just because of the success of cloud computing models, but because some of the most innovative concepts in computing and communication technology have come from web solutions,” Morgan said.

Philips sees the need for what were once considered specialty applications, such as 3D and dynamic volume data sets.

“These are now considered mandatory for nearly all users of electronic medical records,” Long said.

Philips intends to replace its existing thin-client iSite Enterprise application with a true ultrathin solution, he said. “Ideally, no install will be required,” he said.

One of the drivers behind radiology's interest in ultrathin-client solutions is the technology's positive impact on business. As radiology practices grow their business, they need to leverage their radiologists while attracting and maintaining a referring physician base.

“Simple thin and ultrathin clients help radiology practices achieve both objectives,” Wang said.

Related Videos
Practical Insights on CT and MRI Neuroimaging and Reporting for Stroke Patients
Emerging Innovations in Molecular Imaging
Related Content
© 2023 MJH Life Sciences

All rights reserved.