By: Wouter Stomp, MD
As we recently reported, Carestream has received FDA clearance for its Vue Motion HTML5 based medical image viewer. This is a major step forward in ensuring cross-platform availability, theoretically making it accessible from any device that has a web browser.
Although other vendors have released apps for the iPad and other tablets to access their PACS systems, Vue Motion is the first web-based viewer that we know of that can be accessed from tablets without installing additional software.
We took the viewer for a spin, testing it on a variety of devices. We received access to a demo server from Carestream which had several example patients with modalities including x-ray, ultrasound, CT and MRI.
iPad
First up, of course, was the iPad. Our tests were performed on an iPad 2 as recommended by Carestream.
They recommend turning the brightness all the way up and provide a link to some calibration images from the login screen (although other than brightness there is not much that you can change on an iPad).
After browsing to the server address and entering our credentials, we were presented with a search box to look up patient studies.
Looking up patients and opening studies was fast enough. Individual studies open in a tab-based interface, which is clean and simple, devoid of any unnecessary clutter.
On the left and right are drawers with the patient history (previous studies) and study reports and notes respectively. At the bottom there are buttons for moving through the image stack, zoom, moving the image, window/level, measurements, rotating the image and reloading it. In addition there are controls for selecting the image series and a play button for moving images.
The selected action is assigned to one-finger gestures, however you can also use two fingers to pinch and zoom and move the image around.
Performance
Our tests were a bit of a stress-test, accessing the servers from the Netherlands across the translatlantic internet cables, with a high-speed internet connection (20Mb/s DSL). Images showed up almost instantly, only rarely showing a loading screen in between. Images can also be played in a movie mode which also displayed smoothly in most cases. What can be a small annoyance is that images are first loaded in low-resolution, introducing a short flicker a fraction of a second after you scroll to a different image.
The images are rendered on the server and sent to the viewer in a loss-less format with compression varying with image detail and zoom level. Typical compression was between 1:10 and 1:50. There is a button that will load the current image loss-lessly for optimal image quality, however the difference is usually imperceptible, so we would recommend just staying with the default images. Data usage may be an issue if you plan to use the viewer over 3G, however we were not able to test this as the test iPad was wifi-only.
Desktop
On the PC you are presented with exactly the same interface as on the iPad. Although it is great to have a consistent interface across all platforms, it does feel a bit clunky with its large touch-screen optimized UI elements. Other than that, it works equally as well as it does on the iPad, or as any other vendor’s flash-based webviewer. The viewer actually includes a button that launches the full advanced Carestream PACS client, however for some reason this is only available when using Microsoft internet explorer.
Other devices
It would be interesting to know if the viewer performs equally well on Android tablets, however we were unable to test this. The iPhone is a no-go, it will try to use the exact same interface as on the iPad, which obviously does not fit on the iPhone’s screen.
Quirks
We found a few small quirks while using the viewer.
- First, although the interface appears tab-based, it is actually not possible to open multiple tabs or switch back to the patient list without closing the current study.
- Secondly it was not possible to put the viewer as an icon on the iPad’s homescreen. When you try that, you are presented with a browser not supported-screen upon launching it. This is a pity as it would allow for using the app fullscreen instead of wasting valuable screen space on the URL and tab bars of the Safari browser.
Conclusion
- Vue Motion is a simple and hassle-free viewer that works almost flawlessly across multiple platforms without the need to install any software or apps.
- Carestream is probably the first vendor to offer an HTML5 based medical image viewer, but we hope other vendors will follow suit.
- In its current state, it is perfectly usable for the clinician to review images remotely or on the bed-side.
Wouter Stomp is a physician from the Netherlands, currently doing a PhD in radiology. He is also an editor
