RSNA News - December 2004

iPod Helps Radiologists Manage Medical Images

Technology coming from the consumer market is changing the way we do things in the radiology department.
— Osman Ratib, M.D., Ph.D.

The iPod is not just for music any more. Radiologists from the University of California, Los Angeles (UCLA), and their colleagues at other institutions from as far away as Europe and Australia are now using iPod devices to store medical images.

"This is what we call using off the shelf, consumer market technology," says Osman Ratib, M.D., Ph.D., professor and vice-chairman of radiologic services at UCLA. "Technology coming from the consumer market is changing the way we do things in the radiology department."

Dr. Ratib and Antoine Rosset, M.D., a radiologist in Geneva, Switzerland, recently developed OsiriX, Macintosh-based software for display and manipulation of complex medical image data.

"We chose to do it on the Macintosh because of the high performance of Mac graphics," Dr. Ratib says. "The purpose is to be able to quickly and interactively manipulate very large data sets in 3D, 4D and even 5D. It's amazing how much performance we get."

How did the developers go from a music player to a medical storage device? "We basically wanted something that everybody could use," explains Dr. Ratib. "That's why OsiriX can be used with the iPod, iChat and other tools."

"Radiologists deal with a very large amount of medical imaging data," Dr. Ratib explains. "I never have enough space on my disk, no matter how big my disk is—I always need more space. One day I realized, I have an iPod that has 40 gigabytes of storage on it. It's twice as big as my disk on my laptop and I'm using only 10 percent of it for my music. So, why don't I use it as a hard disk for storing medical images?"

Dr. Rosset set up the OsiriX software to automatically recognize and search for medical images on the iPod. When it detects the images, they automatically appear on the list of image data available—similar to the way music files are accessible by the iTune music application.

"It's easy to use and you don't have to worry about how to load and unload it from the iPod," Dr. Ratib says. "But the real beauty of it is that I can use the images directly on the iPod. I don't have to take the time to copy them to my computer. The iPod allows me to copy data from work to my laptop, but I don't have to do it if I don't want to."

Dr. Ratib sees the iPod as a kind of giant memory stick, "The performance is amazing."

Large data sets can be transferred directly to the iPod through the firewire connection. "I use my software to download images from the PACS or from any imaging source," Dr. Ratib says. "OsiriX follows the most universal way of accessing any image and it covers virtually every DICOM format possible. It's very, very flexible."

Once the images are on the iPod, they can be carried from one machine to another, as long as the computer is a Macintosh. "You can see the images and display them as you would do with any other file that's on your hard disk," Dr. Ratib says.

OsiriX allows users to upload images to the Internet. It also supports iChat instant messaging, which is compatible with AOL instant messaging. This allows the user to take advantage of the video-conferencing capability. But instead of seeing the user's face on a Webcam, it is modified to show the user's screen at the other end of the conversation.

"For us, it's a way of doing very cheap, very convenient teleradiology," Dr. Ratib explains. "I could be chatting with one of my buddies and he can see my screen, so I can show him what I'm doing with an image."

"I can also send him that image at high resolution as an attachment," he continues. "He'll immediately receive it, open it and we can continue to talk about it."

The software is free, distributed under Open Source Licensing, and has found users around the world. "I want everybody to participate," Dr. Ratib says.

A recent survey of OsiriX users found that it has been very well received. One thousand people downloaded the software within the first month of distribution. Dr. Ratib believes actual usage is about three to five times that number.

Among the respondents to the survey, more than one quarter of the OsiriX users were radiologists, half of them at university hospitals. Forty-one percent of the total survey respondents said they use OsiriX daily, while 46 percent use it weekly. The most frequent usage was for research (53 percent), followed by presentations (37 percent), PACS at home (34 percent), PACS at work (29 percent), 3D station (26 percent) and fun (24 percent).

Free Software Download

OsiriX software can be downloaded at homepage.mac.com/rossetantoine/osirix/.

The software was featured at RSNA 2004 on 30-inch, high-definition color screens during two presentations in the infoRAD area. The presentations were titled, "OsiriX: Multimodality Open Source Image Display and Navigation Software," and "Navigating the Fifth Dimension—Innovative Interface for Multidimensional Multimodality Image Navigation."

OsiriX was also featured in the scientific poster, "Merging Imaging Modalities: Practical Applications," and in the scientific paper, "Display and Interpretation of Multidimensional and Multimodality Images."

"We're not trying to reinvent something that's completely different," Dr. Ratib concludes. "We're trying to adapt to the very rapidly changing environment, and provide ourselves with tools that industry would take years to give us."

The authors of the Osirix Software, Osman Ratib, M.D., Ph.D. (front), and Antoine Rosset, M.D. (back), review images stored on the iPod portable device.

This teleradiology setting shows an inserted live video image (upper right corner of the screen) of a videoconference session using iChat software for instant messaging that is available on all Macintosh platforms.

Images courtesy of Osman Ratib, M.D., Ph.D.