Digital Imaging and Communications in Medicine (DICOM)

13.6 From PACS to PDAs? 293
images of interest in compressed multimedia formats (JPEG for still images,
MP3 and AVI for videos), readily presenting them to the viewer.
2. Reliability. Because conventional computers and handhelds are used primarily
as thin clients (that is, for display purposes only), the issue of reliable
data storage is passed by. Encryption is built into all contemporary
networking protocols (wireless included), and various security software is
available for personal computers and storage. Also, because personal devices
(unlike PACS workstations) are rarely shared, they are less prone to
security leaks.
3. Image viewing quality. Current advances in conventional monitors and
graphics cards (resolution and color depth) have made them extremely competitive
and increased their use in PACS setups. As an example, consider
supporting more than 8 bits (256 shades) per color channel. Previously, you
would have needed a special radiological card to support a 10-bit or 12-bit
grayscale. Now, many high-end, consumer-level graphics cards support rich
color display and become more frequently used in digital medicine. Unlike
computers, PDAs and cell phones are not positioned as primary reading
devices; their display quality is indeed inferior for the needs of most current
diagnostic tasks. 47 However, PDAs are excellent for quick, real-time
reviews, sharing teaching cases, sending and displaying images to referring
physicians, and so on. These radiology applications become increasingly
important and the ability to do them on the fly can substantially improve
radiological workflow.
4. Convenience. This aspect is commonly overlooked by technical analysis,
while it becomes dominant in many cases. If radiologists, just like any other
consumer, use plain, conventional monitors, computers, and handhelds for
most of their day-to-day tasks (checking emails, writing presentations, doing
teleradiology), they would also tend to use them for digital imaging.
People are always more productive and comfortable with something they
are used to; switching between different systems or even interfaces is always
awkward.
5. Role in healthcare. Light units such as PDAs are already routinely used in
the other healthcare applications; for example, electronic health records,
patient registration, tracking, reporting, dictation (cell phones). Therefore,
adding image data to mobile devices comes very naturally and, when provided,
is immediately appreciated by physicians.
6. Processing power. With little doubt, large systems can offer more processing
power and more memory, making many computational tasks real time.
However, beefed-up hardware is often used to compensate for inefficient
software implementations. Easily 90% of contemporary digital imaging
47 Nevertheless, even now the spatial resolution of current PDAs approaches that
of certain modalities such as MR and ultrasound (around 300 pixels in image height
and width). PDA color (or grayscale) depth is not yet sufficient.