Academic institutions were among the first to adopt PACS in the ’90s. Many began by connecting a couple of digital modalities to a centralized viewing area, and then archiving the files in local storage. Volunteers from the IS department would then cobble the system together with code and cable, and somehow the whole thing worked -- at least for small-scale applications.
PACS networks became more functional as the DICOM standard matured throughout the decade and networks became more sophisticated. Then, as acquisition and capture of digital images grew, the demand for digital images began to spread beyond the radiology suite.
A similar scenario occurred at the University of California, Los Angeles School of Medicine. Here PACS didn't just take hold over the past five years; it caught fire. But the network's rapid growth made some radiologists wonder: Does increased demand for images created by a large-scale PACS increase or decrease radiologists’ workload?
In a presentation at the November RSNA meeting, UCLA RIS, PACS, and teleradiology manager Daniel Valentino talked about his ongoing research on PACS workflow problems.
Each year, Valentino and his colleagues at UCLA must deal with massive numbers of images. The group is responsible for moving more than 300,000 procedures per year across the PACS. In pediatrics alone, the archive demand was 7 terabytes (TB) of storage last year. And the load is expected to increase by 33% in the coming year, without the addition of modalities or new imaging centers, he said.
To deal with the flood of data, UCLA has implemented both commercial and in-house components to its PACS. The group deployed a high-capacity archive (the UCLA MediaStore) in November 1999 to handle the facility's archiving needs. The team also implemented an ultrasound PACS at multiple facilities, and a commercial PACS for an outpatient imaging center. The MediaStore archived more than 500 GB per month in the first quarter of 2000 and distributed over 250 GB of data daily to workstations throughout the network.
The group decided to integrate the in-house and commercial components of the PACS to enable the archive and retrieval of all images acquired at the UCLA campuses and clinics. Soft-copy reading has been the norm at the institution for the past few years, and is performed on a mix of both commercial and homegrown 1K viewing stations. Soft-copy is the sole viewing method for ultrasound images, as well as all CT and MR images acquired at outpatient imaging centers. In addition, all CT, MR, and computed radiography (CR) studies in the pediatric radiology department are read from soft-copy.
The researchers found that PACS has introduced new, labor-intensive quality-control tasks that tend to shift workload to the radiologist. Foremost among the problems identified by the group are data-entry errors introduced at the acquisition station. These are due to both human error and the DICOM interface of some modalities in the institution.
Human error is encountered when information is entered incorrectly. DICOM problems occur when some of the older digital modalities do not allow for the entry of information deemed critical by UCLA. This problem has necessitated the implementation of automatic demographic entry via bar-code scanners and the retooling of DICOM software.
Another area Valentino and his colleagues identified as adding to radiologists' workload was image quality control. As PACS took imaging out of the hands of technologists, the group found that quality control of images was being left to radiologists. This required the reviewing physician to spend more time orienting and window-leveling images, as well as selecting various kinds of image processing to better visualize a region of interest. And the facility needed to spend more time training technologists in digital-acquisition techniques than it had anticipated.
They also found sharply higher demand for viewing stations by non-radiologists. To solve the bottleneck, UCLA has implemented high-quality, low-cost paper printers to distribute images to all locations where they are needed. The institution is also looking at thin-client, Web-based distribution components as a way of resolving the increased demand for image viewing.
Valentino said that implementing a large-scale PACS has given rise to significant reliability, scalability, and maintenance problems, some of which he attributed to mixing commercial components with those developed in-house.
"I would not necessarily recommend that you embark on building your system yourself," he said. "In fact, I would definitely recommend that you pursue a commercial solution if you’re trying to tie together multiple heterogeneous imaging devices in multiple facilities."
By Jonathan S. Batchelor
AuntMinnie.com staff writer
January 19, 2001
Related Reading
DLT, MOD have different strengths in PACS storage; more choices on the way, September 19, 2000
Click here to post your comments about this story in our PACS Digital Community. Please include the headline of the article in your message.
Copyright © 2001 AuntMinnie.com
