PACS workstation vs. PC: Study finds similar diagnostic results

The proliferation of PC-based review stations prompted a recent comparison by researchers in New Zealand of the reliability of PCs verses more expensive PACS workstations.

The study (Acad Radiol 2002;9:646-653) found that PC-based systems provide results similar to those obtained with a workstation at considerably less cost, at least for evaluating computed radiographs of the hands in early rheumatoid arthritis.

The study was prompted by two concerns. One was PACS vendors' insistence that images on a standard PC can be used only for reference, not for diagnosis. Some vendors even mark such images "for reference only."

"We had already started using images displayed on PCs for clinician use and were aware that in many cases the clinician would in fact effectively use these for diagnostic purposes before receiving the radiology report," said Dr. Anthony Doyle, a clinical associate professor of radiology at the University of Auckland. "We wanted to investigate the validity and safety of that approach."

Once PACS is introduced into an enterprise, many clinicians believe they need diagnostic-quality workstations, which is not economically viable. But in many cases, they are merely using PCs inappropriately, due to simple remediable factors such as glare caused by open curtains near the monitor or incorrect image window and level settings, Doyle said.

To eliminate those issues, he designed the study so that readings were performed under optimal conditions.

"We found no significant differences in performance between the PC and workstation for interpretation of hand images in rheumatoid arthritis," he said.

This finding indicates that appropriately used PCs are an adequate diagnostic tool for viewing digital radiographic images, at least in skeletal applications, he said.

"We encourage validation of any equivocal findings using a workstation, but since doing the study, we have had very few requests for that and no instances of patient care being adversely affected by clinical use of PCs for image viewing," Doyle said.

One of the reasons PCs were believed to be effective in clinical settings was that in pre-PACS days many clinicians viewed images and made diagnoses in suboptimal circumstances, including films held up to the window or view boxes situated under bright lights.

According to Doyle, digital images viewed on a PC with the display optimized using available image tools should be as good as or better than conventional radiographs viewed in the same manner.

"Now that clinicians have become used to looking at images on PCs at proper windowing and resolution, this does in fact seem to be the case," he said.