In the daily chaos that is the US health care system, there are but three elements that matter: patients, caregivers, and medical technology. Two orders of technology figure in medical imaging. The first creates the images for diagnostic or interventional purposes, and the second processes images and supports their interpretation for patient care. First-order technology encompasses the amazing image-acquisition devices that line the exhibit halls of the annual meeting of the Radiological Society of North America: machines for CT, direct radiography, computed radiography, MRI, and positron-emission tomography.
In the second-order category reside dictation devices and systems, picture archiving and communications systems (PACS), teleradiology equipment, and information systems. Often referred to as enabling, such technology increases process efficiency. Without the first-order creation of the image, it can be argued, the second-order delivery of medical services based on the image is irrelevant. Among second-order medical imaging services, however, PACS, in particular, holds the promise of becoming (and becoming recognized as) a first-order technology, every bit as important for improving care as the most advanced imaging equipment.
|The pre-picture archiving and communications system (PACS) and post-PACS effect on different image and report efficiency variables at an urgent care center located at the Mayo Medical Center, Rochester, Minn. Adapted from J Digit Imaging.|
PACS-enabled radiology group, imaging center, or hospital should have a better quality of results than facilities without PACS. Such a hypothesis could be investigated by comparing general patient care at the same facility before and after PACS installation. Indeed, such comparisons have been made (specifically concerning productivity and report-turnaround time) to document increases in efficiency resulting from PACS installation. If such before-and-after comparisons were performed to relate PACS installations to patient care, increased efficiency would certainly be one reason for the improvements seen in the postinstallation environment. Faster turnaround times should mean more timely diagnoses and treatments. The information richness of the collaboration between radiologists and referring physicians in a PACS-enabled environment is another factor likely to contribute to improved care. It is also the case that a PACS installation of the right scope can serve as the necessary foundation for using (and affording) the latest advances in imaging modalities. Without the PACS infrastructure, these advanced devices, such as the electron-beam CT scanner and the high-field open MRI unit, could be much harder to acquire and operate.
PACS AND PRODUCTIVITY
It is well documented in the peer-reviewed literature1-6 that PACS installations improve radiologist productivity and report-turnaround time. There is no uniformity in the kinds of positive results presented in the literature, but a review of three recent studies, differently conceived and from different institutions, can help to guide expectations. Mattern et al1 prospectively compared image and report availability times in a busy urgent care center at the Mayo Clinic, Rochester, Minnesota, during film-based practice and after the installation of a PACS. During the two times of measurement, basic practice patterns remained the same. The figure on page 3 depicts the dramatic improvements seen in interpretation and image-delivery times for a number of different parameters. On average, in the PACS environment, referring physicians received the diagnostic images for viewing more than 3 hours sooner than they had before installation of the PACS.
Gale et al2 compared the efficiency of a PACS enhanced by an automated dialog-box user interface with both a conventional PACSwork-list user interface and conventional hard-copy interpretation on a viewbox. The dialog box, developed by eMed Technologies, Lexington, Mass, consolidated a series of commands for automated work-list and image display into a single mouse click. In this study, three radiologists at the Veterans Administration Boston Health Care System interpreted the same chest films using one of the three methods on a rotating basis over 12 consecutive days. The investigators found that both PACS methods significantly decreased the mean interpretation time, compared with hard copy. The addition of a dialog box for automated image display, however, also significantly decreased the mean interpretation time, compared with the conventional PACSwork-list interface and hard copy.
Reiner et al3 performed time-and-motion analysis on four board-certified radiologists for 100 CT examinations, with the objective of determining the total time required to display, interpret, and dictate the individual findings of CT using conventional hard-copy interpretation on a viewbox versus soft-copy interpretation at a four-monitor high-resolution workstation. The site of this study was the Baltimore Veterans Administration Hospital. The analysis found a 16.2% reduction in the overall time for soft-copy interpretation compared with hard-copy interpretation.
Besides supporting faster turnaround, a PACS environment can enhance the information richness of the dialogue between radiologists and referring physicians. A radiology report mediated by a PACS delivers to referring physicians not just interpretation, but also key images; not just the most recent images but, if necessary, prior images to be used for comparative purposes.
Moreover, if the PACS has an Internet component, the interpretation and images are accessible to physicians at any time and in any place. This enhanced communication between the radiologist and the referring physician, owing to PACS, makes the relationship between the parties collaborative and consultative. The radiologist thus becomes more integrated into clinical management decisions.
Since the radiologist is best qualified to recommend an efficient imaging work-up for a given clinical question, increased collaboration before the scheduling of an examination, or even during an examination, can improve outcomes while lowering costs. The information richness provided by PACS also improves the dialogue between radiologists. Colleagues can discuss interpretation from any workstation or any computer, depending upon the systems that they have available.
NEW MODALITIES AND SUBSPECIALTIES
The greater efficiency afforded by PACS means that patient throughput for a new imaging modality can be faster. If the daily break-even number of examinations for high-field open MRI is a given number of patients per day, for example, a PACS environment can facilitate the achievement of that number of examinations.
Often, it is not economically feasible for a group, center, or hospital to provide subspecialty radiology services, since a single facility cannot generate sufficient volume to justify the subspecialty dedication of individual radiologists and the acquisition of appropriate imaging devices. With the right PACS installation, however, outlying facilities can direct images to those radiologists best qualified to interpret the results of specific subspecialty examinations. PACS maximizes the quality of image interpretation by transferring images to the radiologists best trained to deal with the specific imaging modality or disease process.
John Mesevage is a freelance medical writer.
- Mattern CWT, King BF Jr, Hangiandreou NJ, et al. Electronic imaging impact on image and report turnaround times. J Digit Imaging. 1999;12:155-159.
- Gale DR, Gale ME, Schwartz RK, Muse VV, Walker RE. An automated PACS workstation interface: a timesaving enhancement. AJR Am J Roentgenol. 2000;174:33-36.
- Reiner BI, Siegel EL, Hooper FJ, Pomerantz S, Dahlke A, Rallis D. Radiologists? productivity in the interpretation of CT scans: a comparison of PACS with conventional film. AJR Am J Roentgenol. 2001;176:861-864.
- Twair AA, Torreggiani WC, Mahmud SM, Ramesh N, Hogan B. Significant savings in radiologic report turnaround time after implementation of a complete picture archiving and communication system (PACS). J Digit Imaging. 2000;13:175-177.
- Tamm EP, Raval B, West OC, Dinwiddie S, Holmes R. Evaluating the impact of workstation usage on radiology report times in the initial 6 months following installation. J Digit Imaging. 1999;12:152-154.
- Mehta A, Dreyer K, Boland G, Frank M. Do picture archiving and communication systems improve report turnaround times? J Digit Imaging. 2000;13:105-107.