Anna K. Chacko, MD

This article was originally designed to discuss the implementation of digital radiographyspecifically CRat the Lahey Clinic. While CR is a key to success, achieving success is not as simple as the installation of CR devices. Success requires a thorough understanding of the problems that beset an extremely busy, film-based radiology department and then devising a fundamental paradigm shift that would make success permanent.

A wag, or maybe a wise man, once said, Time can be only stolen, and the only gift of value is time. Where and how does one steal time?

As a species, we spend inordinate amounts of time in procuring, acquiring, and transmitting information. The time spent in the acquisition and transmission of information is time wasted. Processes that free time up for pursuit of other endeavors are bound to be more valuable than those that do not.

Radiology as an enterprise is rife with possibilities for providing the gift of time by improving access to our product and giving our customers timeour customers being patients who require imaging and clinicians who request interpretations and consultation.

Almost 3 years ago, radiology was the bane of our institution. It was not uncommon to have a patient waiting for more than 6 hours to be imaged and well over 2 days to get the final reading out to the referring doctor. Our waiting rooms were overflowing with disgruntled patients and our phones rang with angry referring clinicians. The logjam in radiology prevented the delivery of the high-quality, efficient, and timely care that our institution has prided itself on for more than 75 years.

While it was obvious that technology would provide some relief, we believed that the relief would be neither complete nor permanent. A team was configured in conventional radiography to tackle the issue. This was headed by the chief technologist in the section, supported by several of her staff.? The effort was configured and guided by our director of digital imaging, whose expertise in engineering management provided the necessary critical thinking and analytical skills.

The general process sequence devised by the digital imaging team incorporated the following steps:

  1. Identify core processes
  2. Identify key customers and requirements
  3. Define problem/s
  4. Declare charter
  5. Map process
  6. Measure current performance
  7. Prioritize, analyze, and implement
  8. Expand and integrate


We decided to tackle the thorniest of our problems: the orthopedic surgeons and their patients. We defined the problem: the wait times for final delivery of our product were unacceptable. We then set ourselves goals that would benchmark success. Our goal was to deliver images to the orthopedic surgeons in 30 minutes.

With painstaking precision, fortitude, and focus, process maps were devised, which tracked patients every 15 minutes. This allowed us to delineate the bottleneckswhich we set to work to eliminateand identify opportunities to improve process. The final step was the insertion of new technology to facilitate the digital acquisition of images and electronic transmission of the productie, the image and the report to the clinician.This led to the exploration and deployment of several different configurations of computed radiography devices.

The models by which conventional radiography needs are addressed in our institution, as in most hospitals, are as follows:

  1. Patients are brought to the acquisition device. In our hospitals, the conventional radiography area, which fits the first model, is divided up into pods.
  2. The acquisition device is brought to the patients, the operating rooms, and the intensive care units. At Lahey Clinic Hospital system, we have the Post-Anesthesia Care Unit, the Surgical Intensive Care Units (SICUs), the Medical Intensive Care Units, and the Coronary Care Units (CCUs).

Our selection of CR devices was based on how best to achieve our goals of promptness and expediency with both models. The kinds of CR devices selected were the following:

  1. Cassette reader with distributed registration
  2. Single plate reader
  3. Integrated CR changer and generator


Cassette reader with distributed registration. We acquired an integrated CR network to support two separate work centers (pod 1 and pod 3). Pod 1 has four radiography rooms supported by two readers. The readers are linked to four registration stations. The CR cassettes can be registered on any of the registration centers and read on either scanner. The image is then transmitted to the center on which it was registered, in order for the technologist to quality control the study. There is a third scanner and an additional registration center located in the fluoroscopy work core, pod 3. This station is also networked with the two scanners in pod 1, providing redundancy for pod 3 while maintaining quality control. The stations are also networked to a primary and a backup dry laser printer. This arrangement provides a redundant imaging network for these two work cores, in which the loss of any single printer or CR reader does not seriously affect the work flow.

Integrated CR changer and generator (speed suite). Pod 1 has two rooms that use cassetteless CR. One of the rooms has a dedicated chest changer, and the other room has a dedicated CR reader built into the table. The table unit is used primarily for emergency cases. This room also has a wall bucky, in which CR cassettes are exposed. These integrated rooms have the same registration station user interface that is used for the cassette-based systems.

We selected single plate readers to fit the second model of work flow:

Single plate reader. The single plate readers are linked to only one registration station. They are used in areas away from main radiology, mostly in conjunction with portable x-ray. These units have been installed in the emergency department, SICUs, CCUs, and operating room area. Cassettes can be read near the area in which the image was obtained, and a decision on whether a retake is needed can be made on the spot. The image can then be transmitted to the picture archiving and communications system (PACS), and be made available on PACS workstations in the care area. Without these readers in remote locations, the tech would have to bring the cassette back to the main radiology core to be read, and then have to go back to the remote area if a retake was necessary.


Additional technology features, which helped us achieve our goal, included the following:

  • DICOM Modality Worklist (MWL)
  • Procedure Code Mapping

DICOM Modality Worklist. All of the registration station computers have DICOM Modality Worklist software. This DICOM feature is essential for smooth work flow in the department. The station queries the PACS database for the patient and study information. The worklist query can be configured to return a filtered general list (such as all CR studies scheduled for today), or to return a patient-based list. We use the patient-based list, which returns information for only the individual study. This query is initiated by scanning the bar code of the study accession number that is printed out from the radiology information system.

Procedure Code Mapping. The worklist query also returns the procedure code for each study. The registration station is programmed with a table that relates the procedure code to the radiographic projections that are obtained for each procedure and to the anatomy-specific image processing that will be applied to each projection. For example, a PA/LAT chest study will be automatically set up with two entries: one for the PA image and one for the LAT image. The cassetteless rooms expand on this feature. The registration stations for these rooms control the x-ray generators through a serial interface. In addition to setting up the image processing parameters for each projection, they also feed the default technique (kVp, mAs, and image receptor size) to the generator and bucky.

We are in the process of completing the incorporation of a digital radiography device into our work-flow solution. Whether this will address our needs and provide the same degree of radiologist and technologist acceptance remains to be seen.


In summary, we have achieved our goals of reducing waiting times for patients and referring clinicians. We are gratified to report that our average wait time is now 22 minutes from the time of arrival of the patient to departure. By the time the patient wends his way back to the referring doctor, the image has already arrived at the doctor’s desktop.

While technology provides a critical portion of our solution, it is essential to recognize that unless the problem is identified, the process mapped, and the goal set, technology will merely provide window dressing without effecting real change. Without technology, the rest of the process will not achieve the final goal.

In radiology, we are destined to see Darwinian, evolutionary changes, in which old technology and processes are replaced by endeavors that provide value, saving that most precious commodity, time. Digital radiography in general and computed radiography in particular will be the spearhead of one such tectonic shift in radiology. However, the spearhead is of little value without the spear and the power behind itie, a fundamental change of process.

Anna K. Chacko, MD, is the chairman of radiology

John Weiser, PhD, is a consultant with Xtria, Frederick, Md.

Thomas R. Shook, MBA, is director of radiology

Lorraine D. Kelly is clinical delivery process manager, chief technologist at the Lahey Clinic, Burlington, Mass.