Design Requirements for Radiology Workstations

Abstract

This article stresses the importance of capturing feedback from representative users in the early stages of product development. We present our solution to producing quality requirement specifications for radiology workstations, specifications that remain valid over time because we successfully anticipated the industry trends and the user’s needs. We present the results from a user study performed in December 1999 in a radiology clinic equipped with state-of-the-art Picture Archiving and Communications Systems (PACS) and imaging scanners. The study involved eight radiologists who answered questions and provided comments on three complementary research topics. First, we asked our subjects to enumerate the advantages and the disadvantages for both softcopy and hardcopy reading. We identified the two major factors for productivity improvement through the use of PACS workstations: workflow re-engineering and process automation. Second, we collected radiologist feedback on the use of hanging protocols (HPs). The results indicated the high importance of automatic image organization through HPs, with the potential effect of reducing the interpretation time by 10–20%. Our subjects estimated that 10–15 HPs would cover about 85%–95% of the regular radiological examinations. Third, we investigated the impact of the display devices on the radiologist’s workflow. Our results indicated that the number and the properties of the monitors is a modality-specific requirement. The main results from this study on key functional requirements for softcopy interpretation only recently were incorporated in most of the current, successful PACS workstations.

APPENDIX: USER QUESTIONNAIRE

Hardcopy versus Softcopy

Please use Table 9 for questions 1–4:

• 1. How many computer image-viewers did you use and for how long?

• 2. Productivity: How many studies do you review per day? Each row signifies a typical day.

• 3. Quality of the diagnosis: Which mode do you think is more accurate and why (use <, = and > between columns).

Table 9 Productivity, Quality of Diagnosis, and Time Spent Arranging the Study (%)

What fraction of the Table 10 for questions 5–7.

• 4. What are the major drawbacks of each mode?

Table 10 Present Drawbacks, Most Used Features, and Proposed New Features

• Example: (I) Small screen size; (II) lack of detail in context; (III) reduced resolution; (IV) reduced productivity; (V) personal preference.

• 5. What are the most used features?

• Example: (1) Window/Level; (2) Zoom; (3) Pan; (4) Magnifying glass; (5) Cine play; (6) use previous studies for comparison; (7) linking series in stack mode.

• 6. What would be the most important features that you would want to have?

• Example: (a) Duplicate instances of a series with different W/L settings; (b) Hounsefield measurement on CT images; (c) enhanced printing capabilities; (d) enhanced mark & measure capabilities; (e) display healthy study example.

Viewing Protocols

We propose implementing a viewing protocol like a collection of predefined settings (W/L, zoom, rotation, arrangement of the series in the viewports) that the system uses to display the images upon loading a study for review. It would be used to reduce the time spent preparing a study for review. A viewing protocol template could be defined for each type of study, using a hierarchical architecture similar to the one presented in Table 11.

Table 11 Hierarchical HP Organization

For plain film studies, such as CR, DR, and X-rays, you would most likely define protocols at the study level, where the same settings are used for all series in the study. These protocols contain general parameters such as the initial layout, viewing mode (stack or tile).

For cross-sectional studies, such as MR and CT, you may want to define protocols at the series level so that you can define the number of series within the study and then set the parameters, such as the window settings and orientation, for each series separately.

• 1. What other user preference (such as size and color of annotations, user-specific W/L settings) should be stored in the viewing protocols and how important do you consider this feature for each modality? Please write your suggestions in Table 12.

Table 12 Proposed New Features Versus Importance

For the following two questions, please write your answer in Table 13. If templates for viewing preferences were to be defined (like “MRI of right knee without contrast”):

• 2. How many do you think you will need?

• 3. What percentage of studies do you think will fit in these templates (requiring minimal/no further adjustment)?

Table 13 Templates

Displaying Images

• 4. How important is the resolution (1728 × 2304 versus 2048 × 2560)?

• Size versus resolution: show different images (from different modalities) at different layouts (7 × 9 MRI images fit in 1728 × 2304; they prefer a 2 × 2 layout, stack mode).

• 5. What is the preferred number of monitors for each resolution?

• 6. Would you prefer a single big monitor instead of several smaller ones (“frame effect”)?

• 7. How are these preferences dependent on the modality?

• 8. Which modality do you think best fits for each mode?

• 9. Can you fit all of the image into a single Multi-Modality viewer?

Moise A, Atkins MS: Workflow Oriented Hanging Protocols for Radiology Workstation. Proc SPIE 4685:189-199, 2002