**7. Digital imaging and clinical workflow**

## **7.1 Clinical workflow**

Digital mammography has transformed our everyday working environment. For many, gone are the days of darkrooms with wet chemical processing and the challenges associated with them. Film screen mammography view boxes are being used less each day as softcopy display becomes more familiar to the radiologist. Digital mammography images can be viewed from anywhere, and the trend for comparisons to be on softcopy is becoming apparent. Also, with prior studies being in digital format, the number of lost or missing priors has decreased. Files rooms with overcrowded shelves and stacks of folders piled on the floor are starting to disappear as picture archiving systems (PACS) with electronic storage are used.

Digital mammography has also had a large impact on patient throughput. Technologist image acquisition and processing time with direct radiography (DR) digital mammography has been significantly decreased in both screening and diagnostic mammography (Berns, 2006; Kuzmiak, 2010). In the DR FFDM digital screening study by Berns et al., they studied the timed comparison of 183 hard-copy SFM cases and 181 FFDM softcopy display cases. Their results demonstrated a 7.5 min/case (35%) time savings over SFM (Berns et al., 2006).

Results were similar in the diagnostic timed mammography study by Kuzmiak et al. (Kuzmiak et al., 2010). This prospective study consisted of 3 phases: 1st Phase, 100 patients imaged with SFM; 2nd Phase, 100 patients imaged on DR FFDM and interpreted on a recently installed softcopy display mammography system; 3rd Phase, same as 2nd Phase but 3-months after installation of the softcopy display system. Their results showed the

Digital Mammography 111

Digital mammography decouples the process of image acquisition, processing and display so that each component can be optimized. The digital format has allowed the development of additional software to aid the radiologist in lesion detection – computed aided detection. We are now able to view mammography images and interpret them from other clinical sites in different parts of the city, state, or country through televideo. Other emerging technologies such as three dimensional tomosynthesis are now entering clinical use. Digital technology has changed mammography over the last decade, and it will continue to change it for decades to come. It will be interesting to see what the future holds for our patients and

Dr. Kuzmiak is grateful for the inspiration and guidance provided over the years by her friend and colleague, Etta Pisano, MD. She would like to express her gratitude to Martin Yaffe, PhD, and Elodia Cole, MS, for their clinical insights and outstanding work. Finally, she would also like to thank Shiela Kuzmiak for the many hours of support during this

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**8. Conclusion** 

**9. Acknowledgement** 

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**10. References** 

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diagnostic mammographic acquisition times with processing were 13.02 min/case for SFM (Phase 1), 8.16 min/case for digital (Phase 2), and 10.66 min/case for digital (Phase 3). All phases also included the measured time for additional imaging that was requested by the interpreting study radiologists. Compared to SFM, acquisition time for Phase 2 and 3 digital were significantly less (P < .001 and P < .0001, respectively). For Phase 2 & 3 digital, there was a 4.86 min/case (37.3%) and 2.36 min/case (18.1%) time savings compared to SFM (Kuzmiak et al., 2010).

Regardless of reason for the mammogram, the main reason for the time savings is the elimination of processing time with DR mammography. The technologist no longer has to leave the exam room with SF cassettes to develop. With SFM, each film takes approximately 90 seconds to develop. This time is now saved. The technologist now can review the images on a 1-megapixal monitor after exposure while the patient is still in the room. After initial review by the technologist for positioning and technique, the images are sent to PACS with a push of a button or touch of a screen.

As part of the clinical workflow, there has been the concern of radiologist interpretation time with digital mammography. Berns et al. published average interpretation times, interpreted by seven radiologists, for their screening study of 1.2 minutes for SFM and 2.0 minutes for DR FFDM (Berns et al., 2006). Study results by Haygood et al. showed similar results in longer interpretation times with digital (Haygood et al., 2009). Haygood's study included 4 radiologists who were timed in clinical interpretation of 457 screening mammograms consisting of 189 SFM and 268 digital mammograms. They reported increased interpretation times for digital ranging from 1.27 to 3.37 minutes. The average interpretation time for all readers for SFM was 2.12 minutes and 4.0 minutes for digital (Haygood et al., 2009).

In contrast to the above screening studies, Kuzmiak et al. found the radiologist interpretation time for digital mammography on softcopy display was not significantly different from that for film mammography in a diagnostic mammography setting (*P* = .2853 and *P* = .2893, respectively) (Kuzmiak et al., 2010). The mean interpretation times were 3.75 min/case for screen film (Phase 1), 2.14 min/case for digital (Phase 2), and 2.26 min/case for digital (Phase 3). The results provide support to radiologists for conversion to direct radiographic digital mammography for clinical use and that radiologists planning on using softcopy display systems must have appropriate training to optimize throughput. In addition, softcopy display manufacturers should continue to improve the functionality and ergonomics of their products to make softcopy interpretation more efficient.

#### **7.2 Electronically generated report**

With softcopy display systems an electronically generated reporting system can be integrated with it. Numerous vendors are available and each has different functions depending on radiologist preference. With these systems, mammograms and other imaging reports can be dictated (generated) and electronically signed off. Thus, it decreases the time from the initiation of the patient's exam to the exchange of information to the patient's referring physician.
