“The present is big with the future,” observed author Rudyard Kipling. The novelist was not referring to 21st century diagnostic imaging; however, the insight certainly applies. As radiology heads into the second decade of the 21st century, imaging stakeholders will leverage molecular imaging and digital pathology to deliver personalized medicine. CT radiation dose will plummet as radiologists re-invent relationships with clinical colleagues and make sense of meaningful use. The coming years will require new levels of creativity, collaboration and communication. As 2010 draws to a close, Health Imaging & IT visited with leaders to reflect on the evolution of imaging over the next three to five years.
CT imaging: A dose of good news
For the last several years, CT vendors have battled over slice count. However, the paradigm is changing. “The good news is that phenomenal activity and innovation are taking place in this space. We need to increase diagnostic confidence in smart ways,” offers Dominic Smith, vice president, CT and nuclear medicine for Philips Healthcare. Vendors and professional societies have put a bulls-eye on CT dose and are targeting an array of dose reduction tools with research and development dollars.
Dose reduction is a massive technical challenge; traditional approaches degrade image quality and increase reconstruction time—which defeats the utility of CT as an efficient triage tool and may lead to additional scanning. With CT dose in the hot seat, vendors are striving to reduce dose to less than 3 milliseverts (mSv) and even less than 1 mSv for some studies, such as pediatric cardiac CT studies. Technical development, however, represents only part of the changing paradigm.
“Education and collaboration among governing bodies, clinicians and industry are going to be key,” says Joe Cooper, director of CT for Toshiba America Medical Systems. Evidence of industry collaboration is mounting, shares Ken Denison, global CT dose leader for GE Healthcare. Consider for example various Medical Imaging & Technology Alliance (MITA) initiatives:
- Dose Check will provide an alert to CT operators when recommended radiation dose levels—as set by the healthcare provider—will be exceeded.
- DICOM Dose Structured Report provides a standard format for sending radiation exposure information to systems such as PACS and EMRs.
- Enhanced Protocol Security, a standard still in development, will allow healthcare providers to better control access to protocols, likely through password protection, as well as provide a record of all changes.
Vendors also are working on internal system checks; the latest scanner software has the capability to identify and recommend KV and mAs settings based on patient size and exam type. Such scan protocol optimization is an example of decision support prior to scanning, says Christian Eusemann, director, CT clinical research and development for Siemens Healthcare.
New technical developments also hone in on image reconstruction. Vendors are improving on earlier models with techniques and reconstruction algorithms to cut dose and maintain or improve image quality. Universal reconstruction algorithms that apply to all CT studies could slash dose for many studies to less than 3 mSv.
Finally, radiologists will play a key role and could assist with increased efforts to educate referring clinicians about low-dose ordering. For example, when a radiologist receives an order for a chest CT to rule out nodules, he can continue with a low-dose scan. A general chest CT requires a higher dose. “It remains to be seen how the radiologist’s role will evolve. Radiologists may prescribe how much dose is necessary for CT scanning,” suggests Cooper.
Most insiders agree that the heightened focus on dose will have a nominal impact on CT utilization. “CT will remain a diagnostic modality of choice for many clinical questions,” says Eusemann. As CT vendors solve the dose problem, they can focus on other developments.
“We’ll see a drive toward quantifiable CT over the next few years,” shares Smith. Upcoming developments will detect and differentiate tissue density for increasingly accurate and lower dose imaging. Such advances are welcome as are ongoing developments in molecular imaging and personalized medicine.