High-speed multidetector CT scanners are a marvel of technology, producing unbelievably detailed images of anatomic structures, yet they have created some large challenges in workflow for busy radiology and cardiology practices. Users on the cutting edge have utilized the best solutions the manufacturers have developed and devised methods to insure appropriate image renderings that facilitate clinical care and enable efficient image management and storage. A team approach of highly skilled imaging professionals facilitates the entire process.
The imaging chain that includes acquisition to post processing and interpretation to storage and archiving raises issues that must be addressed.
Jason Cole, MD, MSc, a cardiologist with Cardiology Associates in Mobile, Ala., has been using the GE Healthcare LightSpeed VCT 64-slice scanner since April to accomplish a total of 500 to 600 scans, 90 percent of which are cardiac studies. They use beta-blockers for those patients who need them, and then run three quick scans, one for calcium scoring, one test bolus and then one with contrast.
Their highly experienced technologist processes the raw data and then creates formatted images of the coronary arteries. They have customized their workstation screen so that Cole can read the raw axial data for an overview, and then perform an integrated reading that incorporates both the volumetric and cross-sectional images.
"The images that provide the ultimate diagnosis are MIP (Maximum Intensity Pixel) images," says Cole. He reviews two-dimensional MIP images with a certain number of slices that the computer formats into the best longitudinal section for each area along the vessel. He correlates the cross-sectional view with the longitudinal view. "The longitudinal view is the one that most cardiologists would be most comfortable with because it's the closest approximation of what we would be looking at in a cath lab."
They store the raw data as well as any formatted views of individual vessels in their archive for future needs. Additionally, they save a "snapshot" image of either the curved reformatted or the MIP data or any portion of the exam that has raised concern.
Because the GE workstation provides the capability for color mapping, Cole finds benefit in setting the color code to soft plaque, calcified plaque and contrast to help identify suspicious lesions. The color diagram of the entire vessel provides the curved reformatted images.
Cole explains that in reading a study there are literally thousands of images he might review for each patient. As he looks at curved reformatted views and rotates through 180 degrees tracing down the longitudinal study of the vessel, there would be no way to save all of those individual images. That's why the "snapshot" version serves to save the specific areas of interest that raised concerns.
Once the imaging exam is completed, a standardized reporting system is used to document findings of either soft plaque or potentially obstructive plaque in each section of every major vessel. In addition, typically they record a paragraph that summarizes all of the findings that is added to the standardized reporting form.
Automation and integration
Pedro J. Diaz, PhD, vice chairman of radiology at MetroHealth Medical Center in Cleveland, describes the use of their 64-channel system to accomplish a variety of imaging studies. They have worked to integrate their Philips Medical Systems Brilliance CT and their disparate information systems, including an electronic medical record (EMR), PACS and hospital information system and radiology information system (which are all from different vendors) by taking advantage of the open architecture Philips offers as native inside their CT application.
In the past, the CT scanner was just a device that you set up for scanning to acquire images, explains Diaz. As they entered the digital environment where the technologist might need to download patient information from the HIS/RIS, review lab results from the EMR and plan the imaging study, integration became a key element in managing all of these systems.
He says that their Brilliance Workspace has incorporated the capabilities of a remote workstation into the scanner itself. Automatic reconstructions of image data sets produce additional views.
"If we know we're doing a spine protocol and we need to generate sagittal slices from the axial data, we can program that up front," Diaz explains. When the technologist