Enabling Next-Generation CT Angiography

CT angiography (CTA) represents a tremendous leap forward in diagnostic imaging. It, together with magnetic resonance angiography, is increasingly becoming the diagnostic imaging solution of choice. Clinically relevant and workflow efficient results, however, hinge on sophisticated software as well as a state-of-the-art CT scanning solution.

In fact, Barry Stein, MD, FSIR, interventional radiologist and director of the division of cardiovascular MRI & CT and advanced imaging analysis & 3D laboratory at Hartford Hospital and Jefferson Radiology in Hartford, Conn., opines, “The critical element of a busy vascular program is accurate, efficient, easy-to-use software that generates clinically pertinent information to drive patient care. GE Healthcare’s Advantage Workstation (AW) VolumeShare2 advanced image visualization and analysis tool meets these needs and enables me to interpret a CTA with thousands of images very quickly and accurately.”

Stein relies on the software’s VesselIQ Xpress application and Autobone Xpress technology for automatic segmentation of bony structures in the head, neck, abdomen and lower extremities to help accurately and easily identify and analyze vessels, including the removal of calcium. The software overcomes the primary clinical and workflow challenges of CT angiography, enabling facilities to effortlessly implement the procedure to improve patient care and enhance workflow.

Overcoming the challenges

CT angiography is ripe with promise and potential, but implementing it in clinical practice can be challenging. CTA generates an image dataset in the 2,000 to 3,000 image range. The radiologist needs a helping hand — advanced image visualization and analysis software. “VolumeShare2 with VesselIQ Xpress enables the organization of the data in a format that lets me evaluate thousands of images within a few minutes to garner all the information critical to making an accurate and relevant clinical diagnosis. As importantly, it enables me to make appropriate therapeutic decisions,” sums Stein. In other words, VesselIQ Xpress transforms 64-slice CT into a clinically relevant and workflow efficient solution.

Stein likens VolumeShare2 to driving across the country with a detailed map. Without a map, a driver can get lost, wind up in a bad neighborhood or get sidetracked by detours. “Doing a CTA prior to endovascular or surgical therapy provides the anatomical and topographical detail of what one can expect to encounter so planning can occur appropriately. Without this software capability it could take hours to evaluate the anatomy in any reasonable, clinically relevant manner. VesselIQ Xpress provides one-click bone removal and center-line measurements for stenosis quantification and all measurements for stent graft planning. In five to 10 minutes, the package accurately and efficiently garners a wealth of critical clinical information.”

Unfortunately, the large volume of image data is not the sole challenge associated with CT angiography. Bone removal can be a time-consuming and tedious process. Manual or semi-automated bone removal is not time effective. VolumeShare2 with VesselIQ Xpress expedites and simplifies this task. “I just launch the application, and the bones are extracted, revealing the blood vessels without being obscured from adjacent bones or other dense structures,” explains Stein.

Another imaging challenge is visualization of the vessel lumen. Radiologists and vascular specialists need to determine whether the lumen is open or blocked. Traditionally it has been a difficult process to make an accurate and confident assessment without vessel analysis software. VesselIQ Xpress automatically generates center-line measurements through the blood vessels of interest, enabling interrogation of the lumen and wall of the vessel in an infinite number of orientations. This comprehensive approach allows the user to accurately and quickly evaluate patency or degree of vessel stenosis, says Stein.

CT angiography has transformed endovascular planning and management for aneurysms, too. The conventional treatment entailed open and extensive surgery. It has now become standard of care for interventionalists to deploy stent grafts to isolate the aneurysm using minimally invasive techniques. The hitch is the degree of planning required prior to placing the stent graft. “These procedures are fairly complex and require detailed planning,” Stein says. “We typically encounter various sizes and differently contoured anatomy. The vessel analysis package allows us to evaluate the aneurysm for the planning and procure the necessary measurements very accurately, very quickly and very easily.” 

Conclusion

CT angiography promises to improve patient care. The primary challenge is to implement the procedure in a way that meets the dual, and often conflicting, needs of 21st century radiology practices — enhanced clinical care and workflow efficiency. GE’s VolumeShare2 delivers these results by providing the tools necessary to expeditiously view and manage large multidetector CT datasets.

Advanced Visualization: The Clinical Difference
The one-two combination of multidetector CT and advanced visualization software like GE Healthcare’s VolumeShare2 allows practices to reinvent patient care, transforming conventional invasive procedures into a simple, non-invasive means of determining appropriate clinical treatment.

Take for example vascular occlusive disease evaluation. A vascular specialist can suspect or predict peripheral vascular occlusive disease with a thorough history and physical examination, but usually cannot determine the exact location or severity of the blockage. Without this information, the clinician can not make a definitive decision about appropriate treatment. The next step usually is a duplex ultrasound with pulse volume recordings to confirm the clinical diagnosis of a hemodynamically significant blockage and approximate location. It does not, however, provide data about the exact location, length or severity of the blockage or offer information about other vascular problems.

The traditional approach was to proceed to an invasive angiogram, an expensive all day hospital visit. Conventional angiography for purely diagnostic purposes is far from ideal or preferred, says Barry Stein, MD, FSIR, interventional radiologist and director of the division of cardiovascular MRI & CT and advanced imaging analysis & 3D laboratory at Hartford Hospital and Jefferson Radiology in Hartford, Conn. “CT angiography enhances the new paradigm of non invasive vascular diagnosis allowing accurate therapeutic planning of patient care without the need for an invasive diagnostic angiogram. Now, the patient can undergo a quick diagnostic CTA and with VolumeShare2 and VesselIQ Xpress, we can procure an accurate vascular map to interrogate all major blood territories. The endovascular specialist then is able to efficiently and accurately plan appropriate therapy and triage the patient into the appropriate arm of clinical management. Many patients with occlusive disease are excellent candidates for endovascular management such as angioplasty and stent placement while others should rather undergo open surgical procedures. The exquisite 3D anatomical images provide an added benefit allowing me to demonstrate to the patient in clear and very personal terms their anatomy and pathology during our office consultation prior to any intervention and procedure.”

CT angiography changes the clinical processes. The 3D images created with VolumeShare2 and VesselIQ Express are used to guide treatment and accompany the patient during the interventional procedure or surgery. “The ability to view complex vascular anatomy in a 3D format has become an indispensable tool for interventionalists and surgeons,” Stein says.