WellSpan Health steps into the future with spectral CT

WellSpan Health is an eight-hospital IDN made up of 2,600 physicians and advanced practice providers and includes the region’s only accredited Level One Trauma and Stroke Center. When Edward Steiner, MD, FACR, joined WellSpan four years ago as Chairman of Imaging and Radiation Oncology, he knew the imaging equipment could not support the health system’s mission to deliver exceptional care for all.

Over a two-year period Dr. Steiner and the WellSpan team worked with many vendors to chart the best path forward, and eventually decided to collaborate with Philips to install a fleet of 12 cutting-edge spectral detector CT scanners for its imaging and radiation oncology departments.

Spectral CT uses two separate x-ray photon energy spectra to visualize tissue composition to allow for the interrogation of materials that have different attenuation properties at different energies. “Spectral CT is the way to visualize tissue composition, not only attenuation, but actual tissue composition. If we can determine the amount of iodine in tissue that’s enhancing – if we can subtract the iodine – and if we can manipulate fatty tissues, we really are ahead of the game in diagnosis,” says Dr. Steiner.

With spectral CT, conventional CT images are paired with layers of spectral results in the same scan, allowing what was once invisible or not diagnosable to now being both visible and diagnostic. These spectral layers include:

There are three ways to obtain spectral data and multiple ways to process it. According to Dr. Steiner, this means that choosing the right approach to fit your workflow and clinical needs is crucial. “My approach was very scientific,” he said. “I went to our physicists and we looked at all the vendors and at spectral separation. I looked at temporal cohesion, and then lined them up to see what each vendor had to offer in terms of hardcore physics data. Then, we looked at how the data is processed and how we were going to do it in York.”

Spectral CT can be accomplished utilizing three different methods. One is dual source DECT, where two X-ray tubes at different energy outputs with a dedicated detector and the computer overlays two images. The second method is kVp switching, in which the spectral tube is rapidly switching energy levels that are caught by a single detector. The third option is the Philips approach, where a single detector is simultaneously capturing and distinguishing high and low photon energy.

The WellSpan team chose to collaborate with Philips to standardize on spectral detector CT because the Philips spectral results are always on. There is no need to compromise or predetermine which patients would need spectral imaging for diagnosis. The team also appreciated how technician-friendly Philips spectral CT is and that it doesn’t require dedicated spectral protocols or add additional radiation doses, so there was no change to the team’s existing workflow. The detector technology allowed for true temporal cohesion and the data integrated into their radiologist workflow without causing data overload.

Computed tomography, or CT, is often the go-to imaging modality for a wide range of clinical indications. Conventional CT images are not always able to provide clinicians with the answers they need, and this can result in indeterminate findings, poor visualization of tissue and the need for repeat scans or alternative modalities such as MR.

Spectral CT helps provide additional clinical enhancement when you need to drill deeper to diagnose a patient, or if you are dealing with exam types that are typically difficult to accomplish with traditional CT, such as renal cysts.

With spectral CT you can complete full studies with under 50 cc’s of contrast for patients with renal failure, helping protect the kidneys. Combined with Philips proprietary Magic Glass, spectral CT enables instantaneous and simultaneous viewing of up to five different spectral results by opening a mini browser within the radiologists’ own ACS system. This simplifies use and interpretation of spectral results, and integrates it into established workflow without data overload and improving time to confident diagnosis.

“Renal cysts are a problem if they contain malignancy. They may be 100% curable when they are small nodules,” says Dr. Steiner. “It is an example of a case where you ask what am I missing by not using spectral CT? When you integrate [a conventional study] with Magic Glass, you have a secondary window and can see virtual non-contrast. [You] pull the contrast up and see its hypo-dense, but it’s not calcified. When you further manipulate the image with a push of the button, the mono-E shows you a beautiful enhancing nodule.”

With spectral CT you have the ability to not only bring virtual non-contrast (VNC) study to make sure there is no calcification, but also with iodine overlay or iodine density to quantify the degree of enhancement characterizing a lesion which would be highly suspect for carcinoma. Therefore there is no need for a costly MRI and delaying the diagnosis.

Spectral CT’s improved contrast provides better visualization in other difficult cases as well, including PE visualization in large BMI and hyperdynamic patients and detecting bowel ischemia and tumor vascularity. This enhanced visualization improves characterization of GI bleeds, helps facilitate better coronary studies and can eliminate the need for MR to define acute verses chronic fractures in patients with spinal trauma.

According to the Journal of the American College of Radiology (JACR), dual-energy CT may benefit patient care and decrease institutional cost by decreasing follow-up exams due to incomplete diagnosis and decreasing recommendations for follow-up MRI.¹ The ability to get the right diagnosis the first time can also facilitate faster discharges and reduce potential damages from missed-diagnosis lawsuits.

WellSpan Health is paving the way in the future of spectral CT standardization and, as Dr. Steiner says, “It’s more than just pretty images, it’s true results.” This project has helped the WellSpan Hospital system by improving contrast and reducing iodine doses for patients. It has helped decrease utilization of follow-up studies, improved triage, discharges, and patient flow and has helped improve time to diagnosis.*