A Vision Realized

Kathryn J. McCullough|2018-11-21

While imaging professionals work to contend with the progression of disease, they strive to improve diagnostic accuracy that supports personalized treatment for each patient, all while maintaining operational efficiency.

Photos: Peter J. Reese & Alex Teuscher

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The challenge is clear: medical imaging must keep pace with progressive disease. Medical imaging noninvasively visualizes the physiology of disease and provides clinicians vital information that aids them in developing and monitoring a patient’s treatment strategy. Yet, the fact remains that progressive disease often outpaces medical imaging. “One of the problems with imaging is that you’re always running behind. The tumor has either grown or metastasized even in a very early stage of the disease, and it’s difficult to detect those very small locations of metastases,” emphasizes Dr. Walter Noordzij, PhD, MD, nuclear physician at the University Medical Center Groningen (UMCG) in the Netherlands.

Addressing a medical need of such magnitude proves daunting, especially when the pressure to support precision medicine and maximize operational efficiency compounds the challenge. For medical professionals, utilizing the latest innovations in imaging technology is a step towards overcoming this complex challenge. For Prof. Niklaus Schaefer, MD, nuclear physician at Centre Hospitalier Universitaire Vaudois (CHUV) in Lausanne, Switzerland, the approach is clear. “On one side we really want to propagate nuclear medicine as the best possible tool to visualize complex diseases, for example to better plan a treatment or assess response. For this we need the best possible scanner and for me, nuclear medicine is really facilitating precision medicine now.”

Dr. Mario Jreige and Martin Pappon walk the halls of CHUV.
Dr. Mario Jreige and Martin Pappon walk the halls of CHUV as they discuss the day‘s patient scans.

In medical imaging, precision medicine translates to the precise visualization of disease. Such precise visualization provides physicians detailed diagnostic information that may influence the treatment path for a patient.
For Dr. Mario Jreige, MD, a radiologist and nuclear medicine resident at CHUV, “it’s very important to provide patients with the best treatment and technologies that we have. And now that we have Biograph Vision™, we are working to adapt our knowledge and capacities to provide better healthcare, diagnostic capacities, and treatment to our patients.”

Technology that enables physicians to visualize disease in a way that facilitates better treatment is the fundamental cornerstone of nuclear medicine. For a field that was notoriously dubbed as “unclear medicine” in the past, the ability to deliver precise imaging changes how clinicians perceive disease. Schaefer elaborates, “over the years, nuclear medicine went from something that was seen as not very clear to really a precise form of medicine. Nuclear medicine is changing clinicians’ perceptions because we can now see nodules that are three millimeters, and it’s augmenting our perception of disease.”

Dr. Walter Noordzij, PhD, MD, University Medical Center Groningen

As a physician, having access to PET/CT technology that acquires images which challenge previous perceptions of nuclear medicine—the possibilities as well as the limitations—incites excitement. Noordzij recounts his enthusiasm upon seeing the precise detail of Biograph Vision’s images. “When we got the image of the first patient, we were very excited. We could see lesions that were clearly outlined and also seemed fairly homogeneous, not patchy because of the different noise levels. It was a completely different kind of image.”

Martin Pappon and Dr. Silvano Gnesin examine Biograph Vision images at CHUV.
Martin Pappon and Dr. Silvano Gnesin discuss recently acquired images on CHUV‘s Biograph Vision.

Admittedly, the science of PET/CT is impressive and complex: in one machine resides technology that combines physics, biology, medicine, engineering, and an abundance of innovation.

Examining recent PET/CT images acquired on Biograph Vision, Dr. Silvano Gnesin, PhD, medical physicist at CHUV, reflects on how the system’s advanced technology enables such precision. “We would traditionally reconstruct the field of view with about 250 x 250 voxels discretization in each direction, and we had voxels of around two and a half millimeters. Now we can go down to half of this size.”

Expounding on how Biograph Vision’s core technology can advance precise PET/CT imaging, Prof. Ronald Boellaard, PhD, medical physicist at UMCG, offers his insights. “The high resolution makes images with more spatial detail which also means the signal, such as for a small tumor or lymph node, will be less spread. By making a PET system with smaller detectors, you improve the spatial resolution and also reduce the partial volume effect, which leads to sharper images and more accurate quantification.”

Dr. Walter Noordzij examines Biograph Vision’s image quality at UMCG.
Dr. Walter Noordzij and team member examine Biograph Vision’s image quality at UMCG.

While there is much excitement over the technological advancements of Biograph Vision and the resulting image quality, it is important to remember the technology’s ultimate purpose: visualizing disease in such a way that helps physicians determine the best path of patient care. As the first two sites with the latest PET/CT technology, UMCG and CHUV are just beginning to discover Biograph Vision’s potential.

At UCMG, Prof. Ronald Borra, PhD, MD, explains, “Biograph Vision is extremely sensitive with a high resolution. We can see exactly where the tracer binds to the tumor and we see the volume and distribution much more accurately. All of those things can play a key role in steering the patient’s therapy toward the best possible clinical outcome.”

Prof. Ronald Borra, PhD, MD, University Medical Center Groningen

Physicians at CHUV also see the capacity for this new technology to aid in the determination of a patient’s therapy plan. Schaefer explains, “for those patients where localized treatment plays a huge role—in prostate cancer or lung cancer—it is certainly a factor because we need the fastest and highest form of resolution. In those situations, Biograph Vision will play a big part.”

Martin Pappon prepares a patient for a scan on CHUV’s Biograph Vision.
Technologist Martin Pappon positions a patient for a scan on CHUV‘s Biograph Vision.

While the connection between advancements in imaging technology and the impact on patient care may be apparent, another vital part of the challenge is how to handle daily operational demands efficiently.

Equipped with the latest advancement in PET/CT technology, UMCG and CHUV are able to discover what it means to be precise and operationally efficient, simultaneously.

At CHUV, Prof. John Prior, PhD, MD, FEBNM, head of nuclear medicine, elaborates that Biograph Vision enables his team to acquire scans, “probably 30% faster with about 30% less dose, which is something extraordinary.”

However, for the team at UMCG, the realization that Biograph Vision allows them to couple precision and operational efficiency came quite unexpectedly. According to Borra, “one of the things we wanted to do was push the scanner to the limits and at some point, without meaning to, we entered seven seconds per bed. So, in total, we had around a 50-second scan for seven bed positions. We all expected the quality to be very poor, but the resulting images turned out to have spectacular quality for such a short scan time. One of my nuclear research colleagues said, ‘This thing is amazing. We can do so many scans.’ It was not something we intended, but it was a very early sign of how extremely good Biograph Vision is.”

Prof. Niklaus Schaefer, MD, Centre Hospitalier Universitaire Vaudois
Dr. Mario Jreige and Martin Pappon study Biograph Vision’s images.
Dr. Mario Jreige and Martin Pappon study Biograph Vision‘s next-generation imaging capabilities.

Technologies such as Biograph Vision are just one step in the advancement of medicine as it looks to keep pace with the progression of disease.
For Schaefer, while he recognizes the opportunities advanced PET/CT technology present, he also emphasizes that the responsibility of true progress resides with the physicians. “We have to understand what our high-resolution images mean. What is real disease? Does it play a role? I think having a great tool certainly allows for the best possible way to measure disease, but it has to be followed by some kind of decision from a clinician. To understand its real value and its impact on management, we need clinical trials together with our clinical partners.”

Jreige stresses, “it is important for us to progress; not to remain where we are, and not just do a routine clinical workup. It‘s crucial for patients to receive their staging, monitoring, and therapy, but it’s also important for us to better understand cancer and other pathologies, as well as the continuum and difference between these entities so we can make diagnoses with more ease. It‘s important for us to understand the physiology of the disease, and having new technologies that help us do this is very promising and satisfying.”

Kathryn J. McCullough is a writer and editor for Siemens Healthineers based in Knoxville, Tennessee, USA.