Jeffrey M. Bundy

The impact of two-meter total body PET versus ‘eyes to thighs’

June 17, 2022
By Jeffrey M. Bundy

When we consider what technological advances truly have the ability to bring change to patient management and outcomes, one at the forefront of molecular imaging is 2-meter total body PET. However, before we talk about how it can shape patient care in the next decade, we have to clarify what it means and how it differs from technology that has come before.

True total body PET refers to the ability to see, in one bed position, a full two meters of the human body, typically from the top of the patient’s head to their toes, in one complete image without stitching. Other technologies, such as those with fields of view near or below one meter generate “eyes to thighs” data sets or whole-body images by stitching images together in post-processing, which has limitations. First, the process of acquiring the images takes longer for the patient (which then requires more radiotracer dose as well, due to lower sensitivity). Second, separate images being connected does not allow for dynamic imaging throughout the whole body — it’s akin to showing a series of characters play their parts in a movie without seeing how all of them interact.

A full 99% of the world’s population is within 2 meters in height, which means that the impact of 2-meter PET is significant. So, what value can true total body PET add to patient care in the next decade? We see three areas with the highest clinical impact:

(1) Faster, more successful scans. At its most basic, total body 2-meter scanning means that scanning time is reduced drastically. The image the physician needs can now be acquired in as little as 60 to 240 seconds, which is full minutes less than with other technology. This means that people who have trouble lying still, following instructions, or tolerating longer exams can have successful scans more often. This may benefit more geriatric and pediatric populations, for example, with the additional benefit of a lower radiation dose as well.

(2) Smarter AI. Much has been made in recent years of artificial intelligence and its potential for improving the imaging experience, but its fundamental power lies in the underlying data. All AI relies on good training data sets. The more complete the data set, the better the intelligence developed as a result. A full two-meter total body data set is by definition more complete than what has existed with one-meter (or less), so artificial intelligence that relies on it becomes more powerful.

(3) Precision medicine. Perhaps the most far-reaching impact of true total body PET will be its impact on personalized radiopharmaceutical therapy, the idea that truly personalized medical treatment requires an understanding of how each person’s unique physiology responds to nuclear medicine. In other words, like fingerprints, a human’s physiology is very individual. Today, it is only through 2-meter total body PET that we can see the interactions of all tissues and organs throughout a person’s body in one complete dynamic exam. That helps change what the physician can visualize — it changes the pharmakinetic modeling — and opens up the potential to literally transform treatment plans.

PET has long been considered one of the most sensitive methods to see what is happening inside the body for the purpose of cancer and other disease diagnosis and treatment. With true total body 2-meter technology now brought to bear, the ability to gain a complete picture in one image that is more than just “eyes to thighs”, with less burden on the person being examined, is nothing short of revolutionary to enabling personalized medicine and improved treatments.

About the author: Jeffrey M. Bundy, Ph.D. is the CEO of United Imaging Healthcare Solutions.