Jan 31, 2023

Three Class III Obese ViP Models for Improved Patient Coverage

At the request of the magnetic resonance (MR) industry, the IT’IS Foundation has created three new class III obese* Virtual Population (VIP) models. With a body mass index (BMI) of more than 60 kg/m2, these new computational phantoms are the first to represent the upper end of the population.

The models were created by morphing existing image-based ViP models Ella V3.1 (BMI 63) and Fats V3.2 (BMI 66 and 70 respectively) to reach a target BMI, increasing the amount of fat and muscle via a biomechanics-based morphing approach. By treating the bones as hard tissues and enforcing biomechanical deformation of the soft tissue, the morphing is constrained within a realistic regime: bones do not change, and organs within the rib cage are minimally affected. Two models target primarily fat (adipose) addition, while the highest BMI model targets the addition of both muscle and fat.

The models meet the stringent ViP quality standards and include all tissues segmented in ViP V3.x models. They have been reviewed by external reviewers from the Anatomy Department of the University of Zurich. All models are posable using the Sim4Life poser tool – in fact, as the animation shows, they are surprisingly flexible!

The release is an important extension of our existing ViP that aims for a better representation of the patient population, which supports the development of ultra-wide-bore MRI scanners and safety evaluations that are relevant for an underrepresented patient population with class III obesity.

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* class III obesity (formerly known as morbid obesity) corresponds to BMI > 40kg/m2