Developments in Weight Bearing Computed Tomography

, Francois Lintz², Cesar de Cesar Netto³, Alexej Barg⁴, Arne Burssens⁵ and Scott Ellis⁶

(1)

Department for Foot and Ankle Surgery, Hospital Rummelsberg, Schwarzenbruck, Germany

(2)

Foot and Ankle Surgery Centre, Clinique de l’Union, Toulouse, France

(3)

Department of Orthopedics and Rehab, University of Iowa, Iowa City, IA, USA

(4)

University Orthopedic Center, University of Utah, Salt Lake City, UT, USA

(5)

Department of Orthopedics and Trauma, University Hospital of Ghent, Ghent, OVL, Belgium

(6)

Department of Orthopedic Surgery, Hospital for Special Surgery, New York, NY, USA

Keywords

Weight-bearing computed tomography (WBCT)Dynamic measurementPressure sensor integrationHolographic 3D visualization

What is the future of WBCT in the foot and ankle? What are the needs and what is feasible? Regarding the WBCT scan, faster scanning times, lower radiation dose, larger scan volume, and better image quality will be the next reachable developments. More challenging will be dynamic scans, i.e., scanning the foot and ankle during the entire gait stance phase. Even though the actual standard imaging is also static, dynamic imaging would be desirable, for example, dynamic pedography or gait motion analysis [1]. Much faster scanning times like 20 scans per second and a very large scanning volume will be needed to allow for dynamic scan of the foot and ankle during the entire stance phase. An inclusion of dynamic pressure and force measurement will be an easy adjunct, as these methods do already exist (section “Angle Measurement: Differences Between Methods” and “Angle Measurement: Intra- and Interobserver Reliability”) [2–4]. However, dynamic scanning and addition of other data (e.g., pedographic data) acquisition modalities will register excessively more data than to date. This calls into question how these data are stored, visualized, analyzed, and interpreted. The use of conventional two-dimensional monitors will not allow for adequate visualization of three-dimensional and maybe even dynamic instances. Holographic visualization could be helpful but could not be adequately developed so far (Fig. 23.1) [5]. This will require heavy investments from the industry. It requires even faster data transfer speeds and projection technology, including advanced interfacing, enabling surgeons to interact manually with the models, which to date is only in the development phase and far from being available in the daily clinical setting. However, surgeons have been inventive and are for now using existing technology such as third-party software, holographic lenses, or 3D printing solutions for better visualization. In any case, WBCT developers are making tremendous ongoing progress with their onboard software solutions to make datasets readily available and easy to navigate right on the spot of patient scanning. The next issue is data analysis. Automatic measurements are already possible (section “Shortcomings of the Study”) and will be included in all software solutions in the near future. Further data analysis, for example, diagnosis of foot deformities, will require artificial intelligence (AI) for automatic analysis of extensive data volumes. Enormous databases will be needed to build up a sufficient AI. New three-dimensional measurement modalities in addition to angles and distances between bones need to be defined; standard values will have to be assigned and guidelines adapted or created. At least a whole generation of foot and ankle surgeons will have to find all the solutions, and we are just at the start of this exciting process. A new era of foot and ankle imaging has started, and we are facing an exciting and promising future.