Clinical Application to Improve the “Depth Perception Problem” by Combining Augmented Reality and a 3D Printing Model

Abstract

Background: In our experience with intraoperative evaluation and educational application of augmented reality technology, an illusion of depth has been a major problem. To improve this depth perception problem, we conducted two experiments combining various three-dimensional models and holograms and the observation angles using an augmented reality device. Methods: In experiment 1, when observing holograms projected on the surface layer of the model (bone model) or holograms projected on a layer deeper than the model (body surface model), the observer's first impression regarding which model made it easier to understand positional relationships was investigated. In experiment 2, to achieve a more quantitative evaluation, the observer was asked to measure the distance between two specific points on the surface and deep layers from two angles in each of the above combinations. Statistical analysis was performed on the measurement error for this distance. Results:In experiment 1, the three-dimensional positional relationships were easier to understand in the bone than in the body surface model. In experiment 2, there was not much difference in the measurement error under either condition, which was not large enough to cause a misunderstanding of the depth relationship between the surface and deep layers. Conclusions: Any combination can be used for preoperative examinations and anatomical study purposes. In particular, projecting holograms on a deep model or observing positional relationships from not only the operator's viewpoint, but also multiple other angles is more desirable because it reduces confusion caused by the depth perception problem and improves understanding of anatomy.

Synthetic Degradable Polyvinyl Alcohol Polymer and Its Blends with Starch and Cellulose—A Comprehensive Overview

“…In terms of structure, cellulose is a linear polymer made up of glucose, and the glucose units are connected by β(1→4) glycosidic connections, which enable the cellulose chains to form strong interchain hydrogen bonds [6,61]. Even though cellulose has a number of benefits, including a high thermal resistance, UV barrier capacity, and FDA-acquired GRAS status, its hydrophilic nature, poor vaporized water barrier properties, and limited longterm stability, along with its poor mechanical properties due to its sensitivity to moisture, limit its use in food packaging at the industrial level [62].…”

“…Due to its flexibility, toughness, and water resistance, cellulose derivatives such as cellulose acetate, carboxymethylcellulose, and hydroxymethylcellulose are regarded as significant sources of biomaterial-based food packaging. However, they are costly when used in large quantities [61]. By being transformed into nanocrystals, cellulose can potentially be used as a reinforcement in nanocomposite films [61], microfibrils [66], and nanofibrils [67].…”

“…However, they are costly when used in large quantities [61]. By being transformed into nanocrystals, cellulose can potentially be used as a reinforcement in nanocomposite films [61], microfibrils [66], and nanofibrils [67]. Cellulose reinforcements have superior mechanical qualities that are on par with those of glass and carbon nanofibers.…”