Assessing the 3D accuracy of consumer grade distance camera measurement of respiratory motion

• Published in: Journal of physics. Conference series 2017-05, Vol.851 (1), p.12030
• Main Authors: Samir, M, Golkar, E, Rahni, A A Abd
• Format: Article
• Language: English
• Subjects: Accuracy; Cameras; Distance measurement; Medical imaging; Physics; Quality; Radiation therapy
• ISSN: 1742-6588; 1742-6596
• DOI: 10.1088/1742-6596/851/1/012030

Recently range imagers or distance camera systems have garnered interest for measuring respiratory motion without using markers, which can then be used as a surrogate in diagnosis and treatment for example in diagnostic imaging or radiotherapy. However, their use may have limitations, especially among lower cost systems, whereby their accuracy decrease greatly with the distance of the patient from the camera. This is considering the fact that the motion amplitude of the anterior surface of the body in normal breathing is typically around 1 cm or less, which is at the limit of accuracy of these systems. This accuracy limitation is even more pertinent when the fact that the 1 cm accuracy is desired over the whole anterior surface that is image and not just an average measurement of distance. We study this limitation in a low cost system i.e. the Microsoft KinectTM, using both version 1 and version 2 of the sensor. The 3D accuracy of both versions is compared with an alternative method of respiratory motion measurement i.e. a respiratory belt, at a distance of around 1.35 m. This study can be a guide for the design and application of range imaging systems in the clinical setting.