WE‐G‐BRC‐02: A Portable Optical CT Scanner for Interactive Teaching of Imaging Principles

Abstract

Purpose: To develop a portable scanner that demonstrates the principles of radiography and computed tomography (CT). Methods: The traditional methods for teaching the physics of medical imaging rely on lectures, followed by demonstrations on a clinical system that is not easily accessible or programmed for educational purposes. We have developed a scaled‐down portable CT imaging system suitable for interactive “real time” demonstrations using a laptop computer during a classroom or lab session. Our optical system uses light rays in lieu of x‐rays so that experiments can be conducted while posing no electrical or radiation hazards to instructors and students. The desk‐top CT imaging device will be supplied with a learning kit of experimental test phantoms, lab manuals, instructional videos, and specialized software that demonstrate 2D radiographic and 3D CT image reconstruction methods. These approaches are relevant to imaging systems used in digital diagnostic imaging and image‐guided therapy. Results: A low‐cost portable system (< $15,000) has been manufactured (http://www.deskcat.com/) to enrich the studentˈs learning experience and improve the retention of fundamental imaging concepts. Students learn about spatial resolution, contrast resolution, system linearity, image artifacts and they perform quantitative measurements in 3D space, using image visualization software tools and specialized test phantoms (7.2 cm diameter × 5.3 cm long). Early reaction from instructors and students alike has been very encouraging. Conclusions: This learning package should prove attractive to universities with medical physics programs in Departments of Physics, Medical Biophysics, or Biomedical Engineering, as well as Medical Schools with residency training programs (Medical Imaging, Radiation Oncology). The systemˈs modular nature allows extensions for future coverage of related topics such as nuclear and molecular SPECT imaging. Through future developments, it may also be possible to model the dose deposition patterns from intensity‐modulated radiotherapy beams using ultraviolet exposure of radiochromic gel volumes. This research was sponsored by the Ministry of Research and Innovation, Government of Ontario, Canada (ORDCF Grant, OCITS Project) and by Modus Medical Devices as the industry partner. We also thank The University of Western Ontario for providing funding through its “Fellowship for Teaching Innovation”. This supported one of the authors (RT) during a summer studentship.

A simple and low cost USB webcam-driven optical tomography system suitable for teaching x-ray computed tomography

“…36 projections were manually acquired in a 360 degree scan. Battista et al [27] presented a portable commercial experimental kit at a cost of less than 15 kU$, which is currently marketed [28]. The system seems to be the first to be presented with a diffuse light source.…”

“…Also, SPECT could be demonstrated by injecting a chemiluminescent dye in a phantom cavity and taking two tomography scans: one with the red color source switched on and another with all the light source switched off. As already mentioned, Battista et al [27], Orfanakis [30] and De Deene [17] used a diffuse light source. Diffuse light sources are useful to minimize image shadows.…”