Automatic Calculation Of Lateral Diameter For Size-Specific Dose Estimate Using A Matlab-Based Kinect Camera

Abstract

In this paper, we develop a Matlab-based program on a Kinect camera to automatically calculate lateral diameter (D lat ) for estimating size-specific dose estimate (SSDE). SSDE is a metric used to express the patient’s dose in a CT examination. This metric depends on two other parameters, namely the volume computed tomography dose index (CTDI vol ) and specific parameters of the patient's body size, especially the effective diameter (D eff ). CTDIvol can be accessed from the control panel at the time of the CT examination, while D eff can be estimated using D lat . A segmentation technique applied to the depth image was used to obtain D lat from the binary image of the participants with a total of 61 individuals with an average age of 22 years. Data analysis showed that D lat measurements using the Kinect camera and a ruler had a mean absolute difference of 6.10% with R 2 of 0.76. Meanwhile, D eff estimated from both D lat measurements showed a mean absolute difference of 7.11% with R 2 of 0.75. The Kinect camera was able to calculate the participants' D lat and D eff quite well from binary images using segmentation techniques to replace manual and patient’s axial image calculation. The advantages of this method are no radiation, insignificant background noise, efficient measurement, and high portability.