A real‐time respiratory motion monitoring system using <scp>KINECT</scp>: Proof of concept

TLDR

The study investigates the feasibility of a low‑cost respiratory motion monitoring system using the Microsoft KINECT sensor. The authors enhanced KINECT’s depth resolution to 1 mm with motion magnification, captured 30 Hz depth traces over a thoracic ROI, and compared them with a commercial strain‑gauge system in four volunteers. The KINECT traces correlated strongly with strain‑gauge data (mean CC = 0.969), demonstrating feasibility and offering an economical alternative for respiratory motion monitoring.

Abstract

Purpose: The purpose of this study is to investigate the feasibility of a low‐cost respiratory motion monitoring system based on the Microsoft KINECT sensor. Methods: The authors increased KINECT 's inherent depth resolution from 1 cm to 1 mm via a motion magnification system. Using the KINECT software development kit, the authors programmed the KINECT to capture depth images and determine the average depth over a thoracic region of interest, viewed almost parallel to the subject's surface. KINECT respiratory traces (average depth vs time at a rate of 30 Hz) were acquired from four volunteers and compared with those simultaneously acquired using a commercially available strain gauge respiratory gating system. Results: The correlation coefficient (CC) between KINECT and strain gauge traces varied from 0.958 to 0.978, with a mean CC of 0.969. This strong correlation was also demonstrated by the joint probability distribution and visual inspection. Conclusions: It is feasible to use the KINECT for respiratory motion tracking. Traces are similar to those of a clinically used strain gauge system. The KINECT ‐based system provides a new and economical way to monitor respiratory motion.