High-accuracy and real-time 3D positioning, tracking system for medical imaging applications based on 3D digital image correlation

• Traditional coarse search of DIC method was improved 4–10 times.
• The system realized real-time tracking for faster motion of discontinuous markers. An object can be tracked with 6 degrees of freedom through markers.
• Experiments about surgical navigation and muscular movement were presented.

This paper presents a system for positioning markers and tracking the pose of a rigid object with 6 degrees of freedom in real-time using 3D digital image correlation, with two examples for medical imaging applications. Traditional DIC method was improved to meet the requirements of the real-time by simplifying the computations of integral pixel search. Experiments were carried out and the results indicated that the new method improved the computational efficiency by about 4–10 times in comparison with the traditional DIC method. The system was aimed for orthognathic surgery navigation in order to track the maxilla segment after LeFort I osteotomy. Experiments showed noise for the static point was at the level of 10−3 mm and the measurement accuracy was 0.009 mm. The system was demonstrated on skin surface shape evaluation of a hand for finger stretching exercises, which indicated a great potential on tracking muscle and skin movements.