Abstract

A fully automatic framework is proposed to identify consis- tent landmarks and wire structures in a rotational X-ray scan. In our application, we localize the balloon marker pair and the guidewire in between the marker pair on each pro jection angle from a rotational fluoroscopic sequence. We present an effective o?ine balloon marker tracking algorithm that leverages learning based detectors and employs the Viterbi algorithm to track the balloon markers in a globally opti- mal manner. Localizing the guidewire in between the tracked markers is formulated as tracking the middle control point of the spline fitting the guidewire. The experimental studies demonstrate that our methods achieve a marker tracking accuracy of 96.33% and a mean guidewire lo- calization error of 0.46 mm, suggesting a great potential of our methods for clinical applications. The proposed o?ine marker tracking method is also successfully applied to the problem of automatic self-initialization of generic online marker trackers for 2D live fluoroscopy stream, demon- strating a success rate of 95.9% on 318 sequences. Its potential applica- tions also include localization of landmarks in a generic rotational scan.