Respiratory signal generation for retrospective gating of cone-beam CT images

Stefan Wiesner; Ziv Yaniv

doi:10.1117/12.768849

Abstract

We are currently investigating the acquisition of 4D cone-beam CT data using retrospective gating of the X-ray projection images. This approach requires a respiratory signal that is synchronized with image acquisition. To obtain such a signal we propose to use a spherical fiducial attached to the patient's skin surface such that it is visible in the images. A region of interest containing the fiducial is manually identified in an initial image and is then automatically detected in all other images. Subsequently, we perform an approximate spatial (3D) reconstruction of the marker location from its 2D locations. Finally, we compute a respiratory signal by projecting the 3D points onto the major axis estimated via principle component analysis. As this respiratory signal was obtained from the fiducial location in each of the images it is implicitly synchronized with image acquisition. We evaluate the robustness of our fiducial detection using an anthropomorphic respiratory phantom. To evaluate the quality of the estimated respiratory signal we use a motion platform that follows the respiratory motion obtained by tracking the skin surface of a volunteer. We show that our method generates a respiratory signal that is in phase with the ground truth signal, but suffers from inaccuracies in amplitude close to the anterior-posterior imaging setup where the primary direction of motion is perpendicular to the image plane. Thus, our method should only be used for phase based retrospective gating.

Citation Download Citation

Stefan Wiesner, Ziv Yaniv, "Respiratory signal generation for retrospective gating of cone-beam CT images", Proc. SPIE 6918, Medical Imaging 2008: Visualization, Image-Guided Procedures, and Modeling, 691817 (17 March 2008); doi: 10.1117/12.768849; https://doi.org/10.1117/12.768849

ACCESS THE FULL ARTICLE

PERSONAL SIGN IN
Full access may be available with your subscription

Email or Username Forgot your username?

Password Forgot your password?

Show

Remember Email/Username on this computer

Remember Password

No SPIE account? Create an account
or Institutional Sign In via Shibboleth

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available

Members: $14.40

Non-members: $18.00 ADD TO CART

Show All Keywords

Keywords/Phrases

Search In:

Publication Years