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Abstract #3430

Combining Active Markers and Optical Tracking for Prospective Head Motion Correction

Murat Aksoy1, Melvyn Ooi1, Ronald D. Watkins, Daniel Kopeinigg, Christoph Forman2, Roland Bammer1

1Center for Quantitative Neuroimaging, Department of Radiology, Stanford University, Stanford, CA, United States; 2Computer Science, Friedrich-Alexander-University Erlangen-Nuremberg, Erlangen, Germany

Active markers and optical tracking systems (i.e. cameras) have been used for prospective correction of motion artifacts in head MRI. Optical tracking systems have the advantage that they require no additional MR data acquisition (i.e. navigators) to detect motion, whereas active markers can detect motion without the need to perform cross-calibration between the scanner and the tracking system. In this study, we combined active marker and optical tracking to benefit from the advantages of both systems. The active marker system was used to perform cross-calibration of the optical tracking system in a very short time with no discomfort to the patient so that the actual tracking can be done with the camera.

Keywords

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