Correction of head movement on PET studies: comparison of methods

TY - JOUR

T1 - Correction of head movement on PET studies

T2 - comparison of methods

AU - Montgomery, Andrew J

AU - Thielemans, Kris

AU - Mehta, Mitul A

AU - Turkheimer, Federico

AU - Mustafovic, Sanida

AU - Grasby, Paul M

PY - 2006/12/1

Y1 - 2006/12/1

N2 - Head movement presents a continuing problem in PET studies. Head restraint minimizes movement but is unreliable, resulting in the need to develop alternative strategies. These include frame-by-frame (FBF) realignment or use of motion tracking (MT) during the scan to realign PET acquisition data. Here we present a comparative analysis of these 2 methods of motion correction. Methods: Eight volunteers were examined at rest using 11C-raclopride PET with the radioligand administered as a bolus followed by constant infusion to achieve steady state. Binding potential (BP) was estimated using the ratio method during 2 periods of the scan at steady state. Head movement was compensated by using coregistration between frames (FBF) and 3 methods using MT measurements of head position acquired with a commercially available optical tracking system. Results: All methods of realignment improved test–retest reliability and noise characteristics of the raw data, with important consequences for the power to detect small changes in radiotracer binding, and the potential to reduce false-positive and false-negative results. MT methods were superior to FBF realignment using coregistration on some indices. Conclusion: Such methods have considerable potential to improve the reliability of PET data with important implications for the numbers of volunteers required to test hypotheses.

AB - Head movement presents a continuing problem in PET studies. Head restraint minimizes movement but is unreliable, resulting in the need to develop alternative strategies. These include frame-by-frame (FBF) realignment or use of motion tracking (MT) during the scan to realign PET acquisition data. Here we present a comparative analysis of these 2 methods of motion correction. Methods: Eight volunteers were examined at rest using 11C-raclopride PET with the radioligand administered as a bolus followed by constant infusion to achieve steady state. Binding potential (BP) was estimated using the ratio method during 2 periods of the scan at steady state. Head movement was compensated by using coregistration between frames (FBF) and 3 methods using MT measurements of head position acquired with a commercially available optical tracking system. Results: All methods of realignment improved test–retest reliability and noise characteristics of the raw data, with important consequences for the power to detect small changes in radiotracer binding, and the potential to reduce false-positive and false-negative results. MT methods were superior to FBF realignment using coregistration on some indices. Conclusion: Such methods have considerable potential to improve the reliability of PET data with important implications for the numbers of volunteers required to test hypotheses.

M3 - Article

C2 - 17138736

SN - 0161-5505

VL - 47

SP - 1936

EP - 1944

JO - Journal of Nuclear Medicine

JF - Journal of Nuclear Medicine

IS - 12

M1 - N/A

ER -