RT Journal Article SR Electronic T1 Investigation of helical CT with rigid body translation for attenuation correction of cardiac PET data JF Journal of Nuclear Medicine JO J Nucl Med FD Society of Nuclear Medicine SP 390P OP 390P VO 49 IS supplement 1 A1 Tinsu Pan A1 Lance Gould A1 Osama Mawlawi A1 Martha Mar A1 Eric Rohren A1 Homer Macapinlac YR 2008 UL http://jnm.snmjournals.org/content/49/supplement_1/390P.1.abstract AB 1643 Objectives: To investigate the application of helical CT with rigid body translation (RBT) for attenuation correction (AC) of cardiac PET data. Methods: Four patients were scanned with PET/CT and cine CT at the same imaging session on a GE Discovery ST PET/CT scanner. There was no known myocardium infarction or ischemia for the patients. There was misregistration of the heart between helical CT (HCT) and PET data in each patient. Average CT (ACT) from cine CT was able to correct for the false-positive deficit in the anterior (A) and anterior lateral (AL) walls most susceptible to the misalignment between the HCT data at end-inspiration and the PET data of average respiration. We designed software to overlay the HCT and PET images and applied RBT on HCT to cover the A and AL walls in PET data, and applied the HCT- RBT for AC of the PET data. The PET data corrected by ACT, HCT and HCT-RBT were quantitatively analyzed with quantitative perfusion software (QPS) of Hermes Medical Solutions. Results: Relative to ACT data, the maximum deficits with HCT in the A wall over three segments for the four patients were -16, -15, -17 and -29% and with the HCT-RBT were -7, 5, -18 and -4%. The deficits were -17, -17, -25 and -33% with HCT in the AL wall became -3, 3, -10 and -1% with HCT-RBT. There was improvement in reducing deficits in both walls with HCT-RBT over HCT. However, one anterior septal wall of one patient changed from 25% to -22% indicating a potential shift of deficit with HCT-RBT. Conclusions: RBT can improve the PET data of anterior and anterior lateral walls. However, some other area may be compromised by RBT.