Pmod image analysis software version 3

Information on data preprocessing and the quantification of the NET is described in detail elsewhere [8 (link)]. In short, individual time frames of the dynamic PET scan were readjusted to the mean of frames with no head motion, determined by visual inspection. The readjusted images were then coregistered to each subjects MRI scan using a mutual information algorithm in SPM8 (Wellcome Trust Centre for Neuroimaging, London, UK: http://www.fil.ion.ucl.ac.uk/spm/). The caudate is considered devoid of NET [20 (link)] and was therefore used as the reference region for the parametric images of NET BP_ND. The caudate was manually delineated on individual MRIs using PMOD image analysis software, version 3.1 (PMOD Technologies Ltd, Zurich, Switzerland, www.pmod.com). NET quantification was calculated according to Arakawa et al. [21 (link)]. BP_ND was calculated as the ratio between the area under the time-activity curve of the target region and the area under the time-activity curve for the reference region minus 1. An integration interval of 120–180 min was applied. The caudate was manually delineated on individual MRIs using PMOD image analysis software, version 3.1 (PMOD Technologies Ltd, Zurich, Switzerland, www.pmod.com). The developed transformation matrices were applied to the coregistered parametric images and then warped into MNI standard space.

All image data were processed and analyzed using PMOD image analysis software version 3.7 (PMOD Technologies Ltd, Zurich, Switzerland). Dynamic PET data were motion-corrected to a late time point image [40–45 min post-injection (p.i.)] of the scan. An average PET image of 20–60 min p.i. of the motion-corrected time series was calculated for each subject. Based on this, the dynamic PET scan was registered and matched to the individuals’ MP-RAGE image volume. Furthermore, four static PET images of 30 min scan time were created for each patient by averaging over six consecutive of these preprocessed frames starting at 30, 40, 50 and 60 min.

MIBG uptake was semi-quantitatively evaluated on the planar anterior images by calculating the H/M ratio using the PMOD image analysis software version 3.7 (PMOD Technologies Ltd, Zurich, Switzerland). First, ME images were automatically co-registered to the LE images and fused. Then, two investigators (JB; CL) defined ROIs of the heart and the mediastinum independently from each other on the fused image data. The center of a circle and one rectangular ROI was manually placed on the heart and the upper mediastinum, respectively. The ROIs were then transferred to the co-registered LE and ME image data and H/M ratios were calculated. Finally, the mean H/M ratio of both raters was calculated for each collimator and each patient by dividing the mean counts per pixel in the cardiac ROI by the mean counts per pixel in the mediastinal ROI.