THE EFFECT OF TEMPLATES ON 99MTC-ECD SPECT HEALTHY BRAIN PERFUSION ANALYSIS USING STATISTICAL PARAMETRIC MAPPING
Bang‐Hung Yang, Shyh-Jen Wang, Yuan-Hwa Chou, Tung‐Ping Su, Jyh‐Cheng Chen · Biomedical Engineering Applications Basis and Communications · 2006
Objective: In vivo stability of tracer distribution of 99mTc-ECD SPECT images for healthy individuals are important to the application of regional cerebral blood flow (rCBF) in neurological studies. Statistical parametric mapping (SPM) software has been designed for voxel-by-voxel analysis of the whole brain imaging. Spatial normalization is the essential preprocessing step to transform individual images into the MNI standard template which corresponds with Talairach anatomic coordinates. However, the SPECT standard template provided with SPM2 software is 99mTc-HMPAO brain perfusion image. The purpose of this study was to evaluate the outcome of templates on 99mTc-ECD test-retest study of healthy brain perfusion analysis. Material and Methods: Fifteen healthy volunteers were included in this study. SPECT images were acquired at 30 minutes after injection of 740 MBq of 99mTc-ECD. We utilized three kinds of spatial normalization templates to assess the outcome of 99mTc-ECD test-retest study: (1) the standard SPM2 SPECT template; (2) an 99mTc-ECD template; and (3) an MRI-based normalization template. Statistical model of paired t-test was applied and the changes of rCBF were significant if corrected p value was less than 0.05. Results: Test-retest of 99mTc-ECD images showed no changes of rCBF in each template. However, we found there are slight differences among the different normalization templates. Conclusion: Investigations of rCBF under varying input conditions, such as physiological state, could be neglected. Thus, we have good reproducibility of 99mTc-ECD images. In addition, using anatomical normalization, which requires MRI data from individual subject, may be the best spatial transformation approach.