Effect of Prefiltering Cutoff Frequency and Scatter and Attenuation Corrections During Normal Database Creation for Statistical Imaging Analysis of the Brain

Abstract

When the reconstruction conditions (fc, scatter correction, and attenuation correction) at normal database creation differed from those at patient data processing, the z scores widely underestimated the analytic results because the SD varied according to the reconstruction conditions. The accuracy of brain function image analysis can be improved by considering the reconstruction conditions and correcting for scatter and attenuation on both normal databases and patient data.

Towards characterizing the regional cerebral perfusion in evaluating the severity of major depression disorder with SPECT/CT

“…To minimize the deviation errors caused by analysis software packages, 3D-SSP and eZIP image-processing programs were applied in the same CT attenuation-corrected SPECT images data of MDD patients and normal controls. According to previous studies [ 24 , 25 ], the difference between 3D-SSP and eZIP lies in smoothing process after anatomic standardization. The smoothing process by eZIP is based on an SPM algorithm and effectively enhances the signal-noise ratio of images, which might overestimate cerebral hypoperfusion [ 24 , 25 ].…”

“…According to previous studies [ 24 , 25 ], the difference between 3D-SSP and eZIP lies in smoothing process after anatomic standardization. The smoothing process by eZIP is based on an SPM algorithm and effectively enhances the signal-noise ratio of images, which might overestimate cerebral hypoperfusion [ 24 , 25 ]. So we apply corrections for multiple comparisons based on family-wise error (FEW), and P FWE-corr < 0.05 is considered statistically significant in eZIP analysis.…”

Evaluation of a novel normal database with matched SPECT systems and optimal pre-filter parameters for 3D-SSP

“…Rather than conventionally setting the cutoff frequency in a low-frequency domain, we consider that it should be within the range of 0.52-0.58 cycles/cm to enhance the accuracy of detecting perfusion defects. However, the filter parameter must be correctly set for each condition depending on the dose of the radioisotope and the applied compensation (attenuation and scatter) method [21,22]. We supposed that such optimization depends on the size of the simulated lesions.…”