[Availability of normal database by single photon emission computed tomography system with use of 3 dimensional-stereotactic surface projections].

PURPOSE

The present study aims to quantitatively investigate a normal database (NDB) created under the same acquisition and reconstruction conditions for three gamma camera systems (four types of collimator systems) with use of three-dimensional stereotactic surface projections (3D-SSP). We rebuilt a NDB with use of the N-isopropyl-p-(123)I-iodoamphetamine ((123)I-IMP) SPECT data derived from 30 healthy individuals at 20 institutions nationwide. We standardized the acquisition and reconstruction conditions, evaluated Z scores using patient data (PD) and examined each compensation effect.

RESULTS

Z scores determined using the advanced NDB were the same value. Artifacts were often generated in Z score maps derived from the conventional NDB (CONDB). The Z score of the own site NDB (OWNDB) was 70% of that calculated based on the CONDB. The combinatorial difference in compensation (scatter and attenuation) resulted in many artifacts being generated in Z score map images.

DISCUSSIONS

More artifacts were generated in Z score map images using the novel NDB compared with the CONDB. The novel NDB was comparable to the performance of OWNB. The accuracy of brain function image analysis can be improved the reconstruction conditions and correcting for scatter and attenuation on both the novel NDB and PD.