Evaluation of a Multi-pinhole Collimator for Imaging Small Animals with Different Sizes

Abstract

This collimator allows flexible single pinhole and MPH SPECT imaging for rodents, achieving high resolution and detection efficiency with minimal image artifacts.

Appropriate collimators in a small animal SPECT scanner with CZT detector

“…On other scanners, %STDs in the SPECT imaging showed small values when compared with our scanners [12], as no post-filter was used for our SPECT images. Therefore, we further confirmed that SPH, MPH and PAH produced different performances although Mok et al., examined the differences in performance between SPH and MPH in other scanners [8].…”

“…On the other hand, PAH was not suitable for SPECT imaging, as it yielded SPECT images with low resolution. Although Mok et al reported that MPH was appropriate for bone scintigraphy using Tc-MDP with about 67 MBq [8], we expected that SPH would be useful with higher radioactivity because the bone scintigraphy was obtained by SPH using 99m Tc-MDP with about 100 MBq [11] and 185…”

“…In other scanners, SPH provided 0.6-1.4 mm FWHM with NaI detector [12][13][14][15] [6,8]. PAH yielded about 8 mm FWHM with NaI detector [13].…”

“…In current SPECT scanners, cadmium zinc telluride (CZT) semiconductor detectors have been applied to improve energy and spatial resolution [4][5][6][7][8], as compared with sodium iodide (NaI) scintillation detectors, which were used in conventional SPECT scanners [9][10][11][12][13][14][15][16][17][18][19]. Planar and SPECT projection data are acquired using various collimators in clinical settings.…”

“…Planar and SPECT projection data are acquired using various collimators in clinical settings. Almost all small-animal SPECT is performed with pinhole collimators (PH), including single-PH (SPH) [8,[12][13][14][15][16][17] and multi-PH (MPH) [6,[8][9][10]15], as these collimators will provide good resolution for small objects when compared with parallel hole collimators (PAH), which are more commonly used in clinical settings [20]. Although we have to select appropriate collimator to obtain high-quality images and accurate analysis results, there have been no comparative studies on image quality with various collimators in small animal imaging.…”