Spect ct scanner

Twelve HepG2 tumor bearing mice were randomly divided into four groups (n = 3) and injected with ^99mTc-duramycin (37 MBq/2 μg/mouse) through the tail vein. Two hours after injection, mice were anesthetized using inhalation of 2% isoflurane. Then they were scanned in a simultaneous micro-single-photon emission computed tomography/computed tomography (SPECT/CT) scanner (Bioscan, Washington DC, USA). The SPECT/CT imaging parameters were as follow: SPECT: energy peak, 140 keV; scanning time, 35 s/projection; window width, 10%; resolution, 1 mm/pixel; and matrix, 256 × 256. CT: tube current, 0.15 mA; tube voltage, 45 keV; exposure time, 500 ms/frame, and frame resolution, 256 × 512. The HiSPECT algorithm was used for imaging reconstruction.
InVivoScope software (Version 1.43, Bioscan, Washington DC, USA) was used for imaging post-processing. Two 3D region of interest (ROI) were drawn in the region of the tumor and similar region on the contralateral muscle as background ROI. The concentration of radioactivity of each ROI (μCi/mm³) was determined using this software. The tumor-to-background ratio (T/B) was regarded to express tumor signal intensity with reducing inter-mice variations.

After anesthesia (i.p. injection of ketamine/xyzaline; 1.5 mL/kg, ratio 2:1), mice were injected with 18.5 MBq of ^99mTcO₄⁻ and scanned in a SPECT/CT scanner (Bioscan, Washington DC, USA). SPECT and CT images were acquired with different timing based on specific radioactive levels to obtain 100,000 c.p.s. Images were reconstructed with MEDISO software (Medical Imaging Systems, Budapest, Hungary) and fusion using PMOD software (PMOD Technologies Basel, Switzerland).