Symbia t6 spect ct system

Patients were assessed by MP-SPECT using a Symbia T6 SPECT-CT system (Siemens, Erlangen, Germany; Siemens Japan, Tokyo, Japan). The equipment consisted of a dual-head gamma camera in 180° geometry equipped with a low-energy, high-resolution (LEHR) collimator. The SPECT data were acquired in a 64 × 64 matrix using the following parameters: zoom, × 1.45; pixel size, 6.6 mm, duration, and 35 s per projection for a total acquisition period of 20 min. We obtained a total of 60 frames, at 6° per step over 360°. The cardiac cycle was divided into 16 frames for electrocardiography (ECG) gating. R-R intervals that averaged ± 25% on the ECG monitor were accepted for gating. The energy was centered at 140 keV, with a 15% window for SPECT/CT imaging. Scatter and attenuation were not corrected. The detectors were placed close to the patient in circular mode at a radius of 24–25 cm.

SPECT/CT imaging of the abdomen was performed 24 hours after the injection of the radiotherapeutic agent. The images were acquired with a Symbia T6 SPECT/CT system (Siemens Healthineers AG, Erlangen, Germany; matrix: 128 × 128; 64 views of 20 seconds). SPECT images were reconstructed with an OSEM-based Flash 3D algorithm (8 iterations, 4 subsets, and 8 mm Gaussian filtering). For ⁹⁰Y/¹¹¹In-DOTATOC, a scatter and attenuation correction was performed. Additionally, at 3 and 48 hours postinjection (p.i.), scintigraphy was performed to monitor radiation exposure of the kidneys and whole body assessment, respectively.

A dual-head Symbia T6 SPECT/CT system (Siemens Healthineers, Erlangen, Germany) with a NaI crystal thickness of 9.5 mm and equipped with a medium energy low penetration collimator was used.