Impact of Reduced Acquisition Time on Bone Single-photon Emission Computed Tomography Images in Oncology PatientsNusret Salkica, Amela Begic, Sandra Zubovic, Sejla Ceric, Amila Basic, Adnan Sehic, Fuad Julardzija, Enis Tinjak.
Background: The use of resolution recovery (RR) in bone and myocardial perfusion imaging is becoming increasingly popular in nuclear medicine departments. RR produces reconstructed images that show improved spatial resolution and signal-to-noise ratio compared with conventional single-photon emission computed tomography (SPECT) images. Objective: To evaluate the impact of the ordered subset expectation maximization (OSEM) RR modality on preserving noise, signal-to-noise ratio (SNR), and contrast-to-noise ratio (CNR) for short SPECT acquisition. Methods: This prospective study was conducted on 80 patients. Full SPECT acquisition was performed as a standardized protocol, while reduced acquisition was achieved with the Poisson resampling method. Noise, SNR, and CNR were measured for different reconstruction parameters for the same image levels. The impact of surface area and body mass index was also measured for the same reconstruction parameters. Results: The results show significantly higher SNR and CNR for the Evolution for Bone protocol compared to the other two reconstruction protocols for full and reduced SPECT acquisition. With the shortening of the SPECT acquisition, an increase in the value of noise was recorded. SNR and CNR decreased with the reduction in SPECT acquisition. Conclusion: The Evolution for Bone protocol for all three analyzed acquisition protocols had the lowest noise values. The highest SNR and CNR were recorded in the Evolution for Bone protocol for the three acquisition protocols and SPECT acquisition time can be reduced from 20 to 10 min for bone SPECT.
Key words: SPECT, SNR, CNR, OSEM, RR.