Satisfied quantitative value can be acquired by short-time bone SPECT/CT using a whole-body cadmium–zinc–telluride gamma camera

Abstract

The aim of this study was to evaluate the quantitative values of short-time scan (STS) of metastatic lesions compared with a standard scan (SS) when acquired by whole-body bone SPECT/CT with cadmium–zinc–telluride (CZT) detectors. We retrospectively reviewed 13 patients with bone metastases from prostate cancer, who underwent SPECT/CT performed on whole-body CZT gamma cameras. STSs were obtained using 75, 50, 25, 10, and 5% of the list-mode data for SS, respectively. Regions of interest (ROIs) were set on the increased uptake areas diagnosed as metastases. Intraclass correlation coefficients (ICCs) of standardized uptake values (SUVs) for the ROIs were calculated between the SS and each STS, and ICC ≥ 0.8 was set as a perfect correlation. Moreover, the repeatability coefficient (RC) was calculated, and RC ≤ 20% was defined as acceptable. A total of 152 metastatic lesions were included in the analysis. The ICCs between the SS vs. 75%-STS, 50%-STS, 25%-STS, 10%-STS, and 5%-STS were 0.999, 0.997, 0.994, 0.983, and 0.955, respectively. The RCs of the SS vs. 75%-STS, 50%-STS, 25%-STS, 10%-STS, and 5%-STS were 7.9, 12.4, 19.8, 30.8, and 41.3%, respectively. When evaluating the quality of CZT bone SPECT/CT acquired by a standard protocol, 25%-STS may provide adequate quantitative values.

Detection of prostate cancer bone metastases with fast whole-body 99mTc-HMDP SPECT/CT using a general-purpose CZT system

“…In line with a recent study [ 23 ], the results of SUV and lesion volume measurements were not affected by changes in the acquisition parameters. SUV peak with a 256 × 256 matrix was the only exception, but this can be explained by the difference in voxel size between 128 × 128 and 256 × 256 matrices, which causes different actual volumes for the 1 cm 3 cube used for measuring SUV peak .…”

“…SUV peak with a 256 × 256 matrix was the only exception, but this can be explained by the difference in voxel size between 128 × 128 and 256 × 256 matrices, which causes different actual volumes for the 1 cm 3 cube used for measuring SUV peak . Moreover, the repeatability of SUV and lesion volume measurements is expected to decrease as image noise increases [ 23 ].…”

Improving the image quality of short-time bone SPECT using CZT detectors with SwiftScan

“…Ten patients with bone metastases from prostate cancer who underwent list-mode SPECT/CT imaging with a whole-body semiconductor camera at our hospital between December 2019 and February 2022 were included. The results from 10 of the 13 patients participated in a previous case study [10] were also evaluated. Because a long acquisition time is usually mandatory in the standard SPECT imaging protocol, we evaluated the data of 10 patients who were imaged using three or fewer steps, which is inconvenient for patients experiencing pain.…”

“…Furthermore, GE Healthcare's gamma camera is equipped with a new feature called SwiftScan, which allows data to be collected while the detector is moving. The use of SwiftScan may further reduce collection time; however, the aforementioned study [10] did not examine this function or its quantitative effects. Therefore, the present study aimed to evaluate the quality and associated quantitative value of SwiftScan in short-time bone SPECT using a CZT camera.…”

“…Compared with conventional scintillation cameras, semiconductor cameras with cadmium-zinc-telluride (CZT) detectors have high energy and spatial resolution; therefore, they reduce the amount of contrast agent injected and shorten the tast time [1] [8] [9]. The clinical evaluation of short-time bone SPECT/CT acquisition with whole-body CZT detectors has been reported [10]. Furthermore, GE Healthcare's gamma camera is equipped with a new feature called SwiftScan, which allows data to be collected while the detector is moving.…”