RT Journal Article
SR Electronic
T1 Quantitative bone SPECT with a novel multimodal reconstruction
JF Journal of Nuclear Medicine
JO J Nucl Med
FD Society of Nuclear Medicine
SP 338
OP 338
VO 54
IS supplement 2
A1 Michal Cachovan
A1 Alexander Hans Vija
A1 Joachim Hornegger
A1 Torsten Kuwert
YR 2013
UL http://jnm.snmjournals.org/content/54/supplement_2/338.abstract
AB 338 Objectives A new, truly hybrid multimodal reconstruction method has been developed that enables High-Definition Bone and Quantitative-SPECT imaging (HD-Bone, Q-SPECT; Siemens Healthcare). The aim of this study is to compare bone tracer activity concentration (AC) provided by Q-SPECT/HD-Bone (QHDB) with OSEM-based Flash3D (F3D), which is in clinical use. Methods Eight female patients (64.25 ± 17.94 y; injected dose 537 ± 82 MBq) underwent a SPECT/CT scan of the lumbar region 4 hours ± 30 minutes post injection of Tc-99m-diphosphonate. The Siemens Symbia SPECT/CT system used was cross calibrated against our well counter. Images were reconstructed with both F3D and QHDB. Both algorithms use 3D resolution recovery, scatter and CT-based attenuation correction. However, QHDB utilizes a more accurate system model than F3D and reports AC in units of Bq/ml in contrast to counts reported by F3D. The conversion method to convert F3D data to Bq/ml is described in [1]. AC and CT tissue density in Hounsfield Units (HU) were collected in VOIs drawn over the three lower lumbar vertebrae. In addition, standardized uptake values (SUV) were computed. Together, 21 healthy vertebrae, diagnosed free of focal SPECT and CT pathology, were selected. Results The average AC for F3D was 51.87 ± 17.38 kBq/ml (95 % confidence interval (CI) 44.00-59.74 kBq/ml) corresponding to an average SUV of 6.41 ± 1.71 (95 % CI 5.63-7.18 SUV). QHDB results showed an average activity of 56.70 ± 17.21 kBq/ml (95 % CI 48.87-64.53 kBq/ml) and an average SUV of 7.02 ± 1.67 (95 % CI 6.26-7.78 SUV). For both reconstructions SUV correlated significantly with HU (F3D: r=0.536, p<0.05; QHDB: r=0.643, p<0.005). Both F3D and QHDB AC values correlated significantly (r=0.967, p<0.0001). Conclusions The results show a high correlation between Flash3D and quantitative HD-Bone with regard to the measurement of regional AC. Tracer uptake correlated with bone density which underlines the physiological significance of this variable. Our data suggest that quantitative HD-Bone can be utilized for quantitative bone SPECT.