Évaluation de la modalité de reconstruction xSPECT bone dans la détection de lésions osseuses secondaires en scintigraphie osseuse

Abstract

IntroductionThe xSPECT Bone® (xB) algorithm modifies the distribution of scintigraphic information using CT combined with SPECT in order to improve spatial resolution. It could help to detect bone lesions, especially malignant ones. We evaluated its ability to highlight malignant bone lesions compared with conventional reconstruction, and studies the discrepancies between the two reconstruction modalities. MethodForty-seven patients who underwent SPECT-CT for oncology purpose were retrospectively included. Images (Symbia Intevo T6 camera; Siemens) were reconstructed with xB and a conventional iterative algorithm (F3D), and interpreted by two nuclear medicine physicians. Bone lesions and malignant ones were identified (with a diagnostic reference established by consensus after rereading of doubtful lesions and analysis of the patients’ records). ResultsF3D allowed to detect more lesions than xB. In a per-lesion analysis, F3D showed better interobserver agreement than xB (p = 0.02) but overall diagnostic performance was equivalent. More malignant lesions were detected with F3D only, than with xB only (p<0.01), and these discordances did not involve any particular bone segment. Enhancement of healthy bone structures or decrease in contrast related to xSPECT reconstruction (OSCGM) could decrease contrast in xB. ConclusionMore lesions were detected with F3D than with xB, but overall diagnostic performance seems equivalent.