Appearance time of blood in the brain as a possible indicator of oxygen extraction fraction: a feasibility study

• Published in: EJNMMI research Vol. 14; no. 1; pp. 97 - 8
• Main Authors: Murao, Mitsumasa, Kudomi, Nobuyuki, Mitamura, Katsuya, Norikane, Takashi, Manabe, Yuri, Maeda, Yukito, Yamamoto, Yuka, Hatakeyama, Tetsuhiro, Nishiyama, Yoshihiro
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 16.10.2024; Springer Nature B.V; SpringerOpen
• Subjects: 15O-labelled tracer; Appearance time of blood; Blood flow; Brain; Cardiac Imaging; Cerebral blood flow; Consistency; Feasibility studies; Imaging; Medical imaging; Medicine; Medicine & Public Health; Nuclear Medicine; Oncology; Original Research; Orthopedics; Oxygen; Oxygen extraction fraction; Positron emission; Positron emission tomography; Radiology; Visual observation; O-labelled tracer; Cerebral blood flow; Positron emission tomography; Appearance time of blood; Oxygen extraction fraction; 15O-labelled tracer
• ISSN: 2191-219X; 2191-219X
• DOI: 10.1186/s13550-024-01160-z

Background Imaging examination of cerebral blood flow (CBF), oxygen extraction fraction (OEF), and metabolic rate of oxygen is crucial for understanding the normal functioning and pathophysiology of the brain. A recently developed method estimates the appearance time of cerebral blood (ATB) pixel-wise from the imaging examination of CBF alone. In this study, we aimed to test the potential of ATB as an indicator of OEF. Results We retrospectively reviewed patients ( n  = 62) with suspected cerebrovascular disorders including steno-occlusive disease who underwent positron emission tomography (PET) with 15 O-labelled tracers. Regarding the generated OEF and ATB images, a visual assessment was performed to test the consistency of the elevated OEF and delayed ATB. The OEF and ATB values and the absolute differences between their ipsilateral and contralateral sides were extracted and obtained for the entire hemisphere and the middle, anterior, and posterior cerebral arterial regions. Consistency was observed in 52 PET scans (83.9%) in visual assessment. The OEF and ATB values were moderately correlated ( r  = 0.553, p  < 0.001), and the differences between their ipsilateral and contralateral sides were weakly correlated ( r  = 0.276, p  < 0.001). Conclusion Our results indicate the potential of ATB as an indicator of OEF.