TY - JOUR T1 - Imaging of cerebral oxygen metabolism in the rat brain: An integrated PET/MRI study with O15-labelled gas JF - Journal of Nuclear Medicine JO - J Nucl Med SP - 1179 LP - 1179 VL - 52 IS - supplement 1 AU - Tadashi Watabe AU - Eku Shimosegawa AU - Yasukazu Kanai AU - Hiroshi Watabe AU - Masao Imaizumi AU - Seiichi Yamamoto AU - Hiroki Kato AU - Mitsuaki Tatsumi AU - Jun Hatazawa Y1 - 2011/05/01 UR - http://jnm.snmjournals.org/content/52/supplement_1/1179.abstract N2 - 1179 Objectives The purpose of this study was to evaluate cerebral oxygen metabolism and blood flow in normal rats with O15-labelled gas by means of integrated PET/MRI system (iPET/MRI). Methods Under midazolam and xylazine anesthesia, tracheotomy was performed in 3 normal rats (9 weeks old, body weight=285.8±4.9g). Artificial ventilation of O2 gas with 15O-CO, 15O-O2, and 15O-CO2 (approximately 100-250MBq/min, 240ml/min) were performed in order. Simultaneous measurements of PET and MRI (FLASH: TR=50, TE=5) were started with administration of each 15O-labelled gas for 7-12 min. PET/MRI fusion images were used to evaluate whether the tracer accumulation was corresponded to the brain. Results The study procedure was done within 60 min. In both 15O-O2 and 15O-CO2 study, true coincidence count of head reached steady state after approximately 7 min of continuous inhalation and PET images during steady state acquisition clearly showed high uptake in the cerebrum and cerebellum accurately corresponding to the MRI images. The highest uptake was found in the basal ganglia and thalamus. In 15O-CO study, high uptake was observed in venous sinus and bilateral internal/external carotid vein. Conclusions iPET/MRI demonstrated visualization of cerebral oxygen metabolism and blood flow in normal rats. The present results facilitate quantitative measurement of cerebral oxygen metabolic rate and cerebral blood flow in the rat experiment ER -