title: Hypoxic viable tissue in human chronic cerebral ischemia because of unilateral major cerebral artery steno-occlusive disease.
abstract: OBJECTIVE
  Positron emission tomography (PET) with radiolabeled 2-nitroimidazoles directly detects hypoxic but viable tissue present in an acute ischemic area in the human brain. This study using PET with 1-(2-(18)F-fluoro-1-[hydroxymethyl]ethoxy) methyl-2-nitroimidazole ((18)F-FRP170) aimed to determine whether tissue with an abnormally elevated uptake of (18)F-FRP170 exists in human chronic cerebral ischemia because of unilateral atherosclerotic major cerebral artery steno-occlusive disease.
  
  
  METHODS
  (18)F-FRP170 PET was performed, and cerebral blood flow and metabolism were assessed using (15)O-gas PET in 20 healthy subjects and 52 patients. A region of interest (ROI) was automatically placed in 3 segments of the middle cerebral artery territory in both cerebral hemispheres with a 3-dimensional stereotaxic ROI template using SPM2, and each PET value was determined in each ROI. The ratio of values in the affected versus contralateral hemispheres was calculated for the (18)F-FRP170 PET image.
  
  
  RESULTS
  A significant correlation was observed between oxygen extraction fraction and (18)F-FRP170 ratios (ρ=0.509; P<0.0001) in a total of 156 ROIs in 52 patients. The specificity and positive-predictive value for a combination of an elevated oxygen extraction fraction and a moderately reduced cerebral oxygen metabolism for detection of an abnormally elevated (18)F-FRP170 ratio (19 ROIs: 12%) were significantly greater than those for the individual categories (elevated oxygen extraction fraction, moderately reduced cerebral oxygen metabolism, or reduced cerebral blood flow).
  
  
  CONCLUSIONS
  Tissues with abnormally elevated uptake of (18)F-FRP170 exist in human chronic cerebral ischemia characterized by a combination of misery perfusion and moderately reduced oxygen metabolism because of unilateral atherosclerotic major cerebral artery steno-occlusive disease.
authors: From the Department of Neurosurgery (H.S., K.O., T.B., Koji Yoshida, M.K., Kenji Yoshida, A.O.) and Cyclotron Research Center (K.T.), School of Medicine, Iwate Medical University, Morioka, Japan; and Department of Radiology and Radiation Oncology, Hirosaki University Graduate School of Medicine, Hirosaki, Japan (Y.T.). hirosau33@gmail.com.
authors: Hiroaki
authors: H
authors: Saura
authors: From the Department of Neurosurgery (H.S., K.O., T.B., Koji Yoshida, M.K., Kenji Yoshida, A.O.) and Cyclotron Research Center (K.T.), School of Medicine, Iwate Medical University, Morioka, Japan; and Department of Radiology and Radiation Oncology, Hirosaki University Graduate School of Medicine, Hirosaki, Japan (Y.T.).
authors: Kuniaki
authors: K
authors: Ogasawara
authors: From the Department of Neurosurgery (H.S., K.O., T.B., Koji Yoshida, M.K., Kenji Yoshida, A.O.) and Cyclotron Research Center (K.T.), School of Medicine, Iwate Medical University, Morioka, Japan; and Department of Radiology and Radiation Oncology, Hirosaki University Graduate School of Medicine, Hirosaki, Japan (Y.T.).
authors: Takaaki
authors: T
authors: Beppu
authors: From the Department of Neurosurgery (H.S., K.O., T.B., Koji Yoshida, M.K., Kenji Yoshida, A.O.) and Cyclotron Research Center (K.T.), School of Medicine, Iwate Medical University, Morioka, Japan; and Department of Radiology and Radiation Oncology, Hirosaki University Graduate School of Medicine, Hirosaki, Japan (Y.T.).
authors: Koji
authors: K
authors: Yoshida
authors: From the Department of Neurosurgery (H.S., K.O., T.B., Koji Yoshida, M.K., Kenji Yoshida, A.O.) and Cyclotron Research Center (K.T.), School of Medicine, Iwate Medical University, Morioka, Japan; and Department of Radiology and Radiation Oncology, Hirosaki University Graduate School of Medicine, Hirosaki, Japan (Y.T.).
authors: Masakazu
authors: M
authors: Kobayashi
authors: From the Department of Neurosurgery (H.S., K.O., T.B., Koji Yoshida, M.K., Kenji Yoshida, A.O.) and Cyclotron Research Center (K.T.), School of Medicine, Iwate Medical University, Morioka, Japan; and Department of Radiology and Radiation Oncology, Hirosaki University Graduate School of Medicine, Hirosaki, Japan (Y.T.).
authors: Kenji
authors: K
authors: Yoshida
authors: From the Department of Neurosurgery (H.S., K.O., T.B., Koji Yoshida, M.K., Kenji Yoshida, A.O.) and Cyclotron Research Center (K.T.), School of Medicine, Iwate Medical University, Morioka, Japan; and Department of Radiology and Radiation Oncology, Hirosaki University Graduate School of Medicine, Hirosaki, Japan (Y.T.).
authors: Kazunori
authors: K
authors: Terasaki
authors: From the Department of Neurosurgery (H.S., K.O., T.B., Koji Yoshida, M.K., Kenji Yoshida, A.O.) and Cyclotron Research Center (K.T.), School of Medicine, Iwate Medical University, Morioka, Japan; and Department of Radiology and Radiation Oncology, Hirosaki University Graduate School of Medicine, Hirosaki, Japan (Y.T.).
authors: Yoshihiro
authors: Y
authors: Takai
authors: From the Department of Neurosurgery (H.S., K.O., T.B., Koji Yoshida, M.K., Kenji Yoshida, A.O.) and Cyclotron Research Center (K.T.), School of Medicine, Iwate Medical University, Morioka, Japan; and Department of Radiology and Radiation Oncology, Hirosaki University Graduate School of Medicine, Hirosaki, Japan (Y.T.).
authors: Akira
authors: A
authors: Ogawa
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001157:Arterial Occlusive Diseases / Q000000981:diagnostic imaging / Q000473:pathology*; D001923:Brain Chemistry; D002545:Brain Ischemia / Q000000981:diagnostic imaging / Q000473:pathology*; D002539:Cerebral Arterial Diseases / Q000000981:diagnostic imaging / Q000473:pathology*; D002560:Cerebrovascular Circulation; D002908:Chronic Disease; D005260:Female; D006801:Humans; D000860:Hypoxia / Q000000981:diagnostic imaging / Q000473:pathology*; D020244:Infarction, Middle Cerebral Artery / Q000000981:diagnostic imaging / Q000473:pathology; D008297:Male; D008875:Middle Aged; D009593:Nitroimidazoles; D010101:Oxygen Consumption; D010104:Oxygen Radioisotopes; D049268:Positron-Emission Tomography; D011237:Predictive Value of Tests; D019275:Radiopharmaceuticals
chemical_list: C501635:FRP-170; D009593:Nitroimidazoles; D010104:Oxygen Radioisotopes; D019275:Radiopharmaceuticals
keywords: cerebrovascular disease; positron-emission tomography