Erschienen in:
01.02.2017 | Short Communication
Optimization of scan initiation timing after 11C-methionine administration for the diagnosis of suspected recurrent brain tumors
verfasst von:
Reiko Nakajima, Koichiro Abe, Mitsuru Momose, Kenji Fukushima, Yuka Matsuo, Ken Kimura, Chisato Kondo, Shuji Sakai
Erschienen in:
Annals of Nuclear Medicine
|
Ausgabe 2/2017
Einloggen, um Zugang zu erhalten
Abstract
Objective
11C-Methionine (MET) positron emission tomography (PET) imaging is a valuable technique for the evaluation of primary and recurrent brain tumors. Many studies have used MET-PET for data acquisition starting at 20 min after the tracer injection, while others have used scan initiation times at 5–15 min postinjection. No previous studies have identified the best acquisition timing during MET-PET imaging for suspected recurrent brain tumors. Here we sought to determine the optimal scan initiating timing after MET administration for the detection of recurrent brain tumors.
Materials and methods
Twenty-three consecutive patients with suspected recurrent brain tumors underwent MET-PET examinations. Brain PET images were reconstructed from the four serial data sets (10–15, 15–20, 20–25, and 25–30 min postinjection) that were obtained using the list-mode acquisition technique. We determined the maximal standardized uptake values (SUVmax) of the target lesions and the target-to-normal-tissue ratios (TNRs), calculated as the SUVmax to the SUVmean of a region of interest placed on the normal contralateral frontal cortex. Target lesions without significant MET uptake were excluded.
Results
Thirty-one lesions from 23 patients were enrolled. There were no significant differences in MET SUVmax or TNR values among the PET images that were reconstructed with the data extracted from the four phases postinjection.
Conclusion
The MET uptake in the suspected recurrent brain tumors was comparable among all data extraction time phases from 10 to 30 min postinjection. The scan initiation time of MET-PET at 10 min after the injection is allowable for the detection of recurrent brain tumors. The registration identification number of the original study is 1002.