title: Hyperperfusion and hypermetabolism in brain radiation necrosis with epileptic activity.
abstract: We report a case of high uptake of 11C-methionine (MET), 18F-FDG (FDG) and 201Tl-Cl (Tl) in brain radiation necrosis. Twenty-one years previously, the patient had undergone surgery and radiation therapy consisting of 60-Gy for ependymoma in the anterior horn of the right lateral ventricle. The clinical features consisting of frequent seizures of the left face and arm suddenly appeared 2 wk before admission. MRI depicted a Tl and T2-prolonged lesion in the right frontal lobe. Abnormally high uptake in this area demonstrated by MET-PET, FDG-PET, Tl-SPECT or HMPAO-SPECT suggested the presence of a recurrent tumor. A craniotomy was then performed and an intraoperative electrocorticogram showed continuous epileptic spikes in the lesion. The epileptic foci were resected and the histological features of the lesion were consistent with radiation necrosis. After surgery, the seizures disappeared and the postoperative examinations with MET-PET, FDG-PET, Tl-SPECT and HM-PAO-SPECT no longer showed abnormally high uptake. Hypermetabolism and hyperperfusion related to epileptic fits are therefore thought to result in high uptake of MET, FDG and Tl in radiation necrosis.
authors.affiliation: Department of Radiology, Faculty of Medicine, Kyushu University, Fukuoka, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Sasaki
authors.forename: Y
authors.initials: Y
authors.lastname: Ichiya
authors.forename: Y
authors.initials: Y
authors.lastname: Kuwabara
authors.forename: T
authors.initials: T
authors.lastname: Yoshida
authors.forename: T
authors.initials: T
authors.lastname: Inoue
authors.forename: T
authors.initials: T
authors.lastname: Morioka
authors.forename: K
authors.initials: K
authors.lastname: Hisada
authors.forename: M
authors.initials: M
authors.lastname: Fukui
authors.forename: K
authors.initials: K
authors.lastname: Masuda
mesh_terms: D000328:Adult; D001921:Brain / Q000000981:diagnostic imaging* / Q000473:pathology / Q000528:radiation effects; D001932:Brain Neoplasms / Q000532:radiotherapy; D003847:Deoxyglucose / Q000031:analogs & derivatives; D004806:Ependymoma / Q000532:radiotherapy; D017034:Epilepsy, Frontal Lobe / Q000000981:diagnostic imaging / Q000209:etiology*; D005260:Female; D005462:Fluorine Radioisotopes; D019788:Fluorodeoxyglucose F18; D006801:Humans; D008715:Methionine; D009336:Necrosis; D015609:Organotechnetium Compounds; D010091:Oximes; D011832:Radiation Injuries / Q000150:complications / Q000000981:diagnostic imaging*; D019690:Technetium Tc 99m Exametazime; D013794:Thallium Radioisotopes; D013997:Time Factors; D014055:Tomography, Emission-Computed; D015899:Tomography, Emission-Computed, Single-Photon
chemical_list: D005462:Fluorine Radioisotopes; D015609:Organotechnetium Compounds; D010091:Oximes; D013794:Thallium Radioisotopes; D019788:Fluorodeoxyglucose F18; D019690:Technetium Tc 99m Exametazime; C086242:carbon-11 methionine; D003847:Deoxyglucose; D008715:Methionine