title: Cognitive dysfunction might be improved in association with recovered neuronal viability after intracranial meningioma resection.
abstract: Intracranial meningiomas are the most common types of neoplasms that cause mental disorders. Although higher brain function can be restored and even improved in some patients after tumor resection, the mechanisms remain unclear. We investigated changes in the brains of patients after resection of an intracranial meningioma using (123)I-Iomazenil (IMZ)-single photon emission computed tomography (SPECT). Ten patients underwent IMZ-SPECT within 4 weeks before and 3 months after intracranial meningioma resection. Changes in IMZ accumulation in brain parenchyma were assessed as ratios of counts in the lesion-to-contralateral hemisphere (L/C ratios). Mean Mini-Mental State Examination scores before and after resection of 19.9±11.4 vs. 26.5±3.8, respectively (p=0.03) indicated that the cognitive function of these patients was significantly improved after tumor resection. The average L/C ratios calculated from image counts of IMZ were 0.92±0.05 and 0.98±0.02 before and after surgery, respectively. The L/C ratio of IMZ accumulation was significantly decreased after tumor resection (p=0.0003). In contrast, regional cerebral blood flow calculated from (123)I-Iodoamphetamine-SPECT images did not significantly differ after tumor resection. The recovered binding potential of IMZ in brain parenchyma surrounding the tumor bulk after resection indicates that the viability of central benzodiazepine receptors was reversibly depressed and recoverable after release from compression by the tumor. The recovered neuronal viability revealed by IMZ-SPECT might be responsible for the improved cognitive function after intracranial meningioma resection.
authors.affiliation: Department of Neurosurgery, Yamaguchi University School of Medicine, Yamaguchi, Japan. Electronic address: hiroyasu@yamaguchi-u.ac.jp.
authors.forename: Hiroyasu
authors.initials: H
authors.lastname: Koizumi
authors.affiliation: Department of Neurosurgery, Yamaguchi University School of Medicine, Yamaguchi, Japan.
authors.forename: Makoto
authors.initials: M
authors.lastname: Ideguchi
authors.affiliation: Department of Radiology, Yamaguchi University School of Medicine, Yamaguchi, Japan.
authors.forename: Hideyuki
authors.initials: H
authors.lastname: Iwanaga
authors.affiliation: Department of Neurosurgery, Yamaguchi University School of Medicine, Yamaguchi, Japan.
authors.forename: Satoshi
authors.initials: S
authors.lastname: Shirao
authors.affiliation: Department of Neurosurgery, Yamaguchi University School of Medicine, Yamaguchi, Japan.
authors.forename: Hirokazu
authors.initials: H
authors.lastname: Sadahiro
authors.affiliation: Department of Neurosurgery, Yamaguchi University School of Medicine, Yamaguchi, Japan.
authors.forename: Fumiaki
authors.initials: F
authors.lastname: Oka
authors.affiliation: Department of Neurosurgery, Yamaguchi University School of Medicine, Yamaguchi, Japan.
authors.forename: Eiichi
authors.initials: E
authors.lastname: Suehiro
authors.affiliation: Department of Neurosurgery, Yamaguchi University School of Medicine, Yamaguchi, Japan.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Yoneda
authors.affiliation: Department of Neurosurgery, Yamaguchi University School of Medicine, Yamaguchi, Japan.
authors.forename: Hideyuki
authors.initials: H
authors.lastname: Ishihara
authors.affiliation: Department of Neurosurgery, Yamaguchi University School of Medicine, Yamaguchi, Japan.
authors.forename: Sadahiro
authors.initials: S
authors.lastname: Nomura
authors.affiliation: Department of Neurosurgery, Yamaguchi University School of Medicine, Yamaguchi, Japan.
authors.forename: Michiyasu
authors.initials: M
authors.lastname: Suzuki
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001921:Brain / Q000473:pathology / Q000503:physiopathology* / Q000601:surgery; D001932:Brain Neoplasms / Q000150:complications / Q000473:pathology / Q000503:physiopathology / Q000601:surgery*; D002470:Cell Survival; D002560:Cerebrovascular Circulation; D003072:Cognition Disorders / Q000209:etiology* / Q000473:pathology / Q000503:physiopathology*; D005260:Female; D005442:Flumazenil / Q000031:analogs & derivatives; D006801:Humans; D007457:Iodine Radioisotopes; D008279:Magnetic Resonance Imaging; D008297:Male; D008579:Meningioma / Q000150:complications / Q000473:pathology / Q000503:physiopathology / Q000601:surgery*; D008609:Mental Status Schedule; D008875:Middle Aged; D009474:Neurons / Q000502:physiology; D019275:Radiopharmaceuticals; D011963:Receptors, GABA-A / Q000378:metabolism; D015899:Tomography, Emission-Computed, Single-Photon; D016896:Treatment Outcome
chemical_list: D007457:Iodine Radioisotopes; D019275:Radiopharmaceuticals; D011963:Receptors, GABA-A; D005442:Flumazenil; C063038:iomazenil
keywords: Cerebral cortical neuron; Neurocognitive function; Radioligans