Gamma knife radiosurgery targeting protocols for the experiments with small animals.
OBJECTIVE
Manipulation of brain functions via Gamma Knife (GK) irradiation would have numerous applications in clinical and experimental neurology.


METHODS
Alteration of brain functions in the unilaterally irradiated striatum was indexed through monitoring freely moving rat behaviors. Spontaneous activity and rotations on the apomorphine test, which can detect dopaminergic function imbalance, were indexed employing our behavior tracking system. The spatial distribution of necrotic lesions was explored using serial sections, and was assumed to represent the real foci of the GK target.


RESULTS
Distinct behavioral alterations corresponded to the precise locations of the lesions in various areas of the basal ganglia. Displacement of the irradiation sites in the anteromedial direction increased spontaneous activity, and posterolateral shift provoked circling behavior on the apomorphine test.


CONCLUSIONS
Accurate positioning of the target is crucial for experimental GK irradiation locally focused on domains of a small brain such as that of the rat. Here, we propose a protocol for converting the 'intended' focus, based on brain map coordinates, to a 'planned' focus on the MR imaging coordinate system with the Régis-Valliccioni stereotactic frame.
Tokumaru
Osamu
O
Department of Physiology, School of Medicine, Tokyo Women's Medical University, Tokyo, Japan.
Hayashi
Motohiro
M
Katayama
Yoko
Y
Tomida
Mihoko
M
Kawakami
Yoriko
Y
Kouyama
Nobuo
N
D000818:Animals; D001058:Apomorphine / Q000494:pharmacology; D001479:Basal Ganglia / Q000187:drug effects / Q000528:radiation effects / Q000601:surgery; D001522:Behavior, Animal / Q000187:drug effects / Q000528:radiation effects; D001931:Brain Mapping / Q000379:methods*; D002985:Clinical Protocols; D018491:Dopamine Agonists / Q000494:pharmacology; D005720:Gamma Rays / Q000009:adverse effects; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D016634:Radiosurgery / Q000379:methods*; D051381:Rats; D017208:Rats, Wistar; D013238:Stereotaxic Techniques
D018491:Dopamine Agonists; D001058:Apomorphine