Experimental analysis of radiation dose distribution in radiosurgery: I. Dose hot spot inside target volume.
BACKGROUND
Radiosurgery is currently performed with different systems of focused radiation providing different dose heterogeneities within the target volume. Here, we aimed to study histological consequences of different dose distributions inside the target area in an experimental model of Gamma Knife irradiation in the rat striatum.


METHODS
Twelve rats were irradiated by Gamma Knife at the same volume in the right striatum; the same margin dose of 45 Gy was prescribed for all rats. Three different dose distributions inside the target volume were applied. Brain sections at the level of the target area were histologically analyzed 3 months after irradiation.


RESULTS
Of the 7 histopathological reactions found as a consequence of the irradiation, 6 of them were significantly related to the gradient of dose heterogeneity within the target volume.


CONCLUSIONS
Dose distribution inside the target volume could influence the histological effects of radiosurgical irradiation on tissue included in the target. A high dose in the target volume is more likely to lead to the desired radiobiological result.
Massager
Nicolas
N
Gamma Knife Center, Department of Neurosurgery, University Hospital Erasme, Brussels, Belgium. nmassage@ulb.ac.be
Maris
Calliope
C
Nissim
Ouzi
O
Devriendt
Daniel
D
Salmon
Isabelle
I
Levivier
Marc
M
D000818:Animals; D001706:Biopsy; D003342:Corpus Striatum / Q000473:pathology* / Q000601:surgery*; D004195:Disease Models, Animal; D005260:Female; D011183:Postoperative Complications / Q000473:pathology; D011829:Radiation Dosage; D011832:Radiation Injuries / Q000473:pathology*; D016634:Radiosurgery / Q000009:adverse effects* / Q000379:methods; D051381:Rats; D017208:Rats, Wistar