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Updated: Jul 16, 2026
Comprehensive Endovascular and Open Surgical Management of Cerebral Arteriovenous Malformations
Published on: October 20, 2017
Inhibition of angiogenesis induced by cerebral arteriovenous malformations using gamma knife irradiation
Kaya Kiliç1, Deniz Konya, Ozlem Kurtkaya
1Laboratory of Molecular Neurosurgery, Marmara University Institute of Neurological Sciences, Istanbul, Turkey.
Object:
The authors studied the effect of Gamma Knife irradiation on angiogenesis induced by cerebral arteriovenous malformation (AVM) tissues implanted in the corneas of rats.
Methods:
Ten AVM specimens obtained from tissue resections performed at Marmara University between 1998 and 2004 were used. A uniform amount of tissue was implanted into the micropocket between the two epithelial layers of the cornea. Gamma Knife irradiation was applied with dose prescriptions of 15 or 30 Gy to one cornea at 100% isodose. Dosing was adjusted so that the implanted cornea of one eye received 1.5 Gy when 15 Gy was applied to the other cornea. Similarly, one cornea received 3 Gy when 30 Gy was applied to the other cornea. Angiogenic activity was graded daily by biomicroscopic observations. Forty-eight other rats were used for microvessel counting and vascularendothelial growth factor (VEGF) staining portions of the experiment. Micropieces of the specimens were again used for corneal implantation. Rats from each group were killed on Days 5, 10, 15, and 20, and four corneas from each group were examined. Gamma Knife irradiation dose dependently decreased AVM-induced neovascularization in the rat cornea as determined by biomicroscopic grading of angiogenesis, microvessel count, and VEGF expression.
Conclusions:
The results suggest that Gamma Knife irradiation inhibits angiogenesis induced by AVM tissue in the cornea angiogenesis model. The data are not directly related to understanding how Gamma Knife irradiation occludes existing AVM vasculature, but to understanding why properly treated AVMs do not recur and do not show neovascularization after Gamma Knife irradiation.
Insights
Gamma Knife irradiation effectively inhibits new blood vessel growth (angiogenesis) in rat corneas caused by arteriovenous malformation (AVM) tissues. This study explains why treated AVMs do not show neovascularization post-treatment.
Area of Science:
- Ophthalmology
- Neurosurgery
- Vascular Biology
Background:
- Cerebral arteriovenous malformations (AVMs) are complex vascular abnormalities.
- Angiogenesis, the formation of new blood vessels, plays a role in AVM development and recurrence.
- Gamma Knife radiosurgery is a treatment modality for AVMs, but its anti-angiogenic effects require further elucidation.
Purpose of the Study:
- To investigate the anti-angiogenic effect of Gamma Knife irradiation on AVM-induced neovascularization.
- To evaluate the impact of Gamma Knife irradiation on vascular endothelial growth factor (VEGF) expression in a corneal angiogenesis model.
Main Methods:
- AVM tissue specimens were implanted into rat corneas to induce angiogenesis.
- Rats were subjected to Gamma Knife irradiation at varying doses (15 Gy and 30 Gy).
- Angiogenesis was assessed through daily biomicroscopic observations, microvessel counting, and VEGF staining.
Main Results:
- Gamma Knife irradiation demonstrated a dose-dependent decrease in AVM-induced neovascularization.
- Biomicroscopic grading, microvessel counts, and VEGF expression were significantly reduced following irradiation.
- The study confirmed the inhibitory effect of Gamma Knife irradiation on angiogenesis in this model.
Conclusions:
- Gamma Knife irradiation effectively inhibits angiogenesis induced by AVM tissue in a rat cornea model.
- The findings support the understanding of why treated AVMs exhibit reduced recurrence and neovascularization.
- This research provides insights into the mechanisms underlying the efficacy of Gamma Knife radiosurgery for AVMs.
