For patients that fail initial SRS for trigeminal neuralgia, what factors do you consider when considering re-irradiation?  

Failure within 6 months/No response: Is vascular compression present? Yes = Consider Microvascular decompression. If contraindicated repeat SRS to 50 Gy. No + then was the nerve clearly visualized on MRI? Yes = Possible repeat SRS to 50 Gy. No = then that could be a cause for failure, consi...