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?

1. Yes = Consider Microvascular decompression. If contraindicated repeat SRS to 50 Gy.
2. No + then was the nerve clearly visualized on MRI?
   1. Yes = Possible repeat SRS to 50 Gy.
   2. No = then that could be a cause for failure, consider ret...