Delayed cyst formation following ventral intermediate nucleus thalamotomy by Gamma Knife radiosurgery for essential tremor: illustrative case

Delayed cyst formation may occur many years after GKRS VIM thalamotomy and should be recognized as a rare but clinically significant late complication. Given the typical 7- to 10-year latency observed across radiosurgical cystogenesis, long-term but low-frequency MRI surveillance, such as a 1-year posttreatment baseline followed by imaging every 2-3 years or sooner with new neurological symptoms, may facilitate earlier detection and intervention. https://thejns.org/doi/10.3171/CASE25725.