Juan B Cortina, Julieta M Silva, Gonçalo Fernandes, Begoña Cattoni, Jose Manuel Brás Cuf, GammaKnife, Lisbon, Portugal

Topic

Clinical: CNS

Keywords

GammaKnife, trigeminal, neuralgia.

Purpose/Objective

Several potentially successful surgical modalities are available to patients with medically refractory Trigeminal Neuralgia (TN). Gamma Knife (GK) is an established therapeutic option for patients with TN. A handful of studied have shown the efficacy of GK but de follow-up has been short. We report a retrospective review of 59 patients with a median follow-up of 60 months.

Material/Methods

A retrospective review was conducted for 59 patients who underwent GK for refractory TN at our institution between 2010 and 2023. TN received GK with a mean marginal radiation dose of 42,5 Gy applied to an average isodose line of 50% of the affected trigeminal nerve. Follow-up data were obtained by clinical examination and telephone questionnaire. Outcomes results were evaluated using the Barrow Neurological Institute (BNI) Pain Scale. BNI I-III was considered to be a good outcome and BNI IV-V considered a treatment failure.

Results

The median follow-up was 60 months. Of the total 59 patients, 30 (50,8%) had good outcomes, reported as pain relief within 1 month following de GK treatment. A total of 8 patients (13,6%) experienced complete pain relief off medications (BIN I). At median followup of 60 months, the actuarial rate of freedom from severe pain (BIN>=III) was 27,1%. 21 patients were subjected to a previous surgical treatment. 14 patients were taking more than 3 drugs. 5 patients developed new or increased facial paresthesias after radiosurgery (12,2%).

Conclusion

GK radiosurgery is a minimally invasive technique to treat TN, safe and effective. It is associated with a low risk of facial paresthesias and approximately half patients experienced pain relief