Navigating precision: Anatomical insights into the efficacy of masks versus stereotactic frames in icon gamma knife treatment for trigeminal neuralgia.

Background: The trigeminal nerve is approximately 2 mm in thickness. Its location is critical due to the alignment of the brain stem. Hence, precise fixation during the gamma knife (GK) treatment is particularly important. This study aimed to compare the effectiveness of mask fixation compared to frame fixation during the irradiation of trigeminal neuralgia (TN) treatment.

Methods: A prospective clinical study involving 135 patients with essential TN in Baghdad, Iraq, was conducted from January to July 2024. The study used two head fixation methods: stereotactic frames and plastic masks. Patients were treated with an Icon version of the GK, with no previous radiation treatment. Patients were diagnosed with 3 Tesla magnetic resonance imaging and assessed using the Barrow Neurological Institute (BNI) score before treatment. Clinical response was assessed at 3-month intervals. Ethical consent was obtained from all patients involved.

Results: This study analyzed the socio-demographic parameters of patients with TN and found that females were more prevalent. 5.2% of patients underwent glycerol injection, while 2.9% underwent microvascular decompression surgery. The BNI score was formulated for fixation methods, with frame fixation with screws and local anesthesia reaching IV and V scores. The response of TN patients to GK treatment was assessed using the BNI score before and after three months. Most patients showed pain relief, with 17.9% having a complete response. A Chi-square statistical analysis showed no significant difference between frame and mask fixation.

Conclusion: There was no significant difference in the precision of frame fixation compared to the plastic mask fixation for TN. The mask is as efficient as the frame.