Gamma knife radiosurgery for trigeminal neuralgia: is anterior selective targeting a reasonable alternative?

PURPOSE: To compare clinical outcomes and complication profiles of the anterior selective targeting (AST), which selectively targets the V2-V3 preganglionic region to minimize V1 exposure, versus dorsal root entry zone targeting (DREZ) in trigeminal neuralgia (TN). MATERIAL AND METHODS: We retrospectively analyzed 34 medically refractory TN patients treated with Gamma Knife radiosurgery (GKRS) at the Gamma Knife Radiosurgery Centre of Gazi University (January 2022-April 2023). Target selection was non-randomized and based on dermatomal symptoms and MRI anatomy: AST was used in patients without V1 involvement when trigeminal divisions could be confidently separated within Meckel's cave on 1.5-T MRI; otherwise, DREZ targeting was performed. GKRS was delivered using a single 4-mm collimator shot with 43 Gy prescribed to the 50% isodose line. At 12 months, outcomes included changes in Visual Analog Scale (VAS) and Barrow Neurological Institute (BNI) pain scores, BNI facial numbness score, corneal reflex status, medication changes, pain-free interval, subjective pain assessment, patient satisfaction, and beam-on time. RESULTS: < 0.001). CONCLUSION: In selected TN patients without V1 involvement, AST provides effective pain control with comparable 12-month outcomes to DREZ and shorter beam-on time. Given its relative distance from the brainstem and reduced V1 inclusion, AST may be considered for initial or repeat GKRS in selected cases.