Radiosurgery for Trigeminal Neuralgia Secondary to Dolichoectatic Vessels: Case Series and Review of Literature

Abstract

Even for seasoned neurosurgeons who have mastered the microvascular decompression (MVD) techniques, trigeminal neuralgia (TGN) secondary to vertebrobasilar dolichoectatic vessels remains a challenge. Often, patient is either medically infirm or unwilling for invasive surgical interventions. Alternative treatment options including Gamma Knife radiosurgery (GKRS) are considered in such a situation with variable success. This study aimed to evaluate the role of GKRS in patients with trigeminal neuralgia with dolichoectatic vessels and severe cross compression. We prospectively managed three male patients of intractable TGN secondary to dolichoectatic vascular compression with single-session GKRS. The cisternal component of the trigeminal nerve was targeted with 90 Gy radiation at 100% isodose with a single 4-mm collimator. The patients were regularly evaluated on clinical parameters for pain relief (Barrow Neurological Institute (BNI) score), sensory complaints, and outcome. All patients had satisfactory pain control (BNI I-IIIa) at 3 months of interval only to get recurrent pain (BNI IV-V) after 6 months. The treatment was eventually considered a failure after 6-month duration and one patient needed MVD for pain control. Post-GKRS pain control remains inferior in patients with dolichoectasia compared with typical TGN. GKRS should be offered only as a salvage or rescue procedure and should not be used as an alternative treatment of MVD in patient population with dolichoectatic vessels.