3525 - Radiosurgery Outcomes in Pure Venous Conflict Trigeminal Neuralgia Efficacy, Safety, and Long-term Outcomes
Presenter(s)
V. Shankar1, D. Arjundas2, S. Ghosh3, S. Cholayil1, S. Meenakshi Sundaram4, G. Laksmipathy5, A. V. Ramana Murthy6, D. Shyam4, V. L. Arulselvan7, V. R. Anand8, K. Bhanu9, S. Paramasivan10, S. Muthukani11, J. Verghese12, H. Sarkar13, and C. Haritha14; 1Apollo Cancer Centers, Chennai, India, 2Chief Neurologist, Mercury Hospital, Chennai, India, 3Dept. of Neurosurgery, Apollo Proton Cancer Center, Chennai, India, 4Apollo Speciality Hospitals, Madurai, India, 5Dept. of Neurology, Apollo Hospitals, Greams Unit, Chennai, India, 6Apollo Speciality Hospital, Nellore, India, 7Dept.of Neurology, Apollo Hospitals, Greams Unit, Chennai, India, 8Sai Neuro Hospital, Chennai, India, 9Mehtas Hospital, Chennai, India, 10Dept. of Neurosurgery, Apollo Hospitals, Greams Unit, Chennai, India, 11Dept. of Neurology, Apollo Hospitals, Greams Road, Chennai, India, 12Dept.of Neurosurgery, Apollo Hospitals, Greams unit, Chennai, India, 13Dept.of Neurosurgery, Apollo Hospitals, Greams Unit, Chennai, India, 14C.R.Reddy Cancer Center, Nellore, India
Purpose/Objective(s): Microvascular decompression (MVD) for trigeminal neuralgia (TGN) with pure venous conflict remains suboptimal due to anatomical and surgical challenges, including fragile veins, indistinct arachnoid planes, and risks of venous infarction or edema. This study evaluates the efficacy and safety of frameless stereotactic radiosurgery (SRS) in patients with TGN secondary to isolated venous neurovascular conflict.
Materials/Methods: From a prospectively maintained database of 420 patients treated with SRS for medically refractory TGN (2004–2024), 54 patients with isolated venous compression were analyzed. Inclusion criteria: (1) Type 2 TN (atypical pain), (2) MRV-confirmed venous compression (contrast-enhanced hyperintensity), and (3) absence of arterial compression on time-of-flight MR angiography (TOF-MRA).Patients underwent frameless SRS (or LINAC with stereotactic cones and 6-DOF image guidance), receiving 85 Gy to the retrogasserian target in the prepontine cistern.
Statistical Analysis: Kaplan-Meier estimated pain relief, Cox regression identified predictors, and Wilcoxon/Fisher’s exact tests analyzed outcomes (p < 0.05).
Results: The median age was 58.4 years (IQR: 52–64), with 34 females, 15 males. Mean symptom duration was 7.8 years (SD: ±2.5). All patients had diffuse V2/V3 involvement and poorly defined triggers. At median follow-up of 5.5 years, Kaplan-Meier analysis showed 70% probability of BNI I-II pain relief. The median time to pain relief was 3.5 months (95% CI: 2.8–4.3 months).
BNI outcomes at last follow-up:
- BNI I (pain-free, no medications): 40%
- BNI II (occasional pain, no medications): 30%
- BNI III (pain controlled with medications): 20%
- BNI IV (no relief): 10%
Predictors of favorable response (BNI I-II):
- Shorter symptom duration (<5 years) correlated with improved outcomes (HR: 1.92, 95% CI: 1.12–3.27, p = 0.015).
- Higher baseline pain scores predicted poorer response (HR: 0.67, 95% CI: 0.45–0.92, p = 0.038).
Sensory complications occurred in 35% of patients (hypesthesia/dysesthesia), but no corneal hypoesthesia or anesthesia dolorosa.
Conclusion: SRS for pure venous conflict in TGN provides durable pain relief (BNI I-II: 70%), though outcomes remain inferior to arterial compression cases due to chronic neuropathic changes. While 35% of patients experienced sensory complications, no major morbidities were observed. SRS outcomes for venous conflict (BNI I-II: 60–70%) are comparable to MVD, suggesting treatment selection should be guided by comorbidities, procedural risks, and individualized goals. Further studies should refine SRS dosing and optimize patient selection in venous-mediated TGN.