495: Percutaneous Glycerol Rhizotomy for Trigeminal Neuralgia: A Prospective Observational Cohort Study.

Topic: Clinical Science
Subtopic: Pain category (ICD-11), Chronic primary orofacial pain, Pharmacological treatments

Background and Aims: In low‑ and middle‑income countries, there is limited access to theatre and critical cere services which constrains the use of surgical microvascular decompression for medically refractory trigeminal neuralgia (TN). Percutaneous glycerol rhizotomy (PGR) is a minimally invasive day‑case alternative. In this multicentre prospective observational cohort study, we undertook to prospectively assess pain, functionality and medication use before and after PGR in adults with medically refractory TN.

Methods: A prospective multicentre observational cohort study was conducted at three South African hospitals. Thirty adults underwent PGR with a tailored 0.3–0.4 mL glycerol instillation delivered into the trigeminal cistern. Outcomes included Brief Pain Inventory‑Short Form (BPI‑SF, 0–10), Penn Facial Pain Scale‑Revised (Penn‑FPS‑R), Patient Global Impression of Change (PGIC), and medication use which were measured pre‑op, in recovery (<24 h), and at 3 months. The primary outcome was worst pain change at 3 months.

Results: On the BPI‑SF 0–10 numeric rating scale, within hours of PGR the median decreases were: worst pain 5.5 points; average 5.5; current 5.5; least 4.5. At 3 months, the median decreases were: worst 7.0; average 6.0; current 6.0; least 4.5 (all p<0.0001). Penn‑FPS‑R declined (indicates improvement) from 32.1% to 6.7% and 29/30 (97%) patients improved. On PGIC, 17/30 (56.7%) were “very much improved.” By 3 months, 11/30 (37.0%) were medication‑free; 5/30 (16.7%) halved carbamazepine; 14/30 (46.7%) were unchanged.

Conclusions: The PGR procedure produced rapid, substantial and sustained analgesia, reduced functional interference by 60%, and enabled over 36% of patients to discontinue medication within 90 days. Outcomes mirror higher‑resource series, supporting PGR as an efficient, scalable intervention for medically refractory TN in LMIC health systems.

References: 1. Yadav Y, Nishtha Y, Sonjjay P, Vijay P, Shailendra R, Yatin K. Trigeminal neuralgia. Asian Journal of Neurosurgery. 2017;12(04):585-597. doi:10.4103/ajns.AJNS_67_14
2. Khawaja SN, Scrivani SJ. Trigeminal Neuralgia. Dent Clin North Am. Jan 2023;67(1):99-115. doi:10.1016/j.cden.2022.07.008
3. Love S, Coakham HB. Trigeminal neuralgia: pathology and pathogenesis. Brain. Dec 2001;124(Pt 12):2347-60. doi:10.1093/brain/124.12.2347
4. Devor M, Govrin-Lippmann R, Rappaport ZH. Mechanism of trigeminal neuralgia: an ultrastructural analysis of trigeminal root specimens obtained during microvascular decompression surgery. J Neurosurg. Mar 2002;96(3):532-43. doi:10.3171/jns.2002.96.3.0532
5. Bendtsen L, Zakrzewska JM, Abbott J, et al. European Academy of Neurology guideline on trigeminal neuralgia. Eur J Neurol. Jun 2019;26(6):831-849. doi:10.1111/ene.13950
6. Zakrzewska JM, Linskey ME. Trigeminal neuralgia. Bmj. Mar 12 2015;350:h1238. doi:10.1136/bmj.h1238
7. Chang KW, Jung HH, Chang JW. Percutaneous Procedures for Trigeminal Neuralgia. J Korean Neurosurg Soc. Sep 2022;65(5):622-632. doi:10.3340/jkns.2022.0074
8. Sindou M, Leston J, Decullier E, Chapuis F. Microvascular decompression for primary trigeminal neuralgia: long-term effectiveness and prognostic factors in a series of 362 consecutive patients with clear-cut neurovascular conflicts who underwent pure decompression. J Neurosurg. Dec 2007;107(6):1144-53. doi:10.3171/jns-07/12/1144
9. Rughani AI, Dumont TM, Lin CT, Tranmer BI, Horgan MA. Safety of microvascular decompression for trigeminal neuralgia in the elderly. Clinical article. J Neurosurg. Aug 2011;115(2):202-9. doi:10.3171/2011.4.Jns101924
10. Nair SK, Xie ME, Kalluri A, et al. The influence of prior percutaneous rhizotomy on outcomes following microvascular decompression for trigeminal neuralgia. J Neurosurg. Apr 1 2024;140(4):1155-1159. doi:10.3171/2023.8.Jns231345
11. Farrar JT, Young JP, Jr., LaMoreaux L, Werth JL, Poole MR. Clinical importance of changes in chronic pain intensity measured on an 11-point numerical pain rating scale. Pain. Nov 2001;94(2):149-158. doi:10.1016/s0304-3959(01)00349-9
12. Cleeland CS, Ryan KM. Pain assessment: global use of the Brief Pain Inventory. Ann Acad Med Singap. Mar 1994;23(2):129-38.
13. Symonds T, Randall JA, Hoffman DL, Zakrzewska JM, Gehringer W, Lee JY. Measuring the impact of trigeminal neuralgia pain: the Penn Facial Pain Scale-Revised. J Pain Res. 2018;11:1067-1073. doi:10.2147/jpr.S152958
14. Pollock BE. Percutaneous retrogasserian glycerol rhizotomy for patients with idiopathic trigeminal neuralgia: a prospective analysis of factors related to pain relief. J Neurosurg. Feb 2005;102(2):223-8. doi:10.3171/jns.2005.102.2.0223
15. Slettebø H, Hirschberg H, Lindegaard KF. Long-term results after percutaneous retrogasserian glycerol rhizotomy in patients with trigeminal neuralgia. Acta Neurochir (Wien). 1993;122(3-4):231-5. doi:10.1007/bf01405534
16. Kouzounias K, Lind G, Schechtmann G, Winter J, Linderoth B. Comparison of percutaneous balloon compression and glycerol rhizotomy for the treatment of trigeminal neuralgia. J Neurosurg. Sep 2010;113(3):486-92. doi:10.3171/2010.1.Jns091106
17. Asplund P, Blomstedt P, Bergenheim AT. Percutaneous Balloon Compression vs Percutaneous Retrogasserian Glycerol Rhizotomy for the Primary Treatment of Trigeminal Neuralgia. Neurosurgery. Mar 2016;78(3):421-8; discussion 428. doi:10.1227/neu.0000000000001059
18. Wu FHW, Cheung CW, Leung YY. Neuronavigation-guided Percutaneous Rhizotomies to Trigeminal Neuralgia: A Systematic Review. Clin J Pain. Apr 1 2024;40(4):253-266. doi:10.1097/ajp.0000000000001191
19. Lopez BC, Hamlyn PJ, Zakrzewska JM. Systematic review of ablative neurosurgical techniques for the treatment of trigeminal neuralgia. Neurosurgery. Apr 2004;54(4):973-82; discussion 982-3. doi:10.1227/01.neu.0000114867.98896.f0
20. Hajikarimloo B, Mohammadzadeh I, Tos SM, et al. Stereotactic radiosurgery for tumor-related trigeminal neuralgia: a systematic review and meta-analysis. BMC Neurol. May 3 2025;25(1):195. doi:10.1186/s12883-025-04204-6

Presenting Author: Amina Kajee
Submitting Author: Amina Kajee

Senior Author: Amina Kajee

IASP 2026 Global Year theme of Neuropathic Pain: Yes

• Amina Kajee: MB CHB DA (SA) - Discipline of Anaesthesiology, Pain medicine and Critical care, School of Clinical Medicine, College of Health Sciences, University of KwaZulu-Natal, Durban, KwaZulu-Natal, South Africa
• Rohan Harrichandparsad: MbChB, FCA (SA) Neuro, MMed - Department of Neurosurgery, Inkosi Albert Luthuli Central Hospital, Durban, KwaZulu-Natal, South Africa
• David Le Feuvree: MBChB, FCS (SA)(Neuro), MMed - Division of Neurosurgery, Department of Surgery, Groote Schuur Hospital, Cape Town, Western Cape, South Africa
• Allan Taylore: MBChB, FCS (SA) (Neuro), MMed, MSc - Division of Neurosurgery, Department of Surgery, Faculty of Health Sciences, University of Cape Town, South Africa

Speakers

View More Speakers...