The Importance of Clinical Classification in Analysing Cost-effectiveness of Microvascular Decompression and Percutaneous Radio-frequency Rhizotomy for Trigeminal Neuralgia

Introduction: Microvascular decompression (MVD) and percutaneous radio-frequency rhizotomy (PRR) are two of the mainstay surgical treatments for refractory trigeminal neuralgia (TN). Currently, there is limited and conflicting evidence on their cost-effectiveness, with none investigating the role of clinical classification, a well-proven predictor of favorable outcomes. Here, we aim to investigate the importance of TN clinical classification in the cost-effectiveness of MVD and PRR for TN.

Methods: A prospective cohort study was conducted (2017-2020). Baseline characteristics, Burchiel classification, outcome (pain-free survival), and costs (pre-operative, operative, and complication-related) were documented. Quality-adjusted life year (QALY) was calculated from Kaplan-Meier pain-free survival area under the curve (AUC), followed by cost-effectiveness and incremental cost-effectiveness ratio (ICER) analysis according to the clinical classification. The ICER/QALY of less than one times the gross-domestic-product (GDP) per-capita defined cost-effectiveness threshold.

Results: One-hundred and fourteen patients were included in the study; 72 (63.2%) and 42 (36.8%) underwent MVD and PRR, respectively. 71.9% were classified as TN type 1, characterized by a significantly shorter duration from onset to surgery (t-test p< 0.05) and a higher pre-surgical numeric rating scale (χ2 p< 0.05). The mean overall costs of MVD (IDR153,662,266.93) were significantly higher compared to PRR (IDR77,562,742.29, t-test p< 0.05). Without considering the clinical classification, MVD (IDR55,863,274.33/QALY) was more cost-effective than PRR (IDR62,357,711.31/QALY). The costs/QALY for both procedures were lower in type 1 TN (IDR46,509,611.33 for MVD, IDR39,903,028.85 for PRR) compared with other types (IDR268,919,229.22 for MVD, IDR269,940,564.25 for PRR). For type 1 patients, the ICER/QALY for MVD compared to PRR was less than one times GDP/capita (IDR55,288,913.10), which is lower compared to its ICER/QALY among others (IDR267,633,953.68; 4.47 times GDP/capita).

Conclusion : Although the absolute cost of MVD is higher than PRR, it has lower costs/QALY for TN in general. When considering ICER/QALY gain compared to PRR, MVD is only cost-effective in type 1 TN patients.