Introduction: High-resolution magnetic resonance imaging (MRI) may be a useful adjunct in identifying trigeminal neuralgia due to vascular compression (TGNVC). To date, however, no study has analyzed the incidence and features of vascular compression against a control cohort. The purpose of this study was to evaluate the reliability and predictive ability of heavily T2-weighted MR sequences for the diagnosis of symptomatic vascular compression and response to operative intervention in patients suffering TGNVC.
Methods: We performed a blinded, case-matched control trial evaluating heavily T2-weighted MR sequences in consecutive patients suffering unilateral TGNVC with operatively proven vascular compression of the trigeminal nerve against healthy controls matched on age, sex, and laterality of the pathologic neurovascular complex. Inter-rater reliability was compared between 2 blinded, expert reviewers. Predictive ability of MR was assessed apropos of accuracy, discrimination, and clinical utility.
Results: Forty-four consecutive patients met criteria; mean age was 63±11 years. Inter-rater reliability ranged from fair to excellent for vessel compression (? 0.40), location (0.81), type (0.72), and multiplicity (0.31). Vascular compression on MR sequences did not differ significantly between cases and controls (75 vs. 82%, p= 0.30); neither did location, type, and number of compressive vessels. Notably, MR did demonstrate accurate (Brier 0.18) and good discriminatory ability for clinical response following MVD (AUC 0.81, 95% CI 0.6-1.0). Decision-curve analysis demonstrated a net reduction of 7 cases per 100 evaluated with MR above a decision threshold of 50%.
Conclusions: The results of this study refute recent literature supporting the use of high resolution MR for TGNVC diagnosis. Instead, the utility of heavily T2-weighted MR may lie in stratifying the likelihood of response in those with characteristic symptomatology.
Patient Care: Improve the evaluation and stratification of patients most likely to respond to operative intervention for TGN due to vascular compression.
Learning Objectives: Listeners should be able to apply heavily T2-weighted to the evaluation and stratification of patients most likely to respond to operative intervention in those with characteristic symptomatology of TGN due to vascular compression.