Abstract:Objective: To retrospectively analyze the morphology factors of trigeminal nerve in 95 patients with idiopathic trigeminal neuralgia (ITN), and to explore its correlation with pain degree and the prognosis of percutaneous radiofrequency thermocoagulation (PRT). Methods: Collected the general data and MRI images of unilateral 95 patients with ITN treated by PRT.We measured and compared MRI morphological factors, including the length and cross-sectional area of trigeminal nerve roots, trigeminal-pontine angle, angle of trigeminal nerve root across petrous apex on both sides, neurovascular relationship,and we calculated the atrophy degree of trigeminal nerve root. Evaluated the correlation between MRI morphology of trigeminal nerve and NRS score. The postoperative efficacy of PRT was obtained through telephone follow-up and divided into recurrence group and non-recurrence group. Univariate and Logistic multivariate regression analysis was used to evaluate the independent risk factors affecting the prognosis of PRT.Results: The trigeminal root cross-sectional area and trigeminal-pontine angle on the symptomatic side of ITN patients were smaller than those on the asymptomatic side (P<0.05) ; trigeminal-pontine angle is negatively correlated with NRS score (r=-0.206, P<0.05);Univariate analysis showed that the course of disease, TR length and atrophy degree were related to the prognosis of PRT (P < 0.1), and logistic regression analysis showed that:the course of disease is an independent risk factor for recurrence after PRT (OR=2.834, P<0.05). Conclusions: The symptomatic side trigeminal nerve atrophy and the small trigeminal-pontine angle have reference value for the diagnosis of ITN; The trigeminal-pontine angle is related to pain degree; The course of disease is an independent risk factor for the prognosis of PRT.