MRI Study Of Detecting The Offending Vessels In Primary Trigeminal Neuralgia Patients

Objectives:1.To investigate the best combination of MRI sequences for detecting offending veins in patients with primary trigeminal neuralgia(PTN).2.To investigatethe correlations between topography of pain and site of the neurovascular conflict(NVC)in PTN patients.To find a more accurate way to detect the offending vessels and to provide PTN patients more dependable advice for clinical treatment prescription.Methods:123 patients with unilateral PTN were retrospectively studied on3D-TOF-MRA sequence,3D-FIESTA sequence,and CE-3D-TOF-MRA sequence.1.The displaying rate and imaging features of the 33 offending veins of the 26(26/123)PTN patients by venous compression alone were analyzed.2.NVC sites were divided into 8 sites according to the sectional anatomy of trigeminal nerve.60(60/123)patients were with a single offending vessel and a single site of NVC.The correlations between their topography of pain and site of NVC were analyzed combined with the morphology of the trigeminal nerve.3.123 patients existed 206 NVC points.Measure the distance(d)from the site of NVC to the root entry point,the length(L)of cisternal segment of the trgeminal nerve.Calculate d/L.Results 1.Of the 33 offending veins,100%(33/33)was revealed on CE-3D-TOF-MRA sequence,63.6%(21/33)was revealed on 3D-FIESTA sequence alone or 3D-FIESTA sequence combined with 3D-TOF-MRA sequence,15.2%(5/33)was revealed on 3D-TOF-MRA sequence.CE-3D-TOF-MRA sequence had a significant higher detection rate than that of 3D-TOF-MRA sequence(?2=45.220,P<0 005),than that of 3D-FIESTA sequence or combined with 3D-TOF-MRA sequence(?2=12.324,P<0.005).2.Of the 60 patients,95.0%(57/60)sites of the NVC matched to topography of pain,and 5.0%(3/60)did not match.3.Of the 206 NVC points,the mean"d" was 2.5mm,and d/L<1/4:44.7%(92/206),d/L?1/2:74.3%(153/206).Of the 60 patients,d/L?1/4:58.3%(35/60),d/L?1/2:85.0%(51/60).Conclusions 1.CE-3D-TOF-MRA sequene has the highest rate for detecting offending veins.Combining 3D-TOF-MRA?3D-FIESTA and CE-3D-TOF-MRA sequences can confirm whether the offending vessel is an artery or a vein,and show more details of the NVC,which can reduce the probability of missing offending vein.2.Analyzing the correlations between topography of pain and site of NVC and measuring the distance from the site of NVC to the root entry point will provide MRI a more accurate diagnosing method for detecting the offending vessels in PTN patients,provide more significative information for the patients' treatment prescription.