The Value Of MRTA In The Etiological Diagnosis Of Trigeminal Neuralgia

[Objective]To explore the value of MR tomographic angiography (MRTA) in the etiological diagnosis of trigeminal neuralgia(TN).[Metheds]Forty-five patients with TN and 20 healthy controls underwent MRTA. The relationship of the fifth cranial nerve to adjacent vessels was best visualized on the three-dimensional time-of-flight magnetic resonance angiography (3D-TOF MRA)and constructive interference at steady state (CISS-MR) sequences. The results from MRTA were compared with the outcome of MVD.[Results]Neurovascular contact/compress(NVC) was identified in 41 of 45 symptomatic sides, in 9 of 45 opposite sides and 10 of 40 control sides.The positive rate of NVC in symptomatic sides were significant higher than that in the opposite sides and the control group(p<0.05), no significant difference was found between the opposite sides and the control group(P>0.05).Evaluating the MRTA diagnosis on NVC: the sensitivity rate is 93.75 % the specificity rate is 81.82 % the accuracy rate is 88.89%the positive predictive value is 88.24%the negative predictive value is 90%the positive likelihood ratio is 5.16the negative likelihood ratio is 0.077Youden S index is 0.76.[Conclusions]MRTA demonstrates that neurovascular contact/compress at the root entry zones in cases of TN. These findings were verified at surgury.The specificity and accuracy in diagnosis of NVC by MRTA are high.MRTA can show the anatomical relationship accurately which is beneficial for clinic treatment.