Abstract: Objective：To build the radio-frequency thermocoagulation (RFT) interface under navigation including foramen ovale and trigeminal ganglion based on CT/MRI image fusion technology, to visualize the relationship between the trigeminal ganglion and the puncture needle, and to observe clinical effects of this method. Methods: CT and MRI data of 20 trigeminal neuralgia patients which were input into BrainLAB-iPlan navigation planning system, were aligned and merged, so that the 3-dimentional image fusion interface of CT and MRI for puncture was built. According to the image fusion interface, the pathways targeting the trigeminal ganglion were planned to assist trigeminal ganglion puncture and RFT. The treatment consequences were observed and compared with 20 patients under the RFT only with the direction of pre- and intra-operative CT. Results: In the group of CT/MRI image fusion cases, 3 cases had been predicted to be difficult because of unreachable ganglion through the foramen ovale pathway. The postoperative clinical examination proved that the ganglions of these 3 cases were only insufficiently damaged or undamaged. The other 17 cases proved better results, except 2 cases whose treatment was changed in operation. The valid rates for both image fusion navigation group and CT group were all above 95%. Conclusion:Navigation interface including both foramen ovale and trigeminal ganglion based on CT/MRI image fusion made visualization of the pathway targeting ganglion come true, which made the treatment more accurate and individual. Whether the pathway could reach the ganglion might distinguish the trouble cases from others.

Key words: Trigeminal neuralgia, Electrocoagulation, Surgery, computer-assisted, Tomography, X-ray computed, Magnetic resonance imaging