HIGH-FIELD MAGNETIC RESONANCE IMAGING IN TRIGEMINAL NEURALGIA CAUSED BY NEUROVASCULAR CONFLICT (ON TOMOGRAPHS 1.5 TL AND 3 TL UNITS)

High-resolution magnetic resonance imaging (MRI) plays an important part in the diagnostic process of clarification of indications for operating and planning operative treatment tactics in patients with neurovascular conflict. Due to higher strength of field 3 Tl MR units have better signal to noise ratio and better image quality. The aim of the study is to compare imaging quality in 3 Tl and 1.5 Tl MR units in patients with neurovascular conflict. Material and Methods. 25 patients with neurovascular conflict were examined in 3 Tl and 1.5 Tl MR units using 3D-CISS images. Delimitation and acuity of anatomical structures, quality of images of two devices were compared. During surgical treatment (microvascular decompression of trigeminal nerve) was made a comparison of MR-images with operation findings. Results. Images in 3 Tl MR unit had better signal to noise ratio and anatomical resolution, in a greater degree corresponding with intraoperational findings, including better differentiation of small vascular and neural structures, and also small vascular branches. According to the research data obtained in tomograph 3 Tl, higher degree of trigeminal nerve compression in comparison with the data of tomograph 1.5 Tl was revealed in some patients. Conclusion. To estimate the neurovascular conflict in patients with trigeminal neuralgia it is better to perform CISS-visualization in 3 Tl MR units having higher sensitivity and delicacy to determine the degree of trigeminal nerve root compression and the presence of small vessels in nerve compression zone. The data have shown that 1.5 Tl MR units also allow us to identify the major causalgic vessel or their combination which compress trigeminal nerve root.

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