Magnetic resonance diffusion tensor imaging of trigeminal nerve in healthy volunteers

Abstract

Objective To survey the apparent diffusion coefficient (ADC) value and fractional anisotropy (FA) value ofpontine cistern section of the trigeminal nerve, and understand the characteristics of various parameters of trigeminal nerve pontine cistern section. Methods The distances from pontine cistern section of the trifacial nerve to 0, 3, 6 and 9 mm of brain stem in 50 healthy volunteers were recorded, and fusion images of magnetic resonance diffusion tensor imaging (DTI) with B-TFE or THRIVE were achieved to improve the spatial resolution of the pontine cistern section of the trifacial nerve; their ADC value and FA value were recorded, separately. Tracing image formation was noted in the pontine cistern section of the trigeminal or trifacial nerve. Results The ADC and FA results of the left side and right flank of pontine cistern section of the trifacial nerve in these healthy volunteers were not statistically different (P＜0.05). The closer to the brain stem, the more asymmetrical tendency of distance from pontine cistern section of the trifacial nerve to 0, 3, 6 and 9 mm of brain stem between both sides. DTI indicated that the ADC values between each 2 distances from pontine cistern section of the trifacial nerve to 0, 3, 6 and 9 mum of brain stem between both sides were significantly different: the ADC values increased along with the distance elevating gradually, but rotated suddenly at the line of 6-9 mm. The FA value increased in 0-6 mm along with the distance reducing gradually, and the neighboring 2 distances had remarkably statistical difference, but the FA value no longer obviously changed from the line of 6-9 mm. Conclusion DTI can distinguish the two-sided trigeminal nerve brain pond section clearly, and may realize each item of DTI. Regular changes are noted in FA and ADC values along with the different distances from pontine cistern section of the trifacial nerve to 0, 3, 6 and 9 mm of brain stem,indicating that DTI enjoys perspective in being clear about the discrimination of cranial nerve CNS section, the change-over portion and the PNS section, and in detecting the cranial nerve vascular compression. Key words: Diffusion tensor imaging; Apparent diffusion coefficient; Fractional Anisotrop