The Study Of Magnetic Resonance Diffusion Tensor Imaging In Patients With Trigeminal Neuralgia

Objective:To study the clinical value of the diffusion tensor imaging (DTI) in healthy volunteers and the patients with trigeminal neuralgia (TN), and provide a reliable scientific basis for diagnosis and accurate preoperative assessment by measuring the apparent diffusion coefficient (ADC) values and fractional anisotropy (FA) values in the healthy control group and groups of the responsibility of vascular compression of the trigeminal nerve cisternal segment.Materials and Methods:1. General information:1.1 Control group:50 normal volunteers (volunteers agreed and signed informed consent form before the test was made) received cisternal trigeminal nerve segment DTI examination.25 cases were male (50%), female 25 cases (50%); aged from 15 to 82 years, mean 51.35 years.1.2. TN lesion group:60 cases of patients with TN confirmed by surgery were collected from March 2009 to February 2010, including 28 males and 32 females; aged from 26 to 84 years, mean 52.40 years.2. Equipment and methods:Scanning equipment:PHILIPS 1.5T MR scanner, SENSE NV 16-channel joint coil.Scanning sequence:Routine axial plane T2WI (TR 4500ms, TE 119ms) and T1WI (TR 480ms, TE 15ms), ultra-fast balanced field echo (Balanced Turbo Field Echo, B-TFE) sequence (TR 5.6ms TE 2.8ms),3D-T2WI (TR 1500ms TE 250ms), T1 high-resolution isotropic volume excitation (T1 high resolution isotropic volume excitation, THRIVE) sequence (TR 5.1ms TE2.2 ms), DTI (TR 11496ms TE 62ms). 3D-TOF (TR 23 ms, TE 5 ms).3. Case group and methods of measurement3.1. Case group:According to the age the healthy volunteers were divided into 3 groups, less than 35,35 to 55, and more than 55 years,and the distance away from the brain stem the brainstem cisternal segment of trigeminal nerve 0mm,3mm, 6mm,9mm 4 groups. In accordance with the B-TFE sequence and intraoperative evaluation of morphological changes of the trigeminal nerve, the patients with vascular compression of trigeminal nerve trigeminal nerve cisternal segment were divided into A, B, C, D 4 group.3.2.Data post processing:All data was measured in the EWS (Extended MR WorkSpace) workstation applications Fibertrack and Diffusion software post-processing. Region of interest (ROI) was circular or point, ADC and FA values were recorded in different groups.4. Results analysis4.1. ADC values and FA values of healthy control group:50 cases were enrolled in different age groups on each side of DTI export volume comparison,understanding of all ages with DTI export volume between the overall if significant differences, the normal brain stem trigeminal nerve issue from different point of distance, and the DTI and the export volume of the overall characteristics and age groups, whether there was statistically significant or not.4.2. The ADC and FA values of patients:The ADC and FA values of patients were measured using Diffusion software in the parts of the trigeminal nerve compression ADC, FA values, and the average value of each parameter was calculated, the control group and the patients, the mean ADC values, FA values between the overall mean, whether there were statistically significances or not. Statistical degree of trigeminal nerve injury in ADC and FA values from the existence of close relationship.5. Statistical indicators, data processing and statistical methodsThe statistical analysis was performed by SPSS 13.0 statistical software. Measurement data with x±s that control different between the trigeminal nerve and the control group and the spread between the TN group parameters among groups using ANOVA, each corresponding to about two TN side of the control group and each TN group and two groups each with Newman-Keuls method; byα=0.05 level, with P<0.05 for the significant, difference statistically. Results:There were no statistical differences in patients and healthy control group's age and sex composition ratio. The ADC value of trigeminal nerve in the healthy volunteers group was (1.76±0.98)×10-3mm2/s, FA value (0.40±0.18).50 cases of examiners appeared closer to the brainstem, making the point on the left and right brain pool section of the trigeminal nerve the export volume, the more rendering around asymmetric, various ages trigeminal brain pool section from the brainstem issued point different distance the export volume, the difference more concentrated in the 55 years of age group to ADC's difference more obvious. ADC adjacent two distance level had a significant statistical difference; FA value between 0-6mm increased with distance, and the distance between two adjacent level, there was a significant statistical difference.In 60 cases of TN, A,B,C,and D group were 17 cases,19 cases,13 cases, and 11 cases respectively. Patient group trigeminal parts ADC, FA values were measured and the average value of each parameter was calculated.In the control group and the group of patients with an average of ADC value (F=32.56, P=0), FA value (F=115.43, P =0) between the number of overall there were statistically differences. There was no difference statistically (P>0.05) in the ADC, FA value of the control group and A group of patients.In the control group and B, C, D three trigeminal nerve compression comparison, ADC, FA value differences were present statistical significance (P <0.01)Conclusion:1. DTI could distinguish the trigeminal nerve cisternal segment, enable the measurement of the export volume.2. The DTI export volume of trigeminal nerve cisternal segment had a close relationship with the change of age.3. As the distance from the brainstem to different levels of issue point of the trigeminal nerve cisternal segment, regular changes of the export volume occurred.4. Vascular oppression in the majority of patients with TN concentrated in the 0-3mm area of the trigeminal nerve cisternal segment.5. In most parts of the trigeminal nerve chronic constriction injury the ADC values increased and had a higher sensitivity,FA values decreased and had a lower sensitivity.6. ADC values, FA values had a close relationship with the severity level of the trigeminal nerve compression.7. DTI could provided a reliable scientific basis for diagnosis in patients with TN.