Evaluating The Application Value Of 3D-SPACE And DTI For Anterior Cruciate Ligament

Objective: To investigate the value of 3D-SPACE and DTI used for describing the normal AC L anatomical structure;And further to analyze its value of the diagnosis of an ACL injury.Materials and methods: 1.General informations:Select 20 cases of normal anterior cruciate ligament of knee joint;Collect 10 cases of anterior cruciate ligament injury,after surgery or arthroscopy confirmed for anterior cruciate ligament tear completely.2.MR equipment and technology(1)scanning equipment:use Siemens 3.0 T magnetic resonance imaging system and eight channel knee joint surface coil,supine enough inspectors using advanced,the center of the coil placed in the bottom of patella.(2)scan sequence : conventional MRI sequences(fat suppression T2 WI horizontal axis,fat suppression PDWI coronal and sagittal),3D-SPAC E,DTI imaging sequences.(3)the image post-processing:use 3D-SPAC E image to reconstruct oblique coronal,oblique sagittal and oblique axial.Evaluate effect of reconstruction image that display length of AC L : class I: ligament length can be observed on a picture;Class II: over two consecutive images can be observed;Level III: in the three or more of the image can be observed the ligament length,or length cannot be observed.Evaluate the anteromedial bundle(AMB)and posterlateral bundle(PLB): evaluation in the same picture can be detected on the ACL on the tibia end,middle segment and the femur end;Rate the outline of two bundle: three points,clear demarcate the contour of two bundle,;two points,contour of two bundle fuzzy;one point,cannot distinguish contour of two bundle.make fiber tracer(FT)imaging to Normal ACL.measure FA and ADC values of normal ACL femoral upper,middle and the bottom of the tibia;measure FA and ADC value in ACL injured part,Corresponding to the same area measurement ADC value and FA value of normal ACL.3.Observational indexes(1)3D-SPACE image of the normal ACL;(2)performance of normal ACL in DTI images;(3)the value of 3D-SAPCE reconstruction to the diagnosis of injury of ACL;(4)performance of ACL injury in DTI and FT images;(5)3D-SAPCE and DTI diagnosis injury of ACL.4.Statistical analysis(1)the effect of Different ways of 3D-SPACE reconstruction and conventional MRI display Total length and double-bundle of the normal ACL,using two independent sample rank inspection;(2)comparing the FA and ADC values of different parts of normal ACL,using the diverse mean variance analysis;(3)comparing diagnostic value of different reconstruction methods of 3D-SPACE for an ACL injury,using the single factor analysis of variance;(4)Comparing FA and ADC value of injury and normal ACL,using two independent sample mean t test.Results: 1.3D-SPACE imaging of normal ACL and compare with conventional magnetic resonance imaging :(1)AMB and PLB of 20 cases normal AC L in oblique coronal is triangular;In the oblique sagittal plane respectively show AMB and PLB of the ACL;doublebundle of ACL in Oblique axis plane,on the femoral side are closely linked,in the middle section of the double-bundle cross section similar to round,tibial attachment area two double-bundle present inverted U.(2)3D-SPACE and conventional MRI in 20 cases of normal AC L anatomical structure comparison: The length of the ACL in 3D-SPACE in 20 cases(100%)are shown as class I;On conventional MRI in 11 cases(55%)are shown as class I,9 cases(45%)showed as class II.3D-SPACE for normal ACL display effect is superior to conventionalMRI,both have significant difference(P=0.014).The ACL tibia side,middle segment and the femur shows two bundle on the distribution of 3D-SAPCE for ACL display effect is superior to conventional MRI,significant differences between the two(P =0.000).2.DTI image of the normal ACL : 6 cases of DTI images are eliminated by artifact heavier image analysis in 20 cases of normal ACL,14 cases of image quality is good.(1)normal AC L anatomical location map: AC L outline clear,go straight;Color figure: FA AC L levels owe evenly,give priority to with green and blue order;ADC images: AC L area signal comparing around the muscle is slightly low signal;FT image: can't distinguish the AC L function of respective fiber line,but the ACL whole fiber bundle rules,walk the line continuation;Pseudo color display fiber orientation.(2)the mean FA value of 14 cases of normal AC L on the femoral side,middle section,the tibia are: 0.202 ±0.017?0.171±0.009?0.147±0.018,from top to bottom the FA values gradually reduce,the difference was statistica lly significant(P =0.000);And ADC values are: 2.094±0.460?2.199±0.415?2.283±0.287,the differences of average ADC values was no statistical significance(P =0.540).3.3D-SPACE reconstruction imaging of ACL injury : 10 cases completely torn ACL in oblique coronal and sagittal were unable to show on the total length of the ACL.the continuous line of ACL on oblique position break.4.DTI image of ACL injury : 10 cases of ACL injury on the anatomical localization image: ACL lines of discontinuity,higher signal;ADC images: AC L feature display is not clear;Color FA images: ACL area signal color confusion;FT image: ACL fiber bundle go line interruption,end enlargement of fiber bundles,irregular structure.5.3D-SPACE and DTI for the diagnosis of an ACL injury(1)oblique sagittal and coronal and oblique position of 10 patients with ACL completely torn all can make a definite diagnosis,the diagnosis of various reconstruction methods have no statistical difference(P > 0.05).(2)average FA value of an AC L injury is 0.091 ±0.014,corresponding to average FA value of normal AC L 0.186±0.018,injury FA values are much smaller than normal group(P =0.000);An AC L injury group average ADC values was 2.328±0.136,corresponding to normal ACL average ADC values is2.042±0.169,the ADC values of injury group than the normal group is higher,the difference was statistically significant(P =0.003).Conclusion: 1.3D-SAPCE is conducive to normal ACL structure,the DTI can be used in the quantitative evaluation of the ACL;2.3D-SPACE can effectively show the ACL tear morphology change completely;3.DTI is conducive to objective evaluation of AC L injury,the FA value reduce ACL injury than the same Part of normal ACL,and ADC values increase,can provide useful information for an ACL injury diagnosis;fiber tracer technology helps show an ACL injury the space form of change;4.the 3D-SPACE and DTI is advantageous to the comprehensively evaluate the ACL injury from the form and objective quantitative parameters.