The Study Of Diffusion Tensor Imaging And Dual Source Computed Tomography On Anterior Cruciate Ligament Injury Classification And Grafts After Reconstuction

Part ? The Correlation between Anterior Cruciate Ligament Injury Classification and Diffusion Tensor Imaging with Dual Source Computed TomographyObjectiveTo analyze the correlation among fractional anisotropy(FA)?apparent diffusion coefficient(ADC)and computed tomography housfield unit with the injury grade of anterior cruciate ligament(ACL)utilizing diffusion tensor imgaing(DTI)and dual source computed tomography(DSCT).To explore the feasibility and value of quantitative assessment of anterior cruciate ligament injury grade on DTI and DSCT.Diffusion tensor tractography(DTT)and dual source tendon model reconstruction are also utilizing to display the morphological changes of anterior cruciate ligament.MethodsSubject:35 patients doubted with ACL injury clinically and diagnosis injury by arthroscopy were performed,whose medical history was all over 3 months,age 18-45.20 cases normal anterior cruciate ligament were also selected into the research,the collimation is 20×0.6mm,the pitch is 0.7mm,the thickness is 0.75mm,the reconstruction increment is 0.5mm,and the field of vision(FOV)is 250mm.Scanning parameters,image manipulation,data measurement:MR scanning was performed by Siemens 3.0T Verio.Using sagittal T1-weighted images?T2-weighted images.PD-FS and axial PD-FS and coronal PD-FS.The sagittal DTI was performed using echo planar imaging(EPI)with 400s/mm2 b-value and 20 different diffusion sensitivity gradient directions,which location is consistent with the normal sagittal position.CT scanning was performed by Siemens Definition FLASH,which tube voltages were 140kV and 80kV,4Dcase automatic tube current regulation technology.Dual energy staining was performed under the dual energy mode of tendon and ligament module,and three dimensional reconstruction of CT includes multi planar reconstruction(MPR),volume rendering technique(VRT)and curved planar reformation(CPR).Scanning range is up to the edge of femoral condyle,down to the tibial and fibular head.The original MR data obtained by scanning is transmitted to the Siemens workstation,and the data was processed by the workstation software,which generate color coded FA diagram,ADC diagram.The region of interest(ROI)was recorded on the anterior cruciate ligament anatomy and FA fusion images along the anterior cruciate ligament injury.ROI,placed in three levels adjacent,area was choosen 20-25mm,and to record every level of FA and ADC values,which were measured three times and got the average.Scanning with dual energy mode of tendon and ligament module,the CT values of ROIs were measured three times and got the average for statistics.Statistical method:All the data were analyzed with SPSS 19.0 statistical package.The normal anterior cruciate ligament was defined as grade 0 damage.FA,ADC and CT values of different grades of anterior cruciate ligament injury were compared by one-way analysis of variance,if the variance was not homogeneous,compared by approximate Welch method to correct.As a post hoc test,if homogeneous,the variance was analyzed by LSD,if not,by Dunnett-T3 test.The test level was =0.05,P<0.05 was statistically significant.Evaluating the diagnostic value of anterior cruciate ligament injury,the sensitive and specif icty of FA,ADC and CT values and the united index included FA combined CT values?ADC combined CT values?FA combined ADC values,were compared by drawing the receiver operating characteristic(ROC)curve.Results1.The FA values,ADC values and CT values showed significant difference among injury degree(P=0.000,P=0.000,P=0.000).Further comparison between 2 groups,for FA values,expect for grade ? and ?,there were significant difference between other injury grades.For ADC values,except for grade ?and?,???,there were significant difference between other injury grades.For CT values,except for grade 0? ???? ??? ??,there were significant difference between other injury grades.2.There is certain correlation between anterior cruciate ligament damage degree and the FA value,ADC values,CT value.The greater the damage degree,the lower the value of FA and CT value,and ADC values is higher,which reflects the more severe anterior cruciate ligament injury.The strongest correlation is FA value,which is an important parameter reflecting the anterior cruciate ligament damage.3.DTT can directly display the morphology of anterior cruciate ligament,normal anterior cruciate ligament fiber bundle is complete and continuous,mainly blue fiber bundle,and anterior cruciate ligament with different degrees of injury showed different degrees of interruption,disorders,even partial blue fiber bundle was significantly reduced or disappeared,where mixed with different proportions red and green mixed fiber bundles.4.Dual energy mode of tendon and ligament reconstruction of anterior cruciate ligament showed normal ligament were natural,continuous,normal morphology,uniform color,full of dual energy staining.Anterior cruciate ligament injury showed different degrees of morphological thickening,and dual energy staining showed different degrees of color reduced or disappeared.Conclusion1.With the injury grades of anterior cruciate ligament increased,the lower the FA value,the higher the ADC value,the lower the CT value.DTI,DSCT can detect the anterior cruciate ligament microstructure changes at the molecular level.FA value,ADC value and CT value can quantitatively assess the grades of ACL injury.The FA value is the highest diagnostic value.The anterior cruciate ligament diffusion tensor imaging and dual source CT can detect the microstructural changes in the molecular level.2.The pattern of DTT and dual energy mode of tendon and ligament can intuitively show the morphology of the normal and different grades damaged ACL,which can be used to comprehend the ligament injury.Part ? Diffusion Tensor Imaging and Dual Source Computed Tomography imaging on the Anterior Cruiate Ligament Grafts after ReconstructionObjectiveUsing DTI and dual source CT imaging,the preoperative and postoperative FA,ADC,CT values of ACL grafts were analyzed.Moreover,to analyze the changes of FA,ADC,CT values of reconstruction of tendon grafts in different periods,which were compared with normal ACL.It is help to comprehend the remodeling process of ACL grafts.MethodsSubject:The patients grade ?(10 patients),grade ?(13 patients)injury comfirmed by arthroscope and normal volunteers(20 person)were enrolled.The patients received MR and CT scans in the 3th months and the 6th months after ACL graft reconstruction.Scanning parameters,image manipulation,data measurement:The same to Part ?.Statistical method:The FA,ADC and CT value of ACL gtaft before reconstruction and after reconstruction were compared with Paired T test.The? and ? grade injury as a postoperative group compared with normal group,the FA,ADC,CT value of normal and postoperative group reconstructed after 3 months and 6 months,were compared with independent T test.The test level was =0.05,P<0.05 was statistically significant.Results1.Comparison of FA,ADC and CT values of before and after ACL reconstruction in patients with grade ? and ? injury.The FA values showed significant difference between reconstruction after 3 months,6 months and preoperative ACL in grade ? and ? injury.It also showed significant difference between reconstruction after 3 months and after 6 months in ?injury,but not for ? injury.The ADC values showed significant difference in each periods comparison in both grade ? and ? injury.CT values showed significant difference between reconstruction after 3 months,6 months and preoperative ACL in grade ? and ? injury,but not for reconstruction after 3 months and 6 months.2.The comparison of the normal group and the reconstruction group of FA,ADC and CT value.For FA value,there was significant difference between the group of normal and 3 months after operation,and there was no significant difference between the the group of normal and 6 months after operation.For ADC value,there was significant difference between the normal and 3 months,6 months after operation group.For CT value,there was no significant difference between the group of normal and 3 months,6 months after operation.3.In DTT,the ACL grafts were demonstrated as normal,regular shape,mainly blue fiber bundle.The ACL grafts after 3 months and 6 months reconstruction have no significant difference with the normal ACL in DTT.4.Dual energy mode of tendon and ligament reconstruction showed ACL grafts were natural,continuous,normal morphology,uniform color,full of dual energy staining.Anterior cruciate ligament injury showed different degrees of morphological thickening.The ACL grafts after 3 months and 6 months reconstruction have no significant difference with the normal ACL in dual energy mode of tendon and ligament.Conclusion1.The reconstruction of ACL grafts,with the time after the operation,the higher the FA value,the lower the ADC value,the lower the CT value.DTI,DSCT can detect the ACL grafts microstructure changes at the molecular level and the process of ACL graft to "ligament".FA,ADC and CT value can quantitatively evaluate the degree of graft tissue rehabilitate.2.The arrangement of the fibers in the 6 months after ACL reconstruction was similar to that of normal ligament.In the 6 months after transplantation,the ACL grafts were not yet fully mature,but there was no obvious edema and exudation.3.Diffusion tensor tractography can show the reconstruction after 3 months and 6 months of tendon graft shape and form,can directly display the tendon graft after reconstruction of repair plant.DSCT can display dyeing and content of hydroxylysine and hydroxyproline content of collagen molecules in graft after 3 months and 6 months reconstruction.