1、Practical Interpretation of Knee MRI,Routine MRI protocol,Sagittal,Coronal,Axial Spin echo(SE) FSE,STIR T1, T2, PD,JST,Coronal: T2FFE T2 STIR Saggital: T1 T2 T2FFE T2 STIR,TR和TE決定成像加權(quán),短TE 長(zhǎng)TE 短TR T1 無(wú)用途 長(zhǎng)TR PD T2,T1 weighted image (TR1000msec,TE40msec) “anatomy”,T2 weighted image (TR1500msec,TE60mse

2、c) “pathology”,Fat suppression Chemical saturation Short tau inversion recovery (STIR),Tissue characterization,T1 T2 Adipose tissue Fat white gray Yellow marrow Water dark white Cortical bone black black Cartilage gray gray Tendon / ligament/meniscus black/gray black/gray Muscle gray gray Hematoma w

3、hite white Chronic hemorrhage dark dark,Anterior Cruciate Ligament,extension ER 15 20,Normal MR appearance,direct sign of torn ACL,discontinuity,abnornal orientation (fallen ACL),nonvisualization,Avulsion fx,Indirect,Bone bruise sign Deep sulcus sign Segond fx generalized increase in signal intensit

4、y thickness increase Anterior drawer sign Acute hemarthrosis Buckling of PCL,pivot-shift pattern,Kissing sign,Segond sign,Deep sulcus sign, 2mm,generalized increase in signal intensity thickness increase,Buckling of PCL,nonspecific,Ant.drawer sign,Associated soft tissue injuries,Posterior horn of me

5、dial meniscus Bucket handle tear MCL,Posterior Cruciate Ligament,Normal MR appearance,Meniscus-Femoral ligament,Primary sign of PCL,complete tear partial tear “peel off ” injury,Complete tear,Grade1,Grade3,Grade2,partial tear,Secondary sign of PCL injury,bone marrow edema(BME) avulsion fx,Dashboard

6、injury sign,Bone Marrow Edema,Tibial avulsion fx,Associated ligament injury,ACL injury MCL injury PLC/LCL injury,Collateral ligament,Normal Anatomy of MCL,Grading MCL Injuries,Grade 1 (sprain),Grade 2 (partial tear),Grade 3 (complete tear),Normal Anatomy of the LCL Complex/ Posterolateral Corner Com

7、plex,Iliotibial band,LCL,Popliteal plex,Biceps tendon,Visible disruption of one of the posterolateral capsule structures Extensive surrounding soft tissue edema Avulsion fracture or marrow edema involving the medial aspect of the fibular head,Signs of Posterolateral Corner Injury,Menisci,bow ties 2,

8、triangular,rectangular,Criterial to detect meniscal tear,grade 3 signal abnormal meniscal morphology displaced or missing meniscal tissue meniscocapsular separation,Grade III meniscus tear,missing fragment,Displaced fragment,small PHMM,MRI signs,absent bow ties sign(1 or fewer) double PCL sign large

9、 anterior horn sign too many bow ties(3 or more) notch sign,Large & degeneration ant.horn,3 or more bow-ties,Bucket handle tear,double PCL sign,discoid meniscus,3 or more bow-ties,Pitfalls in meniscus diagnosis,Grade II signal Transverse meniscus lig. Popliteal hiatus Meniscofemoral lig. Bursa or fa

10、t plane of MCL,Popliteal hiatus,內(nèi)側(cè)半月板后角的上隱窩 垂直 光滑 不連通,Postoperative Meniscus, Grade 3 signal on T1-weighted images only is indeterminate for tear: it may represent postoperative change or retear of the meniscus Grade 3 signal on a T1-weighted image that is bright as fluid on a T2-weighted image is diagnostic of retear. A displaced meniscal fragment is diagnostic of retear. Grade 3 signal in new a location is diagnostic of retear,Bone Marrow Edema(BME),pivot-shift injury dashboard injury hyperextension injury: ”kissing sign” clip injury patellar dislocation,clip injury,patellar dislo