Objective To evaluate the three-dimensional contrast-enhanced MR venography in assessment of the lower extremityveins.Methods 15 patients with lower extremity veins thrombosis confirmed by operation,DSA or ultrasonic were undergone directthree-dimensional contrast-enhanced MR venography using GE Signa 1.0T MR system.The demonstration of the lower extremity veins wasobserved.Results 3D deep or superficial vein images of low abdomen,pelvis and low extremity were acquired satisfactorily in all 15patients.Conclusion Direct three-dimensional contrast-enhanced MR venography is a favorable method in accessing lower extremity veins.

Objective To investigate the MRI feature of fatigue fracture. Methods MRI of 11 cases of fatigue fracture was retrospectively analyzed and was confirmed by pathology and clinical diagnosis. Results The fracture line,swelling of marrow cavity and soft tissue were well demonstrated using MRI,especially T 2WI STIR images.Conclusion MRI is of great value in the early diagnosing of fatigue fracture for early treatment.

Objective To characterize the CT and MRI features of Osgood-Schlatter disease (OSD),and explore the feasibility of staging OSD by using CT and MRI.Methods The imaging data of the 27 cases with OSD were retrospectively analyzed,and fea-tures of MRI and CT were characterized.Results All 27 cases with OSD were featured with different extent of edema within the pa-tellar tendon.The portion already exhibited edema in the secondary ossification center in 5 cases,which showed high signal intensity on the T2 WI.There were 1 5 cases which exhibited ossified or tears in the secondary ossification center,and 5 of them were featured with opened shell-like separation on sagittal radiograph.Seven cases had isolated solitary ossicles located at the lower part of the pa-tellar ligament,which is also thickening.Among the 7 cases,one showed hypertrophy in the tibial tuberosity.Three cases examined with CT scan,exhibited ossified nodules located at the lower part of the patellar ligament.Conclusion OSD has characteristic CT and MRI features,and MRI scan is an important imaging method to show edema and morphological changes of patellar tendon in OSD,which could help to identify the stage of OSD and predict the prognosis.