Investigating The Application Of 3D-SPGR Sequence In The Delayed Gadolinium-Enhanced MRI Of Cartilage.

Objective:一,To investigate the application of 3D-SPGR sequence in diagonosing osteoarthritisof human knee joint using the delayed gadolinium-enhanced MRI of cartilagetechnique.二, To investigate the enhancement characteristic of the articular capsule in knee jointafter indirect MR arthrography and select the optimal time of follow-up whileperforming non-traumatic arthrography.Materials and Methods:30 subjects, 17 male, 13 female, age range: 25-68, mean age: 40.2 years. 17 of the subjects was asymptomatic volunteers, 12 male, S female, age range: 25-68, mean age: 36.8 years. The other 13 subjects were suffered from knee pain of various degree lasted from 2 months to 7 years, 5 male, 8 female, age range: 26-64years, mean age: 44.8 years. 8 cases met the diagnostic criteria for osteoarthritis clinically. All subjects undergoing MR imaging scan were without injection, immediately after I.V. injection, 2hours after I.V. and 4hours after I.V. injection with 0.2mmol/kg body weight of gadolinium. Subjects were asked to walk for at least 10 min to facilitate the transport of the charged gadolinium agent into the cartilage during the intermission. The sequence involved in this research was 3D-SPGR sequence (TR/TE: 38/6.9, flip angle:45°, FOV:16×16, matrix: 256×224, 3-mm section thickness, no gap). Regions of interest(ROIs) selected on sagittal images that displayed the largest amount of cartilage were the anterior third and middle third of the medial and lateral femoral condylar cartilage. 30 subjects included 120 ROIs. Of all the 68 normal ROIs, 15 were excluded because of the scan position, while the other 53 ROIs were included in this research by outlining the contour of the normal articular cartilage, measuring the signal intensity and caculating their ratio to the SI of the popliteal fossa. 52 ROIs of the symptomatic patient were recorded, among them there were 23 lesions, 11 lesions of the 5 patients were confirmed by arthroscopy. Measuring the IS of the lesions by using oval ROIs, meantime, measuring the corresponding adjacent normal cartilage...