The Comparison Of 1.5T MR Multiple Sequences Imaging In Metacarpophalangeal Joint Cartilage

Objective:To explore different scan sequences and parameters imaging in metacarpophalangeal joint cartilage, Through the comparison of SNR and CNR, to evaluate capability and superiority of clinical MRI sequences in hand joint cartilage.Methods:The first right metacarpophalangeal joints were imaged in coronal plane with Siemens 1.5T unit. The sequences include:FSE T1WI,FSE T2WI,FSPDWI,3D-FLASH and WE 3D-FLASH。All data were measured in the middle layer through double-blind method by two radiologists. The signal intensity (SI) of the cartilage and other tissue. Then the cartilage SNR and CNR between cartilage and bone cortex, cartilage and bone marrow, cartilage and normal sodium were calculated.Results:1. Comparison of the three different flip angle(FA10°,FA20°,FA30°) 3D-FLASH sequences:The cartilage SNR and the CNR of cartilage-bone cortex and cartilage-normal sodium were significantly higher than other flip angle.3D-FLASH (FA20°) are better than other 3D-FLASH which the flip angle is 10°or 30°in hand cartilage imaging.2. Comparison of the three different flip angle(FA10°,FA20°,FA30°)WE 3D-FLASH sequences:The cartilage SNR and the CNR of cartilage-bone cortex were significantly higher than other flip angle. And its CNR of cartilage-marrow and cartilage-normal sodium were also in a high level. WE 3D-FLASH (FA20°) are better than other WE 3D-FLASH which the flip angle is 10°or 30°in hand cartilage imaging.3. Comparison of the whole five sequences:The cartilage SNR and the CNR of cartilage-bone cortex of 3D-FLASH and WE 3D-FLASH were significantly higher than other sequences. The CNR of cartilage-marrow of WE 3D-FLASH was significantly higher than other three sequen-ces, whereas not different significantly from FSE T1WI. The CNR of cartilage-normal sodium of FSE T2WI was highest in all five sequences.Conclusions:3D-FLASH (FA20°) and WE 3D-FLASH (FA20 °) have significant advantages compared with other clinical sequences in hand joint imaging. WE 3D-FLASH have some advantages in bone marrow imaging.