Jumat, 22 Mei 2009

How to Get Good Image in MRI

Problem solving abaut images in MRI

CONTRAST CHANGE (Black and White )
T2W image (TR 2000-7000 ms) (TE 60-150ms)
Muscle is too dark, reduce TE 60-80ms side effect high signal to noise
CSF not bright, increase TE 100-120ms, increase TR 3000-5000ms side effec scan time may longer

T1W image (TR 400-700ms) (TE less than 20ms)
CSF not dark. so reduce TR ( should be in the range )

FAT SUPPRESSION
Too dark
STIR technique, change TI delay 170-220ms or more
SPIR technique change frequency offset (maybe trial and error 20-30 or more) it is below SPIR
SPAIR technique 1.Check T1 delay = 1/3 of SPAIR TR
2.Change frequency offset (maybe trial and error 20-30 or more)

How to adjust TR
1.User defind, enter number (2000-7000ms side effect scan time increase
2.adjust minimum number of package in geometry page scan time slightly increase.

Tidak ada komentar:

Poskan Komentar