Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:2.7.11.8 (FAST)
 758 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

In the steady-state free precession (SSFP) with an applied linear gradient, the transverse magnetizations are periodically distributed. Fourier analysis of this periodic distribution leads to the understanding of many interesting phenomena in SSFP. It is found that there are many other higher-order echoes in SSFP in addition to the previously known echoes. By deriving general description of the transverse magnetization of SSFP and by expanding the echo time independent term with Fourier series, the higher-order echoes including the two previously known FISP and CE-FAST are understood and explained. These higher-order echoes are studied in detail by both computer simulation and experiments and their results are reported.
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PMID:Analysis of the higher-order echoes in SSFP. 204 35

Optimal angle, fast repeat time, gradient field echo imaging techniques such as FISP (Fast Imaging with Steady Precession) and FLASH (Fast Low Angle Shot) often fail to discriminate disease from healthy tissue for two main reasons. First, T1 and T2 of the affected tissue may increase such that the ratio of T1 to T2 remains nearly unchanged, hence there is no contrast change with FISP. Second, T2 weighted gradient field echo images suffer severely from T2* signal and resolution loss leading to a reduction in C/N. Although FLASH imaging with two separate angles can, in principle, extract the longer T1 tumors, contrast is often not good. To overcome the inhomogeneity and contrast problems, we have implemented a FAst optimal angle spin-echo sequence with a short TE(FATE). For the first echo, FATE has the same contrast properties as FLASH with a slight decrease in signal intensity. The advantage is that the intensity of the signal does not suffer from T2* signal decay, hence improved contrast and disease detection via T2 weighted FATE images is possible. Contrast-to-noise in lesion detection is also considered for CE FAST (Contrast Enhanced Fast), a T2-weighted version of FISP, and HYBRID.
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PMID:A comparison of fast spin echo and gradient field echo sequences. 318 31

Imaging techniques of PSIF/CE-FAST (fast gradient echo) and TSE (turbo spin echo) are described. PSIF/CE-FAST is a mirror imaged FISP (fast imaging with steady state precession) technique which is applied to MR cholangiopancreatography (MRCP) for the first time. However, it has been replaced by TSE technique because of poor resolution and motion artifacts. TSE is a fast imaging technique using multiecho method, which enables us to obtain high resolution MRCP with heavily T2-weighted images. MRCP using TSE shows high signal to noise ratio with minimal motion artifacts. Recently, breath-hold single shot fast imaging techniques within a few seconds or respiratory triggered TSE are applied to MRCP and shows higher resolution for pancreatobiliary ducts system.
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PMID:[PSIF/CE-FAST (fast gradient echo) and TSE (turbo spin echo)]. 984 97