الفهرس 
CEREBRAL HEMISPHERESOnly 14 pages are availabe for public view
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Abstract
1.5T scanners have been the optimal standard imaging platform
for a long time and with the continuous improvements in the
hardware and software, it has been even tougher to compete with.
The introduction of 3T scanners has been promising from the
very beginning with the concept being simple doubling of the SNR.
3T scanning has also greatly enhanced spatial and temporal
resolution compared to older MRI technology.
In the real life though, 3T platform had suffered from major
restrictions early on; with increasing SAR and consequently heat
deposition, dielectric effect, changes of the tissue relaxation time,
and artifacts due to field inhomogenicity. The overall efficacy was
not satisfactory and had restricted its usage to being only a research
tool. But it was known from the very beginning it beholds a high
potential that needs to be refined in order to expose its maximum
benefits and capabilities.
That had changed with the ongoing improvements and various
solutions for each of the high field platform problems. The
introduction of PAT and the new coils design and sensitivity played
a pivotal role in introducing the 3T scanners into the everyday-use
and imposed it as a strong rival for the old 1.5T platform,
superseding it in nearly all aspects allowing faster imaging, higher
resolution or a bit of both. Indeed If not valuable in itself its
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Summary & Conclusion
allowance to use parallel imaging, which can be done only in high
field platforms, make the 3T scanners worth using.
The 3T platform has been extensively used in the
Neuroimaging and the Brain was considered as the main beneficiary
of the high field platform although 3T has proved to be very
efficient in other organs. The main organs to be benefited are; the
prostate, the breast, abdominal and pelvic imaging, cardiac imaging
and musculoskeletal imaging.
There is no Neuroimaging imaging technique, the 3T platform
cannot handle and produce better results or at least equal results to
that of the 1.5T platform in even shorter time for example;
* Anatomical imaging: It is true that the anatomical details
showed in 3T is unparalleled compared to 1.5T, which help greatly
in the detection of MS, Neurodegenerative diseases and the
volumetric studies of the hippocampus important in diagnosis of
mesial temporal sclerosis.
* Angiography: Indeed it is considered that neurovascular
imaging is one exam that should always be conducted at 3T. It had
exploited the advantage of more tissue suppression surrounding the
blood vessels due to reduction in T1 relaxation time and the nearly
non affection of the T1 and T2* of the blood signal found in 3T
imaging. In addition a low dose of contrast (0.05 mmol Gd instead.