FM JANUARY 2019 - digital edition

CT
MRI
informs Dr A Anbarasu, a consultant
radiologist and imaging specialist from
Coimbatore, Tamil Nadu and the author
of Oxford Handbook of Head and Neck
Imaging - an introduction to the theory
and practice of head and neck radiology.
Ultrasound has its limitations in
poorly echogenic patients or organs.
Such difficult-to-visualize lesion can
be rendered visible by Smart Fusion,
a technique that combines imaging
modalities. Smart Navigation, a needle
tracking technology, allows for oblique
needle paths and real-time monitoring at
the patient’s bedside without exposing
him or her to ionizing radiation. Both
Smart Fusion and Smart Navigation are
more accessible and less expensive than
a procedure performed under CT or MRI
guidance. This modality is especially
useful in interventional radiology settings.
PET/MR imaging can be beneficial to
improve early and differential diagnosis
of Alzheimer’s disease, studies show.
Through combining the metabolic and
molecular information from PET, and the
structural and functional information
from MR imaging, PET/MR imaging is
considered to have the potential to
broaden diagnostic power. With new
emerging PET radiotracers and MR
imaging techniques, it could become
a conventional first-line one-stop-shop
clinical imaging tool to improve the
current understanding of AD
neuroimaging such as amyloid PET screening for Alzheimer’s
disease etc..
PET-MRI scanners are also being tested on an
experimental basis in the clinical setting. PET/MRIs lead to
lower radiation exposure compared to a PET-CT. PET-MRIs,
however, come with a much higher price tag than PET/CTs.
Some studies show that PET/MRI scans of the brain can
detect abnormal findings that PET/CT misses in more than
50% of patients scanned.
MRI: Defining pathology
Magnetic resonance imaging (MRI) can detect diseases and
pathological tissue. The superior soft tissue contrast in this
cutting-edge imaging modality allows better definition of the
pathology.
MRI is also increasingly used for guiding, monitoring
and controlling percutaneous procedures and surgery. It is
billed a as faster and more accurate method of imaging.
More demanding interventional radiology procedures utilize
the MRI approach.
Magnetic resonance angiography (MRA), an MRI technique
which specifically looks at blood vessels, has been used to
image cerebral and renal arteries and other vessels in the
head and neck, the aorta and its branches, etc.
Recent MRI allows scans of the lungs. Traditionally, MR
imaging has not been possible in the lung since the lungs
are filled with air and there is a low density of the hydrogen
atoms required to create MR images. Now, Ultrashort Echo
Time (UTE) sequence for dedicated pulmonary MRI has been
introduced for clinicians to view high susceptibility regions of
the lung tissue where signals generally disappear too quickly.
The simultaneous multi-slice application software enables
acquisition of MR images simultaneously as opposed to
sequentially. With the use of the new software, physicians
can bring down the length of MRI brain examinations
considerably, which usually vary significantly.
Similarly, cardiac MRI has been made simple with the
introduction of new technology. The new MRI software helps
JANUARY 2019 / FUTURE MEDICINE / 23