<s>
Hyperpolarized	B-Algorithm
gas	I-Algorithm
MRI	I-Algorithm
,	O
also	O
known	O
as	O
hyperpolarized	O
helium-3	O
MRI	O
or	O
HPHe-3	O
MRI	O
,	O
is	O
a	O
medical	B-Application
imaging	I-Application
technique	I-Application
that	O
uses	O
hyperpolarized	O
gases	O
to	O
improve	O
the	O
sensitivity	O
and	O
spatial	O
resolution	O
of	O
magnetic	O
resonance	O
imaging	O
(	O
MRI	O
)	O
.	O
</s>
<s>
The	O
basic	O
principle	O
of	O
hyperpolarized	B-Algorithm
gas	I-Algorithm
MRI	I-Algorithm
is	O
similar	O
to	O
that	O
of	O
conventional	O
MRI	O
,	O
which	O
uses	O
powerful	O
magnetic	O
fields	O
and	O
radio	O
waves	O
to	O
create	O
detailed	O
images	O
of	O
the	O
body	O
's	O
internal	O
structures	O
.	O
</s>
<s>
3He	O
also	O
does	O
not	O
have	O
any	O
physiological	O
side	O
effects	O
,	O
making	O
it	O
a	O
better	O
starting	O
point	O
for	O
clinical	B-Application
imaging	I-Application
.	O
</s>
<s>
Xenon	O
has	O
a	O
long	O
history	O
of	O
safe	O
use	O
as	O
a	O
contrast	O
agent	O
in	O
computed	O
tomography	O
lung	O
imaging	B-Application
studies	I-Application
,	O
which	O
was	O
confirmed	O
in	O
safety	O
studies	O
on	O
inhaling	O
hyperpolarized	O
129Xe	O
.	O
</s>
<s>
The	O
basic	O
principle	O
of	O
hyperpolarized	B-Algorithm
gas	I-Algorithm
MRI	I-Algorithm
is	O
similar	O
to	O
that	O
of	O
conventional	O
MRI	O
,	O
which	O
uses	O
powerful	O
magnetic	O
fields	O
and	O
radio	O
waves	O
to	O
create	O
detailed	O
images	O
of	O
the	O
body	O
's	O
internal	O
structures	O
.	O
</s>
<s>
In	O
hyperpolarized	B-Algorithm
gas	I-Algorithm
MRI	I-Algorithm
,	O
the	O
gases	O
used	O
are	O
noble	O
gases	O
,	O
such	O
as	O
3He	O
or	O
129Xe	O
,	O
which	O
have	O
large	O
nuclear	O
magnetic	O
moments	O
but	O
low	O
natural	O
abundance	O
and	O
therefore	O
produce	O
very	O
weak	O
signals	O
.	O
</s>
<s>
Hyperpolarized	B-Algorithm
gas	I-Algorithm
MRI	I-Algorithm
is	O
a	O
technique	O
that	O
uses	O
the	O
alignment	O
of	O
nuclear	O
spins	O
in	O
certain	O
gases	O
,	O
such	O
as	O
3He	O
or	O
129Xe	O
,	O
to	O
create	O
detailed	O
images	O
of	O
the	O
body	O
's	O
internal	O
structures	O
.	O
</s>
