<s>
Ultrasound	B-Algorithm
transmission	I-Algorithm
tomography	I-Algorithm
(	O
UTT	O
)	O
is	O
a	O
form	O
of	O
tomography	B-Algorithm
involving	O
ultrasound	B-Application
.	O
</s>
<s>
Like	O
X-ray	O
tomography	B-Algorithm
,	O
the	O
attenuation	O
of	O
the	O
ultrasound	B-Application
as	O
it	O
passes	O
through	O
the	O
object	O
can	O
be	O
measured	O
,	O
but	O
since	O
the	O
speed	O
of	O
sound	O
is	O
so	O
much	O
lower	O
than	O
the	O
speed	O
of	O
light	O
,	O
the	O
delay	O
as	O
it	O
passes	O
through	O
the	O
object	O
can	O
also	O
be	O
measured	O
,	O
allowing	O
estimation	O
of	O
both	O
the	O
attenuation	O
coefficient	O
and	O
the	O
index	O
of	O
refraction	O
.	O
</s>
<s>
Traditional	O
ultrasound	B-Application
imaging	I-Application
primarily	O
detects	O
boundaries	O
between	O
different	O
media	O
.	O
</s>
