<s>
A-scan	B-Algorithm
ultrasound	I-Algorithm
biometry	I-Algorithm
,	O
commonly	O
referred	O
to	O
as	O
an	O
A-scan	B-Algorithm
(	O
short	O
for	O
Amplitude	O
scan	O
)	O
,	O
is	O
a	O
routine	O
type	O
of	O
diagnostic	O
test	O
used	O
in	O
optometry	O
or	O
ophthalmology	O
.	O
</s>
<s>
The	O
A-scan	B-Algorithm
provides	O
data	O
on	O
the	O
length	O
of	O
the	O
eye	O
,	O
which	O
is	O
a	O
major	O
determinant	O
in	O
common	O
sight	O
disorders	O
.	O
</s>
<s>
The	O
most	O
common	O
use	O
of	O
the	O
A-scan	B-Algorithm
is	O
to	O
determine	O
eye	O
length	O
for	O
calculation	O
of	O
intraocular	O
lens	O
power	O
.	O
</s>
<s>
By	O
measuring	O
both	O
the	O
length	O
of	O
the	O
eye	O
(	O
A-scan	B-Algorithm
)	O
and	O
the	O
power	O
of	O
the	O
cornea	O
(	O
keratometry	O
)	O
,	O
a	O
simple	O
formula	O
can	O
be	O
used	O
to	O
calculate	O
the	O
power	O
of	O
the	O
intraocular	O
lens	O
needed	O
.	O
</s>
<s>
The	O
other	O
major	O
use	O
of	O
the	O
A-scan	B-Algorithm
is	O
to	O
determine	O
the	O
size	O
and	O
ultrasound	O
characteristics	O
of	O
masses	O
in	O
the	O
eye	O
,	O
in	O
order	O
to	O
determine	O
the	O
type	O
of	O
mass	O
.	O
</s>
<s>
This	O
is	O
often	O
termed	O
quantitative	O
A-scan	B-Algorithm
.	O
</s>
