<s>
Cranial	B-Algorithm
ultrasound	I-Algorithm
is	O
a	O
technique	O
for	O
scanning	O
the	O
brain	O
using	O
high-frequency	O
sound	O
waves	O
.	O
</s>
<s>
A	O
different	O
form	O
of	O
ultrasound-based	O
brain	O
scanning	O
,	O
transcranial	O
Doppler	B-Algorithm
,	O
can	O
be	O
used	O
in	O
any	O
age	O
group	O
.	O
</s>
<s>
This	O
uses	O
Doppler	B-Algorithm
ultrasound	I-Algorithm
to	O
assess	O
blood	O
flow	O
through	O
the	O
major	O
arteries	O
in	O
the	O
brain	O
,	O
and	O
can	O
scan	O
through	O
bone	O
.	O
</s>
<s>
It	O
is	O
not	O
usual	O
for	O
this	O
technique	O
to	O
be	O
referred	O
to	O
simply	O
as	O
"	O
cranial	B-Algorithm
ultrasound	I-Algorithm
"	O
.	O
</s>
<s>
Additionally	O
,	O
cranial	B-Algorithm
ultrasound	I-Algorithm
can	O
be	O
used	O
for	O
intra-operative	O
imaging	O
in	O
adults	O
undergoing	O
neurosurgery	O
once	O
the	O
skull	O
has	O
been	O
opened	O
,	O
for	O
example	O
to	O
help	O
identify	O
the	O
margins	O
of	O
a	O
tumour	O
.	O
</s>
<s>
One	O
of	O
the	O
main	O
purposes	O
of	O
routine	O
cranial	B-Algorithm
ultrasound	I-Algorithm
scanning	O
in	O
neonatal	O
units	O
is	O
to	O
identify	O
these	O
problems	O
as	O
they	O
develop	O
.	O
</s>
<s>
Most	O
neonatal	O
units	O
in	O
the	O
developed	O
world	O
routinely	O
perform	O
serial	O
cranial	B-Algorithm
ultrasound	I-Algorithm
scans	O
on	O
babies	O
who	O
are	O
born	O
significantly	O
premature	O
.	O
</s>
<s>
A	O
water-based	O
gel	O
is	O
applied	O
to	O
the	O
infant	O
's	O
head	O
,	O
over	O
the	O
anterior	O
fontanelle	O
,	O
to	O
aid	O
conduction	O
of	O
ultrasound	B-Application
waves	O
.	O
</s>
<s>
The	O
operator	O
then	O
uses	O
an	O
ultrasound	B-Application
probe	O
to	O
examine	O
the	O
baby	O
's	O
brain	O
,	O
viewing	O
the	O
images	O
on	O
a	O
computer	O
screen	O
and	O
recording	O
them	O
as	O
necessary	O
.	O
</s>
<s>
A	O
standard	O
cranial	B-Algorithm
ultrasound	I-Algorithm
examination	O
usually	O
involves	O
recording	O
of	O
approximately	O
11	O
views	O
of	O
the	O
brain	O
from	O
different	O
angles	O
,	O
six	O
in	O
the	O
coronal	O
plane	O
and	O
five	O
in	O
the	O
sagittal	O
and	O
parasaggital	O
planes	O
.	O
</s>
<s>
In	O
many	O
hospitals	O
in	O
the	O
United	O
Kingdom	O
paediatricians	O
or	O
neonatologists	O
usually	O
perform	O
cranial	B-Algorithm
ultrasound	I-Algorithm
;	O
in	O
other	O
systems	O
advanced	O
nurse	O
practitioners	O
,	O
radiologists	O
or	O
sonographers	O
may	O
perform	O
most	O
scans	O
.	O
</s>
<s>
While	O
the	O
anterior	O
fontanelle	O
is	O
the	O
most	O
commonly	O
used	O
acoustic	O
window	O
for	O
cranial	B-Algorithm
ultrasounds	I-Algorithm
,	O
more	O
advanced	O
operators	O
may	O
gain	O
additional	O
views	O
,	O
especially	O
of	O
posterior	O
fossa	O
structures	O
,	O
by	O
using	O
the	O
mastoid	O
fontanelle	O
,	O
the	O
posterior	O
fontanelle	O
and/or	O
the	O
temporal	O
window	O
.	O
</s>
<s>
Other	O
refinements	O
of	O
cranial	B-Algorithm
ultrasound	I-Algorithm
technique	O
include	O
serial	O
measurement	O
of	O
the	O
width	O
of	O
the	O
lateral	O
ventricles	O
(	O
"	O
ventricular	O
index	O
"	O
)	O
to	O
monitor	O
suspected	O
ventricular	O
dilatation	O
and	O
colour	O
Doppler	B-Algorithm
to	O
assess	O
blood	O
flow	O
.	O
</s>
<s>
Cranial	B-Algorithm
ultrasound	I-Algorithm
is	O
a	O
very	O
safe	O
technique	O
as	O
it	O
is	O
non-invasive	O
and	O
does	O
not	O
involve	O
any	O
kind	O
of	O
ionising	O
radiation	O
.	O
</s>
<s>
Operator	O
dependency	O
:	O
the	O
quality	O
of	O
images	O
obtained	O
relies	O
on	O
the	O
skill	O
of	O
the	O
person	O
performing	O
sonography	B-Application
.	O
</s>
<s>
Therefore	O
,	O
many	O
neonatal	O
services	O
prefer	O
to	O
perform	O
an	O
MRI	B-Algorithm
scan	O
when	O
the	O
infant	O
is	O
near	O
term	O
,	O
as	O
well	O
as	O
routine	O
cranial	B-Algorithm
ultrasound	I-Algorithm
,	O
to	O
avoid	O
missing	O
more	O
subtle	O
abnormalities	O
.	O
</s>
