<s>
Sialography	B-Algorithm
(	O
also	O
termed	O
radiosialography	O
)	O
is	O
the	O
radiographic	O
examination	O
of	O
the	O
salivary	O
glands	O
.	O
</s>
<s>
It	O
usually	O
involves	O
the	O
injection	O
of	O
a	O
small	O
amount	O
of	O
contrast	B-Application
medium	I-Application
into	O
the	O
salivary	O
duct	O
of	O
a	O
single	O
gland	O
,	O
followed	O
by	O
routine	O
X-ray	B-Library
projections	O
.	O
</s>
<s>
The	O
resulting	O
image	O
is	O
called	O
a	O
sialogram	B-Algorithm
.	O
</s>
<s>
Sialography	B-Algorithm
has	O
largely	O
been	O
replaced	O
by	O
sialoendoscopy	O
and	O
cross-sectional	O
imaging	O
,	O
such	O
as	O
CT	O
,	O
MRI	B-Algorithm
and	O
ultrasonography	O
.	O
</s>
<s>
However	O
,	O
for	O
those	O
who	O
are	O
pregnant	O
,	O
with	O
allergy	O
to	O
iodinated	B-Algorithm
contrast	I-Algorithm
,	O
and	O
ongoing	O
infection	O
or	O
inflammation	O
of	O
the	O
face	O
,	O
the	O
procedure	O
is	O
contraindicated	O
.	O
</s>
<s>
A	O
baseline	O
radiograph	O
(	O
scout	O
film	O
)	O
of	O
the	O
required	O
salivary	O
gland	O
would	O
be	O
taken	O
,	O
the	O
duct	O
is	O
dilated	O
using	O
graded	O
lacrimal	O
probes	O
,	O
a	O
cannula	O
then	O
is	O
inserted	O
in	O
this	O
salivary	O
gland	O
duct	O
's	O
opening	O
in	O
the	O
mouth	O
,	O
then	O
a	O
radio-opaque	O
fluid	O
(	O
contrast	B-Application
medium	I-Application
)	O
is	O
injected	O
in	O
the	O
duct	O
through	O
a	O
small	O
tube	O
.	O
</s>
<s>
There	O
is	O
also	O
irregular	O
salivary	O
duct	O
stricture	O
(	O
narrowing	O
)	O
of	O
the	O
duct	O
,	O
which	O
creates	O
an	O
appearance	O
known	O
as	O
"	O
sausage	O
link	O
"	O
pattern	O
on	O
a	O
sialogram	B-Algorithm
.	O
</s>
<s>
Sialadenitis	O
is	O
inflammation	O
of	O
the	O
salivary	O
glands	O
,	O
which	O
may	O
cause	O
acinar	O
atrophy	O
and	O
create	O
an	O
appearance	O
known	O
as	O
"	O
pruning	O
of	O
the	O
tree	O
"	O
on	O
a	O
sialogram	B-Algorithm
,	O
where	O
there	O
are	O
less	O
branches	O
visible	O
from	O
the	O
duct	O
system	O
.	O
</s>
<s>
This	O
may	O
create	O
an	O
appearance	O
known	O
as	O
"	O
ball	O
in	O
hand	O
"	O
on	O
an	O
sialogram	B-Algorithm
,	O
where	O
the	O
ducts	O
are	O
curved	O
around	O
the	O
mass	O
of	O
the	O
lesion	O
.	O
</s>
<s>
Allergic	O
reaction	O
to	O
iodinated	B-Algorithm
contrast	I-Algorithm
media	I-Algorithm
(	O
which	O
may	O
present	O
with	O
urticaria	O
,	O
dyspnoea	O
,	O
and	O
hypotension	O
)	O
.	O
</s>
