<s>
Ultrasonography	B-Application
of	O
suspected	O
or	O
previously	O
confirmed	O
chronic	O
venous	O
insufficiency	O
of	O
leg	O
veins	O
is	O
a	O
risk-free	O
,	O
non-invasive	O
procedure	O
.	O
</s>
<s>
As	O
with	O
heart	B-Application
ultrasound	I-Application
(	O
echocardiography	B-Application
)	O
studies	O
,	O
venous	O
ultrasonography	B-Application
requires	O
an	O
understanding	O
of	O
hemodynamics	O
in	O
order	O
to	O
give	O
useful	O
examination	O
reports	O
.	O
</s>
<s>
In	O
chronic	O
venous	O
insufficiency	O
,	O
sonographic	B-Application
examination	O
is	O
of	O
most	O
benefit	O
;	O
in	O
confirming	O
varicose	O
disease	O
,	O
making	O
an	O
assessment	O
of	O
the	O
hemodynamics	O
,	O
and	O
charting	O
the	O
progression	O
of	O
the	O
disease	O
and	O
its	O
response	O
to	O
treatment	O
.	O
</s>
<s>
On	O
ultrasound	B-Application
at	O
the	O
saphenofemoral	O
junction	O
in	O
the	O
groin	O
,	O
the	O
common	O
femoral	O
vein	O
(	O
CFV	O
)	O
with	O
the	O
GSV	O
and	O
the	O
common	O
femoral	O
artery	O
(	O
CFA	O
)	O
create	O
an	O
image	O
called	O
the	O
Mickey	O
Mouse	O
sign	O
.	O
</s>
<s>
The	O
use	O
of	O
ultrasonography	B-Application
in	O
a	O
medical	O
application	O
was	O
first	O
used	O
in	O
the	O
late	O
1940s	O
in	O
the	O
United	O
States	O
.	O
</s>
<s>
The	O
first	O
report	O
on	O
Doppler	B-Algorithm
ultrasound	I-Algorithm
as	O
a	O
diagnostic	O
tool	O
for	O
vascular	O
disease	O
was	O
published	O
in	O
1967	O
–	O
1968	O
.	O
</s>
<s>
Rapid	O
advances	O
since	O
then	O
in	O
electronics	O
,	O
has	O
greatly	O
improved	O
ultrasound	B-Algorithm
transmission	I-Algorithm
tomography	I-Algorithm
.	O
</s>
<s>
Ultrasonography	B-Application
does	O
not	O
involve	O
the	O
use	O
of	O
ionizing	O
radiation	O
,	O
and	O
the	O
procedure	O
is	O
harmless	O
and	O
can	O
be	O
safely	O
used	O
on	O
anybody	O
of	O
any	O
age	O
.	O
</s>
<s>
The	O
ultrasound	B-Application
equipment	O
must	O
be	O
of	O
sufficiently	O
high	O
quality	O
in	O
order	O
to	O
give	O
a	O
correct	O
image	B-Algorithm
processing	I-Algorithm
result	O
,	O
which	O
can	O
then	O
provide	O
invaluable	O
information	O
,	O
mainly	O
at	O
the	O
superficial	O
level	O
.	O
</s>
<s>
It	O
must	O
be	O
able	O
to	O
provide	O
both	O
color	B-Application
and	O
Doppler	B-Algorithm
imaging	O
;	O
technologies	O
that	O
developed	O
alongside	O
the	O
development	O
of	O
ultrasound	B-Application
.	O
</s>
<s>
The	O
use	O
of	O
Doppler	B-Algorithm
measurements	O
which	O
trace	O
the	O
echoes	O
of	O
the	O
generated	O
soundwaves	O
received	O
by	O
the	O
probe	O
,	O
enable	O
the	O
direction	O
and	O
the	O
velocity	O
of	O
the	O
blood	O
flow	O
,	O
to	O
be	O
depicted	O
.	O
</s>
<s>
The	O
overlay	O
of	O
color	B-Application
onto	O
the	O
Doppler	B-Algorithm
information	O
lets	O
these	O
images	O
be	O
seen	O
more	O
clearly	O
.	O
</s>
<s>
In	O
contrast	O
to	O
arterial	O
ultrasonography	B-Application
the	O
wall	O
of	O
the	O
vein	O
is	O
not	O
relevant	O
and	O
importance	O
is	O
given	O
to	O
the	O
hemodynamic	O
conclusions	O
that	O
the	O
examiner	O
can	O
obtain	O
in	O
order	O
to	O
provide	O
a	O
valuable	O
report	O
.	O
</s>
<s>
Specialized	O
training	O
in	O
venous	O
ultrasonography	B-Application
is	O
not	O
undertaken	O
in	O
some	O
countries	O
,	O
which	O
undermines	O
best	O
practice	O
,	O
mainly	O
when	O
varicose	O
veins	O
need	O
to	O
be	O
examined	O
.	O
</s>
<s>
Ultrasonography	B-Application
is	O
based	O
on	O
the	O
principle	O
that	O
sound	O
can	O
pass	O
through	O
human	O
body	O
tissues	O
and	O
is	O
reflected	O
by	O
the	O
tissue	O
interfaces	O
in	O
the	O
same	O
way	O
that	O
light	O
can	O
reflect	O
back	O
on	O
itself	O
,	O
from	O
a	O
mirror	O
.	O
</s>
<s>
Tissue	O
in	O
the	O
body	O
will	O
offer	O
varying	O
degrees	O
of	O
resistance	O
,	O
known	O
as	O
acoustic	O
impedance	O
,	O
to	O
the	O
path	O
of	O
the	O
ultrasound	B-Application
beam	O
.	O
</s>
<s>
When	O
the	O
ultrasound	B-Application
beam	O
meets	O
air	O
,	O
or	O
solid	O
tissue	O
such	O
as	O
bone	O
,	O
their	O
impedance	O
difference	O
is	O
so	O
great	O
that	O
most	O
of	O
the	O
acoustic	O
energy	O
is	O
reflected	O
making	O
it	O
impossible	O
to	O
see	O
any	O
underlying	O
structures	O
.	O
</s>
<s>
The	O
gel	O
prevents	O
air	O
bubbles	O
from	O
forming	O
between	O
the	O
probe	O
,	O
and	O
the	O
patient	O
's	O
skin	O
and	O
so	O
helps	O
the	O
conduction	O
of	O
the	O
sound	O
waves	O
from	O
the	O
transducer	B-Algorithm
into	O
the	O
body	O
.	O
</s>
<s>
The	O
imaging	O
capability	O
needed	O
,	O
was	O
made	O
possible	O
with	O
the	O
developments	O
of	O
Doppler	B-Algorithm
and	O
color	B-Algorithm
Doppler	I-Algorithm
.	O
</s>
<s>
Doppler	B-Algorithm
measurements	O
using	O
Doppler	B-Algorithm
effect	O
can	O
show	O
the	O
direction	O
of	O
the	O
blood	O
flow	O
and	O
its	O
relative	O
velocity	O
and	O
color	B-Algorithm
Doppler	I-Algorithm
is	O
the	O
provision	O
of	O
color	B-Application
to	O
help	O
interpret	O
the	O
image	O
,	O
showing	O
for	O
example	O
,	O
the	O
blood	O
flow	O
towards	O
the	O
probe	O
in	O
one	O
color	B-Application
and	O
that	O
flowing	O
away	O
another	O
.	O
</s>
<s>
The	O
probe	O
is	O
an	O
ultrasonic	B-Algorithm
sensor	I-Algorithm
,	O
generally	O
known	O
as	O
a	O
transducer	B-Algorithm
,	O
which	O
functions	O
to	O
send	O
and	O
receive	O
acoustic	O
energy	O
.	O
</s>
<s>
The	O
reflected	O
ultrasound	B-Application
is	O
received	O
by	O
the	O
probe	O
,	O
transformed	O
into	O
an	O
electric	O
impulse	O
as	O
voltage	O
and	O
sent	O
to	O
the	O
engine	O
for	O
signal	O
processing	O
and	O
conversion	O
to	O
an	O
image	O
on	O
the	O
screen	O
.	O
</s>
<s>
The	O
depth	O
reached	O
by	O
the	O
ultrasound	B-Application
beam	O
is	O
dependent	O
on	O
the	O
frequency	O
of	O
the	O
probe	O
used	O
.	O
</s>
<s>
Unlike	O
the	O
arterial	O
ultrasound	B-Application
study	O
,	O
when	O
the	O
sonographer	O
studies	O
venous	O
insufficiency	O
,	O
the	O
vein	O
wall	O
itself	O
has	O
no	O
relevance	O
and	O
attention	O
will	O
be	O
focused	O
on	O
the	O
direction	O
of	O
blood	O
flow	O
.	O
</s>
<s>
In	O
this	O
way	O
,	O
venous	O
ultrasonography	B-Application
has	O
at	O
times	O
become	O
a	O
hemodynamic	O
examination	O
which	O
is	O
reserved	O
for	O
experienced	O
sonographers	O
who	O
have	O
completed	O
hemodynamic	O
studies	O
and	O
training	O
and	O
have	O
acquired	O
a	O
deep	O
knowledge	O
of	O
this	O
subject	O
.	O
</s>
<s>
Also	O
,	O
unlike	O
ultrasonography	B-Algorithm
of	I-Algorithm
deep	I-Algorithm
venous	I-Algorithm
thrombosis	I-Algorithm
,	O
the	O
procedure	O
focuses	O
mainly	O
on	O
superficial	O
veins	O
.	O
</s>
<s>
Also	O
,	O
unlike	O
the	O
arterial	O
ultrasound	B-Application
examination	O
,	O
blood	O
velocity	O
in	O
veins	O
has	O
no	O
diagnostic	O
meaning	O
.	O
</s>
<s>
This	O
low	O
velocity	O
is	O
responsible	O
for	O
the	O
fact	O
that	O
it	O
can	O
only	O
be	O
detected	O
spontaneously	O
with	O
the	O
Doppler	B-Algorithm
effect	O
on	O
the	O
proximal	O
and	O
larger	O
femoral	O
and	O
iliac	O
veins	O
.	O
</s>
<s>
Venous	O
ultrasonography	B-Application
of	O
the	O
lower	O
limbs	O
is	O
the	O
most	O
demanding	O
of	O
the	O
medical	O
complementary	O
examinations	O
.	O
</s>
<s>
This	O
compartmentalization	O
is	O
useful	O
in	O
an	O
ultrasonographic	B-Application
examination	O
because	O
it	O
makes	O
systematization	O
,	O
mapping	O
execution	O
,	O
and	O
any	O
surgery	O
strategic	O
,	O
easier	O
.	O
</s>
<s>
The	O
sapheno-femoral	O
junction	O
is	O
tested	O
by	O
the	O
Valsalva	O
maneuver	O
with	O
the	O
use	O
of	O
color	B-Algorithm
Doppler	I-Algorithm
being	O
helpful	O
at	O
this	O
stage	O
.	O
</s>
<s>
The	O
use	O
of	O
ultrasonography	B-Application
has	O
allowed	O
a	O
number	O
of	O
variations	O
to	O
be	O
shown	O
at	O
this	O
level	O
;	O
when	O
no	O
contact	O
is	O
made	O
with	O
the	O
popliteal	O
vein	O
it	O
might	O
be	O
seen	O
to	O
drain	O
in	O
the	O
GSV	O
,	O
at	O
a	O
variable	O
level	O
;	O
or	O
,	O
it	O
may	O
merge	O
with	O
the	O
Giacomini	O
vein	O
and	O
drain	O
in	O
the	O
GSV	O
at	O
the	O
superior	O
1/3	O
of	O
the	O
thigh	O
.	O
</s>
<s>
The	O
ultrasonography	B-Application
report	O
will	O
include	O
insufficient	O
and	O
continent	O
perforators	O
,	O
which	O
will	O
also	O
be	O
shown	O
on	O
venous	O
mapping	O
.	O
</s>
<s>
The	O
Doppler	B-Algorithm
effect	O
was	O
first	O
described	O
by	O
Christian	O
Doppler	B-Algorithm
in	O
1843	O
.	O
</s>
<s>
Both	O
of	O
these	O
findings	O
were	O
used	O
in	O
the	O
development	O
of	O
ultrasonography	B-Application
.	O
</s>
<s>
The	O
first	O
ultrasound	B-Application
was	O
applied	O
to	O
the	O
human	O
body	O
for	O
medical	O
purposes	O
by	O
Dr.George	O
Ludwig	O
,	O
University	O
of	O
Pennsylvania	O
,	O
in	O
the	O
late	O
1940s	O
.	O
</s>
<s>
The	O
use	O
of	O
ultrasonography	B-Application
in	O
medicine	O
soon	O
followed	O
in	O
different	O
locations	O
around	O
the	O
world	O
.	O
</s>
<s>
In	O
the	O
mid-1950s	O
more	O
research	O
was	O
undertaken	O
by	O
Professor	O
Ian	O
Donald	O
et	O
al.	O
,	O
in	O
Glasgow	O
,	O
which	O
advanced	O
the	O
practical	O
technology	O
and	O
applications	O
of	O
ultrasound	B-Application
.	O
</s>
<s>
In	O
1963	O
,	O
in	O
France	O
,	O
Léandre	O
Pourcelot	O
started	O
on	O
his	O
thesis	O
,	O
which	O
was	O
presented	O
in	O
1964	O
,	O
and	O
used	O
pulsed	O
Doppler	B-Algorithm
for	O
blood	O
flow	O
calculation	O
as	O
its	O
subject	O
.	O
</s>
<s>
Dr.	O
Gene	O
Strandness	O
and	O
the	O
bio-engineering	O
group	O
at	O
the	O
University	O
of	O
Washington	O
who	O
conducted	O
research	O
on	O
Doppler	B-Algorithm
ultrasound	I-Algorithm
as	O
a	O
diagnostic	O
tool	O
for	O
vascular	O
disease	O
,	O
published	O
their	O
first	O
work	O
in	O
1967	O
.	O
</s>
<s>
A	O
few	O
years	O
later	O
in	O
1977	O
,	O
Claude	O
Franceschi	O
published	O
the	O
very	O
first	O
book	O
about	O
vascular	O
ultrasonography	B-Application
,	O
L’investigation	O
vasculaire	O
par	O
ultrasonographie	O
Doppler	B-Algorithm
.	O
</s>
<s>
Soon	O
,	O
other	O
advances	O
in	O
electronics	O
and	O
piezoelectric	O
materials	O
enabled	O
further	O
improvements	O
which	O
meant	O
that	O
ultrasound	B-Application
was	O
quickly	O
adopted	O
for	O
use	O
in	O
medicine	O
due	O
to	O
its	O
rapid	O
,	O
accurate	O
diagnostic	O
capabilities	O
which	O
offered	O
the	O
possibility	O
of	O
prompt	O
treatment	O
.	O
</s>
<s>
Alongside	O
the	O
improving	O
imaging	O
technology	O
,	O
acoustic	O
Doppler	B-Algorithm
velocimetry	O
and	O
medical	B-Application
ultrasonography	I-Application
color	B-Algorithm
Doppler	I-Algorithm
were	O
developed	O
,	O
which	O
have	O
had	O
a	O
significant	O
impact	O
on	O
many	O
specialties	O
,	O
including	O
radiology	O
,	O
obstetrics	O
,	O
gynecology	O
,	O
angiology	O
and	O
cardiology	O
,	O
and	O
have	O
provided	O
even	O
greater	O
scope	O
for	O
ultrasound	B-Application
investigations	O
.	O
</s>
<s>
Since	O
1970	O
,	O
real-time	O
scanners	O
and	O
pulsed	O
Doppler	B-Algorithm
,	O
have	O
enabled	O
the	O
use	O
of	O
ultrasound	B-Application
to	O
study	O
the	O
function	O
of	O
the	O
venous	O
system	O
.	O
</s>
<s>
The	O
first	O
demonstration	O
of	O
color	B-Algorithm
Doppler	I-Algorithm
was	O
achieved	O
by	O
Geoff	O
Stevenson	O
.	O
</s>
<s>
Rapid	O
technical	O
advancements	O
in	O
transmission	B-Algorithm
tomography	I-Algorithm
made	O
possible	O
the	O
very	O
good	O
specificity	O
and	O
sensitivity	O
capability	O
of	O
this	O
technique	O
,	O
enabling	O
the	O
possibility	O
of	O
properly	O
seeing	O
the	O
superficial	O
tissues	O
.	O
</s>
