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150 Duplex ultrasound scanning for acute venous disease
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16. Mansour MA. Venous duplex ultrasound of the lower
extremity in the diagnosis of deep venous thrombosis. In: AbuRahma AF, Bandyk DF, eds. Noninvasive
Vascular Diagnosis: A Practical Guide to Therapy, 3rd
Ed. London: Springer-Verlag, 2013, 473–81.
17. Merritt CRB. Ultrasonographic demonstration of
portal vein thrombosis. Radiology 1979;133:425–7.
18. Benson CB and Frates MC. Ultrasound of the
hepatoportal circulation. In: AbuRahma AF and
Bandyk DF, eds. Noninvasive Vascular Diagnosis:
A Practical Guide to Therapy, 3rd Ed. London:
Springer-Verlag, 2013, 565–87.
19. Kearon C, Julian JA, Math M, Newman TE, and
Ginsberg JS. Noninvasive diagnosis of deep venous
thrombosis. Ann Intern Med 1998;128:663–77.
20. Laissy J-P, Cinqualbre A, Loshkajian A etal.
Assessment of deep venous thrombosis in the
lower limbs and pelvis: MR venography versus
duplex Doppler sonography. Am J Roentgenol
1996;167:971–5.
21. Tessler FN, Gehring BJ, Gomes AS etal. Diagnosis
of portal vein thrombosis: Value of color Doppler
imaging. Am J Roentgenol 1991;157:293–6.
22. Sottiurai VS, Towner K, McDonnell AE, and Zarins
CK. Diagnosis of upper extremity deep venous
thrombosis using noninvasive technique. Surgery
1982;91:582–5.
23. Falk RL and Smith DF. Thrombosis of upper extremity thoracic inlet veins: Diagnosis with duplex
Doppler sonography. Am J Radiol 1987;149:677–82.
24. Sajid M, Ahmed N, Desai M, Baker D, and Hamilton
G. Upper limb deep vein thrombosis: A literature
review to streamline the protocol for management.
Acta Haematol 20 07;118:10 –18.
★
25. Kearon C, Akl EA, Comerota AJ etal.
Antithrombotic therapy for VTE disease:
Antithrombotic therapy and prevention of thrombosis, 9th ed: American College of Chest Physicians
Evidence-Based Clinical Practice Guidelines. Chest
2012;141:e419S–94S.
★
26. Zierler BK. Ultrasonography and diagnosis of venous
thromboembolism. Circulation 2004;109(Suppl. I):
I-9–I-14.
27. Strothman G, Blebea J, Fowl RJ, and Rosenthal G.
Contralateral duplex scanning for deep venous
thrombosis in unnecessary in patients with symptoms. J Vasc Surg 1995;22:543–7.
28. Prandoni, P, Lensing AWA, Piccioli A, Bagatella P,
and Girolami A. Ultrasonography of contralateral
veins in patients with unilateral deep-vein thrombosis. Lancet 1998;352:786.
29. Pennell RC, Mantese VA, and Westfall SG. Duplex
scan for deep vein thrombosis—Defining who needs
an examination of the contralateral asymptomatic
leg. JVasc Surg 2008;48:413–6.
30. Le Gal G, Robert-Edabi H, Carrier M, Kearon C,
Bounameaux H, and Righini M. Is it useful to also
image the asymptomatic leg in patients with suspected deep vein thrombosis? J Thromb Haemost
2015;13:563–6.
31. Heit JA, Mohr DN, Silverstein MD, Petterson TM,
O’Fallon WM, and Melton LJ III. Predictors of recurrence after deep vein thrombosis and pulmonary
embolism: A population-based cohort study. JAMA
Intern Med 2000;160:761–8.
32. Siragusa S, Malato A, Anastasio R etal. Residual
vein thrombosis to establish duration of anticoagulation after a first episode of deep vein thrombosis: The Duration of Anticoagulation based on
Compression Ultrasonography (DACUS) study. Blood
2008;112:511–5.
33. Stephenson EJP and Liem TK. Duplex imaging
of residual venous obstruction to guide duration of therapy for lower extremity deep venous
thrombosis. J Vasc Surg Venous Lymphat Disord
2015;3:326–32.
34. Carrier M, Rodger MA, Wells PS, Righini M, and
Le Gal G. Residual vein obstruction to predict
the risk of recurrent venous thromboembolism
in patients with deep vein thrombosis: A systematic review and meta-analysis. J Thromb Haemost
2011;9:1119–25.
35. Donadini, MP, Ageno W, Antonucci E et al.
Prognostic significance of residual venous obstruction in patients with treated unprovoked deep vein
thrombosis. Thromb Haemost 2014;111:172–9.
36. Kyrle PA and Eichinger S. Clinical scores to predict recurrence risk of venous thromboembolism.
Thromb Haemost 2012;108:1061– 4.
37. Hamadah A, Alwasaidi T, Le Gal G etal. Baseline
imaging after therapy for unprovoked venous thromboembolism: A randomized controlled comparison of
baseline imaging for diagnosis of suspected recurrence. J Thromb Haemost 2011;9:2406–10.
13
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Duplex ultrasound scanning for chronic venous
obstruction and valvular incompetence
RAFAEL D. MALGOR AND NICOS LABROPOULOS
13.1 Introduction 151
13.2 Duplex ultrasound 151
13.3 Obstruction 152
13.4 Reflux 153
13.5 Technique 155
13.6 Role of DUS in understanding the
pathophysiology of CVD 157
13.1 INTRODUCTION
Venous obstruction and reux are the two pathologies that
lead to venous hypertension, which causes the sequelae of
chronic venous disease (CVD). Despite the high prevalence
of CVD and the number of studies that have been performed
in this area, the etiology of CVD is poorly understood. e
challenge to the clinician is to nd a method of reliably
evaluating a patient for CVD. e physical examination is
useful. Many of the signs and symptoms of CVD can be
detected by physical examination, but physical examination
alone is inadequate.
Phlebography, plethysmography, and duplex ultrasound (DUS) are the main methods for the evaluation of
the venous system. Computed tomography and magnetic
resonance imaging have also been utilized lately in CVD
workups, especially in cases where iliocaval obstruction is
suspected.1 Plethysmography is used in the assessment of
the amount of reux, the eciency of the calf muscle pump,
and obstruction. Phlebography is used when there is a need
for endovenous therapy and deep vein reconstruction.
Plethysmography is also recommended in patients with
advanced CVD if duplex scanning does not provide denitive information on pathophysiology.1 DUS has become the
test of choice for the evaluation of CVD in most patients as
it is safe, noninvasive, cost-eective, and reliable. Although
the evaluation of acute venous pathology has been discussed
in Chapter 18, it must be mentioned that such pathology can
recur in new or previously aected vein segments and can
worsen the clinical severity of CVD.
13.7 Progression of CVD 159
13.8 Recurrent varicose veins 160
13.9 Use of DUS before, during, and after treatment 160
References 162
e CEAP classication was developed by the American
Venous Forum in 1994 and revised in 2004 to delineate
the severity of CVD, improve standards of reporting, and
develop treatment plans for the various stages of the disease.2 It relies on the four components of clinical signs
(C), etiology (E), anatomy (A), and pathophysiology (P).
Recently, a more detailed venous score system, the Venous
Clinical Severity Score (VCSS), has been utilized to grade
the severity of CVD. e VCSS is composed of 10 categories
which mainly consider the degree of pain, amount of varicose veins, skin damage, and the use of compression stockings. Both the physical examination and diagnostic tests are
employed in order to report the patient’s condition before
and aer treatment.
13.2 DUPLEX ULTRASOUND
e choice of the ultrasound probe is important. e pulsewave Doppler of a 4–7-MHz linear array transducer is ideal
for the examination of most veins. Other multi-frequency
arrays can be used as well. e more supercial veins can
be evaluated using higher-frequency probes that give better
resolution. e deep veins and veins in obese patients are
evaluated using a 3-MHz curvilinear probe that provides
better depth of penetration. Lower-frequency probes are
also used to evaluate the venous system in the pelvis and
abdomen. Curvilinear lower-frequency transducers should
also be utilized whenever the depth of imaging is >6 cm
(large l imbs).
151
152 Duplex ultrasound scanning for chronic venous obstruction and valvular incompetence
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During imaging, low ow settings are most commonly
used. e pulse repetition frequency (PRF) is set at 1500 Hz
or lower. In cases of vein stenosis or arteriovenous stula,
the PRF is set higher, since the ow velocity is signicantly
elevated in such situations. e focus is set with the posterior wall (far wall in relation to the skin) to enable better
lateral resolution in the eld of imaging. e vein lumen
should be set to appear dark in the absence of stasis and
thrombosis. e time gain compensation is set according to
the echogenicity and depth of the relevant tissues in order
to perfect the imaging of the pertinent pathology. When
obtaining velocity waveforms, the gain is set to have a dark
background in order to avoid overestimation. If the signal
is weak because of depth, the gain is increased accordingly.
e angle of insonation in the venous system is oen set at
0°. However, because most veins run parallel to the skin, if a
precise velocity is needed, then the angle has to be corrected
to be parallel to the ow channel.
e examination room conditions should also be conducive to obtaining optimal results. e room should be warm
and comfortable and a warm gel must be utilized on the skin
in order to ensure that there is no spasm of veins at the time
of examination and that the veins are at their natural size.
13.3 OBSTRUCTION
Obstruction in the venous system can occur due to extrinsic
and intrinsic pathologies. Tumors, hematomas, cysts, aneurysms, and musculoskeletal structures can cause extrinsic
vein compression. However, the most common cause of
obstruction is venous thrombosis. Its diagnosis is critical, as
deep vein thrombosis (DVT) is obviously a signicant cause
of long-term morbidity and premature mortality in those
aicted with the disease.
e long-term consequences of DVT are devastating in
terms of numbers and cost of care. Post-thrombotic syndrome (PTS) is a term that is used to describe the sequelae
of CVD. e typical ndings are pain, a burning sensation,
itching, varicose veins, chronic limb swelling, skin discoloration, and ulceration. Aer a single episode of DVT,
the incidence of PTS has been reported to range from 23%
to 79%. A large prospective study showed an incidence of
about 25% at 5 years.
shown to increase the odds for developing PTS by six times.3
e sensitivity and specicity of DUS for identifying thrombosis is >95% proximal to the knee, whereas the accuracy
may decrease in the below-knee segment.4 e evaluation of
functional obstruction cannot be achieved with DUS, as it
assesses a single vein segment at a time. Unfortunately, it is
dicult to measure functional obstruction, since there are
no validated tests to quantify functional obstruction.
Duplex techniques for the evaluation of CVD are similar
to those used in the evaluation of acute venous thrombosis.
In chronic disease states, the major veins might be chronically obstructed. Collateralization and recanalization may
also occur. e major veins are seen in immediate proximity to the corresponding artery. If a vein is seen more than
3
Ipsilateral recurrent DVT has been
1 cm away from the artery, one must consider the possibility
of a dilated collateral vein. Normal venous Doppler signals
are obtained in cases where full recanalization has occurred
or in the presence of duplicated veins that were unaected
by the thrombotic process. e popliteal vein is duplicated
in 35%–40% of people and occasionally is triplicated. e
femoral vein in the thigh is duplicated in about 25%–30%
of people, and this duplication may have dierent patterns
along the course of the vein. e veins in the calf are oen
paired around the corresponding artery. A single calf vein
or a triplication may also be found. Aplasia of the posterior
tibial veins has also been reported. In cases of venous duplication or aplasia, direct visualization, attention to detail,
and experience with the ultrasound techniques are invaluable for reducing erroneous results. In patients with previous DVT, the technician has to be vigilant when scanning
the previously aected and the contralateral limb for recurrence of DVT. Risk factors for recurrent DVT are previous
ipsilateral DVT, age >65 years, residual thrombus, or previ-
3,5
ous iliofemoral involvement.
Knowing these risk factors
aids the operator when carefully seeking signs of recurrent
DVT, such as thrombus found in a new location, thrombus
extending >9 cm further in the vein, a previously recanalized segment that is not compressible, and thrombus thickness ≥2 mm for calf veins and ≥4 mm for proximal veins.
6
Venous ultrasound studies are reasonably well standardized. In brief, the patient is placed on the examination table in the reverse Trendelenburg position. e knee
is bent and externally rotated. e examination is started
below the inguinal ligament at the common femoral vein
and saphenofemoral junction (SFJ). e probe is placed in
transverse direction to the vein and compression is applied.
e probe is then turned longitudinally to evaluate ow and
augmentation. e veins are examined in 3–5-cm intervals. In a similar manner, all of the deep veins of the leg,
including the femoral, deep femoral, popliteal, peroneal,
soleal, gastrocnemial, and posterior tibial veins, are examined for obstruction. An examination of the anterior tibial
veins is not routinely performed due to their low incidence
of thrombosis, unless local symptoms or trauma to the
anterior leg compartment area are present. e supercial
veins, including the great saphenous vein (GSV) and small
saphenous vein (SSV), are then evaluated. Finally, in cases
of obstruction, it is important to check the iliac veins and
the inferior vena cava (IVC). In abdominal and pelvic veins,
mainly ow is evaluated, since compression can be dicult and uncomfortable for the patient. A normal venous
ow is phasic with respiration and is augmented with distal compression or is stopped with the Valsalva maneuver.
Asymmetry in ow velocity and waveform patterns at rest
and during ow augmentation in the common femoral
veins indicate proximal obstruction. However, the absence
of such asymmetry does not exclude obstruction. erefore,
when iliocaval obstruction is suspected, the full extent of
these veins must be imaged.
e presence of stenosis, usually from extrinsic compression, is recognized by a mosaic color pattern that denotes
13.4 Reflux 153
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post-stenotic turbulence, abnormal Doppler waveform at
the area of stenosis, slow ow, spontaneous contrast, and
vein dilatation prior to the stenosis.7 e vein diameter
reduction can be measured by planimetry, comparing the
smallest lumen to the normal lumen. Peak vein velocity
ratios comparing intra-stenotic to pre-stenotic peak velocities or comparing post-stenotic to pre-stenotic peak velocities can be calculated. In patients with a pressure gradient
across the stenosis ≥3 mmHg, the peak systolic velocity
(PSV) ratio has been shown to be >2.5. is is particularly
useful when investigating central vein stenosis.
7
e four components that should be examined in all
venous duplex examinations are visualization, compressibility, ow, and augmentation. ere are ways to potentially
distinguish acute obstruction from chronic obstruction
(Table 13.1). e veins with acute thrombosis are echolu-
cent, distended, and have smooth walls. In chronic thrombosis, the veins are echogenic, contracted, and have thick,
irregular walls (Figure 13.1). Acute thrombus is “spongy”
on compression examination, but will still keep the walls
of the vein from coapting with probe compression. On the
color ow examination, acute thrombus will have conuent ow channels. Chronic thrombus will either have multiple channels or collateralization. Intraluminal webs and
wall thickening, with or without reux, indicate a previous
thrombosis in the absence of visible thrombus. e presence
of dilated collateral veins indicates the presence of obstruction, but unfortunately, their absence cannot exclude it. It
is also possible for the veins to be fully recanalized without
any evidence of anatomic obstruction. However, the thickening and increased stiness of the vein wall can still result
in functional obstruction.
Signs and symptoms in both lower extremities are present when there is bilateral iliac vein obstruction or when the
IVC is involved. e iliac veins and IVC may have extrinsic
compression from masses (Figure 13.2). e extrinsic com-
pression can lead to signs and symptoms of CVD. In such
patients, thrombosis of the compressed vein is a common
event.
13.4 REFLUX
Venous reux is the reversal of ow in the veins of the lower
extremity. e reversal of ow in the vein can be subdivided
into physiologic and pathologic. Physiologic reversal of ow
accounts for the fraction of the second it takes for the valve
leaets to appose. A prospective study has demonstrated
that the acceptable physiologic reversal of ow is dierent
for various venous systems in the lower limb.6 e cut-o
value for reux, in the authors’ experience, in the common
femoral, femoral, and popliteal veins is >1000 ms. For the
supercial, deep femoral, deep calf axial, and muscular
veins, the value is 500 ms, and in the perforating veins (PVs)
it is 350 ms. It is postulated that in the larger veins with
fewer valves, the time it takes for the valve leaets to come
together is longer in comparison to smaller, shorter veins.
A recent multicenter prospective study has determined that
a reux of ≥0.5 seconds is accepted as abnormal.8 Dierent
patterns of reux are displayed in Figure 13.3.
It is important to dierentiate between primary, secondary, and congenital reux. is classication is based on the
pathophysiology of the reux. Congenital reux exists at
birth, but is rarely recognized early, since there is a lag in the
presenting signs and symptoms. Secondary reux is most
oen the result of thrombosis. e most common type of
reux is primary, where the cause has not been determined.
A study that has used the CEAP classication to investigate
the causes of CVD showed that congenital reux accounts
for 1%–3% of CVD, secondary reux accounts for 18%–28%
of CVD, and primary reux accounts for 64%–79% of CVD.
9
Table 13.1 Duplex ultrasound criteria used to differentiate acute versus chronic obstruction
Criterion
Size Distended No longer distended
Echogenicity Echolucent: acute
Lumen characteristics The lumen is not
Wall characteristics Thin and smooth Thickened Thickening with luminal reduction due to
Flow characteristics Absence of flow/
Thrombus
characteristic
Collateral veins Absent May be present Often found around the obstructed segments
Acute (days to
weeks)
thrombi
present or only
partially present
fillings defects
– Presence of tail Decreased linear extension of thrombus
Subacute (weeks to
months) Chronic (months to years)
Reduced; sometimes unable to be traced
due to lysis
Moderate
echogenecity
Recanalization with
adherence
Partial recanalization Partial recanalization with reflux. Enhanced flow
byduplex ultrasound
Echogenic: as the clot ages, dense material,
increased cellular components, fibroblasts,
and collagen deposits form.
Partial recanalization with compressible filling,
often has residual thrombus or vein wall
defects, and reflux may have a spongy feel
on compression
inflammatory response to the thrombus
in dilated collateral veins
154 Duplex ultrasound scanning for chronic venous obstruction and valvular incompetence
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(a) (b)
(c) (d)
W : 4.0 MHz
Right + 38.4
(e) (f)
– 38.4
cm/s
(g)
θ = 54°
(h)
Figure 13.1 (a) Acute thrombosis in the common femoral vein. There is absence of color, the vein is dilated (twice the
sizeof the adjacent common femoral artery in red) with a homogeneous echolucent texture. (b) Acute on chronic
thrombosis in the soleal vein in a patient with recent calf pain. The vein is dilated and has echogenic material (old
thrombus), and echolucent material (fresh thrombus). (c) Chronic thrombus with partial recanalization in the great
saphenous vein. Flow channels with reflux are seen over the old thrombus that appears as an echogenic band in
the lumen.
(d) Complete recanalization with prolonged reflux in the popliteal vein. Thickening is seen in the far wall.
(e)Chronic iliofemoral occlusion with collaterals from the inferior epigastric and internal iliac veins. (f) Chronic IVC
obstruction with partial recanalization. The lumen of the IVC is smaller than the adjacent aorta. The azygos vein is dilated
and larger than the aorta. (g) Nonphasic flow in a groin collateral in a patient with iliofemoral occlusion. (h) Chronic
occlusion of the external iliac vein in a female patient who underwent stenting for previous thrombosis. Flow is seen in the
adjacent artery. The vein has a small diameter and echogenic material in the lumen. The stent is seen in both the near and
the far wall as an echogenic rim between the wall and the thrombus.
(a)
(b)
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2
2
1
1
0.4
Figure 13.2 (a) Bilateral swelling in a patient with inferior
vena cava (IVC) compression. Notice the pitting edema
in both limbs after digital compression over the tibia.
(b)Compression of the IVC by a tumor at the level of the
liver. The lumen of the IVC at the site of compression
measured 0.4 mm whereas the normal distal segment
measured 1.4 mm. The color changes from blue in
the normal portion of the IVC to white at the area of
compression indicating significant vein stenosis.
1.4
13.5 TECHNIQUE
Reux can be elicited in two ways. During the Valsalva
maneuver, the intra-abdominal pressure is increased, and
this can lead to reversal of ow if there is valvular incompetence. is technique is mainly useful in the evaluation
of valves in the groin, as competent valves proximally will
limit its usefulness.
Compression and release distal to the point of examination on the limb is a reliable method of evaluating reux, and
is referred to as augmentation. With compression there is an
initial increased ow in the vein as the blood is pushed in the
normal direction of ow from distal to proximal. Once the
pressure is released, the blood ow reverses momentarily.
If there are competent valves, there is minimal to no back
13.5 Technique 155
ow. However, with incompetent valves, the blood continues to ow in the reverse direction. For the purposes of more
precise measurement and standardization, the use of automated pneumatic cus with rapid ination and deation is
essential. e cu is placed around the leg 5 cm below the
probe site. A 24-cm cu is used around the thigh, a 12-cm
cu around the calf, and a 7-cm cu around the foot. e
ination lasts for 3 seconds followed by rapid deation in
0.3 seconds. To ensure complete venous emptying and to
overcome the hydrostatic pressures from above, thigh cus
are inated to 80 mmHg, those on the calf to 100 mmHg,
and 120 mmHg is required for foot cus. Occasionally in
patients with signicant edema, the above techniques are
inadequate and dorsiexion/plantar exion is also used.
To obtain the best results, the examination should start
with the patient in the standing position, with the weight of
the patient on the contralateral limb. e limb of interest
should be slightly exed and externally rotated. If a patient
is unable to stand for the time required, the veins from the
mid-thigh and below can be assessed in the sitting position. If the test is performed on a bed, the torso should be
elevated to >45°. A tilt-table with a leg rest to keep weight
on the contralateral limb and reected backwards into a
60° position is another technique that can be used for reux
measurements.
e routine examination of the veins of the lower
extremity starts at the common femoral vein above the
junction of the femoral and deep femoral veins. e SFJ
at the terminal and pre-terminal valve and the associated
tributaries are examined next. is is followed by the popliteal and the deep calf veins. e GSV, SSV, their tributaries, and non-saphenous veins are examined in detail, as
these are the most common sites of reux. Reux in veins
that are not part of the GSV or SSV system are found in
about 10% of the patients. Veins of interest involved in nonsaphenous vein reux are the gluteal vein, postero-lateral
thigh PV, vulvar vein, lower posterior thigh vein, popliteal
fossa vein, knee perforator vein, and sciatic nerve vein.
10
e GSV can be identied and dierentiated from other
supercial veins because it is surrounded by two layers of
fascia in the saphenous eye.
11
e SSV is found in the triangular fascia and is surrounded by the crural fascia and
the medial and lateral heads of the gastrocnemius muscle.12
e tributaries of the supercial veins that are oen incompetent in the thigh are the anterior and medial accessory
veins, and in the calf they are the posterior and anterior
arch veins. ese veins should be examined along their full
length if they are incompetent.
Duplication of the saphenous veins is rare, reecting
<3% of patients with CVD.12 e most common anatomic
variations of the saphenous veins are segmental hypoplasia
and aplasia.13 Accessory veins ensuring good venous drainage are frequently found close to such segments.
13
PVs are the last to be examined. ey can be distinguished from the supercial and deep veins since they
course perpendicular to these veins and pierce the deep
fascia. e deep fascia is dense and echogenic and can
156 Duplex ultrasound scanning for chronic venous obstruction and valvular incompetence
Loyola University Med L7–4 38 mm PVasc/ven
2 : 32 : 50 pm F# 15 4.1 cm
(a)
Loyola Medical Center
L7–4 38 mm PVasc/ven
F# 48 3.1 cm
(b)
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Map 8
DynRg 50 dB
Persist med
Fr rate med
Col 68% Map 5
WF low
PRF 2000 Hz
Flow Opt : Med V
(c)
(e)
R T
+19.2
–19.2
cm/s
SV angle 60°
Dep 1.1 cm
Size 2.0 mm
Freq 4.0 MHz
WF low
Dop 59% Map 2
PRF 1515 Hz
cm/s
–10
–20
20
10
Map 8
DynRg 50 dB
Persist med
Fr rate med
Col 74% Map 5
WF low
PRF 2000 Hz
Flow Opt : Med V
(d)
(f)
10 : 59 : 05
R T
+19.2
–19.2
cm/s
SV angle –60°
Dep 1.9 cm
Size 2.0 mm
Freq 4.0 MHz
WF low
Dop 55% Map 2
PRF 2500 Hz
–40
–20
cm/s
20
40
(g)
Figure 13.3 (a) Normal saphenofemoral junction. During distal augmentation there is flow towards the heart (negative
deflection as blood traveling away from the transducer). After release of the compression there is a short duration of retrograde flow until the valve is closed. (b) Prolonged reflux in the great saphenous vein (GSV) below the knee. The vein has
a normal diameter indicating that a vein does not have to be dilated when it is incompetent. This patient had asymptomatic CEAP class 2 disease. (c) Reflux in the popliteal, medial gastrocnemial, and small saphenous vein (SSV). This patient
had a chronic thrombosis that was fully recanalized. He presented with CEAP class 4 and had pain and itching. (d) Reflux
in a lower calf medial perforator in a patient with a healed ulcer (C5). The vein was dilated (>6 mm) and had prolonged
outward flow. (e) Cross-sectional view of a focal dilation in the lower thigh GSV with a frozen valve seen at the 4 o’clock
position. (f) Dilation of the SSV in the upper calf with wall thickening in a patient with skin changes, edema, and varicose
veins in the posterior calf. The diameter of the SSV measured 8 mm and the reflux duration was longer than 5 seconds. (g)
Prolonged reflux from the medial gastrocnemius vein (GV) to the SSV. The SSV was incompetent from its junction with the
gastrocnemial vein at mid-calf to the lateral malleolus. The proximal SSV was normal.
be easily visualized on an ultrasound scan. ere are
approximately 150 PVs in the lower extremity, of which
only 20 are of clinical signicance in terms of reux possibly leading to clinical pathology. e normal direction
of ow is from the supercial to the deep veins through
the PVs. ese veins are examined using transverse and
oblique scanning, since their long axes are seen in these
planes. ey are found by following the course of the GSV,
13.6 Role of DUS in understanding the pathophysiology of CVD 157
N
N
LT
par
C1–3A EP AS+P PR C1–4S EP AS+P+D PR+O
N
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the SSV, and the tributaries. Outward ow in these veins
is seen only in the presence of supercial and deep vein
reux. Based on the current Society for Vascular Surgery
and American Venous Forum guidelines for the care of
patients with CVD, duplex scanning of the PVs should be
performed selectively.1 PVs are deemed to be “pathologic”
when an outward ow of duration of ≥500 ms, a diameter
of ≥3.5 mm, and a location beneath healed or open venous
ulcers (CEAP class C5–C6) are present.1 ese guidelines
aid physicians in making their decisions on whether or not
PVs need to be treated.
1
e results of an ultrasound examination in patients
with CVD are oen depicted in drawings. An example of
this is given in Figure 13.4. e le and right lower extremities have been drawn to scale and have skin, muscular,
and bony landmarks such as the popliteal skin crease, sartorious muscle, knee, and medial malleolus. Such drawings enable better understanding and interpretation of the
ndings and therefore facilitate the planning of treatment
in each limb.
Right
13.6 ROLE OF DUS IN UNDERSTANDING
THE PATHOPHYSIOLOGY OF CVD
e majority (70%–80%) of patients presenting wit h CVD are
symptomatic. ese symptoms include itching, ache, restless
limb, heaviness, burning, and ulceration. Varicose veins and
telangiectasias are present in 80% of patients. Skin changes
of some sort are seen in 20%–25%, and active or healed
ulcerations in 12%–14% of patients with CVD (Figure13.5).
Patients with C1 and C2 disease have reux conned to the
supercial system. As the clinical severity worsens (C3–C6),
the prevalence of incompetence in the perforator and deep
veins increases. In limbs with CVD, reux alone exists in
80% of patients, reux and obstruction are present in 17%
of patients, and only 2% of patients have obstruction alone.9
In addition, the combination of reux and obstruction has a
worse prognosis for the development of skin lesions.
e most common location of reux in patients with
CVD is the saphenous vein trunks and their tributaries,
irrespective of clinical class. ese veins are aected in 90%
Left
3
R
R
R
N
R
R
: POPV + MGV
tial recanalization with reux
R
R
R
R
R
R
R
R
Figure 13.4 Report of a duplex ultrasound examination in a patient with bilateral chronic venous disease (CVD). She was
a 53-year-old female with two pregnancies and a positive family history of CVD in both parents. She noticed signs and
symptoms of CVD after her second pregnancy, first in the left lower extremity and 2 years later in the right lower extremity. She had also developed thrombosis in the left lower extremity 7 years previously. LT, left; MGV, medial gastrocnemius
veins; N, no reflux; POPV, popliteal vein; and R, reflux.
158 Duplex ultrasound scanning for chronic venous obstruction and valvular incompetence
Class 0
1.3
Percentage (%)
0
Primary + secondary
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Figure 13.5 Presentation of 1000 consecutive limbs with chronic venous disease according to the CEAP classification.
of patients. Of the supercial veins, the GSV is involved in
70%–80% of cases, the SSV is involved in 15%–20%, and
non-saphenous veins are involved in about 10%. e deep
system is only aected in 30% of patients with CVD, and
the PVs in 20%.9 Complex patterns of reux are present in
patients with skin damage.14 Several studies have demonstrated that reux in the supercial system alone is the cause
of 17%–54% of venous ulcerations. Of all limbs with venous
ulceration, 74%–93% have reux in the supercial system.
is present in more than 50% of patients with ulceration. is
subclass of patients will benet from intervention directed
towards the supercial venous system.18 Isolated deep vein
reux occurs in <10% of patients.
popliteal vein reux has the strongest association with the
severity of CVD. Two vein systems are involved in ulcerated limbs in 52%–70% of patients, and all three systems are
involved in 16%–50% of patients.
the ulcer bed or within 2 cm of the ulcer have reux in 86%
of cases. However, perforator vein reux is found only in a
third of cases in this area.17 Saphenous reux can occur without SFJ and saphenopopliteal junction (SPJ) incompetence;
therefore, ligation of these junctions may not be appropriate
in such patients.
obstruction is found in any of the systems. In these patients,
other causes of ulceration should be evaluated.
in varicose limbs more frequently than in healthy ones
(P < 0.001). It greatly inuences the path of the reux and
the anatomy of the varicose veins. GSV segmental hypoplasia can be detected pre-operatively by duplex ultrasonography. Its occurrence may inuence surgical management
for two main reasons: in about 68% of varicose limbs with
segmental hypoplasia, the distal GSV is competent; if the
distal GSV is incompetent, its size and ow direction are
normalized by treating the accessory vein that bypasses the
hypoplastic segment.
worthy of discussion, as treatment of the saphenous trunks
Class 1
Class 2
Class 3
Class 4
Class 5
Class 6
Primary
Secondary
Congenital
Superficial
Perforating
Deep
Reflux
Obstruction
Reflux + obstruction
15–17
Supercial reux, with or without perforator reux,
17–19
Among the deep veins,
17–19
e veins that are in
20, 21
In 2.6%–4.0% of patients, no reux or
5.9
20.4
4.3
8.2
6.1
0.9
1.8
010203040
22
21.6
24.7
24.2
16.7
It has been shown that saphenous hypoplasia occurs
13
Several patterns of reux in the supercial veins are
38.3
68.3
90.7
28.8
81.6
50 60 70 80 90 10
may be avoided. In fact, there are occasions where both the
GSV and SSV should be spared. An incompetent anterior
accessory vein with or without involvement of the SFJ in
the absence of GSV reux is found in 9% of patients. Aer
treating the anterior accessory vein, at 1-year follow-up, no
patients had reux in the GSV and 95% were satised with
the treatment. In a large series of patients with reux in the
SSV system, 3.1% had incompetence in the thigh extension
of the SSV only.12 In another series where the thigh extension was studied, in the GSV and SSV system, reux was
found in 4.7%.23 Reux in the tributaries alone was detected
in 9.7% of limbs with CVD. e most common site was the
posterior arch vein.
24
Reux in non-saphenous veins, such as those of the
vulvar, gluteal, posterolateral thigh, and other locations, is
found in 10% of limbs with CVD.10 ese are mostly multiparous female patients with a mean of three pregnancies.
On all of these occasions, treatment can be targeted by
ultrasound and the saphenous veins spared. Reux in nonsaphenous veins is seen in Figure 13.6.
It has been suggested that in patients with primary reux
in the supercial and deep system, deep venous reux may
be directly linked to supercial reux. e reux circuit
theory of venous overload states that reux in the supercial system at the level of the perforators and major
supercial to deep vein junctions will ow into the deep
system and overload the deep system. is leads to dilatation and the development of reux in the deep system. It
has been demonstrated that, by surgically correcting the
reux in the supercial system, the deep system reux is
also eliminated in more than 90% of patients.25 In a prospective study, deep reux in patients with primary CVD
was shown to occur near the SFJ, SPJ, and gastropopliteal
junction.26 It was more likely to occur when the reux at
these junctions had high peak velocity and long duration.
e reux in the deep veins was usually segmental and of
shorter duration than post-thrombotic reux. A recent
study of 30 limbs has demonstrated that signicant hemodynamic compromise is present when deep vein reux is
(a) (b)
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(c) (d)
13.7 Progression of CVD 159
Figure 13.6 Examples of reflux in nonsaphenous veins. (a) Varicose tributaries are seen in the right popliteal fossa of a male
patient who presented with pain and itching. The varicosities disappear above the popliteal skin crease as they dive deeper
to join the popliteal vein. (b) Significant reflux in the vein of the popliteal fossa of the same patient. The vein is dilated and
varicose and pierces the deep fascia just above the popliteal skin crease. It unites with the lateral aspect of the popliteal vein
above the saphenopopliteal junction. (c) Reflux in the dilated and tortuous veins of vastus medialis muscle. These veins were
connected with a perforating vein at the lower thigh that was in continuity with posteromedial varicose tributaries.
ovarian vein reflux in a 24-year-old woman with three pregnancies. She presented with left vulvar veins that were extending
from the groin medial to the GSV to the posterolateral calf. The ovarian vein measured 8.8 mm in diameter.
caused by supercial vein reux only when the popliteal
vein valves are incompetent.
27
Most PVs have at least one subfascial bicuspid valve that
prevents reux from the deep system to the supercial system. e role of PV incompetence in the development of
the signs and symptoms of CVD remains unclear. However,
there is evidence to suggest that the number of incompetent PVs and the sizes of competent and incompetent PVs
increase with worsening CVD.
28,29
It has also been reported
that patients with increasing numbers of incompetent PVs
have a higher venous lling index. e venous lling index
is known to correlate well with the severity of CVD.
incompetence occurs more in the calf than in the thigh.
29
PV
16,28,29
ere are more incompetent PVs found in the lower and
e correction of reux in the supercial system has
been shown to eliminate reux in the PV. is is not the
case when the deep system is incompetent.31 In a prospective study where PVs were treated with surgical ligation
using DUS guidance, it was shown that recurrence of PVs at
3 years was very common (76%).32 e recurrent PVs were
due to neovascularization or the development of incompetence in new sites, and not because of poor surgery.
DUS can also identify other uncommon pathologies in
the veins, such as aneurysms, tumors, and phlebosclerosis
(Figure 13.7). ese pathologies are not usually associated
with the signs and symptoms of CVD unless there is concomitant reux or obstruction. However, their diagnosis is
important, and can alter management.
(d) Left
middle thirds of the medial calf. Most PVs that are >3.5 mm
in diameter will be incompetent.28 However, the sensitivity
13.7 PROGRESSION OF CVD
of size alone determining incompetence is low, as about a
third of the reuxing PVs have a diameter of <3.5 mm. e
duration of outward ow and local hemodynamics worsen
in PVs when both the supercial and deep veins connected
to those PVs are incompetent.
28,30
e development of new
PV reux is closely related to reux in the supercial system. In primary CVD, reux in PVs develops in an ascending manner through the adjoining incompetent supercial
vein, in a descending manner from the re-entry ow of a
reuxing supercial vein, and in new locations where the
supercial veins are also involved.
It was previously hypothesized that because of hydrostatic
pressure, reux must start at the level of the iliac or common
femoral valves and develop in a retrograde manner. However,
studies on the morphology, biochemistry, and function of
the venous wall have demonstrated that changes can occur
in any vein segment, irrespective of the site and function of
the valves. With the use of DUS, it has been clearly shown
that in the early stages of CVD, reux develops in most
people in the lower thigh, knee, and calf, without having a
26
connection to the groin area.
Reux, therefore, may have
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