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160 Duplex ultrasound scanning for chronic venous obstruction and valvular incompetence
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(a) (b)
2
2
1
Figure 13.7 (a) Cross-sectional view of an anterior accessory saphenous vein aneurysm in the upper thigh measuring
23mm. The adjacent vein segment that is partially seen at the 7 o’clock position measured 3.4 mm. The aneurysm is free
of thrombus as seen from the echolucent lumen. This was also documented by its full compressibility.
tion of the great saphenous vein (GSV) near wall in the lower thigh. Acoustic shadowing is seen throughout the calcification. Phlebosclerosis occasionally is seen in the lower extremity veins and has no significant implications in contrast to
calcification in intestinal veins that may lead to significant morbidity.
(b) Dense calcifica-
an ascending progression, descending progression, both, or
may be multifocal. ese ndings are further supported by
a recent study that examined patients below the age of 30
years with varicose veins and compared them with another
group of patients over the age of 60 years.33 It was shown that
most oen the saphenous and non-saphenous tributaries are
diseased, and this was more common in younger patients.
Junctional involvement was signicantly less prevalent in
the younger group (38% vs. 59%, P = 0.0005).
A prospective study of 126 limbs including three distinct
groups of patients with primary, secondary, and no signs or
symptoms of CVD showed that secondary CVD progresses
faster than primary CVD. e authors demonstrated that
at 5-year follow-up, skin damage was more prominent in
patients with secondary CVD, and that those skin changes
were seen earlier in the course of the disease in patients with
secondary CVD compared to primary CVD.34 Another
study that followed 116 limbs in 90 patients studied the progression of reux in CVD and its relation to physical ndings.35 ese patients had two or more DUS examinations
prior to operation since the procedure was delayed for various reasons. It was demonstrated that in 73.3% of patients,
there was no change in the DUS examination and extent of
reux. In 13 limbs, there was advancement of CEAP staging, of which seven also had progression on DUS as well.
Progression of reux was seen in 26.7% of patients. ese
results indicated that physical examination or DUS alone
were not reliable for predicting the progression of disease.
Progression of reux occurred mostly with anatomic extension in an ascending or descending manner and in both
directions. Few patients developed reux in a dierent area.
13.8 RECURRENT VARICOSE VEINS
In 1998, an international committee met in Paris to establish guidelines for recurrent varices aer surgery (REVAS).
eir ndings and classication were to supplement the
CEAP system, taking into account intervention. is system accounts for true recurrence, residual disease, and
progression of existing disease. e prevalence of REVAS
has been reported to be 20%–80%.36 Perrin and colleagues
performed a multicenter study in order to evaluate the
etiology, pathophysiology, and progression of disease in
R E VAS .37 ey enrolled 170 patients with 199 aected limbs
in 14 dierent institutions over a period of 1 year. e areas
most aected by recurrent reux in these patients were the
SFJ in 47% of patients and the perforators in 55% of the
limbs. Recurrent reux resulted from technical failure to
ligate the SFJ, neovascularization in cases of SFJ disease,
and failure to recognize signicantly diseased perforators in
the pre-operative evaluation. More patients tended to have
below-knee reux aer their procedures rather than thigh
reux. is is because the entire GSV is oen obliterated
or removed above the knee and the veins below the knee
are simply ligated or stripped. Technical failure occurred in
19% of patients, and neovascularization occurred in 20%. A
combination of the two was seen in 17% of the patients. In
35% of the recurrences, the cause was unknown. Recurrence
developed in a new site in 32% of the limbs. Family history
had the highest prevalence of recurrence (68%). is is not
a surprising nding, since the strong relationship between
hereditary and venous disease has been established.
38
Women tended to have more procedures to correct recurrence than men, even though the severity of recurrence was
greater in men.
13.9 USE OF DUS BEFORE, DURING,
AND AFTER TREATMENT
DUS can also be used as an adjunctive tool during therapy and for follow-up. e type of treatment is based on
the baseline DUS. In the rst examination, a map is made
of the distribution and extent of reux and obstruction.
Additional tests may be necessary if deep vein reconstruction, endovenous or bypass operations to relieve obstruction, and pelvic vein reux treatment are planned.
eect of the procedure at a local level (i.e., improvement,
elimination, or worsening of the reux and obstruction) can
39
e
13.9 Use of DUS before, during, and after treatment 161
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be documented. In addition, the eect of the procedure in
veins that are proximal and distal to the site of the treatment
can be assessed. However, DUS evaluates one short venous
segment at a time. e overall eect of the treatment in the
limb can be assessed better with physiological testing, such
as plethysmography and pressure measurements.
Endovenous treatment of the supercial veins and PVs by
ablation or sclerotherapy is now performed with DUS guidance. It is important to document the vein diameter, proximity to the skin, tortuosity, obstruction, and areas with
hypoplasia and aplasia in order to have a good treatment
plan.40 Saphenous vein diameter is measured 3 cm below its
respective femoral (SFJ) or popliteal (SPJ) junction, and at
mid-thigh for GSV.
Guidelines 2.3.0 of the American Venous Forum on duplex ultrasound scanning for chronic venous obstruction and valvular
incompetence
No. Guideline
2.3.1 Duplex scanning is recommended as the first diagnostic
2.3.2 We recommend that the four components included in
2.3.3 Duplex scanning is recommended to distinguish acute from
2.3.4 We suggest that reflux is elicited in two ways: increased
2.3.5 We recommend that reflux is elicited in the upright position
2.3.6 A cut-off value of 1 second is recommended to define
2.3.7 We recommend that in patients with chronic venous
40
test for all patients with suspected chronic venous
obstruction or valvular incompetence. The test is safe,
noninvasive, cost-effective, and reliable.
duplex scanning examinations for chronic venous disease
are visualization, compressibility, venous flow, and
augmentation.
chronic venous occlusion.
intra-abdominal pressure using a Valsalva maneuver or
manual or cuff compression and release of the limb distal
to the point of examination.
in one of two ways: either with increased intra-abdominal
pressure using a Valsalva maneuver to assess the common
femoral vein and the saphenofemoral junction or, for the
more distal veins, the use of manual or cuff compression
and release of the limb distal to the point of examination.
abnormally reversed flow (reflux) in the femoral and
popliteal veins and of 500 ms for the great saphenous
vein, the small saphenous vein, and the tibial, deep
femoral, and the perforating veins.
insufficiency, duplex scanning of the perforating veins is
performed selectively. We recommend that the definition
of “pathologic” perforating veins includes those with an
outward flow of duration of 500 ms, with a diameter of
3.5 mm and a location beneath healed or open venous
ulcers (CEAP class C5–C6).
During the procedure, DUS is used to obtain percutaneous venous access and to guide the wire and catheters.
Accurate positioning at the treatment area of interest is easily achieved as the tip of the catheter is placed in the correct
location safely. Before the ablation takes place, the tumescence uid is injected around the vein. e goal is to create
a halo sign over the entire length of the treated segment,
with the vein being collapsed around the catheter. During
the catheter pullback, the immediate eect on the vein can
be observed. e vein is re-examined at the end of the procedure to ensure complete ablation and that the saphenous
junctions and deep veins are free of thrombus. If adjunct
procedures are performed, such as phlebectomies or sclerotherapy, DUS can also be used to guide that treatment as
Grade of
Grade of
recommendation
(1: strong;
2: weak)
1 A
1 A
2 B
2 B
1 A
1 B
1 B
evidence (A: high quality;
B: moderate quality;
C: low or very low
quality)
162 Duplex ultrasound scanning for chronic venous obstruction and valvular incompetence
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well. In many centers, various forms of sclerotherapy are
being performed as sole treatments, and this is also carried
out under DUS guidance.
41,42
Follow-up of endovenous therapy is important in order
to monitor its success and to identify complications such
as DVT. It is also recommended to perform a DUS study
1 year aer endovenous thermal ablation in order to determine whether the GSV or SSV remain obliterated. If obliterated, it is likely that the vein will remain so for at least
3–5 years.40 is 1-year follow-up study is also important
in order to identify newly developed incompetent veins at
the same treated site (due to neovascularization or dilation
of pre-existent veins) or new sites. ese ndings will aid
further treatment when deemed appropriate by the patient
and the specialist.
40
REFERENCES
1. Gloviczki P, Comerota AJ, Dalsing MC etal.; Society
for Vascular Surgey, American Venous Forum. The
care of patients with varicose veins and associated
chronic venous diseases: Clinical practice guidelines
of the Society for Vascular Surgery and the American
Venous Forum. J Vasc Surg 2011;53(5 Suppl.):2S–48S.
2. Eklöf B, Rutherford RB, Bergan JJ etal. American
Venous Forum international ad hoc committee for
revision of the CC. Revision of the CEAP classification for chronic venous disorders: Consensus statement. J Vasc Surg 2004;40(6):1248–52.
3. Prandoni P, Bernardi E, Marchiori A etal. The long
term clinical course of acute deep vein thrombosis of the arm: Prospective cohort study. BMJ
2004;329(7464):484–5.
4. Kearon C, Julian JA, Newman TE, and Ginsberg JS.
Noninvasive diagnosis of deep venous thrombosis.
McMaster diagnostic imaging practice guidelines
initiative. Ann Intern Med 1998;128(8):663–77.
5. Labropoulos N, Jen J, Jen H, Gasparis AP, and
Tassiopoulos AK. Recurrent deep vein thrombosis:
Long-term incidence and natural history. Ann Surg
2010;251(4):749–53.
6. Labropoulos N, Waggoner T, Sammis W, Samali
S, and Pappas PJ. The effect of venous thrombus location and extent on the development of
post-thrombotic signs and symptoms. J Vasc Surg
2008;48(2):407–12.
7. Labropoulos N, Borge M, Pierce K, and Pappas PJ.
Criteria for defining significant central vein stenosis
with duplex ultrasound. J Vasc Surg 2 0 07;4 6 (1):101–7.
8. Lurie F, Comerota A, Eklöf B etal. Multicenter
assessment of venous reflux by duplex ultrasound.
J Vasc Surg 2012;55(2):437–45.
9. Kistner RL, Eklöf B, and Masuda EM. Diagnosis
of chronic venous disease of the lower extremities: the “CEAP” classification. Mayo Clin Proc
1996;71(4):338–45.
10. Malgor RD and Labropoulos N. Pattern and
types of non-saphenous vein reflux. Phlebology
2013;28(Suppl. 1):51–4.
11. Caggiati A. Fascial relationships of the long saphenous vein. Circulation 1999;100(25):2547–9.
12. Labropoulos N, Giannoukas AD, Delis K etal.
The impact of isolated lesser saphenous vein
system incompetence on clinical signs and symptoms of chronic venous disease. J Vasc Surg
2000;32(5):954–60.
13. Caggiati A and Mendoza E. Segmental hypoplasia of
the great saphenous vein and varicose disease. Eur J
Vasc Endovasc Surg 2004;28(3):257–61.
14. Labropoulos N, Patel PJ, Tiongson JE, Pryor L, and
Leon LR Jr., Tassiopoulos AK. Patterns of venous
reflux and obstruction in patients with skin damage
due to chronic venous disease. Vasc Endovascular
Surg 2007;41(1):33– 40.
15. Hanrahan LM, Araki CT, Rodriguez AA, Kechejian
GJ, LaMorte WW, and Menzoian JO. Distribution of
valvular incompetence in patients with venous stasis
ulceration. J Vasc Surg 1991;13(6):805–811; discussion
811–2.
16. Labropoulos N, Delis K, Nicolaides AN, Leon M, and
Ramaswami G. The role of the distribution and anatomic extent of reflux in the development of signs
and symptoms in chronic venous insufficiency. J Vasc
Surg 1996;23(3):504 –10.
17. Labropoulos N, Giannoukas AD, Nicolaides AN,
Ramaswami G, Leon M, and Burke P. New insights
into the pathophysiologic condition of venous ulceration with color-flow duplex imaging: implications
for treatment? J Vasc Surg 1995;22(1):45–50.
18. Barwell JR, Davies CE, Deacon J etal. Comparison
of surgery and compression with compression
alone in chronic venous ulceration (ESCHAR
study): Randomised controlled trial. Lancet
2004;363(9424):1854–9.
19. Yamaki T, Nozaki M, and Sasaki K. Color duplex
ultrasound in the assessment of primary venous leg
ulceration. Dermatol Surg 1998;24(10):1124–8.
20. Labropoulos N, Giannoukas AD, Delis K etal.
Where does venous reflux start? J Vasc Surg
1997;26(5):736–42.
21. Labropoulos N, Leon M, Nicolaides AN, Giannoukas
AD, Volteas N, and Chan P. Superficial venous
insufficiency: Correlation of anatomic extent of
reflux with clinical symptoms and signs. J Vasc Surg
1994;20(6):953–8.
22. Labropoulos N, Manalo D, Patel NP, Tiongson J,
Pryor L, and Giannoukas AD. Uncommon leg ulcers in
the lower extremity. J Vasc Surg 2007;45(3):568–73.
23. Delis KT, Knaggs AL, and Khodabakhsh P.
Prevalence, anatomic patterns, valvular competence,
and clinical significance of the Giacomini vein. J Vasc
Surg 2 0 0 4;40(6):1174– 83.
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24. Labropoulos N, Kang SS, Mansour MA, Giannoukas
AD, Buckman J, and Baker WH. Primary superficial
vein reflux with competent saphenous trunk. Eur J
Vasc Endovasc Surg 1999;18(3):201–6.
25. Walsh JC, Bergan JJ, Beeman S, and Comer
TP. Femoral venous reflux abolished by greater
saphenous vein stripping. Ann Vasc Surg
1994;8(6):566–70.
26. Labropoulos N, Tassiopoulos AK, Kang SS, Mansour
MA, Littooy FN, and Baker WH. Prevalence of
deepvenous reflux in patients with primary
superficial vein incompetence. J Vasc Surg
2000;32(4):663–8.
27. Papadakis KG, Christopoulos D, Hobbs JT, and
Nicolaides AN. Descending phlebography in
patients with venous ulceration: Hemodynamic implications. Int Angiol 2015;34(3):263–8.
28. Labropoulos N, Mansour MA, Kang SS, Gloviczki P,
and Baker WH. New insights into perforator vein
incompetence. Eur J Vasc Endovasc Surg 1999;
18(3):228 –34.
29. Ibegbuna V, Delis KT, and Nicolaides AN.
Haemodynamic and clinical impact of superficial,
deep and perforator vein incompetence. Eur J Vasc
Endovasc Surg 2006;31(5):535–41.
30. Delis KT, Husmann M, Kalodiki E, Wolfe JH, and
Nicolaides AN. In situ hemodynamics of perforating veins in chronic venous insufficiency. J Vasc Surg
2001;33(4):773–82.
31. Stuart WP, Adam DJ, Allan PL, Ruckley CV, and
Bradbury AW. Saphenous surgery does not correct
perforator incompetence in the presence of deep
venous reflux. J Vasc Surg 1998;28(5):834–8.
32. van Rij AM, Hill G, Gray C, Christie R, Macfarlane J,
and Thomson I. A prospective study of the fate of
venous leg perforators after varicose vein surgery.
J Vasc Surg 2005;42(6):115 6 –62 .
33. Caggiati A, Rosi C, Heyn R et al. Age-related
variations of varicose veins anatomy. J Vasc Surg
2006;44:1291–5.
34. Labropoulos N, Gasparis AP, Pefanis D, Leon LR Jr.,
and Tassiopoulos AK. Secondary chronic venous
disease progresses faster than primary. J Vasc Surg
2009;49(3):704–10.
35. Labropoulos N, Leon L, Kwon S etal. Study
of the venous reflux progression. J Vasc Surg
2005;41(2):291–5.
36. Perrin MR, Guex JJ, Ruckley CV etal. Recurrent
varices after surgery (REVAS), a consensus
document. REVAS group. Cardiovasc Surg
2000;8(4):233–45.
37. Perrin MR, Labropoulos N, and Leon LR Jr.
Presentation of the patient with recurrent varices
after surgery (REVAS). J Vasc Surg 2006;43(2):327–
34; discussion 334.
38. Cornu-Thenard A, Boivin P, Baud JM, De Vincenzi I,
and Carpentier PH. Importance of the familial factor
in varicose disease. Clinical study of 134 families.
J Dermatol Surg Oncol 1994;20(5):318–26.
39. Nicolaides AN, Cardiovascular Disease Educational
and Research Trust, European Society of Vascular
Surgery, The International Angiology Scientific
Activity Congress Organization, International Union
of Angiography, Union Internationale de Phlebologie
at the Abbaye des Vaux de Cernay. Investigation
of chronic venous insufficiency: A consensus
statement (France, March 5–9, 1997). Circulation
2000;102(20):E126–63.
40. De Maeseneer M, Pichot O, Cavezzi A etal.;
Union Internationale de Phlebologie. Duplex
ultrasound investigation of the veins of the lower
limbs after treatment for varicose veins—UIP
consensus document. Eur J Vasc Endovasc Surg
2011;42(1):89–102.
41. Guex JJ. Foam sclerotherapy: An overview of use
for primary venous insufficiency. Semin Vasc Surg
2005;18:25 – 9.
42. Smith PC. Chronic venous disease treated by
ultrasound guided foam sclerotherapy. Eur J Vasc
Endovasc Surg 2006;32:577–83.
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Evaluation of venous function by indirect
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noninvasive testing (plethysmography)
FEDOR LURIE AND THOM W. ROOKE
14
14.1 Technical principles 165
14.2 Practical applications 166
Venous disease is typically divided into two broad, distinct
categories: acute (usually caused by thrombosis) and chronic
(most oen a combination of chronic venous obstruction,
valvular incompetence, and/or muscle pump dysfunction).
In acute venous thrombosis, it is important to not only diagnose the presence of thrombus, but also to identify its location, determine its age, and assess any ongoing changes (i.e.,
clot propagation, organization, recanalization, etc.). Duplex
ultrasound has become the standard test for addressing
these diagnostic needs.
e optimal approach for the assessment of chronic
venous disease (CVD) is less clear, owing to the increased
complexity required to evaluate the separate hemodynamic contributions of obstruction, reux, and pump
function. Despite this uncertainty, the need for detailed
assessment is signicant. Management of CVD has made
signicant advances in the past three decades, and new
treatment modalities, ranging from surgical reconstruction of venous valves to oce-based minimally invasive
treatment of supercial veins to endovascular treatment of
acute and chronic venous obstruction, are now available.
In this environment, the demand for reliable testing techniques that are capable of answering key clinical questions
is growing.
Venous testing (usually with duplex scanning) is a key
component of the CEAP
provides a framework for characterizing patients with
CVD. e diagnosis of disease and the denition of clinical class are based on clinical evaluation, while noninvasive testing is used to identify pathophysiological changes
(reux or obstruction) in individual anatomical segments
of the venous system, and, in some cases, to dene etiology. Designed as a descriptive classication, CEAP does not
address the severity of the disease. Even clinical class “C”
1
classication approach, which
14.3 Summary 167
References 168
may not be directly related to clinical severity. For example,
patients with venous ulcers who are successfully treated
remain classied as C5 even when completely asymptomatic
and free of signs of venous disease. In addition, the pathophysiologic part of the classication—the “P” of CEAP—
is also purely descriptive. It includes the identication of
reux and obstruction, but does not quantify the severity of
either reux or obstruction. While assessment of the clinical severity of CVD is possible by using instruments such
as Venous Clinical Severity Score,2 the severity of reux
or obstruction cannot be dened by imaging modalities
such as ultrasound and venography—not in individual segments, and denitely not for an entire extremity. Despite
the fact that the goal of CVD treatment is to correct the
hemodynamic abnormalities, the assessment of CVD severity over time and aer treatment is especially challenging,
because the relationships between clinical manifestations
and underlying pathophysiology are complex and poorly
dened.
ese limitations dictate the need for testing modalities that can assess the global function of the venous system of the lower extremity. Venous pressure measurements
can serve this purpose, but are invasive and unpractical.
Indirect noninvasive tests, such as the various forms of
plethysmography, are alternatives.
14.1 TECHNICAL PRINCIPLES
e indirect noninvasive tests most oen used in the evaluation of patients with CVD are air plethysmography (APG)
and strain-gauge plethysmography (SGP). Both of these
techniques assess venous function by measuring changes
in the size of the extremity in response to exercise, postural change, and the application and release of a venous
165
166 Evaluation of venous function by indirect noninvasive testing (plethysmography)
Volume change
Time
mL
mL
Volume change
Time
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150
125
100
75
50
25
0
–25
Figure 14.1 Air plethysmography tracings of a patient 3 years after femoropopliteal deep venous thrombosis. (A)
Unaffected extremity; (B) extremity with venous obstruction has decreased venous capacitance (VC), and decreased maximum venous Pc is the pressure in the occlusion cuff. MVO: maximal venous outflow.
tourniquet. e main assumption of these examinations is
that the arterial blood supply to the extremity and transcapillary uid exchange do not change signicantly in response
to the utilized maneuvers. Changes in the extremity’s volume are therefore attributed to lling and emptying of the
veins (Figure 14.1).
A
B
Photoplethysmography and light reection rheography
calculate changes in tissue blood density by measuring the
intensity of reected light. Because of the inability of the
light to penetrate deeper through the skin, diculties in
calibration, and poor specicity, these techniques currently
have found little application in the evaluation of CVD.
VC
MVO
MVO
1 second
4
APG and SGP use dierent models for the calculation
of volume changes. APG measures changes in pressure in a
14.2 PRACTICAL APPLICATIONS
measurement cu calibrated to reect volume changes. SGP
calculates volume changes from changes in circumference.
It assumes the extremity to have a cylindrical shape with
an even distribution of volume changes in response to the
testing maneuvers. e two methods give quantitatively different, but qualitatively identical information.
3
Both APG and SGP require considerable patient cooperation. Consistency in performing exercise, maintaining
position, and distributing weight between the legs can contribute signicantly to variability in the results. External
mechanical, thermal, and chemical (pharmacological)
stimuli may also cause signicant changes in the size of the
venous lumen and in venous capacitance. All of these factors, along with changes in central venous hemodynamics
and arterial supply, should be considered when the results
of these indirect tests are analyzed.
Although plethysmography studies can identify both
obstruction and reux, they are unable to allocate these
changes to specic venous segments. Duplex ultrasound
is the preferable and standard technique for the identication of reux and, when feasible, obstruction. When
venous obstruction is suspected, but not identied by
duplex scan, plethysmography can help to overcome the
low sensitivity of the ultrasound for the detection of
venous obstruction.
An advantage of these indirect tests over ultrasound
is their ability to provide a quantitative measure of the
impact of obstruction and valvular insuciency on the
overall function of the venous system of the lower extremity. In addition, plethysmography can provide a quantitative assessment of muscle pump function (Figure 14.2). is
Figure 14.2 Assessment of muscle pump function by air plethysmography. The ejection fraction is calculated by dividing
the EV by the VV and is expressed as a percentage by multiplying by 100. The residual volume fraction is calculated by
dividing RV by the VV, and is also expressed as a percentage. VV: functional venous volume; EV: ejected volume (single
tiptoe exercise); RV: residual volume after 10 consecutive tiptoe exercises.
250
225
200
175
150
125
100
75
50
25
EV
VV
RV
0
14.3 Summary 167
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information can also be used in the assessment of treatment
outcomes and for follow-up.
5,6
14.2.1 Identification and assessment
of obstruction
e physiological roles of the venous system of the lower
extremities include adjustments to changes in circulating
blood volume and central hemodynamics by the accumulation and release of additional volumes of blood. To
serve this need, under normal conditions, veins maintain
a signicant reserve capacity. Venous obstruction can
measurably decrease this reserve. Increased resistance
to outow decreases the rate of emptying of more distal
veins. Identication and assessment of venous obstruction by plethysmography is based on the estimation of the
following two parameters: venous capacitance and venous
resistance.
Measurements of the calf volume increase in response
to venous occlusion by tourniquet, and the calf volume
decreases aer its rapid release; this constitutes the basis
of venous occlusion plethysmography. Although venous
pressure rises to equal the pressure of the tourniquet,
blood accumulates in the veins of the studied extremity.
Because veins easily increase their size under low pressure and become inextensible aer the pressure exceeds
50–80 mmHg, they reach the level of maximal capacity,
which is reected in the maximally increased size of the
calf.
Rapid release of the tourniquet creates a pressure gradient between extremity veins, where the pressure is equal to
the pressure of the tourniquet and the central venous pressure, which is close to zero. Dening the pressure gradient
makes possible the calculation of venous resistance by measuring the rate of decrease in the calf volume aer the tourniquet is released. In extremities with venous obstruction,
this resistance can exceed normal values by three-fold or
more,7 unless the developed collateral ow osets the eects
of axial vein obstruction.
14.2.2 Assessment of reflux severity
Leg elevation or exercise can be used to decrease the blood
volume that has accumulated in the veins of an extremity. When an extremity is positioned vertically, rell of the
veins can occur from relatively slow arterial inow or, in
the case of valvular incompetence, by rapid reuxing from
a larger proximal segment. Measuring the rate of venous
rell, usually indexed to 90% of the total volume, provides
an estimate of overall valvular competence or the severity
of reux in extremities with no venous obstruction. When
limited to patients with isolated supercial vein incompetence, venous relling by plethysmography correlates well
with great saphenous vein reux as determined by duplex
8
scan.
14.2.3 Assessment of muscle pump
function
Active evacuation of blood from the venous system of the
lower extremity against hydrostatic pressure is a function
of muscle pumps that integrate the eects of muscle contractions with the ability of the venous valves to provide
unidirectional ow. Evaluation of muscle pump function
in patients with CVD is important, because its impairment contributes signicantly to the severity of CVD.9
Improvement in muscle pump function through physical
therapy10 and/or elastic compression11 can have benecial
therapeutic eects.
e decrease in calf volume following a single calf muscle contraction, and the amount of blood not expelled by
repeated contractions, can be indexed to the functional
venous volume (ejection fraction and residual volume
fraction, respectively) in order to assess the calf muscle
pump function. Plethysmographic ndings correlate well
with measurements of ambulatory venous pressure.
Its noninvasive nature makes this indirect test the only
practicable option for the evaluation of the calf muscle
pump.
12
14.2.4 Clinical correlations
Clinical correlations with the results of indirect noninvasive tests remain to be dened. Although potential for the
prediction of ulceration has been demonstrated in early
works,13 more careful analysis revealed that deterioration of
venous hemodynamics (as measured by plethysmography)
parallels clinical severity only before skin changes develop12
or during ulcer healing.
9
14.2.5 Reliability
The reliability and repeatability of plethysmography have
been demonstrated by Christopoulos andNicolaides,13
and were later confirmed by others.14 The limits of
reproducibility, however, differ significantly between
the reports, and should be defined by systematic
investigation.
14.3 SUMMARY
Plethysmography is currently the only practical noninvasive modality for global physiologic evaluation of the venous
system of an extremity. It not only provides valuable information on the impact of reux and obstruction on overall
venous function, but also provides a way to assess the calf
muscle pump. Plethysmography is a noninvasive modality
that complements duplex ultrasound, and can be used to
monitor venous hemodynamics over time and/or evaluate
treatment outcomes.
168 Evaluation of venous function by indirect noninvasive testing (plethysmography)
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Guidelines 2.4.0 of the American Venous Forum on the evaluation of venous function by indirect noninvasive testing
(plethysmography)
Grade of evidence
(A:high quality;
B:moderate quality;
C:low or very low
quality)
No. Guideline
2.4.1 We suggest that venous plethysmography is used selectively for the
noninvasive evaluation of the venous system in patients with simple
varicose veins (CEAP class C2).
2.4.2 We suggest that venous plethysmography is used for the noninvasive
evaluation of the venous system in patients with advanced chronic
venous disease if duplex scanning does not provide definitive
information on pathophysiology (CEAP class C3–C6).
Grade of
recommendation
(1: strong;
2:weak)
2 C
2 B
REFERENCES
1. Eklöf B, Rutherford RB, Bergan JJ etal. Revision of
the CEAP classification for chronic venous disorders:
Consensus statement. J Vasc Surg 2004;40:1248–52.
2. Vasquez MA, Rabe E, McLafferty RB etal. Revision
of the venous clinical severity score: Venous outcomes consensus statement: Special communication
of the American Venous Forum Ad Hoc Outcomes
Working Group. J Vasc Surg 2010;52:1387–96.
3. Louisy F, Cauquil D, Andre-Deshays C etal. Air
plethysmography: An alternative method for assessing peripheral circulatory adaptations during spaceflights. Eur J Appl Physiol 2001;85:383–91.
4. Bays RA, Healy DA, Atnip RG, Neumyer M, and
Thiele BL. Validation of air plethysmography, photoplethysmography, and duplex ultrasonography in
the evaluation of severe venous stasis. J Vasc Surg
19 94 ; 2 0 :721–7.
5. Gillespie DL, Cordts PR, Hartono C etal. The role of
air plethysmography in monitoring results of venous
surgery. J Vasc Surg 1992;16:674–8.
6. Rhodes JM, Gloviczki P, Canton L etal. Endoscopic
perforator vein division with ablation of superficial
reflux improves venous hemodynamics. J Vasc Surg
19 98;28:8 39– 47.
7. Barnes RW, Collicott PE, Sumner DS, and Strandness
DE Jr. Noninvasive quantitation of venous
hemodynamics in postphlebitic syndrome. Arch Surg
1973;107:807–14.
8. Lattimer CR, Azzam M, Kalodiki E, and Geroulakos G.
Venous filling time using air-plethysmography correlates highly with great saphenous vein reflux time
using duplex. Phlebology 2014;29:9 0 –7.
9. Araki CT, Back TL, Padberg FT etal. The significance
of calf muscle pump function in venous ulceration.
J Vasc Surg 1994;20:872–7.
10. Padberg FT Jr., Johnston MV, and Sisto SA.
Structured exercise improves calf muscle pump function in chronic venous insufficiency: A randomized
trial. J Vasc Surg 200 4; 3 9 :79– 87.
11. Christopoulos DG, Nicolaides AN, Szendro G etal.
Air-plethysmography and the effect of elastic compression on venous hemodynamics of the leg. J Vasc
Surg 1987;5:148–59.
12. Welkie JF, Comerota AJ, Katz ML etal.
Hemodynamic deterioration in chronic venous disease. J Vasc Surg 1992;16:733–40.
13. Christopoulos D, Nicolaides AN, Cook A etal.
Pathogenesis of venous ulceration in relation to the calf muscle pump function. Surgery
1989;106:829–35.
14. Yang D and Sacco P. Reproducibility of air plethysmography for the evaluation of arterial and venous
function of the lower leg. Clin Physiol Funct Imaging
2002;22:379–82.
Direct contrast venography
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HARALDUR BJARNASON
15
15.1 Introduction 169
15.2 Lower extremity ascending venography 169
15.3 Lower extremity descending venography 173
15.1 INTRODUCTION
e introduction of X-rays by Dr. Wilhelm Konrad Roentgen
in 1895 and the subsequent injection of contrast medium
into vessels led to a better understanding of the anatomy
and function of the vascular system. Venography became
a signicant part of the diagnostic armamentarium in the
1970s, and enabled clinicians to diagnose deep vein thrombosis (DVT) reliably, without the need to base the diagnosis
entirely on clinical ndings, since they are poor and imperfect ways of identifying oen deadly conditions.
Direct venography requires the infusion of contrast into
a peripheral vein, and relies on preferential ow of the contrast medium towards the heart. e contrast medium will
mix with the blood, making the blood opaque. e blood
ow and, thereby, the inner lumen of the vessels, can then
be followed with uoroscopy, and still images (X-rays) can
be taken and reviewed. is will not only give an image of
the anatomy, but also of vascular pathology aecting the
lumen of the vessel. As the blood ows along a gradient
towards the heart, one can also get an impression of the
hemodynamics in the vessels. e venous circulation can
be altered or inuenced, for example, by placing a tourniquet around a limb, forcing the contrast-mixed (enhanced)
blood to ow into the deeper venous system. is technique is commonly used to evaluate DVT or to look for
incompetent perforator veins. A tourniquet at the knee
level can also be applied to slow down contrast ow into
the central veins.
Because contrast is heavier than blood, contrast will layer
in the dependent part of the vessel, and high-lying veins may
not ll. As the contrast is layered at the dependent portions
of the larger veins, one may not see the entire circumference
of the vessel. is is a common pitfall of venography.
1
15.4 Upper extremity venography 174
References 175
15.2 LOWER EXTREMITY ASCENDING
VENOGRAPHY
Ascending venography, as the name implies, is based on
contrast ow in the bloodstream that is upward or central
in the direction of the heart along pressure gradients. is
is the traditional venography, and was one of the most commonly performed radiologic procedures until ultrasound
replaced it for the diagnosis of DVT.2 Upper extremity
venography is also technically an ascending venography,
but the term is mainly used for lower extremity venograms.
Ascending venography can be used to examine deep veins,
supercial veins, and—as the connections between these
two—the perforating veins. Introduced rst in 1923 by Dr.
Berberich and Dr. Hirsch,3 contrast venography became the
gold standard for diagnosing DVT when Dos Santos demonstrated its utility for imaging blood clots in 1938.
4
15.2.1 Technique
Rabinov et al.1 and others5 described the technique of
ascending venography in 1971 and 1972. e procedure is
preferentially performed on a tilt-table, with the head end
of the table raised 40–60°. At the foot end of the table, there
should be a “footboard” with an elevation upon which the
patient will rest the contralateral leg; the leg being examined should be non-weight bearing. An 18–20-gauge plastic
catheter (Angiocath) is placed into a peripheral dorsal foot
vein. e more peripheral the needle is placed, the better,
because the contrast should be dispersed evenly into the
venous bed. Distal directed puncture is recommended for
that reason. One should avoid medial foot vein access, as the
contrast will then preferably ow into the greater saphenous
vein, rather than the deep venous system.
169
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