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Chapter
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5
Noninvasive Examination of the Patient Before Sclerotherapy
Figure 5.27 Anomalies such as this duplication of the great saphenous
vein (arrow) may be visualized with a duplex scanner.
Figure 5.29 Injection into the saphenofemoral junction (SFJ) may be
performed under ultrasonic guidance. The needle is seen inside of the SFJ
(arrow).
(Courtesy Robert M. Knight, MD)
SSV
POP
Figure 5.28 The termination of the small saphenous vein (SSV) can usually
be visualized quite easily with duplex scanning. After release of the calf
compression, showing reflux. POP, popliteal vein.
sum of the peak refluxes in the GSV, SSV, and popliteal vein
was less than 10 mL/second. A sum of greater than 15 mL/
second was associated with a high incidence of these seque-
8,106
lae.
In addition, superficial venous reflux alone may cause
ulceration if the peak flow is greater than 7 mL/second.
In summary, advantages provided by duplex scanning
include evaluating the anatomy of the main saphenous trunks
and recurrences, injecting difficult areas under ultrasonic guidance, determining the presence of fibrosis, and quantifying
both reflux and forward flow. Unfortunately, both the Doppler
and duplex scanners are usually used to obtain only anatomic
information, thus leaving the actual hemodynamic effect of
the various abnormalities unknown. Functional studies may
therefore be necessary in certain situations.
104
107
Figure 5.30 Duplex scanning defines the saphenous vein and its
relationship to the superficial fascia and the deep or muscular fascia. The
superficial fascia, after arching over the great saphenous vein, fuses with the
muscular fascia to create a saphenous compartment. This compartment has
been called the ‘Egyptian eye’ in duplex scanning, as shown in this scan.
Photoplethysmography
The most widely used functional evaluation for presclerotherapy purposes is photoplethysmography (PPG).
Various forms of plethysmography have been used to evaluate
venous function since 1956,
correlate well with venographic findings
112
and they have been shown to
113
and ambulatory
venous pressure (AVP) measurements. In one study of 338
paired measurements of PPG and AVP, the correlation coefficient was 0.9.
108
The principle of PPG is quite simple, and
the test is easy and quick to perform. An infrared light source
and sensor are attached with adhesive to the medial aspect of
the lower leg, approximately 10 cm proximal to the medial
malleolus. The infrared light is transmitted into the leg to a
depth of approximately 0.5 to 1.5 mm, within the subdermal
venous plexus, where it is absorbed by hemoglobin in red
blood cells. Of the light that is not absorbed, a certain amount
returns to the sensor. Therefore, the amount of infrared light
reflected is inversely proportional to the volume of blood in
the skin. Once a baseline level is reached, the patient is asked
108–111
Figure 5.31 Ultrasound can be used to
https://t.me/med1917
differentiate thrombosis (A) from sclerosis (B).
(Horizontal white line indicates the diameter of the
vessel.)
(Courtesy P. Raymond-Martimbeau, MD)
A
Noninvasive Diagnostic Techniques
B
A
Figure 5.32 A, Photoplethysmography measures venous emptying during,
and refilling after, exercise of the calf and foot muscles. B, Emptying is
accomplished with 5 to 10 dorsiflexions of the foot.
B
to actively dorsiflex the foot 5 to 10 times, which activates the
calf muscle pump and produces venous outflow (Fig. 5.32).
With a reduced volume of blood in the calf and the subdermal
plexus, more light is reflected and the tracing shows a gradual
deflection (the direction of the deflection depends on the
VRT
Start
exercise
Figure 5.33 Photoplethysmography. Light reflection is enhanced as the
calf muscle is exercised and blood is pumped out of the leg. A reduction in
light reflection is seen once the leg is allowed to rest. The venous refilling
time (VRT) indicates the degree of reflux, although it is not quantitative.
End
exercise
electronics of the particular instrument). At the conclusion of
exercise, the patient is asked to relax and the tracing then
either returns to the original baseline value or levels off at a
new value of light transmission. The time required for this
value to be reached, the venous refilling time (VRT), provides
information on the presence and degree of reflux of blood
through either superficial or deep veins (Fig. 5.33).
Normally, refilling of blood occurs only through the arterial circuit and takes at least 20 to 25 seconds. A value less
than 20 seconds indicates the presence of an abnormal refilling channel, namely retrograde flow through incompetent
superficial or deep veins. Repeating the test while firmly compressing a particular vein allows the physician to assess the
degree of hemodynamic disturbance contributed by that vein.
Specifically, if the VRT lengthens from 15 to 35 seconds when
a vein is compressed, the examiner can be assured that this
105
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Noninvasive Examination of the Patient Before Sclerotherapy
106
vein is contributing significantly to the patient’s problem.
Similarly, in the setting of both superficial and deep venous
incompetence, by compressing the superficial veins the examiner theoretically can prevent reflux of blood through these
veins and observe the effect of the deep venous system alone.
If the VRT lengthens significantly when a tourniquet is placed
around the thigh to occlude the superficial veins, this implies
the dominance of the superficial system in the patient’s
pathology. If the VRT remains essentially unchanged, the
examiner can assume that the deep veins are the primary
problem. A word of caution must be mentioned, however,
relating to the method of compression of the vein(s). A simple
tourniquet, such as that used in phlebotomy, is used frequently and has the advantage of compressing all of the superficial veins, even those that are not suspected of being enlarged
and insufficient. However, it is important to be aware that this
type of compression may not adequately compress all of the
superficial veins, particularly large, thick-walled varicosities.
The need for the awareness just mentioned is especially
important in obese patients, but it is also necessary in patients
of normal weight. By using a duplex scanner to visualize the
flow through the GSV, McMullin et al
114
found that the pressure within a 2.5-cm-wide tourniquet required to prevent
reflux through the vein varied between 40 and 300 mmHg in
the 40 patients studied. Therefore, manual compression
applied directly to the vein being considered is the preferred
method because it allows more reliable interruption of the
flow and gives reproducibly accurate results.
VRT has been found to correlate well with AVP measurements, which have long been considered the gold standard in
the functional evaluation of venous hemodynamics. VRT may
vary between 20 and 65 seconds when AVP is below 40 mmHg,
but a VRT of less than 15 seconds is found only if the AVP is
higher than 40 mmHg.
relationship between their value and the incidence of venous
ulceration.
8,116
115
AVP measurements show a linear
Photoplethysmography may be used to quantify the blood
changes within the subdermal plexus, thus quantifying the
degree of reflux. This involves performing an in vivo calibration maneuver that allows the examiner to assign a numeric
value to the deflections on the tracing.
117,118
The transducer is
placed on the leg in its usual location while the patient rests
in the supine position, and the tracing on the recorder is set
to a zero baseline. The patient then stands, bearing weight on
the opposite leg, and after the tracing levels off, the gain is
adjusted so that the deflection reflects the calculated hydrostatic pressure in the superficial veins, measured by the distance from the right atrium to the site of the transducer on the
leg. This maneuver is repeated until the zero baseline and
standing levels of subdermal plexus blood content reproducibly reflect the hydrostatic pressures. The decrement in the
tracing is then proportional to the degree of fall in AVP, as
measured by invasive venous pressure recordings.
Plethysmography has been vigorously defended and advocated by some.
this tool because of its lack of correlation with duplex scan-
120
ning.
119
However, others have questioned the use of
The authors of this study stated, ‘These results do not
warrant the continued use of photoplethysmography for surgical decision-making in patients with suspected venous
insufficiency.’
Recent studies have demonstrated the efficacy of PPG in
evaluating venous hemodynamics.
121,122
A PPG system can be
calibrated to quantify the blood volume displacement with
leg elevation and/or exercise. In a study of patients with isolated superficial venous disease, digital PPG was found to give
reproducable results.
123
A determination of venomuscular
pump efficiency has been demonstrated to quickly gauge the
severity of venous disease. The use of PPG may also allow the
practitioner to assess the effectiveness of superficial vein
treatment.
Light reflection rheography
Light reflection rheography (LRR), which is basically a form
of PPG, was intended to improve on the original PPG
124,125
system.
sources, the infrared light beam can be focused at a standardized depth of penetration (0.3–2.3 mm) to cover the subcutaneous venous plexus. Dermal pigment, such as that
commonly found in patients with chronic venous insufficiency, is concentrated in the more superficial layers of the
skin and interferes with light transmission, yielding inaccurate
and variable values. It was hoped that by focusing its light
beam on the deeper tissues, the LRR would not be as affected
by the tissues containing the majority of the pigment. This did
not prove to be the case, however, and it was felt that calibration of the system might neutralize the effect of variables such
as skin thickness, skin pigment, and local blood volume on
light absorption. This improvement is now available as digital
PPG (D-PPG) or calibratable PPG (C-PPG).
The D-PPG contains a computer that permits changes in
light intensity from the infrared light source according to the
optical properties of the skin. The machine emits a standard
light intensity and awaits reflection of the unabsorbed light.
If it is below a certain level, the intensity of the emitted light
is automatically increased until the intensity of reflected
light reaches a level at which the machine can function accurately. This was demonstrated nicely by Kerner et al,
recorded essentially the same response to dorsiflexion even
after the leg was covered with a dark paint.
The C-PPG is essentially the same as the D-PPG, except that
the changes in light intensity are adjusted manually. This
device was tested on normal subjects and on patients with
venous disease. By comparing the time with 90% refilling, or
by combining the results obtained during postural changes
and dorsiflexion in order to obtain exercise drainage volume,
it was possible to significantly differentiate patients with
venous ulcers from those with varicose veins and from the
normal controls.
include venous filling volume and pump efficiency.
The usefulness of PPG in the assessment of venous valvular
insufficiency is undisputed; however, claims that it is accurate
in diagnosing DVT are controversial. The general statement
that a ‘picket fence’ pattern (Fig. 5.34) produced by the 10
dorsiflexions with essentially no vertical movement off of the
baseline is diagnostic of DVT is certainly incorrect, because
there are many false-positives using this criterion. In a study
of 30 limbs, the correlation coefficient between venous emptying and AVP was only 0.73.
at the University of Miami,
related well with the presence of acute DVT as documented by
venography. As shown in Figure 5.35, the finding of a slope
(R/T) of less than 0.31 mm/s predicts the presence of DVT
with a 96% sensitivity. Still, LRR alone currently is not
considered sufficient to make the diagnosis of DVT, and at
least one other noninvasive test is required to confirm the
diagnosis.
Figure 5.34 A ‘picket fence’ pattern may indicate deep venous thrombosis
but may also be seen with chronic venous insufficiency without thrombosis.
On account of its incorporating three light
115
126,127
who
115
Other parameters that can be calculated
124
However, in a study performed
128
the slope of the deflection cor-
50 mm
Millimeters
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A B C D E
∆R
Re
15 sec
T VRT
0 10 20 30 40
5 15 25 35 45 50
Figure 5.35 Usefulness of photoplethysmography in the diagnosis of deep
venous thrombosis (DVT) may be improved by examination of the slope
R/T; less than 0.31 mm/s predicts the presence of DVT with a 96% sensitivity.
R, refilling; T, time; VRT, venous refilling time.
Figure 5.36 The air plethysmograph consists of a long tubular polyvinyl-
chloride chamber that surrounds the entire leg. This chamber is inflated to
6 mmHg and is connected to a pressure transducer, an amplifier, and a
recorder. A smaller bag is placed between the air chamber and the leg
for calibration.
5:148, 1987.)
(From Christopoulos DG, Nicolaides AN, Szendro G, et al: J Vasc Surg
30 sec
Seconds
EV
90%
VV
VV
RV
VFT90
Seconds
90%VV
= VFI
VFT90
Figure 5.37 Diagramatic representation of a typical recording of volume
changes during a standard sequence of postural changes and exercise
using the air plethysmograph. A, Patient in supine position with leg
elevated 45 degrees; B, patient standing with weight on nonexamined leg;
C, single tiptoe movement; D, 10 tiptoe movements; E, patient standing
with weight on nonexamined leg; EF, ejection fraction; EV, ejected volume;
RV, residual volume; RVF, residual volume fraction; VFI, venous filling index;
VFT, venous filling time; VV, functional venous volume.
Nicolaides AN, Szendro G, et al: J Vasc Surg 5:148, 1987.)
Table 5.5 Venous filling index (VFI) and sequelae of venous disease
Chronic
VFI (mL/s)
<3
3–5 12 — 19
5–10 46 46 61
>10
Swelling (%)
— — —
76 58 76
EV
× 100 = EF
VV
Ulceration
(%)
RV
× 100 = RVF
VV
(From Christopoulos DG,
Skin Change (with
or without Ulcer)
Noninvasive Diagnostic Techniques
Air plethysmography
Air plethysmography (APG) is one technology that is just as
simple to use and potentially supplies a great deal of additional information compared with the conventional PPG.
This device consists of a 14-inch-long, tubular, polyvinylchloride air chamber that surrounds the leg from knee to
ankle. This is inflated to 6 mmHg and connected to a pressure
transducer, an amplifier, and a recorder. A smaller bag placed
between the air chamber and the leg is used for calibration by
injecting a certain volume of air or water and measuring the
change in the recording that is associated with that volume
(Fig. 5.36). Parameters assessed include: (1) functional venous
volume (VV), or the volume in the leg while the patient
stands; (2) venous filling time 90 (VFT90), or the time required
to achieve 90% of the VV; (3) venous filling index (VFI), or
90% VV/VFT90; (4) ejection volume (EV), or the volume
expelled from the leg with one tiptoe motion; (5) residual
volume (RV), or the volume at the end of 10 tiptoe motions;
and (6) residual volume fraction (RVF), or RV/VV100
(Fig. 5.37).
In a study of 22 patients with superficial venous insufficiency and nine patients with deep venous disease, VV was
found to be elevated in 80% of patients.
130
VFT90 was greater
than 70 seconds in normal limbs, 8 to 82 seconds in limbs
with superficial venous insufficiency, and 9 to 19 seconds in
limbs with deep venous disease. In normal limbs the VFI was
less than 1.7 mL/second, in limbs with superficial venous
insufficiency it was 2 to 30 mL/second, and in limbs with deep
venous disease the value was 7 to 28 mL/second. Ejection
129
fraction (EF) appeared to show better discrimination than EV.
The RVF was 20% in normal legs, 45% in legs with superficial
venous insufficiency, and 60% in legs with deep venous
disease (Fig. 5.38). A linear correlation with r = 0.83 was
present between RVF and AVP. In another study of 104
patients,
107,131
VFI was found to correlate with the incidence
of sequelae of venous disease such as chronic swelling, skin
changes, and ulceration (Table 5.5). In a third study of 205
132
limbs,
the same authors found an increasing incidence of
ulceration in patients with diminished EF and elevated VFI
(Table 5.6) and found that the RVF showed a good correlation
(r = 0.81) with the incidence of ulceration and AVP
measurements.
The real advantages of this method are its ability to quantitate reflux with the VFI and thus determine prognosis, and
its ability to measure calf muscle pump function through the
determination of the EF.
107,130–133
Still, APG measurements
should not be used in a vacuum. They should be combined
with Doppler or duplex findings and clinical evaluation, since
a great deal of overlap in values between normal and abnormal occur, decreasing the predictive value of abnormal APG
measurements.
134
Neglen and Raju
135
demonstrated quite well
107
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Noninvasive Examination of the Patient Before Sclerotherapy
A B
25
150
20
100
VFT (sec)
50
N SVI DVD N SVI DVD
C D
150
100
EF (ml)
50
N SVI DVD N SVI DVD
Figure 5.38 Air plethysmography. Results of, A, venous filling time 90
(VFT90); B, venous filling index (VFI); C, ejected volume (EV); D, ejection
fraction (EF). DVD, limbs with deep venous disease; N, normal limbs; SVI,
limbs with superficial venous incompetence.
AN, Szendro G, et al: J Vasc Surg 5:148, 1987.)
15
VFI (ml/sec)
10
5
100
EV (%)
50
(From Christopoulos DG, Nicolaides
in their evaluation of 118 limbs that VFI alone had a positive
predictive value of 66% in separating clinical severity class 0
or class 1 from class 2 or class 3. VFI combined with information gleaned from duplex scanning had a positive predictive
value of 83%.
Validation of use of APG in clinical practice has been
achieved by some.
136,137
However, in clinical practice, the use
of APG appears to be limited. Part of the problem is the difficulty in testing a large number of patients in a busy clinical
setting. Another is the fact that the skin changes of severe
chronic venous insufficiency are caused by many factors, and
the data obtained by APG can represent only the hemodynamic factor and not the effects of leukocyte infiltration, activation, and leukocyte–endothelial interactions that produce
the inflammatory response.
138
Perhaps the most carefully performed evaluation of the use
of APG was accomplished under David Sumner’s direction in
Springfield, Illinois.
139
In his report, he stated that, ‘We conclude that plethysmographic measurements of functional
venous parameters do not discriminate well between limbs
with uncomplicated varicose veins and limbs with ulcers or
stasis dermatitis and that the venous filling index correlates
poorly with the presence of incompetent veins and their diameters.’ Both duplex scanning and plethysmography seem to be
necessary for a complete evaluation of limbs with chronic
venous insufficiency.
Foot volumetry
Yet another method for evaluation of the functional state of
the venous system is foot volumetry.
early 1970s, this technique has not earned a prominent place
in phlebology, probably because of certain logistics of performing the test. However, it is necessary to have an accurate
way to measure leg swelling either for evaluation of chronic
venous disorders (day-to-day edema measurement) or calf
pump function assessment.
146
feet in an open water-filled plethysmograph (Fig. 5.39). The
water level is monitored by a photoelectric sensor, and changes
in foot volume are continuously measured, first while the
patient is standing still, then during the performance of 20
knee bends, and again while standing still. The parameters
measured include the volume of blood expelled from the foot
during exercise, the flow rate after exercise, and the time
required for half and then full refilling to occur. Norgren
143
et al
have shown good correlation between foot volumetry
and invasive venous pressure measurements in control subjects (r = 0.662) and in patients with varicose veins (r = 0.760)
but poor correlation in patients with deep venous valvular
insufficiency (r = 0.410). In their study, venous pressure measurements differed significantly in patients with varicose veins
and controls but were similar in patients with primary varicose
veins and those with deep venous valvular insufficiency.
140–145
Introduced in the
The patient stands with their
Table 5.6 Effect of venous filling index (VFI) and ejection fraction (EF) on incidence of venous ulceration
VFI < 5
VFI < 10
VFI > 10
EF, ejection fraction; VFI, venous filling index.
From Christopoulos DG, et al: Surgery 106:829, 1989.
108
EF > 40% EF < 40%
Limbs W/Ulcers Limbs W/Ulcers
Total no. of limbs No. % Total no. of limbs No. % P
41 1 2 19 6 32
37 11 30 19 12 63
32 13 41 27 19 70
<0.01
<0.02
<0.05
Table 5.7 Functional venous studies
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Photoplethysmography Foot Volumetry Air Plethysmography
Ease of use Easy
Hygienic
5-min test
Information obtained Presence of reflux
Superficial vs deep
Deep venous thrombosis*
*Limited sensitivity and specificity.
Easy
Communal bath
5 to 10-min test
Presence and degree of reflux
Calf muscle pump function
PTS Suspicion or documented history of DVT
Level 1
assessment:
CEAP grading
CEAP C ≥ 2
Level 2 : Duplex
+ Plethysmo or APG
+ Superficial tourniquets test
Deep venous insufficiency
(DVI)
± Superficial venous
insufficiency (SVI)
CO or C1
Requires practice by patient
Hygienic
5 to 10-min test
Presence and degree of reflux
Superficial vs deep
Calf muscle pump function
Level 2:
Duplex
Plethysmo
No deep
venous
insufficiency
Significant SVI Treatment of SVI
End check-up,
conservative
treatment
Possible treatment
of superficial venous
insufficiency (SVI)
Use of Noninvasive Techniques
Figure 5.39 The apparatus for foot volumetry consists of an open
water-filled plethysmograph that allows continuous measurement of foot
volume at rest and during exercise through monitoring of the water level by
a photoelectric float sensor.
(Courtesy Lars Norgren, MD)
However, with the use of foot volumetry, there were significant differences between all three groups. Thus, although it is
possible that foot volumetry is inaccurate in this important
categorization, it is likely that this technique is more sensitive
in distinguishing these groups than are venous pressure measurements.
with exercise and the refilling time increase after treatment of
varicose veins.
144
It has been shown that both the volume expelled
145
Therefore, this test could be used to evaluate
the success of a particular treatment, to follow the effect of
different stages in treatment, and to monitor the severity of
chronic venous insufficiency. It does not, however, allow
localization of a particular site of reflux, thus limiting its usefulness for presclerotherapy evaluation when compared with
other methods (Table 5.7–5.10, Fig. 5.40).
Use of Noninvasive Techniques
Each of the previously described techniques has advantages,
limitations, and uses in specific situations. Prohibitive cost or
limited access may preclude the use of the most sensitive and
accurate method. The following section discusses a reasonable
use of various noninvasive techniques for a variety of situations commonly encountered in the everyday practice of sclerotherapy (Table 5.11).
Many practitioners have noted changes in the findings of
flow and reflux depending on timing within the menstrual
Prominent or isolated DVI
CEAP C ≥ C4b
and conceivable deep
venous repair
Level 3 :
Ascending and descending
venograms + ambulatory
venous blood pressure.
Arm foot gradients
endovenous.
Figure 5.40 Organization chart of venous investigations work-up in case of
suspicion of post-thrombotic syndrome (PTS). (From Perrin M, Gillet JL, Guex J-J:
Encycl M
éd Chir. Editions médicales et scientifiques, Paris, 2003, Elsevier SAS, Angéiologie
19-2040 [12p].)
No improvement
C 2, 3, 4a
and/or
not conceivable
deep vein repair
Potential deep venous repair
Re-assessment
level 1
End check-up
cycle, time of day, recent use of compression hosiery, and
psychologic stress of the patient. Clearly, there are enough
experimental data to support a physiologic cause for these
fluctuations.
147
Therefore, an effort to examine patients in the
most physiologic circumstances (e.g. premenstrually, late in
the day) may be rewarded by a more revealing study.
Since the previous edition, ultrasound duplex scanning has
gained definitive popularity and is becoming widely available
almost everywhere. Therefore, duplex scanning is now the
preferred tool for initial and most complete assessment of
chronic venous disorders. Continuous wave Doppler has been
moved down to clinical assessment (like a stethoscope).
109
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Noninvasive Examination of the Patient Before Sclerotherapy
Table 5.8 The instrumental evaluation of post-thrombotic syndrome – relevance of investigations according to considered abnormalities
Venous
Anatomy Venous Reflux
NONINVASIVE
Continuous-wave Doppler Nil Identification errors Nil Nil Nil Obsolete
Color duplex scan Excellent Excellent, indicates
duration and situation
Photoplethysmography Nil Good but not
discriminating
Air plethysmography Nil Excellent but global Good Doubtful Nil Not available
Strain gauge plethysmography
and rheo-plethysmography
Volumetry Nil Excellent but global Good, global Doubtful Nil Not very handy
INVASIVE
Ambulatory blood pressure Nil Excellent, global Excellent Doubtful Nil Invasive
Arm–foot pressure gradient Nil Nil Nil Excellent at
Ascending venogram Good, false
Descending venogram Good Excellent Nil Good Good Invasive, requires
Endovenous ultrasound Nil Nil Nil Excellent Excellent Invasive, not
Nil Nil Nil Modest correlation Nil Obsolete
Nil Nil Good Good Invasive
negatives
Calf Muscle
Pump
Not applicable Excellent, except
Good Doubtful Nil Nil
Venous
Obstruction
iliac veins
femoro-iliac level
Venous Wall
Lesions Drawbacks
Excellent Nil
everywhere
Nil Invasive
femoral venous
access
easily available
Table 5.9 Relevance of investigations according to considered
abnormalities – associated investigations
Basics Optionals
Level 1 Interrogation, medical history
Physical examination, CEAP grading
Level 2 Color duplex scan
Photoplethysmography or air
plethysmography
Level 3 Ascending venogram
Descending venogram
Ambulatory venous blood pressure
Arm–foot pressure gradient
Examination of deep veins
Duplex ultrasound is the standard for examination of deep
veins of the leg. A reflux duration of at least 0.5 seconds after
the release of calf compression identifies valvular insuffi-
58
ciency.
tion on the state of the deep venous valves. Although its
invasiveness, associated risks, and pain make it a much less
attractive option for routine use, occasionally it provides
information unobtainable with other studies (Fig. 5.41).
Photoplethysmography detects the presence of valvular in sufficiency, and compression of the superficial veins (either
manually or with a tourniquet) allows differentiation between
superficial and deep venous reflux; however, PPG cannot
localize the reflux to the level within the deep system (femoral
versus popliteal, etc.). When both superficial and deep venous
reflux are present, PPG will allow the determination of the
110
Descending venography provides accurate informa-
Continuous-wave
Doppler
Superficial
tourniquets test
Endovenous
ultrasound
relative importance of each segment. Although ascending
venography was once considered the gold standard for the
diagnosis of acute or chronic deep venous obstructive disease,
most institutions now use B-mode ultrasound or color duplex
scanning in everyday clinical practice. Magnetic resonance
venography may find a place in the diagnostic armamentarium as well, since it has been found to be as accurate as duplex
scanning in the diagnosis of DVT.
148
Descending venography detects deep venous valvular reflux
but, again, the duplex scanner offers the additional advantage
of quantifying the reflux by determining flow velocities. The
finding of deep venous valvular insufficiency is worrisome
because it may be associated with chronic venous obstructive
disease, which may give rise to venous claudication,
42–44
since there are a small number of patients who rely on their
dilated superficial channels for venous return. This has been
determined using strain gauge plethysmography
149
and most
likely may be assessed with PPG as well. Impairment of
VRT with the tourniquet might caution the examiner to avoid
treatment. Alternatively, the simplest and most practical test
is to place a 30- to 40-mmHg compression stocking on
the patient for 24 hours. The development of pain while
walking contraindicates sclerotherapy and suggests the need
for a venous bypass procedure. Using APG, Spence et al
150
found that compression therapy in patients with venous
claudication caused a deterioration in the EF and/or AVP as
measured by RVF. Noninvasive tests do not provide sufficient
sensitivity if there is genuine concern about venous claudication. The examiner must proceed with invasive pressure
measurements, such as the arm–foot vein pressure differential or the foot vein pressure elevation after reactive hyperemia, as described by Shami et al.
10
Deep venous valvular
insufficiency has also been found to reduce the likelihood
of successful long-term sclerosis of the main saphenous
64
trunk.
Table 5.10 Relevance of investigations according to considered abnormalities – critical values
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Measure Critical Value Significance
Color duplex scan Reflux duration Less than 0.5–1 s Normal valve closure time
Psathakis’ venous reflux index Less than 0.40 No reflux
Photoplethysmography Venous refilling time after exercise (VRT) More than 20 s Normal venous function
Air plethysmography Venous filling index ?
90% VRT More than 20 s Normal venous function
Ambulatory venous blood pressure Maximum More than 40 mmHg Associated with grades C5 and C6
VRT More than 20 s Normal venous function
Arm–foot pressure gradient At rest Less than 4 mmHg No obstruction
Hyperemia Less than 6 mmHg No obstruction
Table 5.11 Preferred methods of evaluation
Preferred Method Pitfalls Additional Methods
Use of Noninvasive Techniques
Deep veins Doppler ultrasound Differentiation SFJ vs CFV, SPJ vs
popliteal vein
Saphenous trunks Doppler ultrasound Same as above Percussion
Tributaries of saphenous trunks Doppler ultrasound Percussion
Perforating veins
Contribution of superficial vs deep reflux PPG/LRR AVP
Functional evaluation PPG/LRR AVP
Vulvar varices Clinical exam for SSV reflux Varicography
AVP, ambulatory venous pressure; CFV, common femoral vein; LRR, light reflection rheography; PPG, photoplethysmography; SFJ, saphenofemoral junction;
SPJ, saphenopopliteal junction; SSV, small saphenous vein.
Examination of saphenous vein trunks
Duplex ultrasound is now the standard for examination of
saphenous vein trunks. Historically, Thomas and Bowles
found that Doppler ultrasound grossly overdiagnosed incompetence when compared with venography, and they recommended that all GSV be examined with venography before
ligation and stripping. One reason for this is the fact that
Doppler examination is ‘blind’; thus, dilated tributaries of the
saphenous vein or pelvic varicosities may be mistaken easily
for the GSV. This was addressed in two early studies that compared the results of continuous-wave Doppler examination
with those obtained with duplex scanning.
found that in the examination of the GSV, Doppler was no
better than 77% sensitive and 83% specific compared with the
duplex scan. In a more recent study using duplex scanners
with even greater sensitivities, DePalma et al
tivity of 48%, specificity of 83%, positive predictive value of
83%, and negative predictive value of 44% in the determina-
Clinical exam + Doppler
66,67
The researchers
152
found a sensi-
tion of GSV reflux. By obtaining duplex scans preoperatively,
10 limbs out of 80 were spared GSV stripping.
151
On the basis of these data, it might be argued that all
patients with GSV varicosity should undergo duplex scanning
before treatment. However, the cost of this testing is high, and
the equipment is not readily available to many clinicians.
Therefore, at this time, Doppler examination offers the physician the most practical approach to this important segment of
the venous system and the duplex scan certainly may be
obtained if there is any doubt about the diagnosis.
The Doppler examination of the junction of the saphenous
trunks with the deep veins (SFJ and SPJ), and the distinction
between reflux through these junctions versus reflux through
the deep veins themselves, is often difficult and a common
source of error. In fact, studies using Doppler ultrasound have
quoted an incidence of deep venous valvular reflux from 5%
to 30%,
by the difficulty of the examination and not solely by differences between the populations examined. The distinction
50–80% accurate Venography
27,28,64
a range that is most likely partially determined
PPG/LRR
Venography
Duplex
Trendelenburg
Venography
Duplex
Duplex
Duplex
Thermography
Fluorescein
Duplex velocities
Foot volumetry
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Chapter
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5
Noninvasive Examination of the Patient Before Sclerotherapy
A
Figure 5.41 A, This 36-year-old man with recurrent venous ulcers was noted to have numerous large varices in the anteromedial thigh. A duplex scan was
complicated because of the large number of veins. B, Descending venography successfully shows an absent or occluded segment of the common femoral
and superficial femoral veins with a large number of collateral veins around the obstruction.
between junctional and actual deep venous reflux is important
for several reasons. First, Schultz-Ehrenburg
patients with deep venous valvular incompetence fared far
better with a surgical approach to their disease than with treatment that was limited to sclerotherapy. Thus, the accuracy of
this portion of the examination has a direct application to the
treatment plan. In addition, patients with deep venous valvular insufficiency should be questioned regarding a history of
iliofemoral thrombosis and possible chronic venous obstructive disease, which might contraindicate treatment of their
GSV. Finally, it is possible to have only deep venous valvular
insufficiency with a normally functioning saphenous vein.
Thus, without this differentiation, a patient may be sent for
treatment of a normal superficial vein. The technique of examination is quite simple. The Doppler probe may be placed over
the site of the SFJ or over the femoral vein with the patient
standing or supine, and the patient is asked to perform the
Valsalva maneuver. The procedure is then repeated with the
GSV firmly compressed below the Doppler probe. If reflux still
can be heard after compression is applied, the examiner
assumes that the reflux is in the femoral vein. In contrast, if
the reflux is obliterated with this maneuver, the retrograde
flow is only through the SFJ and not through the femoral vein
itself.
B
28,64
found that
the GSV or SSV is percussed with the other hand (or vice
versa). The palpation of an impulse with percussion of a particular trunk localizes the origin of the tributary to that trunk.
Alternatively, a modified Trendelenburg test supplies this
information. The patient is asked to lie down with the leg
elevated to nearly 90 degrees. The proximal GSV or SSV is then
firmly compressed, and the patient is asked to stand. If the
varicose tributary remains empty and fills only when the compression is released from the GSV, the origin of the tributary
is localized to that system. The presence of reflux from the
deep system may then be discovered by using the cough test,
in which the palpation of an impulse over the tributary when
the patient coughs implies reflux of blood from the deep
system through incompetent valves into the tributary.
As mentioned previously, although the Trendelenburg test
is reasonably accurate, the cough and percussion tests are now
considered confirmatory because the Doppler provides a more
accurate answer to these questions. Placement of the Doppler
probe over the tributary while intermittently compressing or
percussing either the GSV or SSV allows determination of the
origin of the tributary (Fig. 5.42). Listening for reflux while the
patient coughs or performs the Valsalva maneuver uncovers
connections to the deep system (since there should be no
reflux unless there is a pathway directly to the deep vein that
is unobstructed by incompetent valves). The applicability of
Examination of tributaries of the
saphenous trunks
Duplex ultrasound is now the standard for examination of
tributaries of saphenous vein trunks. The examination of the
tributaries of the saphenous trunks focuses on two major
questions: (1) to which saphenous trunk does the tributary
belong, and (2) is there reflux of blood from the deep vein
directly into the tributary? Both answers may be obtained
either by physical examination maneuvers or the Doppler or,
most definitively, with duplex ultrasound. The origin of any
tributary may be assessed with the percussion test, in which
the palpating hand is placed gently over the tributary while
112
the first piece of information is obvious. Careful evaluation
must then be directed to that particular incompetent saphenous trunk to achieve sclerosis of the tributary as well. However,
the connection of the tributary to the deep system must be
explored further because the exact route that the blood has
taken from the deep to the superficial system must be defined.
If the connection is simply through the SFJ or SPJ, again the
treatment directive is apparent. On the other hand, if the connection is actually through a perforating vein or another tribu-
64
tary,
treatment must be aimed at that particular vein and,
perhaps, treatment of the saphenous trunk may be unnecessary. Manual occlusion of the involved saphenous trunk at its
proximal end, followed by repeat examination, offers this
A
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B
Figure 5.42 The origin of a particular varicosity may be defined by listening over the dilated vein while alternately compressing the, great saphenous vein
(A) and, small saphenous vein trunks (B).
Use of Noninvasive Techniques
important differentiation. If this occlusion causes the obliteration of reflux with the cough or Valsalva maneuver then the
blood must have flowed through the SFJ or SPJ. If, on the
other hand, this maneuver does not change the result of
the test then the saphenous trunk is an important conduit
and the perforating vein must be the important route.
The importance of duplex scanning in patients with varicose disease has been verified by studies in which clinical
examination, duplex ultrasound, and plethysmography have
been compared.
153
These studies have revealed that quantitative plethysmography was not particularly helpful because
of its nonspecificity. The duplex scan, however, was able
to identify patients without SFJ reflux and could ascribe
varicosities to tributary incompetence. Such incompetence
would be the target for sclerotherapy or isolated ambulatory
phlebectomy.
Examination of perforating veins
The perforator segment of the venous system is probably the
most mysterious because of its variability, the difficulty of
locating perforators even under direct visualization in the
operating room, and the overwhelming importance ascribed
to perforating veins in the development of varicose veins and
the skin changes associated with chronic venous insuffi-
154
ciency.
about what constitutes the best method for examination of
perforating veins and their valvular competence. Nearly every
technique, including venography, Doppler, duplex, thermography, fluorescein injection, and physical examination of
fascial defects, has been used with varying degrees of success.
Complicating the evaluation of each method is the fact that
all are compared with later surgical findings, which most likely
also miss many IPVs and which are impossible to standardize.
Underscoring the current difficulties in this aspect of venous
diagnosis are data that show that the number of IPVs detected
per limb, in studies of the various diagnostic methods ranges
from 1 to 4, whereas anatomic studies have shown a range of
1 to 14, with an average of 7.
test the exact sensitivity and accuracy of each method. At best,
It is no wonder, therefore, that no consensus exists
32
Thus it is still impossible to
the examiner may miss a great deal of important pathology.
In spite of the pitfalls and limitations of current diagnostic
methods, examination for IPVs is crucial and usually productive. As mentioned previously, in a study of 901 limbs with
varicose veins, 90% were found to have incompetent perfora-
32
tors.
Of interest, only 9% of the perforators were found in
the thigh. Thigh perforators may be either single or multiple
and may occur anywhere from just proximal to the patella to
just below the SFJ, with most being single and located in the
middle third of the thigh.
in the lower leg, Dodd
155
In evaluating patients with IPVs
156
found that 45% were associated with
incompetence of the GSV, 15% with incompetence of the SSV,
and 2% with an IPV in Hunter’s canal. Therefore, any patient
with significant truncal varicosities, as well as those with signs
of chronic venous insufficiency, should undergo evaluation
for perforator valvular insufficiency.
Historically, the most important and probably the most
commonly used technique for detection of outward flow
through perforating veins was that of clinical examination. With
its ability to detect 50% to 70% of IPVs, clinical examination
should be the first step in the evaluation. Other techniques
have been studied extensively, such as thermography,
fluorescein injection,
159,160
and ascending
36,37,159
36,39,157,158
and intraosseus39 venography, generally demonstrating accuracies of
between 60% and 90%. Unfortunately, the required instrumentation makes these techniques impractical for most practitioners. The techniques can be used, however, when
perforator disease is strongly suspected but has escaped localization by other methods.
Ultrasound technology can be helpful and is associated
with greater ease and lower risks than the other methods.
Probably the most effective method of locating perforator
veins is to inject a low concentration of foamed detergent
sclerosant and follow its flow into perforating veins. Doppler
evaluation of perforator incompetence provides a diagnostic
accuracy of 60% to 90%
with experience. In one study of 39 legs,
37,80,82,160
and definitely improves
37
its accuracy
improved from 60% to 87% when it was combined with clinical examination, thus making this combination of techniques
well suited for routine clinical practice. Duplex scans are
113
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