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212 Chapter 22/Sclerosants in Microfoam: A New Approach in Angiology
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treated vein. Subfascial localization, distant from the skin
and from saphenous veins in the thigh, favors a posttreatment course with moderate or few infl ammatory symptoms. However, proximity of the skin to dilated superfi cial
varicose veins can produce undesirable clinical symptoms
and increase the risk of pigmentation.
Voluminous superfi cial varicose veins must be treated at
a lower concentration and always after the size has reduced
suffi ciently after the closure of the segment proximal to it.
The aim of this “proximal sclerosis” is not the stable closure
of the saphenofemoral junction or of the proximal source of
refl ux but rather the involution of distal varicose veins.
The aim is to reduce the size of these veins as much as
possible so that they can be treated effectively at minimal
concentrations at the next treatment session. In our view,
until there is a resolution of the problems of circumferential compression (see later), this is the most appropriate
procedure.
The stable occlusion of the saphenofemoral junction was
an objective during the early years of microfoam sclerotherapy. To mimic surgical ligation and resection of the
saphenofemoral junction, we aimed to close the junction at
the common femoral vein, monitoring its progression toward
fi brosis and resorption. Nowadays, we pay little attention to
the junction, which remains patent, with no refl ux in any
patient and with no change in the excellent long-term outcomes. This is similar to experience with VNUS Closure©
and EVLT.
FIGURE 22.3 Involution of superfi cial tributary varicosities around 15
days after closure of only the proximal segment.
POST-TREATMENT EVOLUTION—
PROXIMAL SCLEROSIS
After the refl ex vasospasm, and when the patient leaves
the clinic, the blood returns to fi ll the vessel and form a
thrombus whose size depends on the dimensions of the
INTRAVASCULAR EFFECT OF
CIRCUMFERENTIAL COMPRESSION
Direct observation using ultrasound has shown that compression stockings of 35 mm Hg have no noticeable effect
on the morphology or function of large varicose veins. Since
the vein preserves its dimensions, there is nothing to prevent
the formation of a thrombus. Even when rolls of gauze or
other nonelastic cylinders are placed on the varicose vein
and strongly compressed by a bandage of little elasticity
(Peha-Haft®; Hartmann), no reduction in the diameter of
trunk varicose veins is produced on standing. Thus, the joint
application of these compressive measures (i.e., stocking +
bandage + nonelastic cylinders) does not occlude the lumen
of the vessel.
SELECTIVE COMPRESSION
In order to overcome the ineffi cacy of circumferential
compression on varicose trunk veins in leg, we have developed a device made of fl exible inelastic fabric interwoven
with two bands of little elasticity. It can be fi tted to legs of
different diameters using a Velcro®-type fastener, and it
Safety Measures in Microfoam Sclerotherapy 213
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FIGURE 22.4 This device is made of fl exible inelastic fabric interwoven with two bands of little elasticity. It contains
an infl atable component equipped with a valve. The positional stability of the unit is essential to its effectiveness.
Transient vessel occlusion is ineffective.
contains an infl atable component of asymmetric deformability equipped with a valve (see Figure 22.4). It can be
used to apply selective pressure to the treated vein. The
minimum pressure required to keep the vessels empty is
regulated by means of a manometer.
This device is kept in place for around 10 days, until
completion of the wound-healing and fi brosis produced by
the original action of the sclerosant in the vein. A selective
apparatus of this type must be stable, applying a consistent pressure and not shifting its position on the leg (see
Figure 22.5).
SAFETY MEASURES IN
MICROFOAM SCLEROTHERAPY
The Closed-door Maneuver
The most feared complications of sclerotherapy are
intraarterial injection and deep vein thrombosis. The use of
color duplex ultrasonography helps to avoid intraarterial
injection, and injection of the Great Saphenous at the
thigh rules out a possible injection of the femoral artery. At
other sites, the use of ultrasound-guided injection and the
excellent reports on this issue have reduced the incidence
of this complication, although the clinician must always
be alert to this danger. Routine is a poor companion in
sclerotherapy.
In the sclerotherapy of varicose trunk veins, deep vein
thrombosis usually is produced by a coagulation disorder in
the patient or by an error in the administration technique (see
Figure 22.6). The most frequent site for this complication is
in leg muscle veins. However, in our experience treating
over 10,000 Great Saphenous veins with microfoam sclerotherapy, we have observed no occlusion of the common
femoral vein. Its high fl ow dilutes the sclerosant and reduces
the impact of failures of technique, such as the injection of
high concentrations or excessive volumes of microfoam for
the size of vessel treated. Nevertheless, at the start of our
experience, when the technique was not fully developed,
we performed slow injections, letting the microfoam pass
through the Great Saphenous vein without taking advantage
of the mechanical action of the pneumatic piston. At that
time, we observed several thromboses in the common
femoral caused by bubbles that fl oated on the blood with the
patient in supine position. These passed to the femoral vein
in “Indian fi le” still loaded with sclerosant, contacting its
upper epithelial wall. The limited extent of this thrombosis
and its subocclusive nature ensured its rapid lysis in the very
few patients with this complication.
The potentially most controversial points in sclerotherapy
of the saphenous refl ux are perforating veins with direct
connection to the DVS: femoral, popliteal, and medial gastrocnemius veins (see Figure 22.7).
The very common type of reinjection carries a high risk
of extending the thrombosis of the varicose vein to a more
214 Chapter 22/Sclerosants in Microfoam: A New Approach in Angiology
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FIGURE 22.5 Patient after a few days of treatment with the compression device. The positional stability on thigh
was good but the compression intensity was inadequate.
FIGURE 22.6 A partially occlusive thrombosis of common femoral vein
caused by an error in technique.
FIGURE 22.7 Perforating veins to the femoral vein carry an increased
risk of deep venous thrombosis, and the insertion of the cannula must be
carefully controlled to avoid their direct injection.
Safety Measures in Microfoam Sclerotherapy 215
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FIGURE 22.8 Passage of microbubbles to the femoral vein during injec-
tion of saphenous vein. This situation requires careful duplex monitoring
and clearance of the foam particles by foot fl exion and extension.
FIGURE 22.9 Perforating veins to the popliteal fossa must be treated
while there is compression at the connection point to minimize the volume
of foam drained into the deep venous system. Varicose vein leading to
medial gastrocnemius vein. Nothing prevents the injected sclerosant from
exerting its action a little beyond the desired segment.
or less extensive segment of the gastrocnemius vein, which
would result in thrombosis of the deep venous system, with
the possibility of it spreading proximally to popliteal and
superfi cial femoral veins.
We take two precautionary measures to avoid this undesirable action. The fi rst is a dual measure: a reduction in
the concentration of sclerosant and a strict limitation of the
injected volume to the capacity of the vein to be treated (see
Figure 22.8). Injections that exceed this volume and concentrations greater than 0.37% are errors of technique.
The second measure is to close the gastrocnemius vein
during and after the injection by taking advantage of the
muscle function. We fi rst confi rm by ultrasound that these
muscle veins are completely closed when the patient is
FIGURE 22.10 Color duplex ultrasonography is used to confi rm that
dorsal fl exion of the foot closes the intramuscular venous segment.
standing and that they remain so while the muscle contraction caused by this position persists, with complete closure
of the lumen. In supine position, active dorsal fl exion of the
foot produces a similar result. If the patient tires, closure by
the muscles can be achieved by passive fl exion, using the
hand of clinician or assistant to exert dorsal pressure on
the foot (see Figure 22.9). Active, voluntary contraction
of the muscles is more effective, although many patients do
not have this ability and must be taught it.
We routinely use dorsal fl exion during the injection of
any varicose leg vein, checking its effectiveness on ultrasound. If it is not effective, another technique is used
(see Figure 22.10).
We also use these novel “closed door” maneuvers during
the sclerosis of low perforating veins as a complementary
216 Chapter 22/Sclerosants in Microfoam: A New Approach in Angiology
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TABLE 22.1 Compression Requirements of Large Superfi cial
Varicose Veins
Selective
Controllable (with capacity to occlude the vein)
Stable pressure values and position on leg
TABLE 22.2 Measures to Insure Effi cacy and Safety
Previous proximal sclerosis
Appropriate concentration of sclerosant
Precise injected volume
Closed-door maneuver
Selective compression of dilated superfi cial varicose veins
TABLE 22.3 Treatment Strategy
1˚ Elimination of existing varicose veins
FIGURE 22.11 Voluminous and complex varicose veins before and
after treatment.
2˚ Elimination of varicose heritage
One-year active follow-up equals stable outcomes
measure to the exertion of pressure on the perforating vein
itself with fi nger or ultrasound probe. We must be 100% sure
that the sclerosant does not reach the deep venous system in
an uncontrolled manner. This combination of safety measures that we have gradually developed and applied in our
daily practice has led to a progressive reduction in any complications of this nature.
In our long experience, we have had 22 cases of deep
venous thrombosis of leg muscle veins in more than 10,000
patients. In 10 patients, a coagulation disorder was the cause.
After the use of these maneuvers we have not observed DVT
of muscular veins.
The effi cacy of sclerotherapy with microfoam is now
beyond doubt. It achieves the elimination of all varicose
veins in all patients, with no limitations on the extent, size,
site, or morphology of the vessels that can be treated by this
method.
The effective safety measures that we have introduced
make it the therapeutic approach of choice when the anatomical and functional removal of large and complex pathological varices is indicated (see Figure 22.11).
LONG-TERM EVOLUTION—
STABILITY OF OUTCOMES
Our fi nal objective is to make these optimal outcomes
stable over the long-term. The Achilles’ heel of surgery is
the high recurrence rate of varicose veins.
limitation of the surgical approach along with the aggressive
nature of surgery and its incomplete outcomes.
18,19
This is a major
TABLE 22.4 Future Perspectives
Pharmaceutical grade microfoam
Standard technique
We must warn you that varicose veins often can reappear
in legs that were treated only a few months earlier, even
when all varicose veins were successfully removed. These
recurrences seem to be caused by the development of varicose veins that were not visible at the time of treatment but
were nevertheless part of the varicose heritage of the patient.
These incompetent veins take the place of those that are
removed, maintaining hemodynamic continuity to the endvessels in leg muscles and ensuring their progression.
Besides sclerotherapy with microfoam, we know of no
therapeutic procedure that can remove all types of varicose
veins. However, the disappearance of all varicose veins from
a given area does not mean that total success has been
achieved. Final victory can be claimed only when we can
be reasonably sure that we have also eliminated all veins
that may constitute a source of recurrence. To this end, an
exhaustive color duplex ultrasound study is made at the
second treatment session (at 3 to 5 months) and we treat all
varicose veins revealed in the leg. Newly formed varicose
veins are also identifi ed and treated during follow-up
sessions at six, nine, and 12 months. This active follow-up
approach achieves the progressive, systematic, and complete
References 217
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removal of varicose veins that could produce a recurrence
and whose suppression is the key to long-term stability
of outcomes. These goals cannot be attained by surgery or
endoluminal techniques when used alone.
Varicose disease is considered an essentially progressive
condition. Nevertheless, application of the correct treatment
can markedly reduce the recurrence rate.
Our current working objectives are to continue to improve
the technique, accelerating the treatment and making it more
comfortable for the patient. The type of compression applied
is of critical importance for comfort. Since we have observed
no benefi ts from the application of a strong compression, we
use high-quality stockings that exert moderate compression.
These Mediven®plus stockings have been well accepted by
patients.
The availability of a micronized, homogeneous, and
reproducible foam of pharmaceutical grade is crucial,
because it would allow us to develop a standard treatment
protocol, allowing outcomes obtained by different groups to
be compared.
References
1. Mollard JM. Chronic venous insuffi ciency: Prevention and drugless
therapy, Presse Med. 1994. Feb 10;23(5): 251–258. Review.
2. Hsu TS, Weiss RA. Foam sclerotherapy: A new era, Arch Dermatol.
2003. 139: 1494–1496.
3. Cabrera J, Cabrera J Jr. Nueva método de esclerosis en las varices
tronculares, Patol Vasc. 1995. 4: 55–73.
4. Cabrera Garrido J. Élargissement des limites de la sclérothérapie:
Nouveaux produits sclérosants, Phlébologie. 1997. 50: 181–188.
5. Cabrera Garrido J. Los esclerosantes Enclosure microespuma contra
la patología venosa, Noticias Méd. 1997. 3:653: 12–16.
6. Cabrera J, Cabrera J Jr, Garcia-Olmedo A. Treatment of varicose long
saphenous veins with sclerosant in microfoam form: Long-term outcomes, Phlebology. 2000. 15: 19–23.
7. Cabrera J, J Cabrera J Jr, García-Olmedo A, Redondo P. Treatment
of venous malformations with sclerosant in microfoam form, Arch
Dermatol. 2003. 139: 1409–1416.
8. Cabrera J, Redondo P, Becerra A, Garrido C, Cabrera J Jr, GarciaOlmedo MA et al. Ultrasound-guided injection of polidocanol microfoam in the management of venous leg ulcers, Arch. Dermatol. 2004.
140: 667–673.
9. Bergan JJ, Pascarella L. Severe chronic venous insuffi ciency: Primary
treatment with sclerofoam, Semin Vasc Surg. 2005. 18: 49–56.
10. Monfreaux A. Traitement sclerosant des troncs saphenies et leurs
collaterales de gros calibre par la methode MUS, Phlébologie. 1997.
50(3): 351.
11. Henriet JP. Three years’ experience with polidocanol foam in treatment
of reticular veins and varicosities, Phlébologie. 1999. 52: 277.
12. Benigni JP, Sadoun S, Thirion V et al. Telangiectasias et varices
reticulaires: Traitement par la mousse d’Aetoxisclerol a 0.25 Presentation d’une etude pilote, Phlébologie. 1999. 3: 283–288.
13. Tessari L, Cavezzi A, Frullini A. Preliminary experience with a new
sclerosing foam in the treatment of varicose veins, Dermatol Surg.
2001. 27: 58–60.
14. Wollmann JC. The history of sclerosing foams, Dermatologic Surgery.
2004. 30: 694–703.
15. Breu FX, Guggenbichler S. European consensus meeting on foam
sclerotherapy, April, 4–6, 2003, Tegernsee, Germany, Dermatol Surg.
2004. 30: 709–717.
16. García Mingo J. Foam medical system, a new technique to treat varicose veins with foam. In: Foam sclerotherapy state of the art, Editions
Phlebologiques Francaises 46 rue SaintLambert Paris. 2002. ISBN285480-958-0. 45–50.
Mingo-Garcia J. Esclerosis venosa con espuma, Rev Esp Med Cir
Cosmetica 1999; 7: 29.
17. Cabrera J Jr, Garcia-Olmedo MA, Dominguez JM, Mirasol JA. Microfoam a novel pharmaceutical dosage form for sclerosants. In: Foam
sclerotherapy state of the art, Editions Phlebologiques Francaises 46
rue SaintLambert Paris. 2002. 17–20.
18. Fischer R, Linde N, Duff C, Jeanneret C, Chandler JG, Seeber P. Late
recurrent saphenofemoral junction refl ux after ligation and stripping of
the greater saphenous vein, J Vasc Surg. 2001. 34: 236–240.
19. Stonebridge PA, Chalmers N, Beggs I. Recurrent varicose veins: A
varicographic analysis leading to a new practical classifi cation, Br J
Surg. 1995. 82: 60.
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CHAPTER
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23
Ultrasound-Guided Catheter and Foam Therapy
for Venous Insuffi ciency
LUIGI PASCARELLA and JOHN J. BERGAN
INTRODUCTION
Duplex ultrasound sonography represents the best method
of evaluation of venous refl ux in the lower extremities.1 This
test is noninvasive, generally acceptable to the patient, and
inexpensive.2 It provides direct imaging, localization, and
extent of venous refl ux with a surprisingly high sensitivity
(95%) and specifi city (100%).3 Duplex ultrasound fi ndings
have also been confi rmed with angioscopic observations of
incompetent vein valves in advanced chronic venous insuffi ciency.4 As demonstrated by Yamaki, high peak refl ux
velocities (>30 cm/s), refl ux duration greater than three
seconds, and an enlarged valve annulus measured by duplex
ultrasonography at the SFJ are closely related to angioscopically deformed and incompetent terminal valves (Type
III and Type IV valves of Hoshino).
4
PRETREATMENT ASSESSMENT
The examination should always begin with a complete
medical history. Data concerning family and personal venous
history, symptoms, clinical fi ndings, and previous venous
treatments are collected. Comorbidities, allergies, and pharmacologic history must be documented.2 The BMI is calculated from the patient’s height and weight and should be
recorded.
The patient should be examined in a standing position
to demonstrate patterns of teleangiectasias, reticular veins,
and varicose veins.5 Cold light transillumination of the skin
(vein light) may be used to identify reticular veins, and a
handheld Doppler device can verify the presence of refl ux
in some superfi cial veins as a screening examination.5 Thus
the three levels of pathologic veins are evaluated. Telangiectasias in the skin are visually inspected, reticular veins are
transilluminated with the vein light, and varicosities and the
saphenous veins are examined with ultrasound. Clinical data
should be integrated into the CEAP classifi cation.
6,7
EQUIPMENT
The ultrasound duplex scanner should be able to detect
blood fl ow rates as low as 6 cm/sec.2 This can be done by
dedicated high resolution vascular scanners with color and/
or power-Doppler functions as well as the pulsed wave
Doppler. Linear transducers in the range of 4–7 megahertz
are used.
veins of the limbs in obese patients may be imaged with 3
megahertz transducers.
the range of 5–12 Mhz can provide a detailed imaging of
smaller veins and perforating veins.
become smaller, more transportable, and more operator
friendly.5 Miniaturized devices feature transducers designed
with advanced architecture that allow a single probe to
image across a greater range of depths within an application
and across applications.5 The transducer for peripheral vascular examinations operates from 10–5 MHz and provides
resolution from skin surface to 7 cm in depth.5 The technology incorporates power Doppler sonography, tissue
harmonic imaging, and direct connectivity to a personal
computer.
more traditional and much larger ultrasound equipment.
5,8
The inferior vena cava, pelvic veins, and deep
1
Linear hockey-stick transducers in
With the advances in technology, duplex scanners have
5
Their overall performance is comparable to the
5
The Vein Book
219
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Copyright © 2006, Elsevier Inc.
220 Chapter 23/Ultrasound-Guided Catheter and Foam Therapy for Venous Insuffi ciency
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FIGURE 23.1 This data entry form outlines the saphenous veins and the relevant deep veins. Refl uxing veins are
added in heavy black lines. Location of perforating veins and aneurysms can be added and distance from the fl oor
indicated. Diameters of perforating veins at the fascial level should also be noted.
VENOUS REFLUX EXAMINATION
AND VENOUS MAPPING
A detailed US duplex study of the normal and pathologic
venous anatomy (refl ux) is essential. A clear graphic notation (mapping) of signifi cant vein diameters, anomalous
anatomy, superfi cial venous aneurysms, perforating veins,
presence and extent of refl ux should always be recorded
during the examination (see Figure 23.1).
The ultrasound examination is conducted with the patient
standing.9 This position has been found to dilate leg veins
maximally and challenges vein valves. Sensitivity and
specifi city in detecting refl ux are increased in examinations
performed with the patient standing rather than when the
patient is supine.
8,9
Supine examinations for refl ux are
unacceptable.
The veins are scanned by moving the probe vertically up
and down along their course. Duplicated segments, sites of
tributary confl uence, and large perforating veins and their
deep venous connections are identifi ed. Their location measured in centimeters from the fl oor provides a therapeutic
guide. Measurements from the medial malleolus are not as
precise. Transverse and longitudinal scans combined with
continuous scanning are performed in order to provide a
clear mapping of the venous system. Patency usually is
assessed by compression of the vein with the transducer.8
Refl ux is detected by fl ow augmentation maneuvers such as
2,5
distal compression and release of the thigh and calf or the
Valsalva maneuver for only the saphenofemoral junction.
8
Automated rapid infl ation/defl ation cuffs are cumbersome
but may be used for this purpose and offer the advantage of
a standardized stimulus.
considered pathologic.
10–12
Refl ux greater than 500 ms is
9,13
The diameter of the saphenofemoral junction and femoral
vein are recorded for use in judgment for radio frequency
VNUS closure© and endovenous laser EVLT treatments.
14–16
Important information also is offered by the diameters of the
GSV at mid thigh and distal thigh. Radiofrequency ablation
commonly is applied to treat veins from 2–12 mm in diameter.16 The supragenicular, infragenicular, or immediate
subgenicular Great Saphenous vein is often the access point
for its laser or radiofrequency ablation.
16,17
Therefore the
depth of the GSV in these regions is additional data to be
recorded.
Accessory veins by defi nition run parallel to the GSV in
the thigh (see Figure 23.1).18 It is imperative to map their
course accurately and to note their eventual communication
with GSV (see Figure 23.1). They are easily confused with
the GSV, especially during continuous longitudinal scanning when the saphenous vein appears to leave the saphenous compartment.
18
The Great Saphenous vein is then scanned in the leg and
the thigh so that tributaries to the GSV should be noted (see
Figure 23.1).
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The diameters of the popliteal vein and the Small Saphenous vein (SSV) are recorded, as well as diameters of the
SSV along its course in the leg. Intersaphenous veins should
also be identifi ed and the variability in SSV termination
carefully recorded.
The venous refl ux examination also includes the mapping
of exit and reentry perforating veins (PV).19 PV refl ux is
detected as outward fl ow duration greater than 350 ms on
the release phase of fl ow augmentation maneuver (distal
compression has higher sensitivity in detecting PVs refl ux).1
Perforating veins should be accurately located in their different locations in the leg. Their position should be measured as distance (cm) from the fl oor in the extended
18,20
limb.
FIGURE 23.2 The Great Saphenous vein is cannulated using the Seld-
inger technique. The puncturing needle is echogenic and can be easily
ULTRASOUND MONITORING
DURING EVLT AND VNUS
CLOSURE
©
OF THE GSV AND SSV
visualized. (Adapted from Pichot O, Atlas of Ultrasound Images, Copyright
VNUS® Closure)
Thermic coagulation is caused by the application of electromagnetic energy to the endothelial surface of targeted
16,21,22
veins.
It has been suggested that the coagulation process
in laser treatment is related to the intravascular vaporization
of blood (steam) with intimal denudation and collagen fi ber
contraction. Vein wall thickening and rapid reorganization
of the vessel to form a fi brotic cord follow.
21,22
Occlusion
usually is visualized within 10 to 20 seconds from the laser
or radiofrequency energy application.22 These techniques
have been proven to be safe and effective.23 Percutaneous
introduction of the laser or RF catheter has made formerly
extremely invasive therapy (SFJ ligation and GSV stripping)
more acceptable to the patient in terms of post treatment
pain, number of cutaneous incisions, and post-procedural
disability.
the patient for better identifi cation of the venous segment to
cannulate. In this preparatory phase some anatomic landmarks have to be clearly recognizable:
1. Femoral vein
2. Saphenofemoral junction
15,16
Before the procedure, it is always recommended to rescan
FIGURE 23.3 The laser catheter is advanced proximally toward the
saphenofemoral junction. Position of the laser fi ber is confi rmed by direct
visualization of the red aiming beam through the skin. (Adapted from
Navarro L, Min RJ, Bone’ C. Endovenous laser: A new minimally invasive
method of treatment for varicose veins: Preliminary observations using an
810 nm diode laser dermatologic surgery, Volume 27, 2:117. February
2001)
3. Saphenous compartment
4. Great Saphenous vein
5. Small Saphenous junctional anatomy
Introduction of the introducer sheath is performed percutaneously using the Seldinger Technique. The supragenicular
saphenous vein is usually the access point of choice (see
Figure 23.2).
17
The intraluminal position of the sheath is
ascertained by aspiration of nonpulsatile venous blood. The
sheathed laser fi ber or a 6 or 8 F VNUS catheter is advanced
to a point just distal to the entrance of the epigastric vein.
Position of the laser fi ber is confi rmed by direct visualization
of the red aiming beam and that of the VNUS catheter by
ultrasound (see Figures 23.3 and 23.4).
16
The catheter or sheath appear as a hyperechoic line in the
GSV lumen.
14,15
Its placement must be precisely at the SFJ
1 cm distal to the epigastric vein (see Figure 23.4).
Administration of the tumescent anesthesia into the
saphenous compartment is monitored by ultrasound.17 The
17
vein is seen as “fl oating” in an echogenic sea of the anesthetic solution (see Figure 23.5). It is always wise to recheck
16
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