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Treatment of Leg Veins
Box 9.1 Endovenous laser wavelengths, commercially
available
810 nm Diode Laser (AngioDynamics Queensbury, NY)
940 nm Diode Laser (Dornier MedTech Americas, Inc.,
Kennesaw, GA)
980 nm Diode Laser (Biolitec, Inc., East Longmeadow, MA)
1320 nm (CoolTouch, Roseville, CA)
1470 nm (Biolitec)
Box 9.2 EVTA Indications
I. Symptoms of venous insufficiency affecting quality-of-life
i. Aching
ii. Throbbing
iii. Heaviness
iv. Fatigue
v. Restlessness
vi. Night cramps
vii. Pruritis
viii. Spontaneous hemorrhage
II. Skin changes associated with chronic venous
hypertension
i. Corona phlebectasia, eczema and pigmentation
ii. Lipodermatosclerosis
iii. Atrophie Blanche
iv. Healed or active ulceration
v. Edema
vi. Superficial phlebitis (SVT) in varicose veins
III. Cosmetic (restorative) concerns
IV. Anatomical indications
i. Significant reflux documented on duplex ultrasound
(DUS) examination (reflux >0.5 seconds)
ii. Straight vein segment
iii. Intra- or epi-fascial vein segment meeting other
anatomical criteria that can be pushed away from the
skin with tumescent anesthetic
iv. Reflux responsible for venous hypertension leading to
the clinical abnormalities
V. Ambulatory patient without contraindication
EVTA has been used to treat long straight competent
tributary veins outside the superficial fascia, particularly
in patients who are obese and in whom either sclerotherapy of microphlebectomy would be difficult, time
consuming or prone to side effects.
EVTA EQUIPMENT
Equipment and supplies common to ELA and CF are
listed in Box 9.4. A foot pedal controlled pump (AngioDynamics or HK Surgical) can be used to infuse the
perisaphenous anesthetic infusion as an alternative to hand
injection. Venous access kits that allow the use of a less
traumatic 21 gauge needle to insert a 0.018 in guidewire
are useful when accessing small veins but do add expense
to the procedure. These kits include a 4 or 5F sheath with
a dilator tapered to the 0.018 in guidewire. After the
sheath and dilator are inserted the dilator and 0.018 in
guidewire can be removed to allow the placement of a
standard 0.035 in guidewire. (Cook, AngioDynamics,
Vascular Solutions or Merit Medical).
Box 9.3 Relative contraindications to EVTA
v Pregnancy or nursing female patients (concerns related to
anesthetic use and heated blood effluent which may pass
through the placenta to the fetus)
v Obstructed deep venous system inadequate to support
venous return after EVTA
v Liver dysfunction or allergy making it impossible to use a
local anesthetic (cold saline may be useful as an
alternative)
v
Allergy to both amide and ester local anesthetics (cold
saline may be an alternative)
v Severe uncorrectable coagulopathy (EVTA is anecdotally
safe with Warfarin use if INR <2)
v Severe hypercoagulabilty syndromes (where risk of
treatment outweighs potential benefits despite prophylactic
anticoagulants)
v
Inability to wear compression stockings secondary to
inadequate arterial circulation, hypersensitivity to the
compressive materials or musculoskeletal or neurological
limitations to donning the stocking itself
v Inability to adequately ambulate post-procedure
v Sciatic vein reflux
v Thrombus or synechiae in the vein or tortuous vein making
passage of an endovenous device impossible (unless
multiple access points are chosen)
Box 9.4 Equipment common to ELA and CF
v Procedure table that can tilt to Trendelenberg and reverse
Trendelenberg
v
DUS with at least a 7.5 MHz transducer
v Sterile gowns, gloves, masks, drapes, gauze
v Ultrasound gel, sterile ultrasound probe and cord cover
v Antiseptic preparation fluid
v Local anesthetic
v No. 11 or 15 scalpel blade
v 18–21 gauge needle for percutaneous entry
v 21–25 gauge needle for administration of tumescent
anesthesia
v
Syringes
v Normal saline
v Compression stockings
Additional materials required to perform ELA include
the laser generator (available from several vendors), sheath
long enough to cross the abnormal venous segment(s)
usually included in a kit along with a guidewire and sterile
laser fiber. Additional components needed for CF include
the VNUS radiofrequency generator, introducer sheath,
CF catheter and guidewire.
ELA is usually performed by placing a 4 or 5F sheath
into the vein to be treated over a 0.035 in guidewire and
then, after inserting a laser fiber into the sheath, withdrawing the sheath to expose the fiber tip. The sheaths
are manufactured in multiple lengths and generally the
sheath chosen is as long or longer than the segment(s) to
be treated. The fibers are generally bare tipped, 600
micron in diameter and are usually premarked to allow
the operator to know when the fiber is tip to tip with the
end of the sheath as well as when they extend a fixed
distance beyond the tip. In very straight veins, a laser fiber
can be advanced beyond its sheath to the starting point of
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Endovenous Thermal Ablation
Figure 9.1 Tumescent anesthetic should
be delivered in copious volumes in the
perivenous space of a vein to be treated
with EVTA. (A) The DUS axial image
demonstrates an axial US image of the GSV
before tumescent anesthetic. (B)
Demonstrates the hypoechoic halo of
tumescent anesthetic fluid after it has been
injected around the GSV
ablation, but advancement through the sheath is recommended to avoid passing the fiber through the vein wall.
An 11 cm long 7F sheath is used with the CF catheter.
The CF catheter is available to 60 cm or 100 cm lengths.
The CF catheter is 7F in diameter and after introduction
of its sheath, it can be passed into the vein over a 0.025 in
guidewire although the manufacturer has found guidewire
use is necessary in only a minority of cases. The catheters
have a resistive element at the distal 7 cm that heats to a
fixed temperature when activated. The catheters are
marked in 6.5 cm intervals to fascilitate segmental withdrawal after activation that builds in a 5 mm overlap for
each segmental treatment.
TUMESCENT ANESTHESIA
Tumescent anesthetic, when used in phlebology, describes
the use of large volumes of dilute anesthetic solutions that
are infiltrated into the perivenous space of the veins to be
treated. The rationale behind the use of large volume
tumescent anesthesia for EVTA include (a) its use as a
local anesthetic, (b) its ability to extrinsically compress
and empty the vein to maximize the contact of the thermal
device and the vein wall for efficient thermal transfer to
the vein wall as well as (c) providing a protective heat sink
around the treated vein to minimize heating of adjacent
structures.
ELA and CF is usally performed with a dilute tumescent anesthetic solution of Lidocaine in normal saline (a
concentration of 0.1% lidocaine is typically used with an
average volume of about 5–10 mL/cm of treated vein)
with or without epinephrine, often buffered with sodium
bicarbonate. This should be delivered with ultraound
guidance into the perivenous space (saphenous sheath) of
the vein to be treated. If can be injected either manually
or with an infusion pump such that upon completion of
the process the vein is surrounded along its entire treated
length with the anesthetic fluid as demonstrated in
Figure 9.1.
Although the maximum safe dosage of lidocaine using
tumescent technique for venous procedures is not well
studied, 35 mg/kg with epinephrine has been reported as
safe in the plastic surgical literature. However, one should
keep in mind the FDA reviewed circulars accompanying
units of lidocaine state a maximum does of 5 mg/kg
without and 7 mg/kg with epinephrine with each use.
EVTA TECHNIQUE
The steps common to both ELA and CF are:
1. Perform preprocedural DUS to map the venous
segments to be treated. Mark the course of the
vein(s) to be treated along with important
anatomical landmarks associated with the ablation
on the skin including the proposed venous access
site(s) and deep vein junctions. The access site is
ideally at the inferior end of the incompetent
segment or segments of the treated vein. In most
cases, the entire incompetent segment(s) can be
treated with one puncture. If microphlebectomy
will be performed along with EVTA, the veins to be
removed should be marked at this time as well.
2. Prepare the operative tray and equipment. Aside
from the thermal ablation device and a venous
access kit, only basic supplies such as gauze, a
sterilizing solution, sterile barriers, as well as the
tumescent solution, with delivery syringes and
needle and an ultraound probe cover are needed.
3. Position the patient on the procedure table to allow
visualization of the veins that need treatment. This is
generally supine but the prone position is preferred
for treatment of the SSV or Vein of Giacomini.
Elevation of the torso of the patient relative to the
legs will prolong venous distention and enhance the
likelihood of successful venous access. Carry out
sterile preparation and draping of the leg to be
treated. Pre-procedural antibiotics are not necessary
in almost all circumstances as the procedure is
performed sterilely and is considered “clean”.
4. Visualize the access site with DUS. Placing the
patient in a reverse Trendelenberg or partly sitting
position will keep the vein more distended and may
facilitate venous access.
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Treatment of Leg Veins
5. Anesthetize the access site. Nick the skin just large
enough to facilitate entry of the sheath through
the skin.
6. Insert the access needle into the GSV under
ultrasound guidance. Use of a 21G puncture set, as
discussed previously, is preferred by one author in
all cases (N.K.) and by the other author (S.Z.)
when the target vein is <
Cutdown is rarely needed and used only if
percutaneous access fails.
7. Place a 0.035 in guidewire into the vein.
8. Confirm intravenous placement with ultrasound.
9. Place the introducer sheath over the wire.
10. Fully advance the short sheath for CF. Position the
sheath for ELA to the starting point for ablation.
One author will typically advance the ELA sheath
beyond the starting point and later withdraw it with
the laser fiber to the starting spot. The movement
of withdrawal helps in accurately identifying the tip
and in positioning it at the starting point.
11. Remove the wire and its dilator if one is used with
the sheath. Check for venous return by aspirating
the syringe attached to the sheath and flush.
Recognize that the sheath tip maybe against the vein
wall and may not aspirate freely. Also realize when
flushing, micro bubbles of air introduced into the
vein may produce an acoustic shadow that may limit
the ability to see venous detail and device positions.
Additional steps for ELA include:
1. Introduce the laser fiber into the sheath so that
the fiber reaches the sheath tip. There is generally
a mark on the fiber to show this. Then fix the
laser fiber and carefully pull back the sheath to
expose about 2–3 cm of fiber. One should then
withdraw the entire sheath-laser fiber to the
ablation starting spot.
2. Fine tune the location of the tip of the laser fiber to
just below the superficial epigastric vein, AAGSV or
other large junctional vein for the GSV, and just
below the thigh extension junction (or parallel to
the skin and just beyond the segment that dives
toward the popliteal vein when a thigh extension
does not exist) with the SSV for SSV ablations (Fig.
). For closure Fast, place the device 1-2 cm
9.2
below saphenofemoral junction (SFJ) or
saphenopopliteal junction (SPJ).
3. Connect the laser fiber to its generator and confirm
that tip is in the correct general location by viewing
visible light that can be delivered into the laser fiber
tip and visualized through the skin (Fig. 9.3). This is
an additional way to ensure that the tip of the laser
is being visualized accurately and that the laser
connections were made appropriately. If the light is
not seen in the expected location the operator
should troubleshoot the position of the laser or the
connection to the laser to understand why.
4 mm in diameter.
4. Administer tumescent anesthesia with ultrasound
guidance after the patient has been placed into the
Trendelenburg position to help drain the vein.
5. Place appropriate laser safety goggles on everyone
in the procedure room and use other appropriate
laser safety measures. Connect the laser fiber to
the laser and verify proper laser settings. Setting
recommendations vary, but as will be discussed aim
to deliver at least 70–80 J/cm length of vein
treated: at 14 W this is achieved with a maximum
pullback rate of 2 mm/s.
6. Set the laser to continuous mode and select the
power to be used. Re-verify placement of the laser
tip with ultrasound (Fig. 9.4).
7. Activate the laser and withdraw the fiber and sheath
at the speed that is dependant on the amount of
energy you wish to deliver at the power setting
selected with the laser in continuous mode. One
author will deliver 70 J/cm 14 W continuous mode
at 810 nm throughout. The other author (NK) uses
more energy for the first 10 cm (140 J/cm) and less
as the laser tip progresses lower down the leg
(100 J/cm to the knee and 70 J/cm below the
knee). This is done to ensure closure vein of the
proximal, where failure occurs most, and to
decrease the risk of nerve injuries lower in the leg
(see Technical comments).
8. Stop laser energy delivery at the distal aspect of the
vein and place the laser in standby mode.
9. Remove the fiber/sheath from the vein. Be sure the
entire fiber is removed to exclude the possibility of
a fracture of the device intravascularly.
10. Record the watts, laser on-time, total joules
delivered and length of the segment treated.
Calculate the withdrawal rate and joules delivered
per cm to ensure you have reached the targets for
successful ablation.
Additional steps for ClosureFast (CF) are as follows:
1. Introduce the 7F ClosureFast catheter through its
sheath either bare or over a 0.025 in guidewire and
position its tip to the desired starting position 2 cm
below the deep junction. Connect the CF catheter to
the RF generator.
2. Deliver tumescent anesthesia and place the patient in
the Trendelenburg position as discussed previously.
3. Withdraw the sheath so that one of the 6.5 cm
marks on the catheter is located at the point the
catheter exists the sheath.
4. Activate the generator perform two 20 second
heating cycles at the preset temperature of 120°C.
Withdraw the catheter 6.5 cm and repeat the heating
cycle until the entire vein is ablated. The second
20-second cycle is recommended by the
manufacturer at the first treatment site although
some operators will perform second cycles at all
levels or selectively at levels with aneurysmal
Femoral
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vein
Great saphenous
vein
Popliteal
vein
129
Endovenous Thermal Ablation
A
Inguinal ligament
Superficial circumflex
iliac vein
Common femoral
vein
Small saphenous
vein
Superficial
epigastric vein
Anterior accessory
saphenous vein
Great saphenous
vein
B
External pudendal
vein
Posterior accessory
saphenous vein
Figure 9.2 (A) GSV and SSV. (B) Anatomy
of the right saphenofemoral junction.
Modified from a drawing by Pentti Rautio
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Treatment of Leg Veins
Figure 9.3 Aiming beam of the laser fiber tip
visible through the skin during ELA
7. Record the parameters, duration of treatment, and
length of segment treated (Fig. 9.5).
Figure 9.4 Longitudinal (sagital) ultrasound image of the
saphenofenoral junction demonstrating a 400 micron laser fiber tip in
the great saphenous vein (GSV) just below the superficial epigastric
vein (SEV). FV, femoral vein
segments or near large tributaries, such as an
incompetent perforator to ensure thorough ablation.
5. When the amount of vein left to treat is <7 cm long,
marks will be visible on the catheter to alert the
operator. The sheath should be withdrawn at this
point to allow the heating element to extend beyond
the sheath to ensure vein treatment as well as to
avoid heating the sheath or the skin. Cease treatment
when the catheter tip enters the introducer sheath or
exits the vein.
6. Remove the CF catheter and sheath after the final
ablation.
POSTOPERATIVE CARE AND INSTRUCTIONS
Postoperative care is designed to improve efficacy and
minimize side effects and the risk of complications.
Immediately postoperatively, a class II compression stockings (30–40 mmHg) is applied and worn for 1–2 weeks.
Patients should ambulate for at least 30–60 minutes after
leaving the procedure room and at least 1–2 hours daily
for 1–2 weeks. Hot baths, running, jumping, heavy lifting
and straining should be avoided for 1–2 week. Nonsteroidal anti-inflammatory drugs may be taken on an as-needed
basis for discomfort.
Patients are generally seen at one month after the procedure to assess the results by clinical exam and by DUS.
Some physicians recommend a follow-up DUS at 24–72
hours after the procedure as surveillance of junctional
thrombus extension from the treated vein into the deep
vein. However, as will be discussed later, the yield of this
early examination for identifying extension of thrombus
beyond the deep junction extending into the femoral vein
for GSV or popliteal vein for SSV ablation is at most 1%.
Moreover, treatment of such non-occlusive extensions
is controversial. Repeat DUS at about 12 months after
the procedure will ultimately determine the anatomical
success of the ablation.
TECHNICAL COMMENTS
Percutaneously accessing the vein may be the most challenging aspect of performing endovenous techniques. This
is particularly true with veins that are small, or when
accessing tributary veins, below knee segments of vein and
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Endovenous Thermal Ablation
Figure 9.5 Varicose veins (A) before and (B) 1 month after ELA of the GSV and ambulatory phlebectomy of surface varices
in anxious patients, particularly young women with Raynauds. Several tips can facilitate the successful completion
of this key maneuver. The room should be warm and the
patient made to feel as comfortable as possible. Prepping
the patient in a reverse Trendelenburg or sitting position
and making every effort to puncture the vein(s) as quickly
as possible after placing them on the table will decrease
the degree to which the vein will empty prior to puncturing. Anxious patients prone to vasospasm may benefit
from oral anxiolytics although they is rarely used in our
practices.
A 21G puncture kit can facilitate accessing veins as
mentioned. Striving to successfully puncture the vein on
the first attempt can obviate inducing vasospasm or creating a hematoma that will compress the vein. Tributary
veins, the below knee GSV and the AAGSV are more
prone to spasm with venous access than other veins. When
puncturing an AAGSV, below knee GSV or when accessing a tributary to gain access to the GSV as part of a
procedure involving introduction of sheaths into several
veins, puncture these veins first, before they have had a
chance to empty, to maximize your success. If vasospasm
does occur, options include moving proximally for vein
access or stopping and waiting for the spasm to subside.
In some cases it may be best to stop the procedure, have
the patient ambulate for 15 minutes and then try again.
Once a vein has been accessed, rapidly proceeding with
insertion of the guidewire and introducer can reduce the
risk of vasospasm. If the sheath is in the vein but venous
spasm makes sheath advancement is difficult or painful,
injecting normal saline solution through the sheath,
waiting a few minutes or injecting tumescent anesthetic
around the sheath can be helpful.
If the tip of the laser fiber or CF catheter is not visible
on ultrasound following placement, the tip may be in the
common femoral vein or within the introducer sheath.
The tip may also be obscured if the angle between the
DUS probe and the laser fiber or CF catheter becomes
too acute. Angling the DUS probe in a way to make the
US beam perpendicular with the catheter or fiber will
maximize the amount of US reflected improving visualization. Pushing down on the laser sheath or CF catheter
along its course or gently moving it in and out of the
vein will move the fiber or catheter tip also helping to
identify their tip locations. With ELA, only use the visible
light aiming beam for gross estimations of laser tip localization. The light should not substitute for definitive DUS
localizations.
Treating all incompetent venous segments responsible
for the patients clinical problem will optimize patient
clinical and cosmetic improvements. Occasionally two or
more punctures will be needed to ablate an entire incompetent vein segment, as aplastic segments, previously
occluded segments, tortuosity or thrombosis will not
allow passage of a guidewire from one puncture to all segments. In some patients, simultaneous treatment of more
than one vein segment in the same sterile field is an efficient way to accomplish this goal. In other cases, when
the vein segments are in different fields, the patient can
return for treatment of subsequent veins at a later date.
Tailoring the treatment to the severity of the venous
condition is very important. As will be discussed later,
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Treatment of Leg Veins
A B C
Figure 9.6 Varicose veins (A) before, (B) 1 month after endovenous laser of the GSV, and (C) 1 month after sclerotherapy of residual varices
treating the below knee GSV and the SSV is associated
with higher rates of sensory nerve injuries and weighing
the benefits and risks of the extent of treatment should
be individualized to each patients clinical problem. Aggressive below knee treatment will be more acceptable for
patients with skin lesions or significant pain at the ankle
and less acceptable when treating a patient for cosmetic
concerns in the thigh or upper calf.
As discussed, tumescent anesthetic injection is essential to the safety and efficacy of the EVTA procedure. In
general approximately 5–10 mL is used for every centimeter of treated vein. The anesthetic should be injected in
the saphenous compartment immediately adjacent to the
treated vein under ultrasound guidance to ensure that the
fluid is delivered into the proper perivenous space and in
sufficient amounts to appropriately protect the saphenous
and sural nerves where they are in proximity to the GSV
and SSV respectively as well as to protect any small arteries which may be in the area of the SFJ or SPJ starting
spots for ablation. The DUS guidance also helps in making
sure that an appropriate amount of fluid is delivered to
separate the treated vein from the skin and to be sure that
vein is being completely emptied. One commonly used
rule of thumb is that there should be approximately 1 cm
diameter of fluid around the vein when it is injected to
protect surrounding structures (see Fig. 9.1).
Many in the lay public have the impression that the
varicose tributaries will ‘return to normal’ after elimination of reflux into them with EVTA. Symptoms clearly
improve after EVTA alone and the inclination for some
physicians and in the insurance industry is that additional
treatment directed at the varicose tributaries is not
needed. It is true that in many patients the tributary
varicose veins will shrink and in some patients the related
varicose veins do undergo a substantial decrease in size
following EVTA. However, the veins that shrink the most
are usually the smallest veins to start with and many of
the larger ones change little. Another consideration is that
larger (generally >
6-8 mm in diameter) varicose tributary
veins are very susceptible to developing post procedure
superficial phlebitis when not removed along with EVTA.
Regardless of how underlying saphenous incompetence
is treated, ancillary treatments are generally needed to
treat residual varices. EVTA eliminates the hemodynamic
effects of saphenous vein reflux. However, the incompetent tributaries usually remain incompetent after saphenous ablation. Eliminating the incompetent bed further in
anecdotal experience improves the hemodynamic condition of the extremity, decreases the likelihood of early
recurrences of symptoms following re-pressurizing of this
bed as well as maximizing the cosmetic benefits of the
procedure. Such additional treatments include sclerotherapy (liquid and/or foam), and ambulatory phlebectomy
(microphlebectomy) (Fig. 9.6).
In most cases, patients will motivate further treatment.
They will do so because they will either still feel uncomfortable or they will be unsatisfied with the cosmetic
outcome. In addition, one of the common causes of a
clinical recurrence encountered after surgery of EVTA
that leaves the tributary veins untreated is repressurization
of the original varicose tributary bed. The possible mechanism include recruitment of reflux in IPVs or new incompetence in another truncal vein, such as the AAGSV after
GSV ablation. This observation encourages us to recommend being aggressive in elimination of the incompetent
tributary bed.
When EVTA results in segmental or complete anatomic
failure, it is reasonable to retreat with the same technique.
Consideration for the mechanism of failure and means to
overcome it should be entertained. Failure may have been
inadequate energy deposition, inadequate vein emptying
or device failure. Optimising the technique of the second
procedure to maximize success is warranted. One must
recognize that previously treated veins are more likely to
have intraluminal webs and thrombus and may be segmentally occluded. As a result, placement of the catheters
through the entire segment may be more challenging. In
some cases several access points and the introduction of
several devices may be needed to retreat a vein in order to
completely ablate the incompetent segments.
When treating the SSV, the ablation parameters are
the same as that used to treat the GSV. However, is
Endovenous Thermal Ablation
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133
important to ensure adequate tumescent fluid to protect
the sural nerve and to separate the vein being treated from
adjacent vessels. With SSV ablation, the starting spot
should be above the level of the deep fascia to avoid injury
to small branches of the popliteal artery and to the tibial
nerve that are in close proximity to the SSV near its
popliteal termination. Generally 100 J/cm with ELA for
the first 4-5 cm followed by 70-84 J/cm is sufficient to
close the SSV.
RESULTS OF EVTA
• General comments
Both ELA and RFA are less invasive than junctional ligation and saphenous stripping, which had been the preferred method of saphenous reflux elimination until the
acceptance of thermal ablation. EVTA is safely
and effectively performed using local anesthesia in an
office setting requiring about 45–75 minutes of
time to be perform. Complete procedure times are
dependent on the number of concurrent treated veins,
length of segment(s) treated and whether ancillary procedures, such as ambulatory phlebectomy, are carried out.
Patient satisfaction has been reported to be very high following both procedures.
The total cost (cost of the procedure plus societal cost)
of endovenous procedures is likely equal to or better than
that of surgery. This is debatable in a hospital setting, but
is almost certainly true if the EVTA can be performed in
a non-specialized office setting. These techniques are
being rapidly adopted and are now being performed more
often than traditional stripping in the United States.
• Anatomical success rates
The anatomical outcomes following endovenous treatment include occlusion of the treated segment, early
failure (complete or segmental), or late recanalization
(complete or segmental). Anatomic success following
EVTA should result in the treated vein having no lumen
and either shrink to a fibrous cord <
or sonographically absent 6–12 months post-treatment.
Anatomical success with ELA and RFA of the GSV has
been reported between 85–100%. The follow-up for these
evaluations varies from three months to 4 years. To date
there is only one abstract with follow-up at 2-years reviewing an initial experience with CF that reports a similar
anatomical success rate as that reported for ELA. There
is less data following SSV with ELA and RFA (none with
CF of the SSV) but the published results are qualitatively
similar to that found with GSV ablations; 92% of patients
who are reflux-free at 1 year remain so at latest follow-up
to 5 years.
Most EVTA recanalizations occur in the first 6 and all
in the first 12 months following EVTA in every reported
series. This suggests that recanalization may be related to
insufficient thermal energy delivery to the target vein with
2.5 mm in diameter
resultant vein thrombosis rather than cicatrisation and in
some cases recanalization of the thrombus. Late clinical
recurrence is extremely unlikely in an occluded vein that
has shrunken to a non-compressible cord. Based on
this and surgical data that demonstrate the pathological
events that lead to recurrence usually take place within 2
years, later clinical recurrences are more likely related to
development of incompetence in untreated veins or vein
segments of the treated vein which were not treated (progression of disease). To a great extent, late clinical success
after EVTA is predicated by the natural history of the
venous insufficiency in a given patient, the ability of the
treating physician to identify and eliminate all incompetent pathways (often described as tactical and technical
success), as well as the success of the adjunctive procedures used to eradicate any co-existent incompetent tributary veins after EVTA.
With EVTA, in most cases the first 1–2 cm of the
treated vein beyond the SFJ or SPJ remains patent as
treatment is begun just below this level. Post EVTA
patency of segments <5cm long beyond the junction are
the most common form of anatomical failure. Clinically
nearly all of these patients benefit from the procedure.
However, the patent stump of GSV usually is connected
to a saphenous tributary which over time may reflux and
be the source of a clinical recurrance. Post treatment
patency of >
common. Less successful closure of the proximal vein
segment may be related to insufficient thermal injury to
this portion that is generally of larger caliber and less likely
to develop spasm during tumescent anesthetic administration and consequently more difficult to empty. As a result,
it is less likely to develop good device and vein wall apposition in this segment which is thought important for
optimal vein wall energy deposition to achieve successful
ablation.
Patients with a high body mass index have been shown
to have a higher rate of failure with laser and RFA. The
rationale for this observation is unclear, although it is
known that obese patients have higher central venous
pressures and a higher frequency of chronic venous
disease. EVTA success has been demonstrated in retrospective data review to be independent of vein diameter
in many studies. However, a prospective confirmation of
this conclusion has not been performed.
5 cm of treated vein segments are much less
• Side effects and complications
Adverse events following EVTA occur but almost all are
minor. Ecchymosis over the treated segment frequently
occurs and normally can last for 14 days. About one week
after EVTA, the treated vein may develop a feeling of
tightness similar to that after a strained muscle. This transient discomfort, likely related to inflammation in the
treated vein segment is self-limited and may be ameliorated with the use of nonsteroidal anti-inflammatory
drugs, ambulation and graduated compression stockings.
Both of these side effects are more commonly described
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Treatment of Leg Veins
after EVTA using existing laser protocols than for RFA
and CF but the differences in severity are small. Superficial phlebitis is another uncommon side effect after
EVTA being reported after about 5% of treatments as
mentioned previously. There are no published reports of
superficial phlebitis after EVTA progressing to deep vein
thrombosis and it has been managed in most series with
non-steroidal anti-inflammatory medication, graduated
compression hose and ambulation. As mentioned, anecdotally superficial phlebitis seems to be more common in
larger diameter tributary varicose veins or in varicose veins
that have their inflow and outflow ablated by EVTA. Concurrent phlebectomy of these veins at the time of EVTA
has been recommended to decrease the risk of this side
effect, but at this point there is no data to substantiate
this claim.
More significant adverse events reported following
EVTA include neurological injuries, skin burns and DVT.
The overall rate of these complications has been shown to
be higher in low-volume centers as compared to high
volumes centers. The nerves at highest risk include the
saphenous nerve, adjacent to the GSV below the mid-calf
perforating vein, and the sural nerve adjacent to the SSV
in the mid and lower calf. Both of these nerves have only
sensory components. The most common manifestation of
a nerve injury is a paresthesia or dysesthesia, most of
which are transient. The nerve injuries can occur with
catheter introduction, during the delivery of tumescent
anesthesia or by thermal injury related to heating of the
perivenous tissues.
Tumescent anesthesia has been demonstrated to reduce
peri-venous temperatures with laser and with RFA. The
delivery of the perivenous fluid is felt to be responsible
for the low rate of cutaneous and neurological thermal
injuries seen in the series of patients treated utilizing it.
Neurological injuries are seen after truncal vein removal
and are related to injury to nerves adjacent to the treated
vein The incidence of these adverse events are related to
the degree to which objective testing is performed to
identify them. In general, paresthesias caused by EVTA
are usually temporary with the rate of permanent paresthesias typically reported for GSV and SSV as 0–10%.
The one-week paresthesia rate following RFA was shown
to decrease from 15 to 9% after the introduction of
tumescent anesthesia. Patients treated with laser EVTA
performed without tumescent anesthetic infiltrations also
demonstrated a high rate of such injuries.
There is evidence suggesting a higher rate of nerve
injuries reported when treating the below knee GSV as
compared to the above knee segment and when treating
the lower half of the SSV. Treatment of the below knee
GSV or lower part of the SSV may be necessary in many
patients to treat to eliminate symptoms or skin disease
caused by reflux to the ankle. A retrospective review
demonstrated that below knee GSV laser ablation can be
performed with an 8% rate of mild but permanent paresthesias with adequate amounts of tumescent anesthesia.
It is also suggested by this data that sparing the treatment
of the distal 5–10 cm may accomplish clinical benefit and
potentially avoid saphenous nerve injury risk in patients
with reflux to the medial malleolus.
Skin burns following EVTA have been reported following RFA and laser. Skin burns are fortunately relatively
rare and seem be avoidable with adequate tumescent
anesthesia. The rate of skin burn in one series using RFA
was 1.7% before and 0.5% after the initiation of the use
of tumescent technique during RFA EVTA. The early
experience had rates as high as 4% that decreased to
almost 0% as the use of tumescent anesthesia became a
standard of practice.
DVT following EVTA is unusual. DVT can occur as an
extension of thrombus from the treated truncal vein
across the junctional connection into the femoral or popliteal veins. The reported rates of junctional thrombosis
following GSV EVTA varies widely. This variability may
relate to the time of the follow-up exam and the methods
used. Most published series utilizing early DUS (around
72 hours or less after EVTA) document a proximal extension for the GSV just under 1%. Those performing the
DUS later identify a lower rate. It is possible the rates are
different for different operators, for different DUS techniques or that the proximal extension of thrombus is self
limited without a clinical event. This type of DVT is
almost universally asymptomatic. The significance of this
type of thrombus extension into the femoral vein seems
to be different than that with native GSV thrombosis with
extension or when compared with typical femoral vein
thrombosis.
The incidence of junctional extension of thrombus
after SSV ablation has also been described to be low (0–
6%). In one study, the rate of popliteal extension of SSV
thrombus at 2–4 days after EVTA was demonstrated to
be related to the anatomy of the SPJ. The incidence at
48–72 hours follow-up was 0% when no SPJ existed, 3%
when a thigh extension exists but was 11% when no junctional vein can be identified just proximal to the SPJ.
Heparin was used to treat identified thrombus extensions
and all regressed. There is no published data on conservative management of transjunctional thrombus extension at
either the SPJ or SFJ. However, given that popliteal or
femoral vein obstruction develops in significantly <1% of
patients including in those series where DUS is not done
until one month at EVTA, the practice of performing early
DUS surveillance and aggressive anticoagulation of such
findings is controversial.
Neovascularity at the SFJ after EVTA, as a form of
recurrence of varicose veins, seems to be rare at 1–3 year
follow-up. Neovascularization was seen in only 2 out of
the 1222 limbs followed for up to 5 years in an industry
sponsored registry of patients treated with RFA. Longer
follow-up may be necessary to feel confident with this
observation; however, neovascularization is common
and often an early event following high-ligation and stripping (HL/S). Neovascularization, may be less common
following endovenous procedures because the junctional
tributary flow, which was usually ligated at their conflu-
Endovenous Thermal Ablation
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135
ence with the SFJ is generally not affected with GSV
EVTA.
Anecdotal reports of laser fiber fracture or retained
venous access sheaths have been made to the device manufactures and a case report exists describing a retained
vascular sheath after laser ablation. Respecting the fragile
glass laser fibers and being gentle with its handling should
help minimize laser fiber fractures. The possibility of a
laser fiber fracture should be considered with the removal
of the device in each case. Care to deliver thermal energy
only beyond the introducer sheath and away from any
other parallel placed sheaths when treating two veins
during the same procedure with any EVTA device is
essential to avoid severing segments of these sheaths. No
specific management recommendations of retained intravenous laser fiber or sheath fragments can be made based
on the data. However severed short segments of the tip
of the laser fiber are very unlikely to cause clinical effects
and are likely safely left in situ.
Two case reports of an arteriovenous fistula (AVF)
between a small popliteal artery branch and the SSV
exist. Anecdotal references have been made of additional
AVFs between the proximal GSV and the contiguous
superficial external pudendal artery. Although thought
to be related to a heat induced injury caused by the
thermal device, an AVF could be caused by a needle
injury during tumescent anesthetic administration. Ways
to minimize the risk of these AVF include careful advancement of the intravascular devices, atraumatic delivery
of the tumescent anesthetic, the use of copious
amounts of tumescent fluid and avoidance of treating the
subfascial portion of the SSV where popliteal artery
branches exist.
• Technical evaluations
There is a correlation between the amount of thermal
energy delivered and the success of laser EVTA. With
laser, energy deposition has been described as either that
deposited per centimeter of vein length (J/cm) or as that
deposited to the vein wall using a cylindrical approximation of the inner surface area of the vein (J/cm
can be considered a fluence equivalent. Durable vein
occlusion was demonstrated in an observational series as
more likely when the energy delivered exceeded 80 J/cm
with a median observation of 30 weeks.
High rates of vein occlusion and ultimate DUS disappearance was noted in a series where the thermal dose in
each segment of the GSV was tailored to the diameter in
that segment.
The ranges of energies used included 50 J/cm for veins
≤4.5 mm and 120 J/cm for vein >10 mm in diameter. No
increase in complications was seen with any of the higher
energy strategies. At this point, a prospective randomized
evaluation of the relationship of the amount of laser
energy deposition at a fixed wavelength and its effects on
the rate of anatomically successful vein obliteration and
complication rates has not been performed. However, the
2
), which
retrospective data cited supports the notion of a threshold
for high rates of success.
The settings chosen for CF are relatively new. However,
it has been shown that 116 ±
the 7 cm proximal segment treated with two 20-second
cycles and 68 ± 18 J/cm are deposited for the vein segments treated with only one 20-second cycle. These seem
to be similar to the energies used by many with laser.
The differences between the current EVTA technologies are relative small. Several retrospective analyses of
observational data have demonstrated qualitatively similar
occlusion and complication rates with a trend toward
quicker treatments and better outcomes with ELA compared with RFA. In a recent study comparing CF to ELA
with short term follow-up, equivalent treatment times and
anatomical success at 6 months were seen with slightly less
bruising and post procedure discomfort noted with CF. At
this point there are no published follow-up of the anatomical success of CF beyond 6 months although there are
two abstracts that have demonstrated similar anatomical
success (vein disappearance) with CF to ELA at one year.
ELA bruising and discomfort have been thought to be
less with continuous mode laser deposition than with
pulsed mode. Limited data suggests that these side effects
may be lessened with the use of a laser fiber with its tip
covered with a glass cap and metal sleeve as opposed to a
bare fiber. This effectively makes the fiber larger and
presumably more coagulating than cutting. Long term
evaluation of the anatomical success of such fibers is not
available at this time.
There do not appear to be any differences in the anatomical success of ELA with different wavelengths in
limited evaluations. These studies demonstrated equivalent occlusion rates for the different wavelengths when
used at similar rates of energy deposition. No differences
in the complication rates were seen in patients treated
with different wavelengths but mild differences in the
side effects of bruising and discomfort were described.
12 J/cm are deposited in
• Evaluation of clinical outcomes
Several studies have documented significant and durable
improvements in validated assessments of quality of life
following EVTA which were at least as good or better than
the improvements seen following high ligation and stripping in one study (HL/S). Evaluation of the effectiveness
of EVTA in CEAP 4–-6 patients was performed in a retrospective review of patients 6 weeks after they were
treated with RFA and laser. 85% vein occlusion was noted
overall, with significant improvements in the VCSS
(venous clinical severity scores) and APG (air plethysmography). The correction in VFI (venous filling index) on
the APG has been correlated with long-term symptomatic
relief in surgical series. Improvement in APG following
EVTA at 8 weeks following ablation has been documented.
Ulcer healing has been induced after EVTA. One report
documented an 84% success with ulcer healing with
a combination of either RFA or laser and microphle-
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