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ARC Journal of Surgery
Volume 4, Issue 3, 2018, PP 5-10
ISSN 2455-572X
DOI: http://dx.doi.org/10.20431/2455-572X.0403002
www.arcjournals.org
ARC Journal of Surgery Page |5
Comparison of Monopolar and Segmental Radiofrequency
Ablation in the Treatment of Lower Limb Chronic Venous
Insufficiency
Jun-Yi Ryan TAN, Zhiwen Joseph LO, Pravin LINGAM, Qiantai HONG, Enming YONG,
Sadhana CHANDRASEKAR, Glenn Wei Leong TAN
Vascular Surgery Service, Department of General Surgery, Tan Tock Seng Hospital, Singapore
1. INTRODUCTION
Chronic venous insufficiency (CVI) is a
prevalent issue, affecting an average of 10-15%
of men and 20-25% of women worldwide1.
Surgical treatment of lower limb CVI has
progressed greatly since the days of open ligation
and stripping to more minimally invasive
procedures such as foam sclerotherapy and most
recently endothermal ablation technologies such
as endovenous laser therapy (EVLT) and
endovenous radiofrequency ablation (RFA)2.
EVLT and RFA have recently been
recommended as first-line interventions for CVI
by 2013 NICE guidelines3 and have been shown
to be superior to open surgery and foam
sclerotherapy4. 4 main RFA systems are available
commercially – Covidien ClosureFast™
(Medtronic, USA), EVRF® (F Care Systems,
Belgium), RFiTT® (Celon AG, Germany) and
VeinClear™ (RF Medical, South Korea).
Covidien ClosureFast™, a segmental RFA
system, and EVRF®, a monopolar RFA system,
have both been shown to be safe and efficacious5,
6. However, a recent 2015 meta-analysis on the 4
commercially available RFA systems revealed
far fewer publications7 on EVRF® data as
compared to Covidien ClosureFast™, with no
previous direct comparisons of the monopolar
and segmental systems. As such, in our study we
aim to bridge this gap in existing knowledge by
comparing the outcomes in patients with lower
limb CVI treated with monopolar (EVRF®, F
Care Systems, Belgium) versus segmental
(Covidien® ClosureFast™, Medtronic, USA)
radiofrequency ablation (RFA) therapy.
*Corresponding Author: Zhiwen Joseph LO, Vascular Surgery Service, Department of General Surgery,
Tan Tock Seng Hospital,11 Jalan Tan Tock Seng, Singapore , Email: zhiwen@gmail.com
Abstract
Introduction: There are 4 commercially available RFA systems for endovenous ablation of lower limb varicose
veins. We aim to compare outcomes in patients with chronic venous insufficiency treated by monopolar
(EVRF®, F Care Systems, Belgium) and segmental (ClosureFast™, Medtronic, USA) radiofrequency ablation
(RFA)
Methods: Retrospective review of 288 limbs (189 patients) treated from 2014–2015, evaluating demographics,
comorbidities, venous disease grading, pre-operative venous duplex, surgical procedure and post-operative
outcomes.
Results: 146 limbs were treated by monopolar RFA, 142 limbs by segmental RFA. Both groups were similar in
patient characteristics. In addition to long saphenous vein ablation, anterior accessory great saphenous vein
(AAGSV) (monopolar: 20%, segmental: 10%, p=0.01) and short saphenous vein RFA (monopolar: 14%,
segmental: 8%, p=0.14) were performed. Post-operative outcomes were similar in both groups. Transient
superficial neuropathy was 8% in both groups (p=0.83), phlebitis occurred in 4% of monopolar group and 1%
of segmental group (p=0.28). No deep vein thrombosis nor recurrences occurred.
Conclusion: Both monopolar and segmental RFA are safe and efficacious. The shorter ablation tip of
monopolar RFA enables the ease for ablation of shorter veins, such as the AAGSV.
Keywords: Endovenous Radiofrequency Ablation, Varicose Veins, Chronic Venous Insufficiency, Anterior
Accessory Great Saphenous Vein
Comparison of Monopolar and Segmental Radiofrequency Ablation in the Treatment of Lower Limb
Chronic Venous Insufficiency
ARC Journal of Surgery Page |6
2. METHODS
2.1. Study Design
This study was a retrospective analysis of a total
of 288 limbs treated with endovenous RFA from
January 2014 to May 2015 at a 1,500-bed tertiary
referral university hospital. Factors investigated
included patient demographics, co-morbidities,
venous disease clinical manifestation (CEAP
Classification), pre-operative venous duplex
mapping, surgical procedure and post-operative
outcomes. Patient co-morbidities were
determined by American Society of
Anaesthesiologists (ASA) Classification,
smoking history, type 2 diabetes mellitus and
control, peripheral arterial disease and previous
venous surgery.
All patients were encouraged to undergo a trial of
lifestyle modification and graduated compression
stockings before surgical intervention. Patients
with C6 venous disease were treated with 4-layer
compression bandaging to promote ulcer healing
prior to any surgical intervention. The decision
for treatment with segmental or monopolar RFA
was based on surgeon’s preference. All
procedures were carried out by trained consultant
vascular surgeons who were experienced and
proficient in both systems.
Pre-operatively, patients routinely underwent
venous duplex mapping at our local vascular
diagnostic laboratory by trained vascular
scientists according to Society of Vascular
Ultrasound guidelines, using Philips iU22
ultrasound machines (Philips, USA). Sapheno-
femoral junction (SFJ) incompetence, great
saphenous vein (GSV) reflux, sapheno-popliteal
junction (SPJ) incompetence, short saphenous
vein (SSV) reflux and deep venous reflux were
assessed in the venous duplex mapping. Anterior
accessory great saphenous vein (AAGSV)
incompetence is also evaluated as part of the
diagnostic protocol.
2.2. Devices and Technique
All cases were carried out under general or
regional anaesthesia, with no routine intravenous
pre-operative antibiotics or pharmacological
deep vein thrombosis prophylaxis given.
Ultrasound-guided venous punctures were
performed with Philips iU22 ultrasound
machines (Philips, USA). Access was achieved at
below knee GSV under ultrasound guidance with
a 21G needle, after which a 7F sheath was
inserted using the Seldinger technique and
flushed with heparinised saline. Tumescent
anaesthesia (480ml of saline mixed with 20ml
1% lignocaine, 16ml 8.4% sodium bicarbonate
and 60 units 1:1000 adrenaline) was administered
prior to endovenous ablation. Intra-operatively,
ablation of the AAGSV would be attempted if
reflux were found, while SSV reflux was treated
only with the concomitant presence of SPJ
incompetence.
In the monopolar group, the EVRF® RFA
system (F Care Systems, Belgium) with the
CR45i catheter were used for ablation. The
CR45i catheter delivers power of up to 25W and
has an active catheter tip of 0.5cm. The CR45i
catheter was inserted and positioned 2cm from
the SFJ. Ablation of the GSV was carried out at
25W within the fascia envelope and at 22W when
not enveloped by fascia. A pull-back technique
was employed for ablation and the pull-back rate
was 0.5cm (1 marking) every 3 beeps (5-
6seconds) as per manufacturer instructions for
use.
In the segmental group, the ClosureFast™
system (Medtronic, USA) was used with a
ClosureFast™ Endovenous RFA catheter and
ClosureRFG™ radiofrequency generator. The
ClosureFast™ catheter has a 3cm or 7cm active
catheter tip and in view of financial
considerations, only 1 is utilized for each patient.
The ClosureFast™ catheter was inserted and
positioned 2cm distally from the SFJ. Ablation
was carried out in 20-second cycles from 40W
(120˚C) to 10W. Two cycles were applied for the
initial 7cm segment and one cycle per segment
subsequently. The catheter was pulled back at
2.5cm or 6.5cm intervals after each ablation cycle
to allow for a 0.5cm segment of overlap, as per
manufacturer guidelines.
All patients had an on-table ultrasound post-
procedure to ensure complete ablation of GSV
and to ensure the absence of deep vein
thrombosis within the femoral vein. All
procedures were completed with stab avulsion
phlebectomies. Incision sites were closed with
Steri-Strips™ (3M, USA) and dressed with 3M
Coban™ 2 Layer Compression bandage (3M,
USA). This bandage would be removed on post-
operative day 1, exchanged for a light-weight
stocking TubigripTM (Molnlycke Health Care,
Sweden) and continued until review in clinic.
Oral paracetamol or non-steroidal anti-
inflammatory drugs were prescribed for post-
operative analgesia. Patients were reviewed in
clinic 6 weeks post-operatively and assessed
clinically for symptoms of complications such as
Comparison of Monopolar and Segmental Radiofrequency Ablation in the Treatment of Lower Limb
Chronic Venous Insufficiency
ARC Journal of Surgery Page |7
transient neuropathy, phlebitis, deep venous
thrombosis and clinical recurrences. Repeat
ultrasound venous duplex mapping will be
performed should there be any suspicion for
clinical recurrences.
2.3. Statistics
Factors investigated were evaluated using
descriptive statistics. Percentages were used for
categorical data and means for continuous data.
Comparisons between groups for categorical data
were made using Chi-square tests, while
comparisons made between continuous data were
made with the Student’s t-test. All p values were
2 tailed and p values ≤0.05 were considered
statistically significant. SPSS 13.0 (Illinois,
USA) was used for statistical analysis.
3. RESULTS
From January 2014 to May 2015, 189 patients
(288 limbs) were treated with endovenous
radiofrequency ablation at our institution (Table
1). There was an equal distribution between both
treatment modalities, with 146 limbs treated with
monopolar RFA and 142 limbs treated with
segmental RFA. Of these, 55 patients (110 limbs)
of the monoplar group and 44 patients (88 limbs)
of the segmental group had bilateral chronic
venous insufficiency that was treated.
Both groups were largely similar in terms of
patient demographics and comorbidity profile
(Table 1). The mean age of our patients was 58
(27 – 83) years while the mean Body Mass Index
was 26.3 (16.6 – 45.1) kg/m2. Of the 288 limbs
treated, 174 were female while 114 were male.
Majority of patients were of American Society of
Anesthesiologists (ASA) Class I and II (92% in
monopolar and 83% in segmental) while we had
few smokers (27% in monopoolar and 18% in
segmental) and Type 2 diabetics (10% in
monopolar and 18% in segmental). Significantly,
no patients had concomitant arterio-venous
disease. Minority had undergone previous
venous surgery (5% in monopolar and 3% in
segmental).
In terms of pre-operative CEAP venous disease
manifestation (Table 2), within the monopolar
group patients with C2-C5 disease were 29%,
2%, 36%, 23%, 10% respectively. Similarly in
the segmental group, patients with C1-C6 disease
were 4%, 19%, 6%, 32%, 26% and 13%
respectively. On pre-operative venous duplex
scanning, all limbs treated had GSV reflux,
majority had SFJ incompetence (88% in
monopolar, 80% in segmental, p=0.07) while
half had SSV reflux (51% in monopolar and 49%
in segmental, p=0.73) and a third had
concomitant deep venous reflux (29% in
monopolar and 34% in segmental, p=0.38).
There was a significant difference between the
veins ablated in both groups. All patients
underwent LSV radiofrequency ablation.
However, in addition to LSV RFA, there were
significantly far more in the monopolar group
that had undergone AAGSV ablation as
compared to the segmental group (Table 3). 29
(20%) limbs in the monopolar group underwent
AAGSV ablation as compared to only 4 (3%) in
the segmental group and this was found to be
statistically significant by chi squared analysis
(p=0.01). A similar trend is seen in SSV
ablations, with 21 (14%) ablated in the
monopolar group compared to 12 (8%) in the
segmental group. Almost all patients underwent
phlebectomies, 144 (99%) in the monopolar
group and 139 (98%) in the segmental group.
Post-operative complications were few and there
were no statistical differences between both
groups. There were 11 (8%) limbs with transient
neuropathy in the monopolar group and 12 (8%)
in the segmental group. None of the patients
developed permanent neuropathy. There were 6
(4%) with phlebitis in the monopolar group
compared to 2 (1%) in the segmental group.
There were significantly no incidences of deep
venous thrombosis or clinical recurrences within
both groups (Table 3).
Table1. Patient characteristics
Monopolar
RFA
(n=146 limbs)
(n=91 patients)
Segmental
RFA
(n=142 limbs)
(n=98 patients)
p value
(Chi-
squared)
Demographics Male : Female
Average age (range)
Average BMI (range)
64 (44%) : 82 (56%)
57.9 (27-78)
26.0 (17.3-45.1)
50 (35%) : 92 (65%)
58.6 (37-83)
26.6 (16.6-41.9)
0.15
0.62*
0.34*
Ethnicity Chinese
105 (72%)
100 (71%)
0.79
Comparison of Monopolar and Segmental Radiofrequency Ablation in the Treatment of Lower Limb
Chronic Venous Insufficiency
ARC Journal of Surgery Page |8
Indian
Malay
Others
25 (18%)
8 (5%)
8 (5%)
24 (17%)
9 (6%)
9 (6%)
1.00
0.81
0.81
Treated Limbs Right : Left
Bilateral
72 (49%) : 74 (51%)
110 (76%)
71 (50%) : 71 (50%)
88 (63%)
1.00
0.02
Co-morbidities ASA Classification 1
ASA Classification 2
ASA Classification 3
Smoker
Type 2 diabetes mellitus
Good DM Control (HbA1c ≤ 7%)
Peripheral arterial disease
Previous venous surgery
12 (8%)
122 (84%)
12 (8%)
40 (27%)
15 (10%)
7/15 (47%)
0 (0%)
8 (5%)
20 (14%)
98 (69%)
24 (17%)
26 (18%)
26 (18%)
21/26 (81%)
0 (0%)
4 (3%)
0.13
0.01
0.03
0.07
0.06
0.04
N.A.
0.38
*Unpaired T-test ASA: American Society of Anaesthesiologists; BMI: body mass index; DM: Diabetes Mellitus;
RFA: Radiofrequency Ablation
Table2. Venous Disease
Monopolar
RFA
(n=146 limbs)
(n=91 patients)
Segmental
RFA
(n=142 limbs)
(n=98 patients)
p value
(Chi-
squared)
Venous Disease
Clinical Manifestation (CEAP) 1
2
3
4
5
6
0 (0%)
43 (29%)
3 (2%)
52 (36%)
33 (23%)
15 (10%)
5 (4%)
27 (19%)
9 (6%)
46 (32%)
37 (26%)
18 (13%)
0.03
0.04
0.08
0.62
0.58
0.58
Pre-op Venous Duplex
SFJ incompetence
LSV reflux
SPJ incompetence
SSV reflux
Deep veins reflux
129 (88%)
146 (100%)
27 (18%)
74 (51%)
42 (29%)
114 (80%)
142 (100%)
6 (4%)
69 (49%)
48 (34%)
0.07
1.00
0.01
0.73
0.38
AAGSV: anterior accessory great saphenous vein; LSV: long saphenous vein ; RFA: radiofrequency ablation ;
SFJ: sapheno-femoral junction ; SPJ: sapheno-popliteal junction ; SSV: short saphenous vein
Table3. Surgical Procedure and Post-operative Complications
Monopolar
RFA
(n=146 limbs)
(n=91 patients)
Segmental
RFA
(n=142 limbs)
(n=98 patients)
p value
(Fisher’s 2-
tailed)
Surgical Procedure
AAGSV ablation
SSV ablation
SPJ ligation
Phlebectomy
29 (20%)
21 (14%)
0
144 (99%)
4 (3%)
12 (8%)
0
139 (98%)
0.01
0.14
N.A.
0.68
Post-op Outcomes
Transient neuropathy
Permanent neuropathy
Phlebitis
DVT
Recurrence
11 (8%)
0
6 (4%)
0
0
12 (8%)
0
2 (1%)
0
0
0.83
N.A.
0.28
N.A.
N.A.
AAGSV: anterior accessory great saphenous vein; DVT: deep vein thrombosis; LSV: long saphenous vein ; RFA:
radiofrequency ablation ; SPJ: sapheno-popliteal junction ; SSV: short saphenous vein
Comparison of Monopolar and Segmental Radiofrequency Ablation in the Treatment of Lower Limb
Chronic Venous Insufficiency
ARC Journal of Surgery Page |9
4. DISCUSSION
Within the literature, this is the first study which
directly compared monopolar and segmental
radiofrequency ablation for lower limb CVI. Our
study is also the largest series of monopolar
radiofrequency ablation for lower limb CVI
within Asia. The most significant finding of our
study was that more short vein ablations, such as
AAGSV ablations, were carried out with the
monopolar system. The AAGSV was ablated in
20% of ablations carried out in the monopolar
group as compared to only 3% in the segmental
group. This is likely a result of the shorter, 0.5cm
active catheter tip of the of the monopolar
EVRF® system, which has a 0.5cm active
catheter tip as compared to the 3cm or 7cm active
catheter tip of the ClosureFast™ catheter. In
current literature, there is a low reported rate of
AAGSV ablations in most studies5, 8, ranging
from 2.7% - 10% in various studies on
endothermal ablation. Ablation of the AAGSV is
not well studied although incidence of isolated
AAGSV reflux has been reported at 10%9 and its
clinical significance has been suggested in its
role in causing recurrence after GSV ablation or
stripping10-12 although currently, there is no
consensus on its treatment, even in the absence of
reflux.
Similarly, in our study we saw a similar trend in
more SSV ablations carried out in the monopolar
group (14%) as compared to the segmental group
(8%), and this is consistent with that described in
existing literature – in a 2015 study on the
monopolar system by Spiliopoulos et al5 14.8%
of procedures involved ablation of the SSV,
while only 5% were ablated in a 2015 segmental
study13.
Our study’s findings also further reiterate the
safety and efficacy of radiofrequency ablation as
a treatment modality for lower limb CVI,
demonstrating favourable surgical outcomes with
low rates of post-operative complications in both
the segmental and monopolar groups with no
significant differences between both groups. Our
study had no incidences of deep venous
thrombosis and clinical recurrences, which is in
keeping with existing literature that shows a <1%
risk of deep venous thrombosis14. In our series
there was a 2.7% incidence of post-operative
phlebitis, in keeping with current reported
literature of 0.8 – 5.5%6, 15. However, although
our study reported a low rate of 8% incidence of
transient neuropathy in both groups, existing
literature has reported slightly lower rates of
post-operative transient neuropathy, with 3-5%
and 2% reported in segmental6, 15, 16 and
monopolar5 studies respectively. Notably none of
the incidences of transient neuropathy were
permanent in our study and in reported literature.
A possible explanation for the slightly higher
incidence in transient neuropathy in our series,
although still low, compared to that of existing
literature could be in the ethnic differences in our
patients, with 71.5% of Chinese descent, which
has anecdotally been associated with a higher
incidence of incomplete fascial covering over the
GSV.
Limitations of our study include the retrospective
nature of our study design, with its associated
selection and information biases. In terms of
chronic venous insufficiency grading, we
adopted the CEAP classification and did not use
the venous severity score. Post-operative
recurrences were evaluated clinically, with no
formal surveillance ultrasound venous duplex.
We also were not able to compare the efficacy of
the other 2 endovenous radiofrequency ablation
devices on the market.
5. CONCLUSION
Both monopolar and segmental RFA are safe
endovenous modalities in the treatment of lower
limb CVI, with similar clinical outcomes and low
complication rates. The significant advantage of
monopolar over segmental RFA would be its
shorter active catheter tip of 0.5cm, which
enables the ease for ablation of shorter veins,
such as the AAGSV.
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Citation: Jun-Yi Ryan TAN, Zhiwen Joseph LO, Pravin LINGAM, Qiantai HONG, Enming YONG, Sadhana
CHANDRASEKAR, Glenn Wei Leong TAN. Comparison of Monopolar and Segmental Radiofrequency Ablation
in the Treatment of Lower Limb Chronic Venous Insufficiency.ARC Journal of Surgery.2018;4(3):5-
10.doi:dx.doi.org/ 10.20431/ 2455-572X. 0403002.
Copyright: © 2018 Authors. This is an open-access article distributed under the terms of the Creative Commons
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