TECHNICAL NOTE Open Access
Transumbilical laparo-endoscopic single site
surgery for adrenal cortical adenoma inducing
primary aldosteronism: initial experience
Akira Miyajima*, Takahiro Maeda, Masanori Hasegawa, Toshikazu Takeda, Masaru Ishida, Takeo Kosaka, Eiji Kikuchi,
Ken Nakagawa and Mototsugu Oya
Background: We have started using laparo-endoscopic single-site surgery (LESS) in urologic surgery, although its
use has not gained momentum due to its level of difficulty. We here report our initial experience with
transumbilical LESS for adrenal cortical adenoma by using a single port with a multichannel cannula (SILS port) and
bent laparoscopic instrumentation.
Findings: A multichannel port (SILS port), bent laparoscopic instrument (Roticulator Endo Mini-Shears) and Opti4
laparoscopic electrodes were used in all cases. The intraperitoneal space was approached through the umbilicus.
The SILS port was placed through a 2 cm incision at the inner edge of the umbilicus. A 5 mm flexible laparoscope
was introduced to keep the laparoscope outside, and surgical specimens were extracted using an Endocatch bag.
In addition, as a case control study, we compared perioperative data of LESS adrenalectomy (LESS-A) with that of
conventional laparoscopic adrenalectomy (LA). We performed transumbilical LESS-A for adrenal cortical adenoma in
12 cases, beginning in December, 2009. All procedures were successfully completed, with only one incision
through the umbilicus, and without conversion to a standard laparoscopic approach. Mean operative time for
LESS-A was 121.2 ± 7.8 min, which was slightly longer than LA (110.2 ± 7.3 min). For right adrenal tumors, we used
a miniport (2 mm port) in addition to a SILS port, and were able to successfully perform adrenalectomy “with no
visible scaring”. Tumor laterality and patient BMI did not affect surgical morbidity in these procedures. Moreover,
there was no significant difference between LESS-A and LA in blood loss, analgesic requirement, hospital stay, and
Conclusions: The transumbilical approach in LESS for adrenalectomy is safe and feasible and also improves
cosmetic outcome compared with standard laparoscopic procedures. Improvements in surgical devices may aid
the further development of this approach.
Laparoscopic surgery is a well-established alternative to
open surgery across many disciplines. Although its mag-
nitude of impact varies by procedure, in general, the
benefits of laparoscopy on postoperative pain, cosmesis,
hospital stay, and convalescence are widely recognized.
Current efforts are aimed at further reducing the mor-
bidity associated with minimally invasive surgery. Cur-
rent laparoscopic techniques involve the use of three to
six small skin incisions, depending on the complexity of
the procedure. This step induces temporary incisional
pain or muscle spasms.
The umbilicus is an obliterated embryonic (E) orifice,
through which portal access can be obtained with con-
cealment of the incisional scar. Single-port laparoscopy
through the umbilicus has been termed E-NOTES, and
offers an exciting opportunity for performance of major
laparoscopic surgery with no visible scar. As such, E-
NOTES could potentially serve as a bridge between con-
ventional multiport laparoscopy and NOTES. Laparo-
scopic single-site surgery (LESS) has been reported for
cholecystectomy, appendectomy, and urologic
* Correspondence: firstname.lastname@example.org
Keio University School of Medicine, Department of Urology, 35
Shinanomachi, Shinjuku, Tokyo 160-8582, Japan
Miyajima et al. BMC Research Notes 2011, 4:364
© 2011 Miyajima et al; licensee BioMed Central Ltd. This is an open access article distributed under the terms of the Creative Commons
Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in
any medium, provided the original work is properly cited.
surgery, although its use has not gained widespread
momentum due to its high degree of difficulty. We pre-
sent here our initial experience with LESS at our institu-
tion, especially using a transumbilical approach for
This is a retrospective case control study comparing 12
laparo-endoscopic single-site surgery adrenalectomies
(LESS-As) performed between December 2009 and Sep-
tember 2010 to 24 conventional laparoscopic adrenalec-
tomies (LAs) performed between April 2006 and August
2010. Since December 2009 at our institution, transum-
bilical LESS-A has been performed in 12 patients (4
male, 8 female, mean age: 57.4 ± 3.5 y/o), who had cor-
tical adenomas inducing primary aldosteronism. From
April 2006 to September 2010, 94 conventional LAs
were performed at out institution. From this cohort, we
selected 24 patients (18 male, 6 female, mean age: 55.9
± 2.0 y/o) to serve as a control group for this study.
These patients were specifically matched in a 2:1 ratio
to index LESS-A cases with respect to disease, patient
BMI and tumor laterality. No consideration or analysis
of operative parameters and outcomes was made until
this group was definitely selected as the best comparison
cohort based on preoperative variables only. These 24
patients had undergone LA for primary aldosteronism,
with the first being performed on April 1, 2006. All pro-
cedures were performed by the same surgical team at
our hospital. Operative time, blood loss, analgesic
requirement, length of stay, postoperative complications,
and final pathology were recorded. We statistically com-
pared these two groups in terms of perioperative data
and patient scar satisfaction level, which was measured
using a 0-10 scale after surgery. Data were collected
prospectively following Institutional Review Board
approval. All procedures were performed by a single
The multichannel port (SILS port, Figure 1), bent
laparoscopic instrument (Roticulator Endo Mini-Shears,
Figure 2) and Opti4 laparoscopic electrodes were sup-
plied by Covidien (Mansfield, USA). Ultrasonic scalpel
(SonoSurg) was supplied by Olympus Surgical (Tokyo
Japan). In all cases of LESS-A, we approached the intra-
peritoneal space through the umbilicus. The SILS port
was placed through a 2 cm incision at the inner edge of
the umbilicus (Figure 3). The anterior rectus fascia was
sharply incised, and four corner fascial stay sutures were
placed. A 5 mm flexible laparoscope (Olympus Surgical,
Tokyo, Japan) was introduced to keep the laparoscope
outside the port in a location away from the surgeon’s
instruments to avoid instrument contact and maximize
surgical movement. Bent instruments were required to
create the operative angle because the insertion points
were quite close to each other (Figure 4). The instru-
ment in the right hand was placed on the left side of
the screen, and the left hand instrument was placed on
the right side of the screen. They were articulated in
opposite directions. Intraoperative dissection and vessel
cutting were performed in the usual fashion in all cases.
No cases needed extension of the umbilical incision to
remove adrenal specimens using an Endocatch bag
(Covidien, Mansfield, USA). Hemostasis was carefully
maintained and no drainage tubes were left in any of
the cases. The fascial incisions were closed with absorb-
able suture, and the umbilicus was restored with absorb-
able cutaneous stitches to its original state (Figure 5).
For right-sided disease, which we experienced in 5 cases
of this series, the liver had to be lifted. In such cases, we
inserted a 2mm Miniport (Covidien, Mansfield, USA),
from the lateral side of the abdomen. Although 2mm
port insertion appears to be scar-less, a 2 mm forceps
Figure 1 SILS port basically provides three ports for 5-12 mm
laparoscopic bent instruments and a flexible laparoscope. One
port can be compatible from 5mm to 12 mm.
Figure 2 Bent laparoscopic instruments with rotational mid-
shaft and instrument tip, and curved shaft can be changed to
desired orientation using the knob on the handle.
Miyajima et al. BMC Research Notes 2011, 4:364
Page 2 of 5
can be traumatic for the liver. To avoid traumatic proce-
dure, we used a small gauze or Securea sponge (Hogy,
Tokyo) as cushioning to lift the liver (Figure 6). In all
cases of LA, we placed 3 or 4 ports into the intraperito-
neal space in an usual fashion, and performed adrena-
lectomy by using rigid straight laparoscopic instruments
and a rigid laparoscope under pneumoperitoneum.
Groups were compared using the chi-square test and
Mann-Whitney U-test for categorical and continuous
variables, respectively. Statistical significance was set at
p < 0.05, and all reported p values are two-sided. These
analyses were performed using SPSS.
Results and Discussion
All cases of LESS-A were successfully completed with-
out any intraoperative complication and any conversion
to conventional LA. The patient background and early
perioperative data for 12 patients are shown in Table 1.
The mean operative time was not significantly different
for left side tumors (118.4 ± 13.1 min, n = 5) and right
side tumors (122.7 ± 29.3 min, n = 7) in LESS-A while
neither BMI nor tumor size was different between the
two sides. In order to investigate the difference between
LESS-A and conventional LA (18 male and 6 female;
mean age: 55.9 ± 2.0; BMI: 25.0 ± 0.7; tumor size: 14.8
± 1.4 mm; n = 24), we statistically compared these two
groups in terms of perioperative data (Table 2). Com-
pared with LA (110.2 ± 7.3 min), LESS-A appeared to
require a longer operation time (121.2 ± 7.8 min),
although the difference was not statistically significant.
In addition, there were no differences in blood loss (not
detectable in both groups), analgesic requirement (flur-
biprofen axetil 2.9 ± 0.5 mg vs. 2.9 ± 0.5 mg, p = 0.501),
and length of stay (5.2 ± 0.3 days vs. 6.1 ± 1.0 days, p =
Figure 3 Intraoperative photograph of SILS port placed in
Figure 4 Instruments were inserted through SILS port.
Figure 5 Postoperative photograph of skin incision of a
patient who underwent right adrenalectomy.
Figure 6 The liver is lifted using gauze and a miniport forceps.
4b Longer hook for Opti4 laparoscopic electrode.
Miyajima et al. BMC Research Notes 2011, 4:364
Page 3 of 5
0.687). There were no postoperative complications in
either group. All cases started oral intake and ambula-
tion on POD 1. Furthermore, we investigated the level
of patient scar satisfaction, and scar satisfaction was also
comparable in both groups (LESS: 9.67 ± 0.33; LA: 9.47
± 0.28, p = 0.889).
Prior to the adoption of a transumbilical approach, a
pararectal incision was made in one case since it
appeared to be much safer and easier to reach the target
organ and vessels compared with the transumbilical
approach. We confirmed the safety and feasibility of
LESS, and began to use the transumbilical approach.
Umbilical access does not add new risks, and appears to
yield an operative view which is the same as that in
standard laparoscopic surgery for the adrenal gland and
kidney when using a flexible laparoscope. Conventional
laparoscopic surgery requires blunt insertion of some
ports, resulting in temporary incisional pain or muscle
spasms. Moreover, the use of only one incision within
the umbilicus renders selected transperitoneal proce-
dures scarless, and the results of a cost analysis indi-
cated that LESS-A and LA are comparable in terms of
cost. Although patient scar satisfaction was comparable
between LESS-A and LA in the present study, the cos-
metic outcome of LESS can definitely be improved com-
pared with conventional laparoscopic procedures.
Two of our adrenalectomy patients had a high BMI
(30.2; 33.8) and although they had much fat tissue,
resulting in difficulty with visualization, the procedures
were successfully performed within 3 hours. In addition,
the transumbilical approach required longer hooks for
the laparoscopic electrodes (Figure 4b). Although it has
been reported that a high BMI may be a contraindica-
tion for LESS, we believe that such cases will become
treatable with LESS as its instrumentation improves .
In LESS, avoiding contact interference between the
operative instruments and the laparoscope is essential
for maintaining adequate pneumoperitoneum and redu-
cing operative stress. Therefore, coordination between
the operating surgeon and the laparoscope assistant are
vital for this procedure, since every single movement of
one affects the other. The average surgical time in the
LESS group appeared to be longer than in the conven-
tional LA group. We attempted to identify the technical
differences between these two methods. The difficulties
in LESS surgery mainly arise from the “sword fighting”
of the instruments, and this “fighting” can be reduced
Table 1 Patient background and perioperative data
No. Age Gender BMI LateralityTumor size
1 59F 19.1L8 992.5 2006
2 29F 22.3L25 952.51505
3 61M30.6R 10 1602.5 505
4 49F 19.8R 2091 2.5 2005
5 67F 23.3L 25 1332.51006
661M 29.7R 401632.52005
7 41M 27.4R12 1202.5 1504
867F33.8R52 1523 1005
9 59F 27.4L 10 1302.52505
1069M 22.4R10 120 2.5 1005
1156F 20.9R12 86 2.5504
1270F 26.3L25 1062.504
Analgesic requirement is indicated by the dose of flurbiprofen axetil.
In all cases, blood loss was not detectable.
Table 2 Comparison of perioperative data between LESS-
A and LA
57.4 ± 3.5
25.2 ± 1.3
20.8 ± 4.0
121.2 ± 7.8
55.9 ± 2.0
Left/Right side ratio
25.0 ± 0.7
14.8 ± 1.4
110.2 ± 7.3
Estimated blood loss
Hospital stay (POD)
2.9 ± 0.52.9 ± 0.50.501
5.2 ± 0.3 6.1 ± 1.00.687
Miyajima et al. BMC Research Notes 2011, 4:364
Page 4 of 5
by using bent instruments and a cross-over technique. Download full-text
However, the angles of the bent instruments need to be
adjusted, maneuvers which require a considerable
amount of time. In endoscopic surgery, one hand per-
forms dissection and the other hand performs traction,
and it is thus necessary to coordinate these bimanual
motions. Even though bent instruments have been intro-
duced, “sword fighting” remains a concern in LESS sur-
gery. “Sword fighting” occurs because two laparoscopic
instruments and a laparoscope are introduced through
the same incision. Each instrument can come into con-
tact and interfere with the other 2 instruments in a fash-
ion that resembles sword fighting, even though the
instruments are flexible or bent-neck. Therefore, target
tissue or vessels can not be easily reached.
In the early phase of our experience with LESS adre-
nalectomy, we spent quite a bit of time doing one-
handed manipulations in order to avoid sword fighting,
however, the amount of time spent has gradually
decreased as the number of procedures performed has
increased. Because the distance from the port to the
tissue in the transumbilical approach is longer than in
the conventional laparoscopic approach, the approach is
from a more tangential direction in LESS surgery. The
different angle of approach of the instrument feels dif-
ferent to that of conventional laparoscopic surgery, and
it is difficult to approach the target tissue in a straight-
forward direction. Thus, we tend to grasp the second-
or third-best site. This may contribute to an increase in
tissue re-grasping due to the inadequate or insufficient
counter-traction. Furthermore, because the gripping
power of the Roticulator was not strong enough to keep
grasping the tissue, the instruments should be further
improved so that the tissue does not slip away from the
The inclusion criteria for LESS-A are still controver-
sial. A large tumor (>10 cm) or an invasive tumor
should be approached by LA, however, we have not
experienced such cases, and some cases with severe
adhesion around the target organ or unpredictable
hemorrhaging may require additional port placement.
Although we performed LESS-A for most adrenal
tumors (PA), a prospective and randomized large series
of LESS-A will most likely be required in order to deter-
mine definite indications for LESS-A.
All procedures were successfully performed in a rea-
sonably time-efficient fashion, even in this initial experi-
ence with this new technique. We believe that
modification of the instruments and new improvements,
including suturing devices, which enable the surgeon to
approach the target organ from any angle, will make
this procedure more clinically feasible.
The transumbilical approach in LESS for adrenalectomy
is safe and feasible and also improves cosmetic outcome
compared with standard laparoscopic procedures.
Improvements in surgical devices may aid the further
development of this approach.
LESS: Laparo Endoscopic Single Site Surgery
LESS-A: LESS Adrenalectomy
LA: conventional Laparoscopic Adrenalectomy
NOTES: Natural Orifice Translumenal Endoscopic Surgery
BMI: Body Mass Index
POD: Post Operative Day
PA: Primary Aldosteronism
SILS: Single Incision Laparoscopic Surgery
AM drafted the first manuscript. TM and MI helped to draft the manuscript
and analyze data statistically. MH, TT, TK, EK and KN cared for the patient.
MO is the chair of this department. All authors reviewed the report and
approved the final version of the manuscript.
The authors declare that they have no competing interests.
Received: 8 October 2010 Accepted: 24 September 2011
Published: 24 September 2011
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Cite this article as: Miyajima et al.: Transumbilical laparo-endoscopic
single site surgery for adrenal cortical adenoma inducing primary
aldosteronism: initial experience. BMC Research Notes 2011 4:364.
Miyajima et al. BMC Research Notes 2011, 4:364
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