Keywords Robot-assisted surgery - Mastectomy - Free tissue flaps - Reconstructive surgical
procedures
INTRODUCTION
In the search for optimization of female breast reconstruction, minimally invasive
procedures offer unprecedented advantages [1 ]. Minimally invasive nipple-sparing mastectomies (NSMs) mainly encompass endoscopic
surgery and robot-assisted operations through a short and inconspicuous incision,
usually located in the lateral breast border. When compared to endoscopic NSM, robotic
surgery provides better three-dimensional vision for surgeons, enabling more precise
dissection and hemostasis, as well as easier and less straining handling [2 ]. Although the visible cutaneous scars are markedly diminished by the aforementioned
techniques, they also pose new challenges to reconstructive surgeons, as key steps
in free flap reconstruction, such as vascular anastomosis and flap insetting, are
significantly complicated. In this article, we will discuss the technique of the senior
author ( JJH) to optimize flap inset after robot-assisted NSM (R-NSM). Our technique
can be applied to the inset of the deep inferior epigastric artery perforator (DIEP)
flap, our primary workhorse flap, as well as any other flaps, and helps to shape the
medial inferior aspect of the breast border.
IDEA
The main difficulties in performing microsurgical breast reconstruction after robotic-assisted
mastectomy are microsurgical anastomosis via a small incision and transferring the
flap into the pocket, insetting it, and shaping it. Via a small lateral incision,
it is difficult to push and bring the flap into the mastectomy pocket all the way
to reach the most medial inferior point. Even after successfully doing so, the gravity
effect remains challenging as the flap may drop inferiorly and laterally with time
without a suspension suture. Progressive lateral deviation and medial pole sunken
may occur. The idea of performing transcutaneous medial fixation sutures was to both
assist in flap transfer and provide suspension fixation of the flap in the medial
inferior pole. In order to assist in flap transfer, the sutures are designed first
to be dynamic. Suture loops are placed transcutaneously and left inside the pocket
without any nodes made. The sutures outside the pocket are temporarily tapped on the
chest wall skin. Before flap transfer, the dermis of the flap margin is sutured to
the suture loops. By pulling the sutures outside the mastectomy pocket, the sutures
first play a guiding role to bring the flap to the most medial inferior pole of the
reconstructed breast. After confirming the location, the sutures are tied to provide
permanent fixation of the flap and prevent dropping.
Surgical steps
The surgical steps prior to the insetting and medial fixation sutures are as follows:
(1) sentinel lymph node biopsy, which may be extended to axillary lymph node dissection
depending on the intraoperative pathological assessment, and preparation for robotic
docking (or another form of minimally invasive mastectomy) through a 4–5 cm skin incision
on the anterior axillary line is performed by the breast surgeons. At the same time,
the flap (usually a DIEP or alternatively a perforator [profunda artery perforator]
flap) is raised by the plastic surgeons, and the pedicle is not transected yet; and
(2) R-NSM using the da Vinci Xi surgical system (Intuitive Surgical, Denzlingen, Germany),
or any form of minimal invasive mastectomy, is completed.
The surgical steps for the fixation sutures are as follows ([Fig. 1 ], [Supplemental Video 1 ]): (1) before vascular anastomosis, the breast skin is marked at 7:00, 7:30, and
8:00 o’clock (left breast) or 4:00, 4:30, and 5:00 o’clock (right breast) at the preferred
lower medial border of the breast for the medial suspension sutures; (2) three 4/0
nylon suture loops are placed transcutaneously at the markings on the pocket by a
reusable suture needle. The reusable suture needle is removed after the loops are
placed inside the pocket; (3) the flap pedicle is transected and anastomosed, usually
to the thoracodorsal or lateral thoracic vessels. During anastomosis, the flap is
positioned outside on the breast and temporarily fixed to the skin while a second
team is closing the donor site. Zone IV and excess flap tissue are excised; (4) deepithelialization
of the flap is performed; (5) temporary insetting permits the identification of the
three corresponding points of the flap that will be sutured to the 7:00, 7:30, and
8:00 o’clock or 4:00, 4:30, and 5:00 o’clock positions at the preferred lower medial
border of the breast. The points are marked; (6) the three nylon loops are then sutured
to the dermis of the marked corresponding medial parts of the deepithelialized flap
by two 4/0 nylon sutures per loop; (7) flap is placed into the pocket by a simultaneous
gentle pull on the three medial fixation sutures and a lateral push; (8) fixation
sutures are tied, cut at the skin level, and buried. Thereby, the mediocaudal breast
border is firmly and permanently affixed; or (9) additional measures for breast shaping
such as inframammary fold sutures or other fixation sutures may be performed to symmetrize
the breast shape to the contralateral site.
Fig. 1. Schematic draft of the transcutaneous medial fixation sutures. (A) Three nylon sutures
are transcutaneously attached at 4:00, 4:30, and 5:00 o’clock (right breast) or 7:00,
7:30, and 8:00 o’clock (left breast) to the deepithelialized flap. The sutures help
in the inset process through a small lateral incision in the breast after robot-assisted
nipple-sparing mastectomy and in fixing the flap at the medial inferior aspect of
the breast. (B) By gently pulling the stitches, the flap is then transferred successfully
into the breast pocket. Three knots were made accordingly.
Supplemental Video 1. Video of the transcutaneous medial fixation sutures of a deep
inferior epigastric artery perforator flap on the right breast in a 42-year-old patient
after robot-assisted nipple-sparing mastectomy. The operating surgeon is the senior
author (JJH). Supplemental data can be found at: https://doi.org/10.5999/aps.2021.00843.v001
DISCUSSION
A thicker dermis, differences in the cellular and molecular processes of scar maturation,
and a significantly higher rate of hypertrophic scars in Asians when compared to Caucasians
are well documented [3 ]. In Asian patient populations, wherein concerns about large and visible scars are
widespread, minimally invasive surgery including robotic surgery has therefore gained
increasing popularity since its first introduction [4 ]. R-NSM and immediate microsurgical DIEP flap reconstruction is our primary approach
for most patients [5 ], while the majority of the current literature describes implant-based or pedicled
latissimus dorsi flaps for immediate breast reconstruction after R-NSM [6 ]
[7 ]
[8 ]
[9 ]
[10 ]. Despite the unquestionable benefits of R-NSM for patients, as recently reported
in a large-scale South Korean consortium [11 ], plastic surgeons face new challenges when it comes to flap inset. Medializing the
flap, especially to the inferior medial pole, is extremely difficult via a 4–5 cm
long incision at the lateral breast border. In early microvascular free flap reconstructions
after R-NSM, we frequently observed a lateral shift of formerly well-placed flaps,
as seen in a 33-year-old patient ([Fig. 2 ]) after DIEP flap reconstruction. Correction of this phenomenon via the original
incision is difficult once this lateralization is established and even more so when
adjuvant radiotherapy has been carried out. Thus, controlled and tailored insetting
during reconstruction is of the utmost importance, and recognition of this issue prompted
the development of new strategies.
Fig. 2. Lateral shift of the flap without transcutaneous medial fixation sutures (28 weeks
after surgery). In this 33-year-old patient, the right breast was reconstructed by
a deep inferior epigastric artery perforator flap after robot-assisted nipple-sparing
mastectomy due to breast cancer. She also received postmastectomy radiotherapy due
to a large tumor size before neoadjuvant chemotherapy. A lateral shift of the right
breast with loss of definition of the medial inferior aspect of the breast occurred
28 weeks after surgery.
Our approach consists of pre-set transcutaneous permanent sutures (preferred over
slowly resorbable sutures due to their durability) that have two purposes. The main
purpose is to maintain the mediolateral border of the breast without creating new
visible scars. Even if the initially 4–5 cm long incision expands after fixation of
the single robotic port and the R-NSM to a certain degree, reaching the medial pocket
through it and applying accurate fixation sutures is challenging. Our proposed technique
permits an easy, scarless, and precise flap inset.
The second purpose is a simplified insetting of the flap into the pocket without involuntary
flap folding by a combination of pull maneuvers on the fixation sutures and pushing
the flap through the narrow skin incision into the pocket.
Transcutaneous sutures were earlier applied in plastic surgery, such as for shaping
in rhinoplasty [12 ] or the breast [13 ], and are used to address inaccessible areas. In this sense, we used a known technique
and translated it to the difficult context of breast shaping after robot-assisted
mastectomy. In addition, for DIEP flaps, pre-shaping of the flap to the desired cone
shape before implanting it into the pocket has been suggested [14 ], although no work to date has addressed the specific requirements for DIEP inset
through a small incision on the lateral thorax as found in our cases.
An obvious concern in our technique is the inevitable creation of retracted scars
following the tying of the transcutaneous sutures. However, in our experience, the
initially visible retractions start to resolve within 4 weeks and completely disappear
after 3 to 4 months, as shown in [Fig. 3 ]. In the Taiwanese patient population described in the present manuscript with relatively
small flap volumes, transcutaneous anchoring sutures were only needed at the mentioned
positions. In larger breasts, additional anchoring sutures may be considered at the
upper border of the flap. In these locations, however, we do not recommend transcutaneous
anchoring sutures, as these lead to cosmetically unpleasing skin retraction that we
have experienced first-hand in the initial stages. Even with placement of the fixation
sutures inside the mastectomy pocket by suturing the flap to the chest wall, retraction
may still occur, leading to a disadvantage in terms of cosmesis that could be a permanent
problem.
Fig. 3. Patient after a deep inferior epigastric artery perforator (DIEP) flap and transcutaneous
medial fixation sutures of the right breast. Breast cancer (ductal carcinoma in situ ) of the left breast in this 54-year-old patient was treated with minimally invasive
nipple-sparing mastectomy via a small lateral incision and free DIEP flap reconstruction.
Her mastectomy specimen weighed 324 g and a free DIEP was transferred using the thoracodorsal
artery and vein as recipient vessels. Before flap inset, transcutaneous medial fixation
sutures were placed. The flap, which was de-epithelialized in the buried part, was
sutured with the transcutaneous medial fixation suture, and the flap was then pushed
into the mastectomy pocket with assistance of pulling from the transcutaneous sutures.
(A) Preoperative photo. (B) A free DIEP flap weighing 372 g was harvested for reconstruction.
(C) The initially visible retracted scars over the medial inferior of the left breast
began to resolve at a 3-month follow-up examination. The position of the flap was
well maintained, without lateral deviation. The donor site scar was also present.
(D, E) The anterior and left lateral view of the breast at a postoperative follow-up
of 17 months. The scar of the transcutaneous medial fixation suture was completely
invisible.
Collectively, we herein propose a simple technique for shaping the medial breast border
of free flaps after minimally invasive NSM, including R-NSM. A more elaborate scientific
evaluation of our technique is planned once a sufficient number of patient cases and
adequate follow-up time are reached.
NOTES
Ethical approval
The study was performed in accordance with the principles of the Declaration of Helsinki.
Patient consent
The patients provided written informed consent for the publication and the use of
their images.
Author contribution
Conceptualization: JJ Huang. Data curation: JJ Huang. Funding acquisition: BS Kim.
Methodology: WL Kuo, DC Cheong, JJ Huang. Project administration: BS Kim. Visualization:
BS Kim, N Lindenblatt. Writing-original draft: BS Kim, JJ Huang. Writing-review &
editing: WL Kuo, DC Cheong, N Lindenblatt, JJ Huang.
