**2. Minimally invasive surgery in breast reconstruction**

Donor site concerns including the risk of hernia or abdominal bulge following DIEP flap reconstruction have driven plastic surgeons to explore minimally invasive options for flap harvest. Hernia, muscle-bulging, and decreased core strength are the most significant donor site complications that minimally invasive surgery seeks to correct. Multiple studies have shown decreased abdominal wall morbidity as muscle preserving techniques increase [3–10]. The increased abdominal wall morbidity is typically attributed to 3 factors: weakened musculature, denervated musculature, and violation of the anterior sheath. The first, inclusion of the rectus abdominus in the flap design (TRAM or ms-TRAM) may be minimized by performing a true perforator flap with perforators selected to minimize muscular disruption. The second, denervation of the rectus abdominus can be reduced by selecting medial row perforators when suitable and using a nerve-sparing or at least nerve-repairing technique for any motor nerves encountered during pedicle dissection [11]. The final factor associated with abdominal wall morbidity is the violation of the anterior sheath that occurs during dissection of the deep inferior epigastric vessels from the level of the perforating vessels to their origin off the external iliac artery and vein (**Figure 2**). The anterior rectus sheath is the primary strength layer of the abdominal wall, especially below the arcuate line where the only barrier between the rectus abdominis and the peritoneal cavity is the thin transversalis fascia and peritoneum.

To limit the fascial incision, short pedicle techniques were described by Saint-Cyr [12]. However, as the pedicle is shortened, the caliber of the artery and vein decrease. Additionally, the degrees of surgical freedom when performing the microsurgical anastomoses are reduced which can lead to increased microscopic complications in less experienced hands. Furthermore, visualization of the vessels is limited with a small fascial incision. These challenges have inspired plastic surgeons to innovate using minimally-invasive tools commonly used in other surgical disciplines.

#### **2.1 Laparoscopic DIEP flap harvest**

In 2017, a group in France published the first feasibility study of a laparoscopic technique for DIEP flap harvest [13]. They utilized a preperitoneal or total extraperitoneal (TEP) laparoscopic technique. The TEP technique uses insufflation to bluntly open the space between the posterior sheath/transversalis fascia and the posterior surface of the rectus abdominus muscles. Once this plane is separated, the vessels can be easily seen and dissected free of the muscles from the level of external iliacs to the perforating vessels without entering the abdominal cavity. The vessels are clipped and divided at their origin, and the entire length is extracted through a minimal fascial

**Figure 2.**

*(A) Traditional harvest of open DIEP flap with longitudinal splitting of muscle and fascia. (B) Ruler illustrates the nearly 15 cm incision of the anterior sheath required for pedicle dissection.*

incision created during the open perforator dissection. In their series of 5 cadavers (10 hemiabdominal dissections), they were able to achieve a mean anterior fascial incision length of 3 cm compared to 12 cm for the traditional approach.

Laparoscopic DIEP flap harvest has subsequently been adopted by other groups. In 2020, a group at the University of Pennsylvania reported the then largest clinical series of patients who underwent laparoscopically-assisted harvest of DIEP vessels [14]. They reported a novel variation on previously published techniques to maximize flap blood flow while simultaneously reducing abdominal wall morbidity. They utilize a two-stage surgical delay technique to optimize the perforator most suitable for laparoscopic harvest. Prior to the initial procedure, a single perforator is selected not based on caliber but rather on location (low, central) and a short intramuscular course as seen on CT angiogram. At the initial operation, all other perforators and the superficial inferior epigastric artery and vein are ligated. This prompts the remaining perforator to dilate in response to relative tissue ischemia. At the second stage 2 weeks later, the single perforator is dissected through a minimal fascial incision and the pedicle is mobilized using a preperitoneal (TEP) approach similar to the description above. In their case series of 33 patients (57 flaps), the mean fascial incision length was 2 cm with 2 pedicle transections occurring during dissection which required repair.

### **2.2 Robotic DIEP flap harvest**

Since the first robotic cholecystectomy was performed in 1997, the da Vinci surgical robot (Intuitive Surgical) has revolutionized the field of minimally invasive surgery. Indeed, use of the robotic platform has become the preferred approach over

#### *Minimally Invasive Surgery in Breast Reconstruction: The Past and Future DOI: http://dx.doi.org/10.5772/intechopen.109503*

laparoscopy for many surgical procedures [15]. By 2018, cadaveric studies and case reports of robotic DIEP flap harvest began to arise in the plastic surgery literature [16]. In 2019, Jesse Selber at the University of Texas MD Anderson Cancer Center published his approach to robotic unilateral DIEP flap harvest [17]. He performs the procedure in a single step although usually delayed from the time of mastectomy. Similar to Kanchwala et al., the perforator is chosen preoperatively based on its short intramuscular course on CT angiography (**Figure 3**). Suprafascial dissection begins in standard fashion with the target perforator isolated and circumferentially dissected down to the posterior sheath via a small fascial incision (**Figure 4**). Robotic ports are then placed through the fascia of the contralateral hemiabdomen and the pedicle is mobilized from an intra-abdominal or transabdominal preperitoneal (TAPP approach) (**Figure 5**). The pedicle is then exteriorized and the fascia closed (Video 1, **Figure 6**).

Other groups have reported success with other approaches including use of a single port site and TEP approach [18, 19]. Many initial case series have focused on unilateral flap harvest; however, surgeons have begun to adapt the technique to allow bilateral flap dissection [20]. A group in Pittsburgh, has presented their technique for bilateral robotic DIEP pedicle harvest using a TAPP approach and 3 8 mm ports placed to target the pelvis. This allows access to both flap pedicles without undocking the robot or placing additional ports. They also report utilizing the da Vinci Firefly fluorescence technology following indocyanine green injection to better visualize the course of the vessels. In their cohort of 10 patients (20 flaps), the mean fascial incision length was 4.5 cm with an average of 1.9 perforators included in the flap design. Mesh was not required to reinforce the abdominal wall in any case. No pedicle or bowel injuries occurred during intraabdominal dissection [21].

## **2.3 Robotic latissimus flap harvest**

For patients who have failed or are not candidates for implant-only reconstruction and who prefer to avoid free-flap breast reconstruction, a pedicled latissimus dorsi (LD) flap often combined with a tissue expander is a viable option for reconstruction. Traditional harvest technique for this flap requires a long posterior incision that

#### **Figure 3.**

*CT angiography identifies dominant DIEP medial perforator (red circle) with minimal intramuscular course. This anatomy makes the patient an ideal candidate for robotic DIEP flap harvest.*

#### **Figure 4.**

*Robotic DIEP flap with perforator dissection performed via 1 cm fascial opening.*

**Figure 5.** *Robotic mobilization of the deep inferior epigastric inferior vessels.*

**Figure 6.** *Abdominal wall after fascial closure following robotic DIEP approach.*

#### *Minimally Invasive Surgery in Breast Reconstruction: The Past and Future DOI: http://dx.doi.org/10.5772/intechopen.109503*

presents an aesthetic challenge for many patients. While this may not be avoidable if a fasciocutaneous flap is used, an unsightly scar can be avoided using minimally invasive techniques if a muscle-only flap is desired.

While endoscopic harvest has been attempted, this approach is constrained by the curvature of the chest wall which limits the ability to maintain satisfactory visualization. More recently, several centers have begun to use the surgical robot for muscle-only LD muscle harvest. The first clinical case series was published by Selber et al. in 2013 [22]. To compete the dissection, three robotic ports are used. One may be placed in an already existing axillary incision if concurrent sentinel node biopsy or axillary node dissection is performed. The anterior border of the muscle is marked. The axillary incision is used to identify and isolate the thoracodorsal artery. Using a lighted retractor, the subcutaneous space anterior to the border of the muscle is opened to allow placement of 2 additional ports. The deep surface of the muscle is dissected first followed by the superficial surface. Finally, the inferior and posterior borders of the muscle are released. Once freed, the flap can be brought up through the axillary incision and transposed into the mastectomy space.

Subsequent reports of robotic latissimus flap harvest have been largely positive. A literature review performed in 2020 identified 32 cases in 5 studies of robotically harvested pedicled LD flaps for implant-based breast reconstruction [23]. All cases were completed successfully without conversion to an open approach. Only 1 study compared complication rates in robotic (n = 12) versus open harvest (n = 64). The authors found a lower rate of complications including seroma, infection, delayed wound healing, and capsular contracture in the robotic group although this was not statistically significant [24]. In all studies, patients were noted to have an excellent aesthetic result.

### **3. Minimally invasive surgery in breast cancer surgery**

As reconstructive surgeons have begun to use minimally invasive surgery to minimize donor site morbidity, breast surgeons have also begun to push the envelope to optimize patient aesthetic concerns.

#### **3.1 Robotic mastectomy**

In 2016, Toesca et al. in Milan, Italy published the first robotic-assisted nipple sparing mastectomy (rNSM) [25]. Their technique utilized a single port with 4 working channels inserted through a 3 cm incision placed in the midaxillary line within the axillary fossa. Through this single site, the entire gland was dissected and implant-based reconstruction performed in either the subpectoral or prepectoral plane.

Since their initial feasibility and safety study, the Milan group has published their outcomes comparing standard nipple sparing mastectomy (sNSM) to rNSM [26]. They performed a randomized non-blinded clinical trial of patients with breast cancer or a genetic predisposition to cancer who were eligible for NSM by standard criteria. Eighty patients were included, 40 in each group. They found that, while rNSM took on average 78 minutes longer to complete compared to sNSM, there were lower rates of surgical complications in the robotic group although this was not statically significant. No ischemic complications were seen in the robotic group while 2 patients in the sNSM group had nipple alveolar complex (NAC) ischemia and 5 had skin flap necrosis. Additionally, Breast-Q scores reflecting satisfaction with breasts, psychosocial, and physical and sexual well-being were significantly higher in the rNSM group.

Other groups have pioneered similar techniques although the use of the surgical robot for mastectomy remains off-label according to the FDA. In response, an expert panel from the International Endoscopic and Robotic Breast Surgery Symposium released a consensus statement to provide guidance regarding the safe practice of robotic mastectomy [27]. The panel sited advantages to the technique including easy visualization and improved surgeon ergonomics. Disadvantages included prolonged operative time and increased cost and limited availability of the surgical platform. They noted the procedure was safe with notably low NAC necrosis rates. They ultimately produced 12 statements to guide patient selection, technique, and selection of surgical, oncologic, and aesthetic outcomes. They conclude that "robotic mastectomy is a promising technique and could well be the future of minimally invasive breast surgery."
