Journal of Surgical Oncology 2017;115:48–53

Platysma-Sparing Vascularized Submental Lymph Node Flap Transfer for Extremity Lymphedema

1 1 1,2 IGOR POCCIA, MD, CHIA-YU LIN, MSc, AND MING-HUEI CHENG, MD, MBA * 1Division of Reconstructive Microsurgery, Department of Plastic and Reconstructive Surgery, Chang Gung Memorial Hospital, College of Medicine, Chang Gung University, Taoyuan, Taiwan 2Center for Tissue Engineering, Chang Gung Memorial Hospital, Taoyuan, Taiwan

Background and Objectives: Due to its consistent vascular and lymphatic anatomy, the vascularized submental lymph node flap is a reliable option for lymphedema treatment. Despite these advantages, flap harvest requires resection of platysma, which may cause a marginal mandibular nerve pseudo-paralysis. The aim of this study was to investigate the donor site morbidity of an innovative platysma-sparing vascularized submental lymph node flap transfer for treating extremity lymphedema. Methods: Ten patients undergoing platysma sparing submental lymph-node flap harvest were prospectively enrolled in the study and compared with a control group of 10 patients who underwent standard submental lymph-node flap harvest. Photogrammetry analysis was used to assess donor site morbidity with regards to marginal mandibular nerve pseudo-paralysis. Results: All flaps survived. No necrosis of the skin paddle was observed in both groups. There were no marginal mandibular nerve palsies in both group. There were no cases of marginal mandibular nerve pseudo-paralysis in the platysma sparing group. Conclusions: The platysma sparing submental flap, while offering comparable functional improvement for extremity lymphedema, has the advantages of maximizing nerve and muscular preservation, significantly reducing donor site morbidity. J. Surg. Oncol. 2017;115:48–53. ß 2017 Wiley Periodicals, Inc.

KEY WORDS: platysma sparing submental lymph-node flap; vascularized lymph-node transfer; donor site morbidity

INTRODUCTION elevation to include perforating branches from the submental artery and level I lymph nodes. As reported by previous authors, platysma Lymphedema is a chronic and progressive condition that can resection may affect lower lip position during mouth motion [11,12]. severely affects a patient’s quality of life, which is a multidimensional This condition, known as “marginal mandibular nerve pseudo- formula that comprises emotional, functional, social/family, and paralysis,” is caused by a lack of platysma depressive action on physical domains [1]. elevator muscles, giving an asymmetric smile and an elevation of the Recent microsurgical advances in the treatment of lymphedema lower lip [13,14]. promise encouraging results, and vascularized lymph-node transfer is The aim of this study was to describe and investigate the efficacy of becoming quite popular in improving the defective limb drainage [2–6]. an innovative platysma-sparing vascularized submental lymph-node To date, many international groups are studying lymphedema, but flap in preventing the marginal mandibular nerve pseudo-paralysis. standard treatment guidelines remain debatable. Patient selection criteria, timing and type of surgery, donor and recipient sites, and post- operative care are only small parts of the puzzle to be elucidated [7]. PATIENTS AND METHODS A recent meta-analysis investigated the efficacy of vascularized After institutional board approval, 10 consecutive patients lymph-node flap and lympho-venous anastomosis for the treatment of undergoing platysma sparing submental lymph-node flap harvest for lymphedema [8]. It assessed primary outcomes in terms of extremity lymphedema were prospectively enrolled in the study (Group circumference reduction and secondary outcomes in terms of the need for compression garments in the post-operative period. Even though the authors found comparable primary outcomes in both groups, Commercial Asssociations and Financial Disclosures: No funding was when considering secondary outcomes the patients in the vascularized received for this work. lymph node-flap group appeared to fare much better, with a greater Conflicts of interest: The authors do not have any financial interest or likelihood of discontinuing compressive garments in the distal recipient commercial association with subject matter and/or products mentioned in site transfers [8]. the manuscript. Among different options, the vascularized submental lymph-node Level of Evidence: IV (Therapeutic Studies). (VSLN) flap was reported by the senior author for the treatment of lower *Correspondence to: Ming-Huei Cheng, MD, MBA, FACS, Division of extremity lymphedema, and proved to be a reliable and effective lymph Reconstructive Microsurgery, Department of Plastic and Reconstructive node flap [2]. When compared to more traditional approaches such as Surgery, Chang Gung Memorial Hospital, College of Medicine, Chang Gung groin or axillary flaps which may induce iatrogenic lymphedema of the University, 5, Fu-Hsing Street, Kweishan, Taoyuan 333, Taiwan. Fax: þ886-3- donor limb [9–10], the VSLN flap has the benefit of being a safer option. 3972681. E-mail: [email protected]; [email protected] Despite the submental scar is inconspicuous, the anatomy is consistent Received 13 June 2016; Accepted 15 June 2016 and the flap is less bulky when compared to traditional groin lymph DOI 10.1002/jso.24350 fl fl node aps, ap harvest has the potential for injury of the marginal Published online 6 January 2017 in Wiley Online Library mandibular nerve. Furthermore, flap harvest requires platysma (wileyonlinelibrary.com). ß 2017 Wiley Periodicals, Inc. Platysma Sparing Submental Lymph-Node Flap 49

regarding number of lymph nodes, arterial course and diameter, differences between left and right side.

Surgical Technique: Platysma-Sparing Vascularized Submental Lymph Node Flap Harvest Patient positioning. The patient is placed in the supine position with the head hyperextended and slightly laterally flexed on the contralateral side of flap harvest. Pertinent landmarks on the face, which are useful during dissection, are left exposed throughout the procedure. The corner of the mouth and the lower lip helps to visualize the course of the facial nerve and to see whether the lip moves when the nerve is stimulated. Flap design. Preoperative Doppler sonography with an 8 MHz probe provides the location of the submental artery with its cutaneous perforators. An elliptical skin paddle measuring in mean 9 2.5 cm is Fig. 1. Intraoperative flap design and head positioning. An elliptical drawn 1 cm below and parallel to the lower mandibular border, from skin paddle is drawn 1 cm below and parallel to the lower mandibular the angle to the symphysis. A vertical line, 2.5 cm lateral to the oral border. A vertical line, 2.5 cm lateral to the oral commissure, is commissure, is projected on the flap indicating the medial part of projected on the flap indicating the medial part of platysma spared. platysma spared. (Fig. 1). Great care is taken to maintain at least one cutaneous perforator in the lateral portion of the flap. Marginal mandibular nerve preservation. The skin incision starts at the upper margin and descends deep into the platysma only in A) and compared with a control group of 10 patients who underwent the posterior portion of the flap. With the aid of a surgical microscope or standard submental lymph-node flap harvest (Group B). Senior author high magnification loupes, the marginal mandibular nerve is identified MHC treated all patients. underneath the platysma and above the facial artery, usually Patients with a previous history of neck or facial surgery or perpendicular to it. All its branches are identified and confirmed with botulinum injections, with a facial paralysis, and those without full a nerve stimulator. Sharp dissection or the use of electro-cautery, which dentition were excluded from the study. risk nerve damage, are not recommended. Once the marginal Demographic data were analyzed for descriptive analysis. mandibular nerve has been dissected and protected along its course, Each patient inner inter-canthal distance was measured with a the facial artery is ligated distally and dissection continues more vernier caliper and then used for close range photogrammetry. expeditiously. Photogrammetry analysis was performed using Sketch Up Make Platysma-sparing approach. The inferior border of the flap is version 16.1.1451 (2016 Trimble Navigation Limited, Sunnyvale, CA). incised in the same fashion as the upper margin; in the anterior Patients were asked to smile with teeth showing. On frontal view the portion the incision ends in the subcutaneous plane, while, in the pre-operative and post-operative distance between the base of the posterior area it descends deep into the platysma (Video S1). The columella and the position of the lower vermilion at the level of the first anterior portion of the flap is undermined in a subcutaneous plane three maxillary teeth (central incisor I, lateral incisor II, and cuspid III) until the posterior area is reached. At this point, the platysma is spared was bilaterally measured and recorded. Paired Student-t test was used to and the soft tissues and lymph nodes of the anterior portion are prove difference of means in the distance between the operated and the dissected in a pull-through fashion and kept in the flap. Placing skin non-operated sides. hooks and a retractor to elevate the platysma allows a precise and Post-operative analyses were carried out at 12 months follow-up. complete dissection of the soft tissues deep to the medial portion of Statistical analysis was performed using SPSS version 17.0 (Statistical platysma. Dissection continues with meticulous care to preserve Product and Service Solutions, IBM, Armonk, NY), a significance level cutaneous perforators, which are traced through the anterior belly of of 0.05 was used. the digastric muscle. Soft tissue around the junction of the submental artery and the facial artery are included in the flap to ensure the fl Preoperative Imaging preservation of the maximal number of lymph nodes. The ap is dissected away from the submandibular gland. The facial vessels are All patients underwent pre-operative gadolinium enhanced MRI and traced proximally either through or superficial to the gland and the duplex Ultrasonography of the neck. The findings provided data flap is completely elevated (Fig. 2A and B). Video S1 shows the

Fig. 2. (A and B) Donor site after flap harvest demonstrating the preserved platysma in the medial part and the platysma sparing lymph node submental flap. Red arrow displays the artery, blue arrow the facial vein, and yellow arrows two lymph-nodes.

Journal of Surgical Oncology 50 Poccia et al. donor site after flap elevation, and demonstrates the platysma muscle preservation in the submental area along with the marginal mandibular nerve, its contraction and contribution to 1

lower lip motion. Donor site complications 20.7 0 10.5 0 15.6 0 RESULTS a Flap time Demographic data, lymphedema staging, and flap characteristics 0.04 harvesting are presented in Table I [15]. According to preoperative MRI imaging a mean of 3.5 1.9 lymph nodes were transferred for Group 10 114.8 3.2 128.1 6.5 121.5 A while 4.4 1.3 were transferred in Group B. Mean flap dimension

was 90 10 mm in length and 22 3 mm in width. The mean Months min (%) diameter of the facial artery and vein were 2.3 0.4 and 2.5 0.6 mm, respectively. Complications are presented in Table II. All flaps survived, and no necrosis of the skin paddle a 2 15.5 6.2 10.1 15.1 was observed in both groups. There was no donor site morbidity in 12.8 10.7

regard to wound dehiscence, infection, or true marginal nerve 0.04 paralysis (Table II). Interestingly, flap harvesting time was lower in the platysma sparing group. at pre-op MRI Follow-up Photogrammetry study for marginal nerve pseudo-paralysis is Size of lymph node summarized in Table III. For group A, data did not show any statistically significant difference in the position of the lower

vermilion between the operated and non-operated side, proving that a 1.9 26.8 1.3 33.4 1.6 30.1 there were no cases of marginal mandibular nerve pseudo- paralysis.

Out of the 10 patients of group B, 90% had the inferior vermilion at pre-op MRI elevated to the operated side (Table III), with the greatest excursions No. of lymph nodes observed in those patients that strongly rely on platysma for lower lip 0.6 3.5 0.2 4.4 motion. Statistical analysis proves significant differences on the 0.4 4.0

distance between the base of the columella and the vermillion at the Artery level of the first, second, and third tooth with average difference of diameter distance of 1, 1.8, and 1,9 mm, respectively between the non operated 0.7 2.3 0.4 2.3 0.6 2.3 and the operated side (by Student-t test all with P < 0.05), with this Vein differences always tending to vermilion elevation (shorter distance diameter from the columella) on the operated side. However, this finding was a rarely noted as source of complaint from the patients since the lip elevation was in the range of 0–2 mm in 70% of cases (Table II). II:6 (60%) II:5 (50%) Grading of III:1 (10%) III:3 (30%) III:4 (20%) IV:2 (20%) IV:1 (10%) IV:3 (15%) II:11 (55%) DISCUSSION lymphedema The primary concern of the modern reconstructive surgeon should be the accomplishment of the best functional outcome with the least donor site morbidity. Our experience with the submental flap has undergone numerous refinements in the search of the optimal lymph node flap [2–3]. Initially, the flap consisted of a large skin paddle (average 10 5 cm) raised above the mylohyoid plane, sacrificing both the platysma and the anterior belly of the digastric N (%) N (%) N (%) mm mm N mm mellitus Hypertension (Table IV). In an attempt to minimize donor site morbidity, Diabetes subsequent evolution included narrowing the skin paddle and 2 3.6 1 (10%) 5 (50%) I:1 (10%) 2.5 1.4 2 (20%) 4 (40%) I:1 (10%) 2.4 elevating the submental lymph node tissue as a perforator flap, 2.5 3 (15%) 9 (45%) I:2 (10%) 2.5 mass Body sparing the anterior belly of the digastric, and the submandibular index gland. Limitations observed with platysma resection led to an innovative technique that spares the platysma and combines 30.2 24.7 20.1 25.1 harvesting of lymph nodes together with an extra narrow skin 25.2 24.9 paddle (average: 2.5 cm wide) (Table III). Results from our initial Age experience with the platysma sparing flap promise encouraging results in terms both of flap characteristics and donor site related 10 56 morbidity. Interestingly, flap harvesting time was statistically 10 62.1 significant lower in the platysma sparing group. The explanation for this finding is that the senior Author became always more confident with flap anatomy and harvest, thus progressively reducing flap s Grading for extremity lymphedema [15]. harvesting time. ’ While smiling, the angles of the mouth are pulled laterally and sparing VSLN flap flap value 0.06 1 0.06 0.06 0.06 0.07 1 0.05

fi Cheng Group n Years kg/m A: Platysma VSLN, vascularized submental lymph-node. TABLE I. Demographic Data, Lymphedema Staging, and Flap Characteristics a B: Standard VSLN Total (Mean) 20 59.1 upward, and this expression is a ne balance of elevator and P

Journal of Surgical Oncology Platysma Sparing Submental Lymph-Node Flap 51

TABLE II. Complications

Wound Skin Marginal nerve Marginal nerve Group n dehiscence Infection Hematoma Lymphorrhea necrosis paralysis pseudo-paralysisa

A: Platysma sparing VSLN 10 0 0 0 0 0 0 0–1 mm: 100% flap B: Standard VSLN flap 10 0 0 0 0 0 0 0 mm: 10% 0–2 mm: 70% >3 mm: 10% P value 1 1 1 1 1 1 1

VSLN, vascularized submental lymph-node. aExpresses the maximum excursion of the lower vermilion on the operated side.

TABLE III. Photogrammetry Analysis for Evaluation of the Marginal Mandibular Nerve Pseudo-Paralysis

Not-operated side Operated side D Paired T test

Group n. Mean distance mm Mean distance mm Mean distance mm P value

A: Platysma sparing VSLN flap 10 I: 27.6 I:27.4 I: 0.2 I:0.59 II:29 II:29.1 II:0.1a II:0.08 III: 30.9 III:30.7 III:0.2 III:0.59 B: Standard VSLN flap 10 I: 30.8 I:29.8 I:1 I:<0.05 II: 33 II:31.2 II:1.8 II: <0.05 III: 35.4 III:33.5 III:9 III:<0.05

I, II, III, mean distance between the lower vermilion at the level of each of the first three maxillary teeth to the base of the columella; D, excursion of the lower vermilion between the operated and not-operated side; VSLN, vascularized submental lymph-node. aNegative distance: operated side lower than non-operated side.

depressor muscles. The muscles active in this process are the elevators ascertain, but marginal mandibular nerve function can be demonstrated of the lips (levator labii superiors alaeque nasi, elevator labii superiors, by intact mentalis eversion of the lower lip in a symmetrical and the zygomaticus minor), and the depressor of the lips (depressor fashion [14]. An anatomical study investigated the position and angle oris, depressor labii inferioris, mentalis, and platysma). The relation of the depressor anguli oris muscle to bony landmarks and other depressor anguli oris draws the lip downward and laterally, the facial muscles. The authors found that the point at which the lateral depressor labii inferioris everts the vermilion border, and the mentalis border of the depressor anguli oris and the mandibular border meet is acts to protrude the lower lip and wrinkles the skin of the chin. In located 22.6 8.6 mm lateral and 20.8 8.3 mm inferior to the patients with a full-denture smile, the platysma co-functions with the modiolus; at this point, it interlaces with the adjacent platysma and depressors to contribute significantly as a lip depressor [11–12]. this is apparently where it receives its motor contribution [16]. A Ellenbogen was the first author to introduce the “marginal mandibular description of muscular orientation and anatomic relation of depressor nerve pseudo-paralysis” [13]. He assumed that injuring the cervical anguli oris and platysma was carried out also by other authors [17]. It is branch of the facial nerve during dissection would result in a motor clear that the platysma lies deep, inferior, and lateral to the depressor deficit of the lower lip similar to that observed in patients with a muscle. The photogrammetry analysis of both the study and the control marginal mandibular nerve palsy. This condition may be difficult to groups demonstrated that keeping the platysma intact from the midline

TABLE IV. Evolution of the Submental Flap and Differences Among the Traditional, the Perforator, and the Platysma Sparing Flap

VSLN flap VSLN perforator flap VSLN platysma-sparing flap

Skin þþþ Muscle Digastric, þ anterior belly Platysma þþ Lymph-Nodes Level IA þþ Level IB þþþ Advantages • Greatest number of lymph-nodes and • Greatest number of lymph-nodes Minimal donor site morbidity perforators in the flap • Sparing of the anterior belly of the • Sparing of the anterior belly of digastric the digastric • Sparing of the platysma Disadvantages Relatively higher donor site morbidity • Less robust blood supply to the skin • Least robust blood supply to the island skin island • Sacrifice of digastric muscle • Possible “Marginal Mandibular Nerve Pseudo-Paralysis” • Possible “Marginal Mandibular Nerve Pseudo-Paralysis”

VSNL, vascularized submental lymph-node.

Journal of Surgical Oncology 52 Poccia et al.

Fig. 3. (A and B) Pre and post-operative view of a patient while smiling using platysma sparing vascularized submental lymph-node flap transfer. Of note the symmetry of the smile and lower vermilion position.

Fig. 4. (A and B) Post-operative appearence of a patient showing the conceiled donor scar. to a perpendicular line passing 2.5 cm lateral to the corner of the mouth skin paddle in a subcutaneous pocket will promptly result in preserved its pull on the lower lip and proved to be effective to prevent compression of the vein anastomosis. the marginal mandibular nerve pseudo-paralysis in the platysma sparing Dissection of the flap is in a danger zone for the marginal group (Fig. 3A and B). mandibular nerve. Injury to the nerve will cause weakness of the Another concern of VSLN flap is the donor site scar, which may be depressor anguli oris and depressor labii inferioris muscles, leading to visible if poorly planned. However, when the upper margin of the skin asymmetry of the lower lip. Although the precise location of the paddle is placed 1 cm below and parallel to the inferior margin of the marginal branch is variable, its relationship to the superficial mandible, the final scar terminates in a concave and shadowed muscolo-aponeurotic system (SMAS) is constant [22]. The nerve submandibular recess that is inconspicuous in frontal view (Fig. 4A exits the anterior caudal margin of the parotid gland remaining deep and B). Planning the incision in a skin crease is not advisable because to the parotid masseteric fascia and deep cervical fascia. It then those creases do not parallel the inferior border of the mandible. descends inferior to the mandible, and running in a sub-SMAS plane, Furthermore, according to a previous anatomical study, the most it crosses the facial artery [23]. The branches of the facial nerve are reliable perforators arise 3–15 mm below the mandibular border here superficial, small and delicate, making their dissection (average: 7 mm). Consequently, when the skin paddle is narrow potentially precarious. A superior approach and a delicate (<3 cm) and planned too distal from the mandible, there is a strong dissection under an operative microscope represent the best setting likelihood of missing the perforators and also level I lymph nodes. Even to identify and preserve all its branches. While the marginal branch of though the main submental perforator is located 5.5 cm lateral and 3 cm the facial nerve is always exposed during dissection, the cervical inferior to the lateral oral commissure, reliable perforators can be found branch is a rare finding, since its branching point is posterior to the on both borders of the anterior belly of the digastric [18]. Cutaneous flap [24]. However, if exposed during dissection, it must be protected perforators range from one to four, with one perforator piercing the to avoid platysma denervation. platysma and dividing into many branches in the subdermal plane [19]. The ability of such perforators to nourish a skin-only flap is confirmed CONCLUSIONS by one previous report [20] and from our clinical series. These findings fl corroborate the use of a platysma-sparing flap; however, if a narrow skin The submental lymph-node ap has the advantages of a constant paddle (<3 cm wide) is planned, extreme care must be paid to include anatomy, a good number of harvestable lymph-nodes, and a thin and this cutaneous perforator in the flap. pliable skin. The platysma sparing vascularized submental lymph node fl The function of the skin paddle in lymphedema surgery remains ap, while offering comparable functional improvement for extremity unclear. Its use is sporadic, and a review of literature demonstrates lymphedema, has the advantages of maximizing preservation of fi similar encouraging outcomes for a flap with or without a cutaneous marginal mandibular nerve and platysma muscle, signi cantly component [21]. However, it is the authors’ opinion that the skin paddle reducing donor site morbidity. is necessary not only for flap monitoring but also to allow a tension-free closure at the recipient site to avoid compression of the vein REFERENCES anastomosis. The recipient site, especially in the most distal portion 1. Cella DF, Tulsky DS, Gray G, et al.: The functional assessment of of the edematous extremity, has a lack of tissue laxity. With a tangible cancer therapy scale: Development and validation of the general risk of post-operative swelling, insetting a lymph node flap without a measure. J Clin Oncol 1993;11:570–579.

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