Abstract
The purpose of this study was to describe and analyse the advantages and disadvantages of submandibular gland (SMG) resection using a robotic surgical system through a modified face-lift approach. The authors performed robotic sialoadenectomy of the SMG on 5 patients using the daVinci robot system through a modified face-lift approach. Three robotic arms were inserted through a modified face-lift incision; a face-down 30-degree endoscopic arm and two operative arms. The right arm was equipped with a harmonic scalpel and the left arm with a Maryland forceps. In all patients, robotic sialoadenectomy of the SMG was completed successfully. Diagnoses were sialolithiasis in two patients, pleomophic adenoma in two patients, and ranula in one patient. The mean robotic operative time was 90.2 min (range 62–185 min) and that for setting the robotic system was 8.2 min (range 5–15 min). No significant intra-operative or postoperative complications were observed. All patients were satisfied with the outcome and especially the cosmetic results at their last follow-up visit. In the authors opinion robotic sialoadenectomy of the SMG is technically feasible and secures a better cosmetic outcome than endoscopic submandibular resection.
In the last 20 years, the concept of minimally invasive surgery has opened new research frontiers in the field of surgery. The goal of this research is to adopt surgical techniques that guarantee the same radicality as ‘conventional’ procedures, but that are more acceptable to patients. Since its inception, this area of research has been concerned with benign disease, in which the concept of minimum invasivity is inextricably linked to the reduction of morbidity and aesthetic damage. Concerns about aesthetic result have been significant in procedures involving the head and the neck; regions of the body essential for social interaction.
Endoscopy allowed for the development of techniques that addressed these issues, but its application in head and neck surgery was delayed compared to other areas. The complexity of the anatomical structures and some technical limitations inherent in head and neck surgery have imposed caution in adopting new surgical strategies. The robot, which introduced innovative technological improvements such as three-dimensional magnified vision and an increase in movement excursion, is giving fresh impetus to this field of research. For example, transoral robotic surgery could be confirmed as a valid alternative to conservative treatment of oropharyngeal and hypopharyngeal cancers.
With this in mind, the authors recently tested and refined a robotic resection of the submandibular gland (SMG) using the daVinci robot system (Intuitive Surgical Inc., Sunnyvale, CA, USA) through a modified face-lift approach. The purpose of this study is to describe and analyse the advantages and disadvantages of this technique.
Materials and methods
The Institutional Review Board of Yonsei University approved the protocol to evaluate the feasibility and efficacy of robotic sialoadenectomy in the treatment of submandibular benign pathologies. The inclusion criteria were: 18 years or older at the time of surgery; proximally located salivary calculus, chronic sialoadenitis and benign neoplasms with indication for surgery; and disease not treatable with medications or other conservative procedures. The exclusion criteria were: contraindication for surgery and general anaesthesia due to medical conditions; suspected malignant submandibular neoplasms; and previous treatment on the neck, including surgery or radiation.
From September 2010 to October 2011, the authors performed robotic sialoadenectomy of the SMG on 5 patients. The main clinical features are reported in Table 1 . Patient age ranged from 26 to 41 years (mean 34 years). Preoperative evaluation of the glandular and lesion dimensions were considered through computed tomography (CT) scans, with the aim of considering the feasibility of the surgery. All patients were given detailed information about this technique, and they gave written informed consent for their participation. The authors informed the patients that they could convert to a conventional open approach if any difficult situations were encountered that could not be resolved with robotic surgery. Intraparenchymal sialolithiasis of SMG and benign tumours confined to the SMG were the main indications for this new technique. CT scans were used to evaluate the lesions of all the patients before they underwent surgery. They were followed up for an average period of 8.5 months after the procedure.
| Case | Age | Sex | Diagnosis | Size (cm) | Flap elevation time (min) | Set-up time (min) | Operation time (min) | EBL (ml) |
|---|---|---|---|---|---|---|---|---|
| 1 | 32 | F | Pleomorphic adenoma | 4.1 × 3.5 | 32 | 15 | 85 | Minimal |
| 2 | 26 | F | Sialolithiasis | 4 × 3 | 35 | 9 | 62 | Minimal |
| 3 | 36 | F | Sialolithiasis | 3 × 3 | 29 | 6 | 68 | Minimal |
| 4 | 41 | F | Ranula a | 1.5 × 1 | 37 | 5 | 185 | 15 |
| 5 | 35 | M | Pleomorphic adenoma | 4 × 3 | 33 | 6 | 51 | 5 |
a Submandibular gland was removed together with sublingual gland because of extensive tumour adhesions and involvement of both glandular parenchyma.
Surgical procedure
The patients were placed in the supine position under general anaesthesia. The neck was extended, and the head turned away from the lesion. A 5–6 cm modified face-lift skin incision was made on the lesion side, 5 mm inside the hairline ( Fig. 1 A) . The most important goal at this stage was to preserve the hair follicules surrounding the incision by conducting a perpendicular dissection at the level of the incision until the sternoscleidomastoid and cervical fascia was raised. A supra-platysmal skin flap from the incision to the submandibular region was dissected using an electrical cautery under direct vision ( Fig. 1 B). The most important objective during flap elevation was to preserve the marginal branch of the facial nerve. This goal was easily achieved by lifting of the flap above the platysma.
At the submandibular lodge, the gland was easily identified by the salience that it forms among the surrounding structures. At this point, the platysma was dissected to the level of the inferior margin of SMG and the subplatysmal flap was elevated. Still under direct vision, the posterior pole of the gland was isolated. At this point, if identified, the facial vein would have been cauterized or ligated with harmonic scalpel, also under direct vision. A self-retractor was inserted through the skin incision and the flap was raised using a lifting device to keep a comfortable working space. The daVinci robotic system was set-up. The subsequent manoeuvres would be impossible to perform without the angled magnified robotic vision and without the use of the articulated robotic arms adjustable in directions of space. The patient’s head had been placed on the foot side of the surgical bed and the manipulator cart was positioned 30° apart from the surgical bed. A face-down 30-degree endoscope was inserted through the incision and the two instrument arms were located on both sides of the endoscope ( Fig. 1 C). The right arm was equipped with a harmonic scalpel, the left arm with a Maryland forceps. The operation began when a sufficient view was obtained.
The first step was to dissect the superficial fascia carefully from the SMG capsule. This separation allowed the marginal mandibular branch of the facial nerve to be preserved. The next step was to identify and close the facial artery using the harmonic scalpel and vascular clips at the level of the posterior pole; 2 or 3 clips were positioned proximal to the dissection point, 1 distal ( Fig. 2 A and B) . The facial artery was usually identified between the posterior pole of the gland and the posterior belly of the digastric muscle. Glandular branches of the facial artery were usually ligated with the harmonic scalpel without the use of haemostatic clips. At this point, the posterior surface of the gland had been raised; the posterior belly of the digastric muscle and the hypoglossal nerve had been identified and preserved. The dissection continued until the glandular prolongation and the glandular branch of the lingual nerve with the submandibular ganglion could be identified. This landmark, along with the hypoglossal nerve and the digastric muscle, helped the authors to detect the mylohyoid muscle, the complete identification of which was obtained by dissecting the superior margin of the gland. The mylohyoid muscle could be raised to isolate the lingual nerve, the submandibular ganglion, and its glandular branches. This operation must be performed before resection of the glandular prolongation to prevent the accidental resection of the lingual nerve. Once identified, the resection can be completed without the risk of injuring the lingual nerve ( Fig. 2 C and D). A suction drain was inserted behind the lower end of the hairline incision, and the skin incision was closed tightly with interrupted sutures. The drains were removed within an average of 4.9 days after surgery. Figure 3 shows the SMG specimen.
