Turbocharging of Deep to Superficial Venous System for Vessel Depleted Neck in Radial Forearm Free Flap: A Case Report of One Neck Vein for Drainage of Both Venous Systems
Article information
Abstract
Dual venous anastomosis in radial forearm free flap surgery increases chances of flap survival as compared to anastomosing only the superficial system. A 48-year-old male patient who had received three previous microsurgical reconstructions and radiotherapy presented with recurrent oral cavity carcinoma. Two of these reconstructions were anastomosed to the left side neck vessels. The recurrence was in the left half of the soft palate. The left neck and underlying vessels were severely scarred and fibrotic, and only 2 cm of the left internal jugular vein (IJV) could be circumferentially mobilized for anastomosis, allowing for only one venous anastomosis. The radial forearm free flap was harvested and a tributary of the cephalic vein was preserved in the proximal part to act as a conduit for drainage of one of the venae comitantes. The cephalic vein was anastomosed end-to-side to the IJV and one venae comitantes to the preserved tributary in end-to-end fashion. The flap survived and the patient was discharged in a week. This novel method helps to drain both venous systems through one available neck vein.
Introduction
The radial forearm flap is a commonly used free flap for reconstruction [1]. Its thin pliable skin cover along with the long pedicle make it an ideal flap for reconstruction in the head and neck region, especially in vessel depleted or “frozen” necks with paucity of vessels [2]. The flap is drained by both superficial and deep venous systems. It is already well-known that the risk of venous congestion decreases when both systems are anastomosed compared to when only the superficial system is utilized for venous drainage [3]. However, this method of dual anastomosis is sometimes not possible, especially in recurrent tumors when previous neck dissection and microsurgical reconstruction procedures have depleted the recipient vessels [4]. We present our method of dual system drainage using a single neck vein by turbocharging a deep vein into a superficial vein, reducing the chances of flap loss. Written informed consent was obtained from the patient for this publication including photographic findings.
Idea
A 48-year-old male presented with carcinoma of the left half of the soft palate (Fig. 1). He had previously undergone three microsurgical reconstructions in the past 8 years for recurrent oral cancers along with adjuvant chemoradiotherapy. Details of the previous surgical procedures are presented in Table 1. Two of these previous free flaps were anastomosed to the left side neck vessels. This time, a lip-splitting incision was used to expose the tumor as the patient’s mouth opening was severely restricted. After resection of the malignancy, the resulting defect involved the soft palate and tonsillar fossa (Fig. 2).
Recurrent oral cancer involving the soft palate.
Details of microsurgical reconstructions
Lip-splitting incision with resection defect and dissected neck vessels.
The neck was explored for vascular anastomosis. It took more than an hour to prepare suitable recipient vessels as the “frozen” left neck area was severely scarred and fibrotic. The left lingual artery was dissected from the scar tissue, but only 2 cm of the internal jugular vein (IJV) could be mobilized circumferentially for end-to-side anastomosis as the extensively scarred perivascular tissue endangered further dissection which could cause catastrophic vein injury.
The secured length of the IJV was just enough for one anastomosis and hence to drain both venous systems, internal drainage of the radial artery venae comitantes to the cephalic vein was planned. During flap harvesting, a stump of a draining tributary of the cephalic vein was preserved in the proximal part of the vein (Fig. 3). The flap was inset in the defect, and after arterial anastomosis, venous return was confirmed in both systems. The cephalic vein was anastomosed to the dissected IJV in an end-to-side fashion and one of the venae comitantes of the radial artery was anastomosed to the tributary stump in end-to-end fashion (Figs. 4, 5). The flap survived completely and the patient was discharged in a week after surgery (Fig. 6).
Harvested flap with preserved proximal tributary marked with arrow.
Intraoperative view of anastomosed vessels. Cephalic vein (CV), tributary of cephalic vein (TRI), radial artery (RA), and venae comitantes (VC).
Line diagram of anastomosed vessels.
Well taken flap at postoperative 1 year.
Discussion
Since its introduction, the radial forearm flap has been a workhorse flap for microsurgical reconstruction of not only the extremities but also in head and neck cases [5]. The long pedicle of the radial forearm free flap is an added advantage over other flaps which eases anastomosis to remote vessels in recurrent head and neck tumors, especially those that require anastomosis to the contralateral neck vessels. However, though the arterial anatomy is straightforward, there is controversy regarding the dominant venous drainage [6].
The number of venous anastomoses required for flap safety is another matter of debate. Many surgeons prefer to anastomose only the cephalic vein as it is of larger diameter and hence technically less demanding [7]. Others prefer to anastomose both superficial and deep systems to two different recipient veins as the chances of venous congestion in patients with dual anastomosis is less than those who have only the superficial venous system for flap drainage. Kim et al. [3] analyzed the chances of venous congestion and flap loss in patients having single vs double anastomosis. They concluded that the risk of venous congestion is lower in patients with dual system drainage compared to patients who had only superficial venous anastomosis. Hemodynamic studies demonstrate that the deep veins drain double the amount of blood as compared to cephalic veins; the main physiological venous return from the flap is via the deep venous system and thus it should be anastomosed in priority [8].
The issue with recurrent cases is the steep increase in complexity every time the neck is explored for anastomosis [9]. Every surgical procedure becomes more challenging and every flap more precarious, hence all available measures should be implemented to reduce the chances of flap failure.
We too prefer to anastomose both the cephalic vein and one of the radial artery venae comitantes in the radial forearm free flap. With previous neck dissections, microsurgical reconstruction and radiotherapy leading to a vessel depleted neck, the chances of procuring multiple veins for dual anastomosis is sparse. Although the IJV can safely be used as a solitary recipient vein for drainage of a new free flap, circumferential dissection of the vein is essential for end-to-side anastomosis. Scarring from previous procedures makes atraumatic dissection of the IJV for anastomosis exceedingly more difficult. Even a small rent in the IJV requires repair and this might further compromise the success of anastomosis, especially if done in proximity to the anastomosis site.
Though anastomosis to the contralateral neck vessels may be a safe alternative, this may require a vein graft. Cephalic vein transposition is a useful method to tide over this situation where the cephalic vein is dissected in the proximal arm and rerouted to reach the neck [10]. Our method, which involved internal drainage of the venae comitantes to the cephalic vein, drains both systems to an IJV with limited access IJV through a single neck vein anastomosis. This internal drainage can be performed before detaching the flap from the forearm, although we prefer doing it after transferring the flap to the recipient site so that the pedicle positioning and placement of all three vascular structures are well aligned. One more method for single venous anastomosis in the neck is to dissect the venae comitantes proximally in the forearm (during flap harvest) up into the antecubital fossa where the venae comitantes joins the cephalic vein through the medial cubital vein [11]. This provides one large vein draining both systems. But in most cases such a long pedicle is not required and this extensive dissection can be avoided by using our technique. If the IJV can be circumferentially mobilized comfortably, both venous systems can be individually anastomosed to the IJV in end-to-side fashion. But in this patient, due to severe scarring and fibrosis of surrounding structures, the IJV could be mobilized only enough to accommodate one anastomosis.
In conclusion, this method of internal drainage of the deep venous system through the superficial system helps in confidently transferring radial forearm free flaps where the margin of error and chances for another flap are minimal.
Notes
No potential conflict of interest relevant to this article was reported.