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Other clinical studies have suggested that VNGs perform the ansa cervicalis, and the great auricular nerve have
[37]
better in poorly vascularized, [7,31] scarred beds. [32‑35] been the most commonly used NVNGs. In scarred,
irradiated, or to be irradiated fields, functional recovery
WHAT ARE THE INDICATIONS FOR A of the facial nerve can be less satisfactory and VNGs
VNG? have been used for cases with these risk factors. [38‑41]
Although these reports are anecdotal without comparison
It is impossible to establish clear‑cut indications for to NVNGs, there appears to be a consensus for this
[42]
VNGs, as experimental settings fail to replicate actual indication [Table 2].
clinical situations. Having established that VNGs perform The VNGs used are:
better than NVNGs under specific conditions, the clinical
papers available were reviewed. The currently available Vascularized great auricular nerve graft
[41]
literature provides only case reports or case series Koshima et al. used a pedicled 4 cm vascularized
where the indication is based on the surgeon’s judgment ipsilateral great auricular nerve graft for the buccal branch
and experience, rather than on experimental findings. and a nonvascularized sural nerve graft for the zygomatic
However, the surgeon’s judgment and experience are also branch to provide an intrapatient control. They reported
worthy. The current indications for VNG are presented, faster and better recovery for the VNG.
divided into zone of injury. Vascularized lateral femoral cutaneous nerve graft
Vascularized nerve grafts are not indicated in all The lateral femoral cutaneous nerve (LFCN) can be
nerve reconstruction procedures. When a NVNG harvested with an anterolateral thigh (ALT) flap, with a
works well, the additional complexity, and sometimes superficial circumflex iliac artery perforator (SCIP) flap
[43]
morbidity, of the procedure is not justified by superior or alone. Lida et al. reported the first successful
[40]
results. A VNG must be considered in the following use of a free vascularized LFCN graft combined with
scenarios [Table 1]: (1) nerve gaps longer than 6 cm. an ALT flap to repair the facial nerve and a soft tissue
This is an arbitrary and linear measure that does defect, and provided objective measurements of
[44]
not take into the account the diameter of the nerve functional recovery at 14 months (House‑Brackmann
[45]
to be reconstructed. However, the diameter can be grade III/VI, 40‑point grading system: 28/40). Kashiwa
increased with cable grafting; (2) nonvascularized beds; and colleagues described an inferolateral extension
(3) composite defects requiring a free flap. In these of the groin flap based on the vessels accompanying
[46]
cases, the nerve can be included in the free flap with the LFCN for reconstruction of a facial skin and soft
little complexity and no morbidity using the same donor tissue defect including all branches of the facial nerve
site and the nerves directed to the flap; (4) proximal following tumor ablation with nerve gaps of up to
lesions (brachial plexus); (5) long denervation times. 10 cm. The authors did not report any objective data but
The faster reinnervation provided by a VNG might be an noted that facial animation began to return 6 months
advantage in cases that have been referred late and in postoperatively, even in the setting of postoperative
which muscle atrophy has ensued; (6) cases that have to chemotherapy and radiotherapy. They observed that a
undergo radiation therapy which could compromise or relatively “comfortable” result was obtained, aside from
retard the rate of revascularization; and (7) presence of some degree of synkinesis due to misdirection of the
an available donor nerve in the same surgical field which regenerated nerve.
can be harvested without additional morbidity, such as
the pedicled great auricular nerve in facial nerve defects Table 1: Indications for VNGs
during parotidectomies. Nerve gaps longer than 6 cm
Age is a controversial issue as regeneration is worse with Nonvascularized beds
aging, but a more complex procedure might also be less Composite defects requiring a free flap
desirable in the elderly. Because recovery is slower with Proximal lesions (brachial plexus)
age, it might be a relative indication for a VNG. However, Long denervation times
Planned radiation therapy
age alone is not a contraindication to a microsurgical Pedicled VNG available in the same field
procedure, and aged people in good general condition Advanced age
can be considered candidates for a VNG. This applies
especially to motor nerves reconstruction and to late VNG: Vascularized nerve graft
referrals.
In the following sections, clinical indications will be Table 2: Indications for a VNG in facial nerve injuries
reviewed divided by anatomical region in order to provide Vascularized great auricular nerve
a quick reference to those who approach VNG nerve Vascularized LFCN
reconstruction. Vascularized deep peroneal nerve
Vascularized sural nerve
Facial nerve injuries Vascularized motor nerve of the vastus lateralis muscle
Since Balance and Duel first introduced nerve grafting Fascicular turnover method
[36]
for the bridging of facial nerve defects, the sural nerve, VNG: Vascularized nerve grafts, LFCN: Lateral femoral cutaneous nerve

186 Plast Aesthet Res || Vol 2 || Issue 4 || Jul 15, 2015