Schwannoma is a rare pathology of the facial nerve. Its preoperative diagnosis is difficult since it has no symptoms or pathognomonic signs of the disease.
The dissection of the facial nerve in its trunk and its branches with electrostimulation is the surgical way to suspect it intraoperatively. Partial decompression or complete exercises should be considered according to the experience of the surgical team in nerve reconstruction.
The repair of the facial nerve as a first option should be the immediate graft or end-to-end suture.
Neurotization is a surgical procedure that causes the patient facial symmetry with management of ocular occlusion and management of the corner of the mouth, it must be performed within a year of the nerve injury.
The rehabilitation of the facial nerve requires a multidisciplinary team and the permanent collaboration of the patient to achieve the proposed objectives.
Schwannoma, Facial Nerve, Facial Resuscitation, Facial Hypoglossal Neurotization
Schwannomas (also called neurilemomas) of facial nerve is a benign tumor that arises from Schwann cells, from the neural sheath of the peripheral, sensitive or sympathetic and sympathetic nerve nerves and in cranial nerve, except for the optical and olfactory nerves Cranials that lack Schwann cell pod.
Extra cranial neurilemomas 25-45% occur in the head and neck. Being the extra cranial location cervical Latero the most frequent, the most frequent intracranial neurilemoma is acoustic neurinoma (Iix nerve). Facial Schwannoma are extra cranial neurilemoma that is presented as a parotid mass of slow and painless growth. The presentation arises in the third or fourth decade of life, preferably in the female sex.
The preoperative diagnosis is difficult, the PAAF only has 40% sensitivity, it can exclude other parotid tumors. Tomography guides us to the location of tumor and NMR shows ISOINTENSE mass to the muscle in T1 and hyperincent to the muscle in T2 with a weak intensity in the center that becomes greater towards the periphery “sign of the Diana”.
In 1910 Verocay first described a group of neurogenic tumors to what he referred to as a neurinoma. In 1920 Antoni described two histological patterns characterized by hypercellularity and myxoid. In 1935 it was proposed that these tumors originate from the nerve sheaths called neurilemomas.
The definitive diagnosis is performed by biopsy, finding double histological pattern with antoni a and b areas, the areas of Antoni A are fusiform cells with nuclei arranged in palisades separated by the extensions of the Schwann cells originating the Verocay bodies in the pattern hypercellular The Antoni B type area is hypocellular with myxoid stroma with blood vessels and inflammatory cells.
The malignant degeneration of tumor is rare, the removal of the lesion is the treatment of choice. The recurrence is rare. The damage of major nerve trunks should be considered for immediate repair by means of terminals of the nerve or immediate nerve graft.
Facial nerve preservation during tumor resections in the different portions of its journey is a great concern on the part of the surgical team.
The rehabilitation of facial paralysis will depend on the intraosea (intracranial) or peripheral (extra cranial) location, on the condition of the wound, of the time elapsed by the lesion, a state of degree of muscle atrophy, the technical possibilities of reconstruction and psychological states - patient’s mood.
Facial nerve repair can be performed by various techniques, passive techniques are the most used, but it is the dynamic techniques that allow it to recover ocular occlusion, oral occlusion and social smile.
The ipolateral neurorraph consists of the approximation of the nerve ends directly or with an interposition of nervous graft preferably of the major atrial nerve or the skin to the electrical stimuli of the nerve ends.
Cross nerve grafts consist in the interposition of nervous graft from the branches of the facial nerve to function to the nerve branches do not work, the movements are synchronized and symmetrical. It must be done before three months of nerve injury [1,2].
Neurotization consists of nerve anastomosis. As a disadvantage, it presents morbidity in the donor nerve area, tongue atrophy, swallowing (hypogloso), winged scapula (spinal), loss of chewing force (trigeminal). The other disadvantage that presents is the movement the lack of coordinated movement.
The advantages that these procedures present allow partially recovering the affected function and favoring the psychological, social and labor reintegration of patients.
The rehabilitations of these patients require a multidisciplinary team composed of head and neck surgeon, plastic surgeon, neurosurgeon, physiotherapist and the patient’s collaboration to complete the exercises in their home, to understand the times that takes the neurological recovery of the facial nerve.