Schwannoma de nervio facial con reanimación facial con Neurotizacion Hipoglosofacial / SCHWANNOMA OF THE FACIAL NERVE WITH FACIAL RESUSCITATION WITH FACIAL HYPOGLOSSAL NEUROTIZATION

El schwannoma es una patología rara del nervio facial. Su diagnóstico preoperatorio es dificultoso dado que no tiene síntomas ni signos patognomónico de la enfermedad. La disección del nervio facial en su tronco y sus ramas con electroestimulacion es la forma de quirúrgica de sospecharlo intraoperatoriamente. La descompresión parcial o exeresis completa deberá ser considerado de acuerdo a la experiencia del equipo quirúrgico en reconstrucción nerviosa. La reparación del nervio facial como primera opción debe el injerto inmediato o sutura termino terminal. La neurotización es un procedimiento quirúrgico que le provoca al paciente simetría facial con manejo de oclusión ocular y manejo de comisura bucal, debe ser realizado antes del año de la injuria nerviosa. La rehabilitación del nervio facial necesita de un equipo multidisciplinario y la colaboración permanente del paciente para conseguir los objetivos propuestos.

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 exeresis 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.

Optimal Volume of the Residual Tumor to Predict Long-term Tumor Control Using Stereotactic Radiosurgery after Facial Nerve-preserving Surgery for Vestibular Schwannomas.

BACKGROUND: Intended subtotal resection (STR) followed by adjuvant gamma knife radiosurgery (GKRS) has emerged as an effective treatment option for facial nerve (FN) preservation in vestibular schwannomas (VSs). This study aimed to identify the optimal cut-off volume of residual VS to predict favorable outcomes in terms of both tumor control and FN preservation. METHODS: This retrospective study assessed the patients who underwent adjuvant GKRS for residual VS after microsurgery. A total of 68 patients who had been followed up for ≥ 24 months after GKRS were included. Tumor progression was defined as an increase in tumor volume (TV) of ≥ 20%. House-Brackmann grades I and II were considered to indicate good FN function. RESULTS: The median residual TV was 2.5 cm³ (range: 0.3-27.4). The median follow-up period after the first adjuvant GKRS was 64 months (range: 25.7-152.4). Eight (12%) patients showed tumor progression. In multivariate analyses, residual TV was associated with tumor progression (P = 0.003; hazard ratio [HR], 1.229; 95% confidence interval [CI], 1.075-1.405). A residual TV of 6.4 cm³ was identified as the cut-off volume for showing the greatest difference in progression-free survival (PFS). The 5-year PFS rates in the group with residual TVs of < 6.4 cm³ (54 patients) and that with residual TVs of ≥ 6.4 cm³ (14 patients) were 93.3% and 69.3%, respectively (P = 0.014). A good FN outcome was achieved in 57 (84%) patients. Residual TV was not associated with good FN function during the immediate postoperative period (P = 0.695; odds ratio [OR], 1.024; 95% CI, 0.908-1.156) or at the last follow-up (P = 0.755; OR, 0.980; 95% CI, 0.866-1.110). CONCLUSION: In this study, residual TV was associated with tumor progression in VS after adjuvant GKRS following STR. As preservation of FN function is not correlated with the extent of resection, optimal volume reduction is imperative to achieve long-term tumor control. Our findings will help surgeons predict the prognosis of residual VS after FN-preserving surgery.

Facial Nerve Indentation in Hemifacial Spasm: An Analysis of Factors Contributing to the Formation of and Consequent Effects Associated with Indentation.

BACKGROUND: An indentation, designating a furrowed hole on the facial nerve, has been used in many studies for locating pathophysiology and assessing relevant clinical outcomes after microvascular decompression for hemifacial spasm (HFS). In this study, we sought to elucidate the contributing factors forming indentation on the facial nerve and the consequent effect of having indentation on the clinical course. METHODS: We divided the patients into 2 groups: group A, the patients who had no indentation on the root exit zone of the facial nerve; and group B, the patients who had an indentation. Demographic data, intraoperative findings, and clinical outcomes were analyzed from retrospective review of the medical records. RESULTS: Of the 132 patients, 47.0% had an indentation on the facial nerve. Our statistical analyses showed that the preoperative symptom period, compression location, and compression pattern were associated with the occurrence of the indentation. Also, we showed that HFS reappearance developed more frequently in patients in group B, who needed more time for the resolution of HFS. The final clinical outcome was less influenced by the existence of the indentation, although it was slightly poorer for group B than for group A. CONCLUSIONS: The indentation on the facial nerve was associated with longer duration of symptoms, the presence of compression in the proximal segment of the root exit zone, and loop-type pattern of compression. More patients with indentation experienced the HFS reappearance phenomenon, which lasted longer than in those who had no indentation.

Primary facial nerve paraganglioma: report and review of the literature.

This report describes the diagnosis and treatment of a patient with a rare primary facial nerve paraganglioma as well as a review of the current literature. A 60-year-old male patient presented to our clinic with a 4-month history of left-sided progressive facial paralysis House-Brackmann V. Biopsy taken during facial nerve (FN) decompression confirmed the diagnosis of paraganglioma. The left FN was sacrificed during resection of the mass and a 12-7 jump graft, using the left greater auricular nerve, was performed with acceptable outcomes. The rarity of these tumours does not discount their clinical importance or the necessity to include them in the differential when presented with unilateral FN paralysis. Investigation should begin with CT and MRI imaging to identify and localise the potential mass. Histologic confirmation requires tissue. While surveillance imaging is occasionally an option, often complete surgical resection of the mass and sacrifice of the nerve is necessary.

Optic, trigeminal, and facial neuropathy related to anti-neurofascin 155 antibody.

OBJECTIVE: To characterize the frequency and patterns of optic, trigeminal, and facial nerve involvement by neuroimaging and electrophysiology in IgG4 anti-neurofascin 155 antibody-positive (NF155+ ) chronic inflammatory demyelinating polyneuropathy (CIDP). METHODS: Thirteen IgG4 NF155+ CIDP patients with mean onset age of 34 years (11 men) were subjected to neurological examination, blink reflex, and visual-evoked potential (VEP) testing, and axial and/or coronal T2-weighted head magnetic resonance imaging (MRI). RESULTS: Among 13 patients, facial sensory impairment, facial weakness, and apparent visual impairment were observed in three (23.1%), two (15.4%), and two (15.4%) patients, respectively. All 12 patients tested had blink reflex abnormalities: absent and/or delayed R1 in 11 (91.7%), and absent and/or delayed R2 in 10 (83.3%). R1 latencies had strong positive correlations with serum anti-NF155 antibody levels (r = 0.9, P ≤ 0.0001 on both sides) and distal and F wave latencies of the median and ulnar nerves. Absent and/or prolonged VEPs were observed in 10/13 (76.9%) patients and 17/26 (65.4%) eyes. On MRI, hypertrophy, and high signal intensity of trigeminal nerves were detected in 9/13 (69.2%) and 10/13 (76.9%) patients, respectively, whereas optic nerves were normal in all patients. The intra-orbital trigeminal nerve width on coronal sections showed a significant positive correlation with disease duration. INTERPRETATION: Subclinical demyelination frequently occurs in the optic, trigeminal, and facial nerves in IgG4 NF155+ CIDP, suggesting that both central and peripheral myelin structures of the cranial nerves are involved in this condition, whereas nerve hypertrophy only develops in myelinated peripheral nerve fibers.

Epineurial Pseudocyst of the Intratemporal Facial Nerve: A Case Series Study.

OBJECTIVES: The goal of this case series was to describe the clinical and radiological characteristics of epineurial pseudocysts of the intratemporal facial nerve (EPIFs) and to discuss the relevance in clinical practice. MATERIALS AND METHODS: A retrospective case series of 10 consecutive patients with EPIFs identified through computed tomography (CT), between 2009 and 2018. Morphological characteristics, coexisting pathology, facial nerve function, and evolution over time were analyzed. RESULTS: A unilateral EPIF was found in 5 patients (50%) and a bilateral EPIF was found in the other 5 (50%). The largest dimensions were observed in the coronal plane, with an average craniocaudal length of 6.0 mm (range, 3-9 mm). None of the patients presented with facial nerve dysfunction. Growth could not be observed in any of the patients. In 5 cases (33.3%), CT imaging showed a reduced transmastoid access to the facial recess caused by the EPIF. CONCLUSION: All EPIFs in this study were incidental findings. Facial nerve function was normal in all patients. Knowledge of EPIFs is important to perform safe cholesteatoma and cochlear implant surgery and to prevent unnecessary follow-up imaging.

Effect of Anatomic Segment Involvement on Stereotactic Radiosurgery for Facial Nerve Schwannomas: An International Multicenter Cohort Study.

BACKGROUND: Facial nerve schwannomas are rare, challenging tumors to manage due to their nerve of origin. Functional outcomes after stereotactic radiosurgery (SRS) are incompletely defined. OBJECTIVE: To analyze the effect of facial nerve segment involvement on functional outcome for these tumors. METHODS: Patients who underwent single-session SRS for facial nerve schwannomas with at least 3 mo follow-up at 11 participating centers were included. Preoperative and treatment variables were recorded. Outcome measures included radiological tumor response and neurological function. RESULTS: A total of 63 patients (34 females) were included in the present study. In total, 75% had preoperative facial weakness. Mean tumor volume and margin dose were 2.0 ± 2.4 cm3 and 12.2 ± 0.54 Gy, respectively. Mean radiological follow-up was 45.5 ± 38.9 mo. Progression-free survival at 2, 5, and 10 yr was 98.1%, 87.2%, and 87.2%, respectively. The cumulative proportion of patients with regressing tumors at 2, 5, and 10 yr was 43.1%, 63.6%, and 63.6%, respectively. The number of involved facial nerve segments significantly predicted tumor progression (P = .04). Facial nerve function was stable or improved in 57 patients (90%). Patients with involvement of the labyrinthine segment of the facial nerve were significantly more likely to have an improvement in facial nerve function after SRS (P = .03). Hearing worsened in at least 6% of patients. Otherwise, adverse radiation effects included facial twitching (3 patients), facial numbness (2 patients), and dizziness (2 patients). CONCLUSION: SRS for facial nerve schwannomas is effective and spares facial nerve function in most patients. Some patients may have functional improvement after treatment, particularly if the labyrinthine segment is involved.

Schwannoma of the Greater Superficial Petrosal Nerve: An Unusual Site for a Common Tumor.

Greater superficial petrosal nerve (GSPN) schwannoma is a rare clinical entity. It forms a small subset of the larger group of facial nerve schwannomas. A thorough literature search yielded only 27 such cases reported to date in the English literature. We present one such rare case of GSPN schwannoma and discuss the clinical spectrum and management along with a review of the literature. We demonstrate the surgical steps in an operative video.

Cerebellopontine angle schwannomas arising from the intermediate nerve: a scoping review.

Intermediate nerve schwannomas (INS) are extremely rare lesions in literature. They have been described mimicking facial nerve schwannomas, but not vestibular schwannomas (VS). We aimed to review the previously published cases, as well as the evidence to believe that they are far more common, though usually misdiagnosed as facial or VS. We performed a review of PubMed/Medline and Embase of "intermediate nerve schwannoma," "facial nerve schwannoma," "greater superficial petrosal nerve schwannoma," "geniculate ganglion schwannoma," and "chorda tympani schwannoma" to identify all cases of INS, following the Preferred Reporting Items for Systematic reviews and Meta-Analyses extension for Scoping Reviews (PRISMA-ScR) statement. Furthermore, 2 cases operated at our center are shown to exemplify the proposed hypotheses. No article was excluded from review. Thirteen cases of INS, 11 cases of chorda tympani schwannoma, and 18 cases of greater superficial petrosal nerve schwannoma were found in literature. In facial nerve schwannomas, the predilection of schwannomas for sensory nerves, and the ability to preserve the motor facial nerve during tumor resection support the hypothesis of intermediate nerve as the nerve of origin. For VSs, the different arachnoidal arrangement of medial VS, the sharing of pia mater by the intermediate nerve and vestibular nerve, and the medial Obersteiner-Redlich zone of the intermediate nerve, support the hypothesis of intermediate nerve origin of some VS. The correct identification of the intermediate nerve as a nerve of origin of cerebellopontine angle schwannomas is of uttermost importance, especially when mistaken for VS, as this may account for the heterogeneity of facial and cochlear outcomes after surgery.

Amphiphysin-IgG autoimmune neuropathy: A recognizable clinicopathologic syndrome.

OBJECTIVE: To define the clinicopathologic features of amphiphysin-immunoglobulin G (IgG)-mediated neuropathy. METHODS: Patients examined at our institution from January 1, 1995, to September 30, 2018, with amphiphysin-IgG by indirect immunofluorescence and Western blot, were reviewed. Their phenotypes were compared to cases of coexisting collapsin response-mediator protein-5 (CRMP5)-IgG or anti-neuronal nuclear antibody type 1 (ANNA1-IgG) and CRMP5-IgG autoimmunity. Improvement in modified Rankin Scale (mRS) (≥1) on follow-up was considered a favorable outcome. Amphiphysin RNA expression was assessed in healthy nerves. RESULTS: Fifty-three amphiphysin-IgG-positive cases were identified. Of 33 (60%) patients with neuropathy, 21 had amphiphysin-IgG alone, and 12 had coexisting autoantibodies (ANNA1-IgG, n = 8; CRMP5-IgG, n = 2; ANNA1-IgG and CRMP5-IgG, n = 2). The neuropathies in isolated amphiphysin-IgG autoimmunity included polyradiculoneuropathy (62%), diffuse sensory neuronopathy (35%), and facial neuropathy with gastroparesis (3%). Among these, pain (80%), breast cancer (63%), and CNS (57%) involvements commonly coexisted, and neuropathy frequently prompted breast cancer diagnosis (76%). Stiff-person spectrum disorder was the most common CNS accompaniment (45%). Nerve biopsies showed axonal loss (n = 6/6), subperineurial edema (n = 4/6), and CD4 predominant inflammation (n = 2/6). Median mRS score at last follow-up was 3.5; 58% of patients were immunotherapy-responsive. Patients with amphiphysin-IgG alone had more favorable immunotherapy response than patients with CRMP5-IgG polyneuropathy (n = 45) (44% vs 16%, p = 0.028, odds ratio 4.2, 95% confidence interval 1.1 to 15.5). Only 1/9 (11%) patients with amphiphysin-IgG with coexisting CRMP5-IgG or ANNA1-IgG had immunotherapy response. RNA amphiphysin expression occurred at low levels in nerve. CONCLUSION: Amphiphysin-IgG autoimmune neuropathy has a recognizable phenotype, is frequently immune responsive, and can prompt early diagnosis of breast cancer.

Tympanic-mastoid and parotid schwannomas of the facial nerve: clinical presentation related to the anatomic site of origin.

Objective: To describe the clinical presentation of the facial nerve schwannomas according to the anatomical site of origin. Method: A retrospective study in which the clinical presentation, diagnostic protocol and treatment of facial nerve tumors in adults was evaluated. Results: We found 6 cases, 4 cases of tympanic-mastoid location at the spectrum of its possible clinical presentation: from symptomatic cases with facial paralysis, to an asymptomatic case in the tympanic portion found as intraoperative finding; and also found two cases located at the parotid gland, one with complete facial paralysis and one without facial palsy. Conclusions: For the diagnosis of intratemporal and parotid schwannomas of the facial nerve, a high clinical suspicion is required given its heterogeneous presentation; its clinical course depends on the segment of origin and expansion: more frequently asymptomatic at the tympanic horizontal portion and symptomatic at the mastoid vertical portion. These tumors must be assessed with imaging studies, incisional biopsy is not recommended. The treatment is surgical resection in symptomatic patients with facial paralysis greater than grade III of House-Brackmann, with immediate reconstruction of the nerve.

Objetivo: Describir la presentación clínica de los schwannomas del nervio facial de acuerdo con el sitio anatómico de origen. Método: Se realizó un estudio retrospectivo en el que se evaluó la presentación clínica, el protocolo diagnóstico y el tratamiento de tumores del nervio facial en adultos. Resultados: Se encontraron seis casos, cuatro de ellos de localización tímpano-mastoidea en los extremos de su posible presentación clínica: desde casos sintomáticos con parálisis facial, hasta un caso asintomático de la porción timpánica encontrado como hallazgo transoperatorio; y se encontraron dos casos de localización parotídea, uno con parálisis facial completa y otro sin parálisis facial. Conclusiones: Para el diagnóstico de tumores intratemporales y parotídeos del nervio facial se requiere una elevada sospecha clínica dado lo heterogéneo de su presentación; su curso clínico depende del segmento de origen y de su extensión: más frecuentemente son asintomáticos los de la porción timpánica y son sintomáticos los de la porción mastoidea. Estos tumores deben evaluarse con estudios de imagen; no se recomienda realizar biopsia incisional. El tratamiento es la resección quirúrgica en los casos sintomáticos con parálisis facial de grado IV o mayor de House-Brackmann, con reconstrucción inmediata del nervio.

A Rare Case of Adenoid Cystic Carcinoma Isolated in the Mastoid.

Adenoid cystic carcinoma (ACC) isolated in the mastoid is very rare. Its diagnosis, especially in the early stage, is often challenging as during that stage, the signs and symptoms may be nonspecific. Our paper describes a case of a patient with an isolated mass in the left mastoid with persistent peripheral facial paralysis, and this was initially diagnosed as facial neuritis and granulation. However, histological examination later revealed an ACC exhibiting tubular and cribriform patterns. Our paper discusses the diagnostic basis, treatment, and outcomes for this case to improve the understanding of ACC isolated in the mastoid.

Granular cell tumor of the trunk of the facial nerve: A case report.

RATIONALE: Granular cell tumor (GCT) is a relatively uncommon, usually benign lesion that often presents as a solitary, painless cutaneous or submucosal nodule. GCTs of the head and neck are not uncommon; however, involvement of the trunk of the facial nerve is rare. PATIENT CONCERNS: A 55-year-old woman presented a lesion at the posterior border of the left parotid gland. Doppler ultrasound revealed a hypoechoic mass and magnetic resonance imaging disclosed an irregularly shaped lesion with unsharp borders in the posterior aspect of the left parotid gland that was hyperintense on T2-weighted images and enhancing with contrast on T1-weighted images. The remainder of the parotid gland was normal. DIAGNOSIS: Following excision of the mass, diagnosis of a GCT was established and confirmed by immunohistochemistry. INTERVENTIONS: The patient underwent surgical excision of the lesion. OUTCOMES: The patient is currently asymptomatic and without recurrence after 10 months follow-up. LESSONS: GCT involvement of the trunk of the facial nerve is rare. Immunohistochemical staining is helpful for its diagnosis.

Microglia lacking a peroxisomal ß-oxidation enzyme chronically alter their inflammatory profile without evoking neuronal and behavioral deficits.

BACKGROUND: Microglia play a central role in most neurological disorders, but the impact of microgliosis on brain environment and clinical functions is not fully understood. Mice lacking multifunctional protein-2 (MFP2), a pivotal enzyme in peroxisomal ß-oxidation, develop a fatal disorder characterized by motor problems similar to the milder form of MFP2 deficiency in humans. The hallmark of disease in mice is the chronic proliferation of microglia in the brain, but molecular pathomechanisms that drive rapid clinical deterioration in human and mice remain unknown. In the present study, we identified the effects of specific deletion of MFP2 from microglia in the brain on immune responses, neuronal functioning, and behavior. METHODS: We created a novel Cx3cr1-Mfp2-/- mouse model and studied the impact of MFP2 deficiency on microglial behavior at different ages using immunohistochemistry and real-time PCR. Pro- and anti-inflammatory responses of Mfp2-/- microglia were assessed in vitro and in vivo after stimulation with IL-1ß/INFγ and IL-4 (in vitro) and LPS and IL-4 (in vivo). Facial nerve axotomy was unilaterally performed in Cx3cr1-Mfp2-/- and control mice, and microglial functioning in response to neuronal injury was subsequently analyzed by histology and real-time PCR. Finally, neuronal function, motor function, behavior, and cognition were assessed using brainstem auditory evoked potentials, grip strength and inverted grid test, open field exploration, and passive avoidance learning, respectively. RESULTS: We found that Mfp2-/- microglia in a genetically intact brain environment adopt an inflammatory activated and proliferative state. In addition, we found that acute inflammatory and neuronal injury provoked normal responses of Mfp2-/- microglia in Cx3cr1-Mfp2-/- mice during the post-injury period. Despite chronic pro-inflammatory microglial reactivity, Cx3cr1-Mfp2-/- mice exhibited normal neuronal transmission, clinical performance, and cognition. CONCLUSION: Our data demonstrate that MFP2 deficiency in microglia causes intrinsic dysregulation of their inflammatory profile, which is not harmful to neuronal function, motor function, and cognition in mice during their first year of life.

Facial onset sensory and motor neuronopathy: a motor neuron disease with an oligogenic origin?

Objective: To describe a patient with facial onset sensory and motor neuronopathy (FOSMN) carrying heterozygous mutations in both TARDBP and SQSTM1 genes. Methods: The patient underwent neurological, neuropsychological, and neurophysiological examinations. Brain magnetic resonance imaging (MRI) and extensive genetic analysis were also performed. Results: The neurological examination showed dysphonia, left trigeminal hypesthesia, and left masseter and temporalis muscle atrophy. Mild cognitive impairment, affecting predominantly executive functions and social cognition, was appreciable in the neuropsychological examination. The electrophysiological studies revealed: left abnormal blink reflex; neurogenic changes in bulbar and cervical muscles; normal motor evoked potential amplitude, central motor conduction time and cortical silent period. Brain MRI showed right-predominant frontotemporal atrophy. Genetic analysis showed a heterozygous mutation in TARDBP (p.A390S) and in SQSTM1 (p.P392L), both previously described as causing amyotrophic lateral sclerosis. The SQSTM1, but not the TARDBP, mutation was found in both healthy siblings. Conclusions: Our data provide new clinical, neuroimaging, and genetic evidence that FOSMN is a neurodegenerative disease of the motor neuron disease and frontotemporal dementia spectrum, with a possible oligogenic origin. Multicentric efforts focusing on cognitive and genetic studies are necessary to confirm this hypothesis and to determine if ALS genes should be systematically screened in these patients.

Intraparotid facial nerve schwannoma: a 17-year, single-institution experience of diagnosis and management.

BACKGROUND: Intraparotid facial nerve schwannoma (IFNS) is rare and its definite preoperative diagnosis is challenging. OBJECTIVE: To improve available knowledge regarding the diagnosis of IFNS and to suggest an appropriate treatment plan. MATERIAL AND METHODS: We retrospectively analyzed medical records of IFNS patients at our hospital. Inclusion criteria were surgery (from January 2000, to December 2016) for a parotid mass, pathologically diagnosed as a schwannoma. RESULTS: The study included 42 eligible patients who had undergone tumor resection from 5977 parotid tumor patients. Mostly presented hard-textured (18/39) or medium-textured (15/39), with limited mobility (21/39) mass (three tumors were not palpable). Their facial nerve function outcomes were House-Brackmann Grade I (n = 14), Grade II (n = 7), Grade III (n = 11), Grade IV (n = 5), Grade V (n = 3), and Grade VI (n = 2). Significant differences were noted in results based on different surgical methods used (p = .000) and tumor involvement (p = .002). CONCLUSIONS AND SIGNIFICANCE: A hard-textured tumor with limited mobility mass in the parotid gland should prompt the diagnosis of a schwannoma. Tumors involving main trunk usually lead to unsatisfactory facial nerve outcomes. Facial nerve preservation should always be essential, and stripping surgery or intracapsular enucleation could be the preferred surgical methods of choice.