Síndrome de Moebius y ortotropía en posición primaria: ¿es infrecuente esta asociación? (Colombia) / Moebius syndrome and orthotropia in primary position: is this association uncommon? (Colombia) / Síndrome de Moebius e ortotropia em posição primária: é uma associação incomum? (Colômbia)

El síndrome de Moebius es una enfermedad congénita poco común que se caracteriza por el compromiso unilateral o bilateral del VI y VII par craneal, lo que compromete los músculos que controlan la oculomotricidad, produciendo una parálisis en la abducción del globo ocular y los músculos involucrados en la expresión facial. Su presentación clínica y grados de severidad son variables, puede presentar compromiso simétrico o asimétrico. Adicionalmente, gran parte de los casos se relacionan con trastornos del lenguaje, anomalías musculoesqueléticas y orofaciales. En el presente artículo se presenta el caso de una paciente femenina de 3 años producto de un embarazo trigemelar con diagnóstico clínico de síndrome de Moebius al nacer, confirmado por neuroimagen en la que se evidencia la ausencia bilateral del nervio facial en ángulos pontocerebelosos, adicionalmente con un defecto completo en los movimientos oculares de abducción y aducción lo que impide el estrabismo convergente común en estos pacientes.

Moebius syndrome is a rare congenital disease characterized by unilateral or bilateral involvement of the VI and VII cranial nerves, which compromises the muscles that control ocular motricity with paralysis in the abduction of the eyeball and the muscles involved in the facial expression. Its clinical presentation and degrees of severity are variable, and it can be symmetric or asymmetric. Additionally, most of the cases are related to language disorders, musculoskeletal and orofacial anomalies. This paper presents the case of a 3-year-old female patient, product of a trigemellar pregnancy with a clinical diagnosis of Moebius syndrome at birth, confirmed by neuroimaging, which shows the bilateral absence of the facial nerve in point-lateral angles. Additionally she has a complete defect in abduction and adduction eye movements, which prevents the common convergent strabismus in these patients.

A síndrome de Moebius é uma doença congênita rara caracterizada pelo envolvimento unilateral ou bilateral dos nervos cranianos VI e VII, que compromete os músculos que controlam a oculomotricidade com paralisia na abdução do globo ocular e dos músculos envolvidos na expressão facial. Sua apresentação clínica e graus de gravidade são variáveis, podendo ser um comprometimento simétrico ou assimétrico. Além disso, a maioria dos casos está relacionada a distúrbios de linguagem, anomalias musculoesqueléticas e orofaciais. Este paper apresenta o caso de uma paciente de 3 anos de idade, fruto de uma gravidez trigêmea com diagnóstico clínico de Síndrome de Moebius ao nascimento, confirmado por neuroimagem em que é evidente a ausência bilateral do nervo facial nos ângulos ponto-cerebelares. Além disso, ela tem um defeito completo nos movimentos oculares de abdução e adução, o que impede o estrabismo convergente comum nesses pacientes.

Multiple schwannomas of the facial nerve mimicking cervical lymphoma: a case report.

BACKGROUND: In this report, we describe the first case in literature of a patient with multiple schwannomas of the marginal mandibular branch of the facial nerve. CASE PRESENTATION: A Caucasian patient presented with a sudden onset of left lower facial nerve palsy House-Brackmann score III for 1 month. Computed tomography imaging was performed to exclude a cerebral event and revealed multiple tumors within the left parotid gland. Duplex ultrasound and magnetic resonance imaging scans delineated multiple, hypoechoic tumors, round in shape and well defined without a hilar structure along the left mandible. For histological verification, a left-side partial parotidectomy and extirpation of an intraparotideal node was performed with use of a nerve-integrity monitor. Histomorphological analysis of the resected tissue revealed a benign schwannoma. Facial nerve function remained unchanged since the operation. The size of the nonresected tumors is currently monitored regularly by ultrasonography. Fibromatosis has been excluded. CONCLUSIONS: If multiple tumors occur in the parotid gland and the angle of the jaw, schwannomas need to be considered as a differential diagnosis. To plan the right diagnostic surgical intervention and prevent nerve damage, a thorough ultrasound examination is essential in preoperative diagnostic work-up for any suspicious lesion of the parotid gland and jaw region.

Image Fusion in Neurovascular Compression Syndrome Related to Hemifacial Spasm.

Neurovascular compression syndromes have well characterized clinical symptoms, but precise identification of the pathologic contact between the nerves and vessels can be challenging at neuroimaging. Considering that neurovascular contacts are frequent imaging findings in asymptomatic patients, correct visualization of pathological contact is crucial for the diagnosis and surgical planning. We have used magnetic resonance imaging fusion by overlaying color-coded T1-weighted postcontrast onto high-resolution T2-weighted images to better delineate imaging findings by enhancing vascular structures.

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.

Eight-and-a-half syndrome: video evidence and updated literature review.

The eight-and-a-half syndrome (EHS)-defined by the combination of a seventh cranial nerve palsy and an ipsilateral one-and-a-half syndrome-is a rare brainstem syndrome, which localises to the caudal tegmental region of the pons. We present a case of the EHS secondary to an inflammatory lesion on a previously healthy 26-year-old woman, with a literature review emphasising the relevance of aetiological assessment.

Imaging the facial nerve: A contemporary review of anatomy and pathology.

PURPOSE: The facial nerve is the seventh paired cranial nerve which anatomically can be divided into six distinct segments. There are a wide range of pathologies that may occur along each segment of the nerve. The aim of this pictorial review is to untangle the complex appearances of the facial nerve, both in its normal anatomical course and when affected by pathology. METHOD: This review takes an evidence-based segmental approach to the evaluation of the facial nerve in terms of its anatomy and clinical features of common pathologies affecting specific segments of the nerve. The typical multimodal radiological findings of common facial nerve pathologies are included in the review using imaging from select pathologically confirmed cases. RESULTS: A wide range of pathologies ranging from congenital abnormalities to inflammatory, infective and neoplastic processes can affect the facial nerve. As select segments of the nerve are better evaluated on certain imaging modalities a clear understanding of the anatomy and clinical features associated with specific facial nerve pathologies enables the radiologist to tailor the imaging test to best answer the clinical question. CONCLUSIONS: This review provides a segmental clinical-radiological approach to imaging the facial nerve. In addition, recent developments in facial nerve imaging that may come into mainstream use in the near future are touched upon.

Hemifacial Spasm Due to Bony Stenosis of the Internal Auditory Meatus: Look Beyond the Loop.

BACKGROUND: Hemifacial spasm (HFS) is a neuromuscular disorder resulting from cranial nerve VII compression at the root entry zone, characterized by brief, involuntary, progressive spasms of muscles on one side of face. The cisternal part of cranial nerve VII myelinated by Schwann cells is considered relatively resistant to compression. Rarely, direct compression over this segment without coexistent root entry zone compression may also result in HFS. An aberrant vessel posterior inferior cerebellar artery/anterior inferior cerebellar artery loop remains the leading cause of compression at this location. Cerebellopontine angle tumors or cysts may affect cranial nerve VII distally. However, bony meatal stenosis with pure distal facial nerve compression leading to HFS in the absence of other clinical symptoms has not been reported. CASE DESCRIPTION: A 53-year-old woman presented with worsening left HFS for 9 years despite multiple trials of medical therapy, which severely impeded her social life and occupation. Temporal bone computed tomography revealed severe stenosis of the left internal auditory meatus (2.36 mm) compared with the right side (4.67 mm). Under three-dimensional exoscope guidance, a left retrosigmoid suboccipital craniotomy was performed, the posterior bony wall of the internal auditory canal was drilled to decompress the canal, and durotomy was performed to release the contents. Her symptoms resolved without developing facial weakness or hearing deficits. CONCLUSIONS: An aberrant anterior inferior cerebellar artery vascular loop is usually the most frequent lesion causing compression of the distal cisternal part of the facial nerve. However, other purely distal or coexistent lesions must be actively sought for both in preoperative radiologic images and during surgery.

Surgical Outcomes of Revision Microvascular Decompression for Persistent or Recurrent Hemifacial Spasm After Surgery: Analysis of Radiologic and Intraoperative Findings.

OBJECTIVES: Microvascular decompression (MVD) is the treatment of choice for hemifacial spasm (HFS), due to the high rate of complete resolution associated with MVD. However, some patients experience recurrent or persistent symptoms after surgery. In this study, we evaluated the causes of recurrence or failure based on our surgical experience with revision of MVD for HFS and analyzed the relationship between surgical outcomes and radiologic and intraoperative findings. METHODS: Among more than 2500 patients who underwent MVD surgery for HFS, 23 patients received a second MVD in our hospital from January 2002 to December 2017. Three-dimensional time-of-flight magnetic resonance angiography and reconstructed imaging were used to identify the culprit vessel and its conflict on the root exit zone (REZ) of the facial nerve. We reviewed patients' medical records and operation videos to identify the missing points of first surgery. RESULTS: In our experience with revision of MVD, 8 patients had incomplete decompression, such as single-vessel decompression of multiple offending vessels. Teflon was not detected at the REZ but was found in other locations in 12 patients. Three patients had severe adhesion with previous Teflon around the REZ. Nineteen patients had excellent surgical outcomes at immediate postoperative evaluation; 20 patients showed spasm disappearance at 1 year after surgery and 3 patients showed persistent symptoms. Neurovascular contacts around the REZ of the facial nerve were revealed on magnetic resonance imaging of incomplete decompression and Teflon malposition patient groups. There were no clear neurovascular contacts in the patients with severe Teflon adhesion. CONCLUSIONS: The decision regarding secondary MVD for persistent or recurrent spasm is troubling. However, if neurovascular contact was observed in the MRI of the patient and there were offending vessels, the surgical outcome might be favorable.

Prevalence of Spontaneous Asymptomatic Facial Nerve Canal Meningoceles: A Retrospective Review.

BACKGROUND AND PURPOSE: The prevalence of patent facial nerve canals and meningoceles along the facial nerve course is unknown. This study aimed to assess the frequency of such findings in asymptomatic patients. MATERIALS AND METHODS: A retrospective review was completed of patients with high-resolution MR imaging of the temporal bone whose clinical presentations were unrelated to facial nerve pathology. Facial nerve canals were assessed for the presence of fluid along each segment and meningoceles within either the labyrinthine segment (fluid-filled distention, ≥1.0-mm diameter) or geniculate ganglion fossa (fluid-filled distention, ≥2.0-mm diameter). If a meningocele was noted, images were assessed for signs of CSF leak. RESULTS: Of 204 patients, 36 (17.6%) had fluid in the labyrinthine segment of the facial nerve canal and 40 (19.6%) had fluid in the geniculate ganglion fossa. Five (2.5%) had meningoceles of the geniculate ganglion fossa; no meningoceles of the labyrinthine segment of the canal were observed. No significant difference was observed in the ages of patients with fluid in the labyrinthine segment of the canal or geniculate ganglion compared with those without fluid (P = .177 and P = .896, respectively). Of the patients with a meningocele, one had a partially empty sella and none had imaging evidence of CSF leak or intracranial hypotension. CONCLUSIONS: Fluid within the labyrinthine and geniculate segments of the facial nerve canal is relatively common. Geniculate ganglion meningoceles are also observed, though less frequently. Such findings should be considered of little clinical importance without radiologic evidence of CSF otorrhea, meningitis, or facial nerve palsy.

Cochlear Erosion due to a Facial Nerve Schwannoma.

Facial nerve schwannomas are rare benign neoplasms. We report a case of a 60-year-old woman who initially presented with vestibular complaints. Magnetic resonance imaging (MRI) revealed a facial nerve schwannoma centered on the right geniculate ganglion extending in the labyrinthine segment. The patient consulted again after 2 months because she developed a sudden and severe right-sided sensorineural hearing loss. MRI showed no progression or pathological enhancement in the membranous labyrinth. A cone beam computed tomography (CT) of the temporal bone was performed and revealed a large erosion at the region of the geniculate ganglion in open communication with the middle turn of the cochlea. This case report demonstrates the importance of CT in facial nerve schwannomas for evaluating the impact on the surrounding structures.

Association between facial nerve second genu angle and facial canal dehiscence in patients with cholesteatoma: evaluation with temporal multidetector computed tomography and surgical findings / Associação entre o ângulo do segundo joelho do nervo facial e deiscência do canal facial em pacientes com colesteatoma: avaliac¸ão do osso temporal por tomografia com multidetectores e pelos achados cirúrgicos

Abstract Introduction: Otitis media, mastoiditis or the pressure effect of tumorous lesions such as cholesteatoma can be the cause of facial canal dehiscence and facial nerve paralysis. The most common segment involved in dehiscence is the tympanic segment and the second most common is the lateral aspect of the facial canal in the oval window area. Objective: To determine the prevalence of the facial canal dehiscence and the relationship between the angle at the second genu of the facial nerve and facial canal dehiscence. Methods: We evaluated the surgical findings in 113 patients who underwent surgery for cholesteatoma. Facial canal dehiscence was detected in 62 of the 113 patients. Patients were divided into two groups: Group 1, with dehiscence of the facial canal and Group 2, without dehiscence of the facial canal. Results: The mean angles at the second genu of the facial nerve in Groups 1 and 2 were 117.8º ± 9.63º and 114º ± 9.9º, respectively. There was a statistically significant difference between the mean angles at the second genu for the two groups (p = 0.04). Conclusion: In patients with dehiscence of the facial canal, the angle at the second genu was found to be wider than those without dehiscence.

Resumo Introdução: Otite média, mastoidite ou a compressão por lesões tumorais como o colesteatoma podem ser a causa da deiscência do canal facial e paralisia do nervo facial. A deiscência ocorre mais frequentemente no segmento timpânico, seguido do aspecto lateral do canal facial na área da janela oval. Objetivo: Determinar a prevalência da deiscência do canal facial e sua relação com o ângulo no segundo joelho do nervo facial. Método: Avaliamos os achados cirúrgicos para detecção de deiscência do canal facial em 113 pacientes submetidos à cirurgia de colesteatoma. A deiscência do canal facial foi observada em 62. Os pacientes foram divididos em dois grupos: Grupo 1, com deiscência do canal facial, e Grupo 2, sem deiscência do canal facial. Resultados: Os ângulos médios no segundo joelho do nervo facial nos grupos 1 e 2 foram 117,8º ± 9,63º e 114º ± 9,9º, respectivamente. Houve diferença estatisticamente significante entre os ângulos médios no segundo joelho para os dois grupos (p = 0,04). Conclusão: Em pacientes com deiscência no canal facial, foi observado que o ângulo do segundo joelho era maior do que naqueles sem deiscência.

Evaluating Perineural Spread to the Intratemporal Facial Nerve on Magnetic Resonance Imaging.

OBJECTIVES: To determine the sensitivity and specificity of magnetic resonance imaging (MRI) for the detection of perineural spread (PNS) along the intratemporal facial nerve (ITFN) in patients with head and neck cancers. STUDY DESIGN: Case series with chart review. SETTING: Tertiary care center. SUBJECTS AND METHODS: We included 58 patients with head and neck malignancies who underwent sacrifice of the ITFN between August 1, 2002, and November 30, 2015. Demographics, preoperative facial nerve function, prior oncologic treatment, and timing between MRI and surgery were recorded. Histopathology slides and preoperative MRI were reviewed retrospectively by a neuropathologist and a neuroradiologist, respectively, both blinded to clinical data. The mastoid segment of the facial nerve (referred to as the descending facial nerve [DFN]) and stylomastoid foramen (SMF) were evaluated separately. A grading system was devised when radiographically assessing PNS along the DFN. RESULTS: Histopathologic evidence of PNS was found in 21 patients (36.2%). The sensitivity and specificity of MRI in detecting PNS to the DFN were 72.7% and 87.8%, respectively. MRI showed higher sensitivity but slightly lower specificity when evaluating the SMF (80% and 82.8%, respectively). Prior oncologic treatment did not affect the false-positive rate ( P = .7084). Sensitivity was 100% when MRI was performed within 2 weeks of surgery and was 62.5% to 73.3% when the interval was greater than 2 weeks. This finding was not statistically significant (SMF, P = .7076; DFN, P = .4143). CONCLUSION: MRI shows fair to good sensitivity and good specificity when evaluating PNS to the ITFN.

Association between facial nerve second genu angle and facial canal dehiscence in patients with cholesteatoma: evaluation with temporal multidetector computed tomography and surgical findings.

INTRODUCTION: Otitis media, mastoiditis or the pressure effect of tumorous lesions such as cholesteatoma can be the cause of facial canal dehiscence and facial nerve paralysis. The most common segment involved in dehiscence is the tympanic segment and the second most common is the lateral aspect of the facial canal in the oval window area. OBJECTIVE: To determine the prevalence of the facial canal dehiscence and the relationship between the angle at the second genu of the facial nerve and facial canal dehiscence. METHODS: We evaluated the surgical findings in 113 patients who underwent surgery for cholesteatoma. Facial canal dehiscence was detected in 62 of the 113 patients. Patients were divided into two groups: Group 1, with dehiscence of the facial canal and Group 2, without dehiscence of the facial canal. RESULTS: The mean angles at the second genu of the facial nerve in Groups 1 and 2 were 117.8°±9.63° and 114°±9.9°, respectively. There was a statistically significant difference between the mean angles at the second genu for the two groups (p=0.04). CONCLUSION: In patients with dehiscence of the facial canal, the angle at the second genu was found to be wider than those without dehiscence.

Decreased Distance between Representation Sites of Distinct Facial Movements in Facial Synkinesis-A Task fMRI Study.

This study aimed to investigate the cortical functional alterations in patients with unilateral facial synkinesis using the task-designed functional magnetic resonance imaging. Fourteen unilateral synkinesis followed by peripheral facial nerve palsy patients and eighteen healthy adults were recruited in this study. Four facial motor tasks, i.e. left/right blinking and left/right smiling, were performed by each subject during the scans. Based on the activation maps, the spatial distance between the representation sites in the contralateral pre-/post-central gyrus of left or right blinking and smiling tasks (i.e. left/right B-S-distance) were calculated. Patients with unilateral facial synkinesis showed decreased B-S-distances during blinking and smiling tasks on the affected half face (9.68 ±â€¯3.92 mm) compared to both average distances in healthy controls (14.95 ±â€¯5.55 mm; p = 0.002) and unaffected half face tasks in patients (16.19 ±â€¯7.87 mm; p = 0.011). These findings demonstrated cortical reorganization in facial synkinesis and suggested a conceivable mechanism corresponding to the simultaneous facial movement. This potentially provides a new modulation target for preventive, therapeutic and rehabilitative maneuver of this disease.

The inflammatory pseudotumor presenting periodic acid-Schiff-positive inclusions with acute unilateral facial nerve palsy.

Although most acute peripheral facial palsies can be attributed to Bell's palsy, other factors, such as infection, trauma, and neoplasm, can cause facial palsy as well. Among these, facial nerve tumors are rare but should be considered in the differential diagnosis of facial palsy. Palsies due to facial nerve tumors usually present with slow onset but occasionally present as acute episodes. In such cases, facial nerve decompression is the treatment of choice to allow the tumor room to grow without compressing the nerve or its blood supply. We describe a case of severe, acute facial palsy presenting with a spindle-shaped bone erosion on the mastoid portion of the facial canal. Although facial neuroma was suspected preoperatively, emergency decompression surgery revealed that an unusual inflammatory pseudotumor was responsible for the finding. Postoperative histological analysis revealed extensive destruction of the nerve fibers, with extensive infiltration of foamy macrophages containing characteristic, diastase-resistant, periodic acid-Schiff (PAS)-positive inclusions, which are hallmark of the uncommon bacterial infections. This was a case of facial palsy with an unusual etiology. The case shows the benefit of decompression surgery not only as treatment for the palsy but also as exploratory surgery in cases of facial nerve tumor.

The impact of motor impairment on the processing of sensory information.

Sensorimotor adaptation is driven by mismatch errors between desired movements and actual movement outcomes. A mismatch error can be minimized by adjusting movements or by altering the interpretation of sensory information. While the effect of mismatch errors on the motor system has received much attention, the contribution of somatosensory feedback, particularly the sensory-motor interplay in the process of adaptation, remains poorly understood. Our study analyzes the impact of peripheral deefferentation on the plasticity of the brain networks responsible for sensory-motor adaptation, focusing particularly on changes in the processing of somatosensory information. For this aim, task-based and resting-state functional MRI was performed on 24 patients in the acute state of a left-sided idiopathic peripheral facial nerve palsy. The functional connectivity of cortical and subcortical networks was analyzed and compared to a healthy control group. We found a strong involvement of the somatosensory system and the thalamus in the adaptation process following an acute peripheral deefferentation. The investigated network shows the principal pattern of a reduced connectivity between cortical areas, while the connectivity to subcortical areas (the basal ganglia and the thalamus) is increased. We suggest that the increased connectivity between the subcortical and cortical structures indicates an active sensory-motor adaptation process. We further hypothesize that the decreased functional connectivity at the cortical level reflects an unsuccessful sensorimotor adaptation process due to the inability to solve the somatosensory-motor mismatch. These results extend our understanding of the somatosensory-motor interaction in response to a mismatch signal and highlight the importance of the thalamus in this process.