RESUMO

SUMMARY: The stylomastoid foramen is located on the inferior surface of the petrous part of the temporal bone between the base of the styloid process and mastoid processes. Through the stylomastoid foramen the facial nerve completes its intracranial part. The aim of this study was to analyze the morphometric parameters, shape and position of the stylomastoid foramen on the skulls in Serbian population, and to correlate it with gender and body side. The study included 44 dry adult skulls (88 stylomastoid foramen). After we determined the gender, the skulls were photographed, and then distances of the stylomastoid foramen from various important landmarks of the skull base were measured in programme ImageJ. The shape and position of the stylomastoid foramen were also noted. The statistical significance was found in male skulls between right and left side in relation to parameter (P2) the shortest distance from the upper end of the anterior margin of the mastoid process (MP) to the center of stylomastoid foramen (CSMF), and on the left side for parameter (P6) the shortest distance between CSMF and the line passing through the tip of the MP in relation to gender. The most common shape of the stylomastoid foramen was round in 46 (52.27 %) cases, and most common position was on the line passing through the upper end of the anterior margin of both MP in 36 (40.91 %) and medially to the line connecting the tips of the MP and styloid process in 88 (100 %) cases. The results of this study will be useful for neurosurgeons during surgeries on the facial nerve trunk or anesthetics to give facial nerve block near the foramen and prevent its complications.

El foramen estilomastoideo se encuentra en la superficie inferior de la parte petrosa del hueso temporal entre la base del proceso estiloides y el proceso mastoides. A través del foramen estilomastoideo el nervio facial completa su parte intracraneal. El objetivo de este estudio fue analizar los parámetros morfométricos, la forma y la posición del foramen estilomastoideo en cráneos de población serbia y correlacionarlos con el sexo y el lado del cuerpo. El estudio incluyó 44 cráneos adultos secos (88 forámenes estilomastoideos). Después de determinar el sexo, se fotografiaron los cráneos y luego se midieron en el programa ImageJ las distancias del foramen estilomastoideo desde varios puntos importantes de la base del cráneo. También se observó la forma y posición del foramen estilomastoideo. La significación estadística se encontró en cráneos de hombres entre el lado derecho e izquierdo en relación al parámetro (P2) la distancia más corta desde el extremo superior del margen anterior del proceso mastoides (PM) hasta el centro del foramen estilomastoideo (CFM), y en el lado izquierdo para el parámetro (P6) la distancia más corta entre CFM y la línea que pasa por la punta del PM en relación al sexo. La forma más común del foramen estilomastoideo era redonda en 46 (52,27 %) casos, y la posición más común estaba en la línea que pasa por el extremo superior del margen anterior de ambos PM en 36 (40,91 %) y medialmente a la línea que conecta las puntas del PM y el proceso estiloides en 88 (100 %) casos. Los resultados de este estudio serán útiles para los neurocirujanos durante las cirugías en el tronco del nervio facial o los anestésicos para bloquear el nervio facial cerca del foramen y prevenir sus complicaciones.

Assuntos

RESUMO

Background: In this experimental protocol, we evaluated the immediate and delayed repair of the buccal branch of the facial nerve (BBFN) with heterologous fibrin biopolymer (HFB) as a coaptation medium and the use of photobiomodulation (PBM), performing functional and histomorphometric analysis of the BBFN and perioral muscles. Methods: Twenty-eight rats were divided into eight groups using the BBFN bilaterally (the left nerve was used for PBM), namely: G1 - control group, right BBFN (without injury); G2 - control group, left BBFN (without injury + PBM); G3 - Denervated right BBFN (neurotmesis); G4 - Denervated left BBFN (neurotmesis + PBM); G5 - Immediate repair of right BBFN (neurotmesis + HFB); G6 - Immediate repair of left BBFN (neurotmesis + HFB + PBM); G7 - Delayed repair of right BBFN (neurotmesis + HFB); G8 - Delayed repair of left BBFN (neurotmesis + HFB + PBM). Delayed repair occurred after two weeks of denervation. All animals were sacrificed after six weeks postoperatively. Results: In the parameters of the BBFN, we observed inferior results in the groups with delayed repair, in relation to the groups with immediate repair, with a significant difference (p < 0.05) in the diameter of the nerve fiber, the axon, and the thickness of the myelin sheath of the group with immediate repair with PBM compared to the other experimental groups. In measuring the muscle fiber area, groups G7 (826.4 ± 69.90) and G8 (836.7 ± 96.44) were similar to G5 (882.8 ± 70.51). In the functional analysis, the G7 (4.10 ± 0.07) and G8 (4.12 ± 0.08) groups presented normal parameters. Conclusion: We demonstrated that delayed repair of BBFN is possible with HFB, but with worse results compared to immediate repair, and that PBM has a positive influence on nerve regeneration results in immediate repair.

RESUMO

Introduction Facial nerve stimulation (FNS) is a complication in cochlear implant (CI) when the electrical current escapes from the cochlea to the nearby facial nerve. Different management to reduce its effects are available, although changes might result in a less-than-ideal fitting for the CI user, eventually reducing speech perception. Objective To verify the etiologies that cause FNS, to identify strategies in managing FNS, and to evaluate speech recognition in patients who present FNS. Methods Retrospective study approved by the Ethical Board of the Institution. From the files of a CI group, patients who were identified with FNS either during surgery or at any time postoperatively were selected. Data collection included: CI manufacturer, electrode array type, age at implantation, etiology of hearing loss, FNS identification date, number of electrodes that generated FNS, FNS management actions, and speech recognition in quiet and in noise. Results Data were collected from 7 children and 25 adults. Etiologies that cause FNS were cochlear malformation, head trauma, meningitis, and otosclerosis; the main actions included decrease in the stimulation levels followed by the deactivation of electrodes. Average speech recognition in quiet before FNS was 86% and 80% after in patients who were able to accomplish the test. However, there was great variability, ranging from 0% in quiet to 90% of speech recognition in noise. Conclusion Etiologies that cause FNS are related to cochlear morphology alterations. Facial nerve stimulation can be solved using speech processor programming parameters; however, it is not possible to predict outcomes, since results depend on other variables.

RESUMO

Introdução: O envelhecimento facial é um processo gradual, complexo e multifatorial. É o resultado de mudanças na qualidade, volume e posicionamento dos tecidos. Cirurgiões plásticos têm modificado sua abordagem na cirurgia do rejuvenescimento facial optando pelo plano subaponeurótico (SMAS). O objetivo deste estudo é analisar 100 casos de pacientes operados pela técnica de SMAS profundo, avaliando sua aplicabilidade e eficácia. Método: Foram avaliados 100 pacientes, submetidos a cirurgia plástica facial pela técnica de SMAS profundo - "Deep Smas", e acompanhados por 6 meses. Observou-se a satisfação dos pacientes, número de complicações, número de reoperações, riscos e vantagens da técnica. Resultados: Foram operados 100 pacientes, num período de 3 anos. A idade variou de 41 a 79 anos, sendo 95% sexo feminino. As complicações foram 8 casos (8%) de lesões de ramos do nervo facial, sendo: 4 casos lesão do zigomático, 3 casos de lesão do mandibular e 1 caso de lesão do bucal; houve 1 caso (1%) de queloide retroauricular; 1 caso (1%) de hematoma. Em relação às revisões cirúrgicas, houve 8 casos (8%) de complementação cirúrgica por insatisfação das pacientes. Houve 15% de lesões nervosas entre a 1ª e a 40ª cirurgia, 5% entre a 41ª e a 80ª, e nenhuma lesão entre o 81º e o 100º paciente. Conclusão: O lifting facial profundo ou subSMAS mostrou ser efetivo, proporcionando bons resultados estéticos. Apresenta baixa taxa de recidiva e baixa taxa de morbidade, porém, necessita de uma longa curva de aprendizagem.

Introduction: Facial aging is a gradual, complex, and multifactorial process. It is the result of changes in the quality, volume, and positioning of tissues. Plastic surgeons have modified their approach to facial rejuvenation surgery, opting for the subaponeurotic plane (SMAS). The objective of this study is to analyze 100 cases of patients operated on using the deep SMAS technique, evaluating its applicability and effectiveness. Method: 100 patients were evaluated, undergoing facial plastic surgery using the deep SMAS technique - "Deep Smas", and followed up for 6 months. Patient satisfaction, number of complications, number of reoperations, risks, and advantages of the technique were observed. Results: 100 patients were operated on over 3 years. Age ranged from 41 to 79 years, with 95% being female. The complications were 8 cases (8%) of injuries to branches of the facial nerve, of which 4 cases of zygomatic injury, 3 cases of mandibular injury, and 1 case of buccal injury; there was 1 case (1%) of post-auricular keloid; 1 case (1%) of hematoma. Regarding surgical revisions, there were 8 cases (8%) of surgical completion due to patient dissatisfaction. There were 15% of nerve injuries between the 1st and 40th surgery, 5% between the 41st and 80th, and no injuries between the 81st and 100th patient. Conclusion: Deep facial lifting or subSMAS has proven to be effective, providing good aesthetic results. It has a low recurrence rate and low morbidity rate; however, it requires a long learning curve.

RESUMO

Introdução: Os estudos de anatomia em cadáveres permitiram um melhor entendimento das estruturas da face e, consequentemente, mais segurança ao explorar os planos profundos da região facial. Uma boa técnica deve ser segura, reprodutível e respeitar os pontos anatômicos. O objetivo deste trabalho é desmistificar a técnica de deep plane facelifting por meio da dissecção de cadáveres e exposição das estruturas faciais. Método: A reprodução da técnica de "deep plane facelifting" foi realizada em 14 hemifaces de 7 peças de cadáveres frescos no Instituto de Treinamento de Cadáver em Curitiba no ano de 2021. A técnica cirúrgica foi realizada conforme nossa prática clínica e reproduzida no cadáver. Após o procedimento, as estruturas anatômicas faciais foram dissecadas para correlacionar seu posicionamento junto aos espaços anatômicos da face. Foram avaliados os posicionamentos dos ligamentos da face, vascularização e os ramos do nervo facial. Resultados: Foram identificados os espaços anatômicos relevantes à técnica de deep plane facelifting, como os espaços massetéricos inferior e superior, espaço pré-zigomático, espaço bucal e espaço cervical. Os ramos do nervo facial foram identificados no plano subSMAS e correlacionados com os espaços e planos anatômicos. Conclusão: A técnica de deep plane facelift pode ser reproduzida com segurança desde que sejam respeitados dois parâmetros. O primeiro é a entrada correta nos espaços a fim de respeitar a anatomia. O segundo é o uso de descoladores rombos para dissecção nos planos profundos da face a fim de evitar lesão nervosa dos ramos do nervo facial.

Introduction: Anatomy studies on cadavers have allowed a better understanding of the structures of the face and, consequently, greater safety when exploring the deep planes of the facial region. A good technique must be safe, reproducible, and respect anatomical points. The objective of this work is to demystify the deep plane facelifting technique through the dissection of cadavers and exposure of facial structures. Method: The reproduction of the "deep plane facelifting" technique was performed on 14 hemifaces of 7 pieces of fresh cadavers at the Instituto de Treinamento de Cadáver (Cadaver Training Institute) in Curitiba in 2021. The surgical technique was performed according to our clinical practice and reproduced on the cadaver. After the procedure, the facial anatomical structures were dissected to correlate their positioning with the anatomical spaces of the face. The positioning of the facial ligaments, vascularization, and branches of the facial nerve were evaluated. Results: The anatomical spaces relevant to the deep plane facelifting technique were identified, such as the inferior and superior masseteric spaces, prezygomatic space, buccal space, and cervical space. The facial nerve branches were identified in the sub-SMAS plane and correlated with the anatomical spaces and planes. Conclusion: The deep plane facelift technique can be reproduced safely as long as two parameters are respected. The first is the correct entry into spaces to respect the anatomy. The second is the use of blunt detachers for dissection in the deep planes of the face to avoid nerve damage to the branches of the facial nerve.

RESUMO

Moebius syndrome (MBS) is a congenital cranial dysinnervation disorder (CCDD) characterized by a bilateral palsy of abducens and facial cranial nerves, which may coexist with other cranial nerves palsies, mostly those found in the dorsal pons and medulla oblongata. MBS is considered a "rare" disease, occurring in only 1:50,000 to 1:500,000 live births, with no gender predominance. Three independent theories have been described to define its etiology: the vascular theory, which talks about a transient blood flow disruption; the genetic theory, which takes place due to mutations related to the facial motor nucleus neurodevelopment; and last, the teratogenic theory, associated with the consumption of agents such as misoprostol during the first trimester of pregnancy. Since the literature has suggested the existence of these theories independently, this review proposes establishing a theory by matching the MBS molecular bases. This review aims to associate the three etiopathogenic theories at a molecular level, thus submitting a combined postulation. MBS is most likely an underdiagnosed disease due to its low prevalence and challenging diagnosis. Researching other elements that may play a key role in the pathogenesis is essential. It is common to assume the difficulty that patients with MBS have in leading an everyday social life. Research by means of PubMed and Google Scholar databases was carried out, same in which 94 articles were collected by using keywords with the likes of "Moebius syndrome," "PLXND1 mutations," "REV3L mutations," "vascular disruption AND teratogens," and "congenital facial nerve palsy." No exclusion criteria were applied.

Assuntos

RESUMO

BACKGROUND: Facial nerve dysfunction can be a devastating trouble for post-parotidectomy patients. OBJECTIVE: To assess rehabilitation outcomes concerning patients with post-parotidectomy facial nerve dysfunction, comparing benign versus malignant neoplasms. METHODS: Prospective study enrolling adults who underwent parotidectomy with facial nerve sparing between 2016 and 2020. The Modified Sunnybrook System (mS-FGS) was used for facial assessments. Physiotherapy began on the first post-operative day with a tailored program of facial exercises based on Neuromuscular Retraining, to be performed at home 3 times/day. From the first outpatient consultation, Proprioceptive Neuromuscular Facilitation was added to the treatment of cases with moderate or severe facial dysfunctions. RESULTS: Benign and malignant groups had a statistically significant improvement in mS-FGS (p < 0.001 and p = 0.005, respectively). There was no significant difference between groups regarding treatment duration or number of physiotherapy sessions performed. The history of previous parotidectomy resulted in more severe initial dysfunctions and worse outcome. Age over 60 years and initially more severe dysfunctions impacted the outcome. CONCLUSION: Patients with benign and malignant parotid neoplasms had significant and equivalent improvement in postoperative facial dysfunction following an early tailored physiotherapy program, with no significant difference in the final facial score, treatment duration, or number of sessions required.

Assuntos

RESUMO

OBJECTIVE: To review key evidence-based recommendations for the diagnosis and treatment of peripheral facial palsy in children and adults. METHODS: Task force members were educated on knowledge synthesis methods, including electronic database search, review and selection of relevant citations, and critical appraisal of selected studies. Articles written in English or Portuguese on peripheral facial palsy were eligible for inclusion. The American College of Physicians' guideline grading system and the American Thyroid Association's guideline criteria were used for critical appraisal of evidence and recommendations for therapeutic interventions. RESULTS: The topics were divided into 2 main parts: (1) Evaluation and diagnosis of facial palsy: electrophysiologic tests, idiopathic facial palsy, Ramsay Hunt syndrome, traumatic peripheral facial palsy, recurrent peripheral facial palsy, facial nerve tumors, and peripheral facial palsy in children; and (2) Rehabilitation procedures: surgical decompression of the facial nerve, facial nerve grafting, surgical treatment of long-term peripheral facial palsy, and non-surgical rehabilitation of the facial nerve. CONCLUSIONS: Peripheral facial palsy is a condition of diverse etiology. Treatment should be individualized according to the cause of facial nerve dysfunction, but the literature presents better evidence-based recommendations for systemic corticosteroid therapy.

Assuntos

RESUMO

Abstract Introduction Facial nerve stimulation (FNS) is a complication in cochlear implant (CI) when the electrical current escapes from the cochlea to the nearby facial nerve. Different management to reduce its effects are available, although changes might result in a less-than-ideal fitting for the CI user, eventually reducing speech perception. Objective To verify the etiologies that cause FNS, to identify strategies in managing FNS, and to evaluate speech recognition in patients who present FNS. Methods Retrospective study approved by the Ethical Board of the Institution. From the files of a CI group, patients who were identified with FNS either during surgery or at any time postoperatively were selected. Data collection included: CI manufacturer, electrode array type, age at implantation, etiology of hearing loss, FNS identification date, number of electrodes that generated FNS, FNS management actions, and speech recognition in quiet and in noise. Results Data were collected from 7 children and 25 adults. Etiologies that cause FNS were cochlear malformation, head trauma, meningitis, and otosclerosis; the main actions included decrease in the stimulation levels followed by the deactivation of electrodes. Average speech recognition in quiet before FNS was 86% and 80% after in patients who were able to accomplish the test. However, there was great variability, ranging from 0% in quiet to 90% of speech recognition in noise. Conclusion Etiologies that cause FNS are related to cochlear morphology alterations. Facial nerve stimulation can be solved using speech processor programming parameters; however, it is not possible to predict outcomes, since results depend on other variables.

RESUMO

Abstract Objective To review key evidence-based recommendations for the diagnosis and treatment of peripheral facial palsy in children and adults. Methods Task force members were educated on knowledge synthesis methods, including electronic database search, review and selection of relevant citations, and critical appraisal of selected studies. Articles written in English or Portuguese on peripheral facial palsy were eligible for inclusion. The American College of Physicians' guideline grading system and the American Thyroid Association's guideline criteria were used for critical appraisal of evidence and recommendations for therapeutic interventions. Results The topics were divided into 2 main parts: (1) Evaluation and diagnosis of facial palsy: electrophysiologic tests, idiopathic facial palsy, Ramsay Hunt syndrome, traumatic peripheral facial palsy, recurrent peripheral facial palsy, facial nerve tumors, and peripheral facial palsy in children; and (2) Rehabilitation procedures: surgical decompression of the facial nerve, facial nerve grafting, surgical treatment of long-term peripheral facial palsy, and non-surgical rehabilitation of the facial nerve. Conclusions Peripheral facial palsy is a condition of diverse etiology. Treatment should be individualized according to the cause of facial nerve dysfunction, but the literature presents better evidence-based recommendations for systemic corticosteroid therapy.

RESUMO

Abstract Background: Facial nerve dysfunction is the principal postoperative complication related to parotidectomy. Objective: To test the hypothesis that the modified Sunnybrook Facial Grading System (mS-FGS) is superior to the original S-FGS in the assessment of facial nerve function following parotidectomy. Methods: Prospective, longitudinal study evaluating patients with primary or metastatic parotid neoplasms undergoing parotidectomy with facial nerve-sparing between 2016 and 2020. The subjects were assessed twice, on the first postoperative day and at the first outpatient evaluation, 20-30 days post-surgery. Facial assessments were performed using the original and modified (plus showing the lower teeth) versions of the Sunnybrook System and documented by pictures and video recordings. Intra- and inter-rater agreements regarding the assessment of the new expression were analyzed. Results: 101 patients were enrolled. In both steps, the results from the mS-FGS were significantly lower (p < 0.001). Subjects with a history of previous parotidectomy and those who underwent neck dissection had more severe facial nerve impairment. The mandibular marginal branch was the most frequently injured, affecting 68.3% of the patients on the first postoperative day and 52.5% on the first outpatient evaluation. Twenty patients (19.8%) presented an exclusive marginal mandibular branch lesion. The inter-rater agreement of the new expression assessment ranged from substantial to almost perfect. The intra-rater agreement was almost perfect (wk = 0.951). Conclusion: The adoption of the Modified Sunnybrook System, which includes evaluation of the mandibular marginal branch, increases the accuracy of post-parotidectomy facial nerve dysfunction appraisal.

Resumo Antecedentes: A disfunção do nervo facial é a principal complicação pós-operatória relacionada à parotidectomia. Objetivo: Testar a hipótese de que o sistema Sunnybrook de graduação facial modificado (mS-FGS) é superior ao S-FGS original na avaliação da função do nervo facial após parotidectomia. Métodos: Estudo longitudinal prospectivo avaliando o pós-operatório de pacientes com neoplasias parotídeas primárias ou metastáticas, submetidos à parotidectomia com preservação do nervo facial, entre 2016 e 2020. Os indivíduos foram avaliados duas vezes, no primeiro dia de pós-operatório e na primeira avaliação ambulatorial, 20-30 dias após a cirurgia. As avaliações faciais foram realizadas usando as versões original e modificada (que incluem mostrar os dentes inferiores) do sistema Sunnybrook e documentadas por fotos e vídeos. Foram adicionalmente analisadas as concordâncias intra e interexaminadoras da avaliação da nova expressão. Resultados: Cento e um pacientes foram incluídos. Em ambas as etapas, os resultados do mS-FGS foram significativamente menores (p < 0,001). Indivíduos com história de parotidectomia prévia e aqueles submetidos ao esvaziamento cervical apresentaram comprometimento mais grave do nervo facial. O ramo marginal mandibular foi o mais afetado, acometendo 68,3% dos pacientes no primeiro dia de pós-operatório e 52,5% na primeira avaliação ambulatorial. Vinte pacientes (19,8%) apresentaram lesão exclusiva do ramo marginal mandibular. A concordância interexaminadores da avaliação da nova expressão variou de substancial a quase perfeita. A concordância intraexaminador foi quase perfeita (wk = 0,951). Conclusão: A adoção do sistema Sunnybrook modificado, que inclui a análise do ramo marginal mandibular, aumenta a precisão da avaliação da disfunção do nervo facial pós-parotidectomia.

RESUMO

OBJECTIVE: The objective was to evaluate whether the position of the nerves within the internal auditory canal (IAC) has any effect on preoperative and postoperative cochlear and facial nerve function in patients with intracanalicular vestibular schwannoma (VS) resected through the retrosigmoid transmeatal approach. METHODS: Forty-four patients with sporadic intracanalicular VS, from a series of 710 patients with VS who underwent operations from January 1993 to April 2022, were retrospectively reviewed. The pattern of displacement of the cranial nerves and tumor within the IAC was recorded. Tumors were divided into 2 types: type T1A lesions had only anteriorly displaced nerves, and type T1B had posteriorly displaced vestibular nerves and anteriorly displaced facial and cochlear nerves. Differences in surgical outcomes between groups in terms of facial nerve function and hearing preservation were evaluated. RESULTS: Thirty-five cases (79.5%) were T1A tumors and 9 were T1B (20.5%). Gross-total resection and anatomical preservation of the facial and cochlear nerves were achieved in all patients. Postoperatively, all patients with T1A VS maintained normal facial nerve function; however, among T1B VS patients, 6 (67%) retained House-Brackmann grade I, 2 worsened to grade II, and 1 worsened to grade III at 6 months (p = 0.006). The 27 T1A VS patients with serviceable hearing maintained this status, and an additional patient with nonserviceable hearing improved to serviceable hearing; among T1B VS patients, only 2 of the 5 patients with serviceable hearing remained as such, 2 evolved to nonserviceable hearing, and 1 lost hearing after surgery (p = 0.0022). T1B VS patients had a 24-fold risk of facial nerve deterioration (relative risk [RR] 25.2, 95% CI 1.42-448.57, p = 0.028) and a 32-fold risk of hearing deterioration (RR 32.7, 95% CI 1.93-553, p = 0.016) after surgery. CONCLUSIONS: In intracanalicular VS, postoperative cochlear and facial nerve function are directly related to the location of the tumor in relation to the nerves, with worse outcomes in cases where the tumor is located between the vestibular and facial-cochlear nerves.

Assuntos

RESUMO

Abstract Introduction The surgical management that achieves minimal morbidity and mortality for patients with glomus and non-glomus tumors involving the jugular foramen (JF) region requires a comprehensive understanding of the complex anatomy, anatomic variability, and pathological anatomy of this region. Objective The aim of this study is to propose a rational guideline to expose and preserve the lower cranial nerves (CNs) in the lateral approach of the JF. Methods The technique utilized is the gross and microdissection of 4 fixed cadaveric heads to revise the JF's surgical anatomy and high part of the carotid sheath compared with surgical cases to understand and preserve the integrity of lower CNs. The method involves radical mastoidectomy, microdissection of the JF, facial nerve, and high neck just below the carotid canal and the JF. The CNs IX, X, XI, and XII are microscopically dissected and kept in sight up to the JF. Results This study realized well the surgical and applied anatomy of the lower CNs with relation to the facial nerve and JF. Conclusions The JF anatomy is complicated, and the key to safely operate on it and preserving the lower CNs is to find the posterior belly of the digastric muscle, to skeletonize the facial nerve, to remove the mastoid tip preserving the stylomastoid foramen, to skeletonize the sigmoid sinus and posterior fossa dura not only anterior but also posteroinferior to reach and drill the jugular tubercle.

RESUMO

Introduction The surgical management that achieves minimal morbidity and mortality for patients with glomus and non-glomus tumors involving the jugular foramen (JF) region requires a comprehensive understanding of the complex anatomy, anatomic variability, and pathological anatomy of this region. Objective The aim of this study is to propose a rational guideline to expose and preserve the lower cranial nerves (CNs) in the lateral approach of the JF. Methods The technique utilized is the gross and microdissection of 4 fixed cadaveric heads to revise the JF's surgical anatomy and high part of the carotid sheath compared with surgical cases to understand and preserve the integrity of lower CNs. The method involves radical mastoidectomy, microdissection of the JF, facial nerve, and high neck just below the carotid canal and the JF. The CNs IX, X, XI, and XII are microscopically dissected and kept in sight up to the JF. Results This study realized well the surgical and applied anatomy of the lower CNs with relation to the facial nerve and JF. Conclusions The JF anatomy is complicated, and the key to safely operate on it and preserving the lower CNs is to find the posterior belly of the digastric muscle, to skeletonize the facial nerve, to remove the mastoid tip preserving the stylomastoid foramen, to skeletonize the sigmoid sinus and posterior fossa dura not only anterior but also posteroinferior to reach and drill the jugular tubercle.

RESUMO

SUMMARY: To clarify the path of the temporal branch of facial nerve (TB) crossing the zygomatic arch (ZA). Eighteen fresh adult heads specimens were carefully dissected in the zygomatic region, with the location of TB as well as its number documented. The hierarchical relationship between the temporal branch and the soft tissue in this region was observed on 64 P45 plastinated slices. 1. TB crosses the ZA as type I (21.8 %), type II (50.0 %,), and type III (28.1 %) twigs. 2. At the level of the superior edge of the ZA, the average distance between the anterior trunk of TB and the anterior part of the auricle is 36.36±6.56 mm, for the posterior trunk is 25.59±5.29 mm. At the level of the inferior edge of the ZA, the average distance between the anterior trunk of TB and the anterior part of the auricle is 25.77±6.19 mm, for the posterior trunk is 19.16±4.71 mm. 3. The average length of ZA is 62.06±5.36 mm. TB crosses the inferior edge of the ZA at an average of 14.67±6.45 mm. TB crosses the superior edge of the ZA at an average of 9.08±4.54 mm. 4. At the level of the ZA, TB passes on the surface of the pericranium while below the SMAS. The TB obliquely crosses the middle 1/3 part of the superior margin of the ZA and the junction of the middle 1/3 part and the posterior 1/3 part of the inferior margin of the ZA below the SMAS while beyond the periosteum. It is suggested that this area should be avoided in clinical operation to avoid the injury of TB.

El objetivo de estudio fue esclarecer el trayecto del ramo temporal del nervio facial (RT) que cruza el arco cigomático (AC). Se disecaron la región cigomática de 18 especímenes de cabezas sin fijar de individuos adultas y se documentó la ubicación del RT y su número de ramos. La relación jerárquica entre el ramo temporal y el tejido blando en esta región se observó en 64 cortes plastinados o P45. 1º El RT cruza el AC como tipo I (21,8 %), tipo II (50,0 %) y tipo III (28,1 %). 2º A nivel del margen superior del AC, la distancia promedio entre el tronco anterior de RT y la parte anterior de la aurícula fue de 36,36±6,56 mm, para el tronco posterior fue de 25,59±5,29 mm. A nivel del margen inferior del AC, la distancia promedio entre el tronco anterior del RT y la parte anterior de la aurícula era de 25,77±6,19 mm, para el tronco posterior era de 19,16±4,71 mm. 3º La longitud media de RT fue de 62,06±5,36 mm. EL RT cruzaba el margen inferior del AC a una distancia media de 14,67±6,45 mm. El RT cruzaba el margen superior del AC a una distancia media de 9,08±4,54 mm. 4º Anivel del AC, el RT pasaba por la superficie del pericráneo mientras se encuentra por debajo del SMAS. El RT cruza oblicuamente el tercio medio del margen superior del AC y la unión del tercio medio y el tercio posterior del margen inferior del AC por debajo del SMAS, más allá del periostio. Se sugiere que esta área debe evitarse en la operación clínica para evitar la lesión de la RT.

Assuntos

RESUMO

La parálisis o paresia facial alternobárica es una neuropraxia del séptimo nervio cra-neal debido a cambios de presión. Se produce en el contexto de una disfunción de la trompa de Eustaquio, una dehiscencia canal del nervio facial y cambios en la presión atmosférica. Se considera una rara complicación de barotrauma. Su prevalencia es difícil de estimar y, probablemente, se encuentre subreportada. La forma de presentación más habitual incluye paresia facial, plenitud aural, hipoacusia, otalgia, parestesias faciales y linguales. La mayoría de los episodios son transitorios, con una duración entre minutos y algunas horas, con recuperación posterior completa. Entre los diagnósticos diferenciales se encuentran causas periféricas y centrales de paresia facial, las cuales hay que sospechar ante la persistencia de los síntomas en el tiempo o ante la presencia de otros signos o síntomas neurológicos. La evaluación inicial debe incluir un examen otoneurológico completo. La tomografía computarizada de hueso temporal favorece la visualización de posibles dehiscencias del canal del facial. La prevención de nuevos episodios incluye la práctica de ecualización efectiva, la resolución de la disfunción de la trompa de Eustaquio y en algunos casos específicos, métodos alternativos de ventilación del oído medio como la colocación de tubos de ventilación. Una vez instalada la parálisis facial, si no se produce recuperación espontánea, el uso de corticoides es una opción. Se presenta un caso de paresia facial alternobárica recurrente y una revisión de literatura.

Alternobaric facial palsy or paralysis is a neuropraxia of the seventh cranial nerve due to pressure changes. It occurs in the context of Eustachian tube dysfunction, facial nerve canal dehiscence, and changes in atmospheric pressure. It is considered a rare complication of barotrauma. Its prevalence is difficult to estimated, and this condition is probably underreported. The most common form of presentation includes facial weakness, ear fullness or pressure, hearing loss, otalgia, facial and lingual paresthesias. Most episodes are transient, lasting from minutes to a few hours, with a subsequent complete recovery. Among the possible differential diagnoses are peripheral and central causes of facial paralysis, which must be suspected due to the persistence of symptoms over time or the presence of other neurological signs or symptoms. The initial evaluation should include a complete otoneurological examination. Computed tomography of the temporal bone is useful for the visualization of facial canal dehiscence. Prevention of further episodes includes practicing effective equalization, Eustachian tube dysfunction treatment, and in certain specific cases, alternative middle ear ventilation methods such as tympanostomy tubes. Once facial paralysis is established, if spontaneous recovery does not occur, the use of corticosteroids is considered an option. A case of recurrent alternobaric facial paresis and a review of the literature are presented.

Assuntos

RESUMO

Peripheral nerve injuries impair the patient's functional capacity, including those occurring in the facial nerve, which require effective medical treatment. Thus, we investigated the use of heterologous fibrin biopolymer (HFB) in the repair of the buccal branch of the facial nerve (BBFN) associated with photobiomodulation (PBM), using a low-level laser (LLLT), analyzing the effects on axons, muscles facials, and functional recovery. This experimental study used twenty-one rats randomly divided into three groups of seven animals, using the BBFN bilaterally (the left nerve was used for LLLT): Control group-normal and laser (CGn and CGl); Denervated group-normal and laser (DGn and DGl); Experimental Repair Group-normal and laser (ERGn and ERGl). The photobiomodulation protocol began in the immediate postoperative period and continued for 5 weeks with a weekly application. After 6 weeks of the experiment, the BBFN and the perioral muscles were collected. A significant difference (p < 0.05) was observed in nerve fiber diameter (7.10 ± 0.25 µm and 8.00 ± 0.36 µm, respectively) and axon diameter (3.31 ± 0.19 µm and 4.07 ± 0.27 µm, respectively) between ERGn and ERGl. In the area of muscle fibers, ERGl was similar to GC. In the functional analysis, the ERGn and the ERGI (4.38 ± 0.10) and the ERGI (4.56 ± 0.11) showed parameters of normality. We show that HFB and PBM had positive effects on the morphological and functional stimulation of the buccal branch of the facial nerve, being an alternative and favorable for the regeneration of severe injuries.

RESUMO

Schwann cells (SCs) are essential for the regenerative processes of peripheral nerve injuries. However, their use in cell therapy is limited. In this context, several studies have demonstrated the ability of mesenchymal stem cells (MSCs) to transdifferentiate into Schwann-like cells (SLCs) using chemical protocols or co-culture with SCs. Here, we describe for the first time the in vitro transdifferentiation potential of MSCs derived from equine adipose tissue (AT) and equine bone marrow (BM) into SLCs using a practical method. In this study, the facial nerve of a horse was collected, cut into fragments, and incubated in cell culture medium for 48 h. This medium was used to transdifferentiate the MSCs into SLCs. Equine AT-MSCs and BM-MSCs were incubated with the induction medium for 5 days. After this period, the morphology, cell viability, metabolic activity, gene expression of glial markers glial fibrillary acidic protein (GFAP), myelin basic protein (MBP), p75 and S100ß, nerve growth factor (NGF), brain-derived neurotrophic factor (BDNF), and glial cell-derived neurotrophic factor (GDNF), and the protein expression of S100 and GFAP were evaluated in undifferentiated and differentiated cells. The MSCs from the two sources incubated with the induction medium exhibited similar morphology to the SCs and maintained cell viability and metabolic activity. There was a significant increase in the gene expression of BDNF, GDNF, GFAP, MBP, p75, and S100ß in equine AT-MSCs and GDNF, GFAP, MBP, p75, and S100ß in equine BM-MSCs post-differentiation. Immunofluorescence analysis revealed GFAP expression in undifferentiated and differentiated cells, with a significant increase in the integrated pixel density in differentiated cells and S100 was only expressed in differentiated cells from both sources. These findings indicate that equine AT-MSCs and BM-MSCs have great transdifferentiation potential into SLCs using this method, and they represent a promising strategy for cell-based therapy for peripheral nerve regeneration in horses.

Assuntos

RESUMO

Abstract Objectives: The aim of this study was to assess the relationship between the stimulation amplitude and the distance to the facial nerve. Methods: This study was designed as a prospective clinical study. A total of 20 patients (12 males, 8 females) were included. Partial superficial parotidectomy was performed in all patients with intraoperative facial monitoring. Measurements were made on the main trunk and major branches. Stimulation was started at 1 mA and incrementally increased to 2 and 3mA's. The shortest distance creating a robust response (>100mV) was recorded. Results: At 1 mA, 2 mA and 3 mA stimulation intensity, the average distance between the tip of the stimulation probe and the main trunk was 2.20±0.76 mm (range 1-3 mm), 3.80±0.95 mm (range 2-5 mm), 4.80±1.05 mm (range 3-7 mm) respectively. The stimulus intensity was inversely proportional in respect to the distance between the nerve and the tip of the stimulus probe (P < .00). The same relation was present in the facial nerve major branch measurements (P < .00). Conclusion: The proportional stimulation amplitude and distance to the facial nerve is thought to be a reliable auxillary method to assist the surgeon by facilitating the estimation of the distance to the facial nerve during extracapsular dissection and minimally invasive cases where the facial nerve isn't routinely dissected. Level of evidence: Level 3.

RESUMO

Abstract Objective: To analyze the morphofunctional regeneration process of facial nerve injury in the presence of insulin-like growth factor-1 and mesenchymal stem cells. Methods: Fourteen Wistar rats suffered unilateral facial nerve crushing and were randomly divided into two groups. All received insulin-like growth factor-1 inoculation, but only half of the animals received an additional inoculation of mesenchymal stem cells. The animals were followed for 90 days and facial nerve regeneration was analyzed via spontaneous facial motor function tests and immunohistochemistry in the nerve motor nucleus. Results: The group that received the growth factor and stem cells showed a statistically superior mean in vibrissae movements (p<0.01), touch reflex (p = 0.05) and eye closure (p<0.01), in addition to better immunohistochemistry reactivity. There was a statistically significant difference in the mean number of cells in the facial nerve nucleus between the experimental groups (p = 0.025), with the group that received the growth factor and stem cells showing the highest mean. Conclusion: The association between growth factor and stem cells potentiates the morphofunctional regeneration of the facial nerve, occurring faster and more effectively. Level of Evidence: 4, degree of recommendation C.