RESUMO
OBJECTIVE: This study was conducted to investigate the success rate of using the facial motor evoked potential (FMEP) of orbicularis oculi and oris muscles for facial nerve function monitoring with use of a stepwise protocol, and its usefulness in predicting facial nerve outcome during cerebellopontine angle (CPA) surgeries. METHODS: FMEPs were recorded intraoperatively from 60 patients undergoing CPA surgeries. Transcranial electrocortical stimulation (TES) was performed using corkscrew electrodes positioned at hemispheric montage (C3/C4 and CZ). The contralateral abductor pollicis brevis muscle was used as the control response. Stimulation was always applied contralaterally to the affected side using 1, 3, or 5 rectangular pulses ranging from 200 to 600 V with 50 micros of pulse duration and an interstimulus interval of 2 ms. Facial potentials were recorded from needles placed in the orbicularis oculi and oris muscles. RESULTS: FMEP from the orbicularis oris and oculi muscles could be reliably monitored in 86.7% and 85% of the patients, respectively. The immediate postoperative facial function correlated significantly with the FMEP ratio in the orbicularis oculi muscle at 80% amplitude ratio (P = .037) and orbicularis oris muscle at 35% ratio (P = .000). FMEP loss was always related to postoperative facial paresis, although in different degrees. CONCLUSION: FMEPs can be obtained reliably by using TES with 3 to 5 train pulses. Stable intraoperative FMEPs can predict a good postoperative outcome of facial function. However, further refinements of this technique are necessary to minimize artifacts and to make this method more reliable.
Assuntos
Neoplasias dos Nervos Cranianos/cirurgia , Estimulação Elétrica/métodos , Traumatismos do Nervo Facial/prevenção & controle , Nervo Facial/cirurgia , Monitorização Intraoperatória/métodos , Neuroma Acústico/cirurgia , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Neoplasias dos Nervos Cranianos/patologia , Neoplasias dos Nervos Cranianos/fisiopatologia , Nervo Facial/fisiologia , Traumatismos do Nervo Facial/etiologia , Traumatismos do Nervo Facial/fisiopatologia , Feminino , Humanos , Complicações Intraoperatórias/etiologia , Complicações Intraoperatórias/fisiopatologia , Complicações Intraoperatórias/prevenção & controle , Masculino , Pessoa de Meia-Idade , Monitorização Intraoperatória/instrumentação , Neuroma Acústico/patologia , Neuroma Acústico/fisiopatologia , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/fisiopatologia , Complicações Pós-Operatórias/prevenção & controle , Adulto JovemRESUMO
We present a 47-year-old woman with a long history of anxiety and a more recent history of shock-like facial pain and episodes of laughter without any motivation. She could not explain the laughing bursts and did not have a sense of mirth preceding it. On neurological examination she presented a VI nerve palsy and trigeminal hypoesthesia (V2 and V3) on the right side. Magnetic resonance imaging exhibited a large cystic lesion on the right middle fossa causing significant compression on the brain stem. A frontoorbitozygomatic and pretemporal combined approach was performed. During intra and extradural exploration a large tumor was found on the trigeminal nerve. The whole lesion was resected, revealing to be a neurinoma on pathological exhamination. She maintained a VI nerve palsy but had complete remission of the unmotivated laughing episodes during the one year follow up.
Assuntos
Neoplasias dos Nervos Cranianos/fisiopatologia , Riso , Neurilemoma/fisiopatologia , Doenças do Nervo Trigêmeo/fisiopatologia , Neoplasias dos Nervos Cranianos/complicações , Neoplasias dos Nervos Cranianos/cirurgia , Paralisia Facial/etiologia , Feminino , Humanos , Imageamento por Ressonância Magnética , Pessoa de Meia-Idade , Neurilemoma/complicações , Neurilemoma/cirurgia , Doenças do Nervo Trigêmeo/complicações , Doenças do Nervo Trigêmeo/cirurgiaRESUMO
We undertook a comprehensive study of children with neurofibromatosis type 1 (NF-1) cared for in a large multidisciplinary clinic to determine the prevalence of precocious puberty and its relationship to optic pathway tumors (OPTs). Precocious puberty was diagnosed in 7 of 219 children with NF-1 (5 boys and 2 girls) examined between Jan. 1, 1985, and April 20, 1993. All seven children had OPTs involving the optic chiasm; they represented 39% of children with NF-1 and chiasmal tumors (95% confidence interval, 17% to 64%). Eleven prepubertal children (aged 2 to 10 years) with NF-1 and OPTs, and age- and sex-matched NF-1 control subjects without OPTs, underwent luteinizing hormone-releasing hormone (LH-RH) stimulation tests. Two boys with OPTs had pubertal luteinizing hormone (LH) responses, and testosterone levels > 10 ng/dl. Basal LH levels were also elevated in these two boys when tested with a very sensitive immunochemiluminometric assay. None of the children without an OPT had either a pubertal response to LH-RH or an elevated basal LH level. We conclude that precocious puberty in children with NF-1 is found exclusively in those who have OPTs involving the optic chiasm; it is a common complication in those children. With the use of a highly sensitive LH assay, biochemical evidence of hypothalamic-pituitary-gonadal axis activation may be demonstrated, even without provocative testing.
Assuntos
Neoplasias dos Nervos Cranianos/complicações , Neurofibromatose 1/complicações , Doenças do Nervo Óptico/complicações , Puberdade Precoce/etiologia , Criança , Pré-Escolar , Neoplasias dos Nervos Cranianos/sangue , Neoplasias dos Nervos Cranianos/fisiopatologia , Estradiol/sangue , Feminino , Hormônio Foliculoestimulante/sangue , Hormônio Liberador de Gonadotropina/farmacologia , Humanos , Sistema Hipotálamo-Hipofisário/efeitos dos fármacos , Hormônio Luteinizante/sangue , Masculino , Neurofibromatose 1/sangue , Neurofibromatose 1/fisiopatologia , Doenças do Nervo Óptico/sangue , Doenças do Nervo Óptico/fisiopatologia , Sistema Hipófise-Suprarrenal/efeitos dos fármacos , Estudos Prospectivos , Puberdade Precoce/sangue , Puberdade Precoce/fisiopatologia , Estudos Retrospectivos , Testosterona/sangueRESUMO
To assess the natural history of optic pathway tumors (OPT) in children with neurofibromatosis type 1 (NF-1), from January 1985 through May 1993 we performed a prospective, longitudinal study of OPT in an unselected population of children with NF-1. Of 227 children with NF-1 seen in a specialty clinic, 176 (77%) underwent neuroimaging. Children in whom tumors were identified were followed closely by both repeated neuroimaging and ophthalmologic examinations to detect tumor growth or visual deterioration. Thirty-three children (19%) were found to have OPT at a median age of 4.2 years. The median age of children who had ophthalmologic complaints was significantly lower than that of children who had no such complaints (1.9 vs 5.3 years; p < 0.001). Although eight tumors were discovered because of ophthalmologic complaints or evidence of precocious puberty, 25 children (76%) were free of symptoms at the time of diagnosis. Twenty-one children (64%) had normal ophthalmologic findings at diagnosis; six children, all with chiasmal tumors, had previously unrecognized decreased visual acuity. Only three children (9%) had evidence of either tumor growth or deteriorating vision after diagnosis; the median duration of neuroimaging follow-up was 2.4 years (range, 0.2 to 7.2 years) and of ophthalmologic examinations 3.4 years (range, 0.2 to 8.1 years). All symptomatic OPT were diagnosed before 6 years of age. We conclude that OPT rarely progress during the next few years in children with NF-1 once the OPT have been discovered. The utility of screening neuroimaging for OPT in symptom-free children with NF-1 appears very limited.
Assuntos
Neoplasias dos Nervos Cranianos/fisiopatologia , Glioma/fisiopatologia , Neurofibromatose 1/fisiopatologia , Doenças do Nervo Óptico/fisiopatologia , Adolescente , Adulto , Fatores Etários , Criança , Pré-Escolar , Neoplasias dos Nervos Cranianos/complicações , Feminino , Glioma/complicações , Humanos , Lactente , Estudos Longitudinais , Masculino , Neurofibromatose 1/complicações , Doenças do Nervo Óptico/complicaçõesRESUMO
Os autores fazem uma revisäo das principais patologias que acometem o quiasma: adenomas hipofisários, meningeomas, craniofaringeomas, gliomas e aneurismas. Säo referidos os aspectos neuro-oftalmológicos das diversas desordens com ênfase para o papel do oftalmologista no diagnóstico e seguimento adequados