RESUMEN
Cisternal spinal accessory schwannoma are still a rare condition without neurofibromatosis with only 32 cases reported so far. We describe a cisternal accessory schwannoma presented in a 36-year-old woman with posterior cervical pain and cervical mieolopaty, defined by grade IV tetraparesia. A suboccipital craniectomy with C1 posterior arch resection was performed. During microsurgical dissection together with electrophysiological monitoring and nerve stimulation tumor was identified as having the spinal accessory root as its origins. Carefully intraneural dissection was then performed with complete lesion removal, histopatological examination confirmed the hypothesis of schwannoma. The patient was free from pain and improved her neurological status with no accessory nerve palsy. Complete surgical resection is indicated for such lesions and can be achieved with good outcome.
O schwannoma do ramo espinhal do nervo acessório em sua porção cisternal, quando não associado à neurofibromatose, é uma condição rara, com apenas 32 relatos de caso na literatura. O diagnóstico diferencial da lesão deve ser atentado, principalmente no que diz respeito à preservação da função motora do nervo acessório. Este é um relato de caso de uma paciente do sexo feminino de 36 anos com queixa de cervicalgia associada à mielopatia cervical compressiva secundária à lesão expansiva intradural, extramedular, estendendo-se do forame magno até a porção superior da lâmina de C2. A paciente foi submetida a uma craniectomia de fossa posterior e ressecção do arco posterior de C1. Durante exploração cirúrgica, auxiliada por monitoração eletrofisiológica e estimulação neural, foi identificado que a lesão tinha origem no ramo espinhal do nervo acessório direito. Foi então ressecada de forma completa com preservação dos fascículos íntegros do nervo de origem. O exame anatomopatológico confirmou a hipótese de schwannoma. A paciente evoluiu sem dor e com melhora do quadro neurológico, sendo preservada a função do nervo acessório. O schwannoma do ramo espinhal do nervo acessório é uma condição rara. A ressecção cirúrgica total é o tratamento de escolha para esses pacientes e pode ser alcançada sem lesões neurológicas significativas secundárias ao ato cirúrgico.
Asunto(s)
Humanos , Femenino , Adulto , Enfermedades del Nervio Accesorio , Microcirugia , NeurilemomaRESUMEN
BACKGROUND: The lateral approach to the craniocervical junction is directed along the atlantal and occipital condyles to the dens. The advantages of the lateral approach compared with the anterior transoral and transnasal approaches are that it provides a sterile field, and anterior decompression and postdecompression fixation can be performed in one procedure. OBJECTIVE: To examine the usefulness of endoscopy as an auxiliary tool during lateral transatlantal odontoidectomy. METHODS: Six cadaver heads, in which the vessels were injected with colored silicone, were dissected using a surgical microscope and 0- and 30-degree endoscopes. A flap incision was chosen to accomplish exposure of the area of the decompression, the occipital squama and adjacent laminae for fixation, and the vertebral artery from C2 to its dural entrance for its stabilization. RESULTS: Study findings revealed that endoscopy adds several advantages to microscopy in the lateral transatlantal approach to the craniovertebral junction in cases of craniovertebral malformation by providing magnification and illumination not limited by corners, thus helping to avert substandard decompression and complications such as dural tears and cerebrospinal fluid leaks; flexibility in surgical positioning of patients; and improved ergonomics that enable the surgeon to complete the procedure in a more efficient, comfortable, and safe manner. CONCLUSION: Endoscopy is a useful adjunct to microscopy in completing lateral approaches to the craniovertebral junction.