Hearing Restoration in Neurofibromatosis Type II Patients

Patients with neurofibromatosis type II will eventually succumb to bilateral deafness. For patients with hearing loss, modern medical science technology can provide efficient hearing restoration through a number of various methods. In this article, several hearing restoration methods for patients with neurofibromatosis type II are introduced.

Spectral-domain Optical Coherence Tomography of Combined Hamartoma of the Retina and Retinal Pigment Epithelium in Neurofibromatosis

A 5-year-old girl was diagnosed with neurofibromatosis type 2 (NF-2) due to multiple neurofibromas, cafe-au-lait spots, and schwannomas of the brain. During ophthalmologic evaluation, a posterior subcapsular cataract and a gray-green colored subretinal lesion were found in right eye. Fluorescein angiography (FA) revealed a combined hamartoma of the retina and retinal pigment epithelium (CHRRPE). At age 9, she underwent cataract surgery. At this time FA and spectral-domain optical coherence tomography (SD-OCT) were taken. The SD-OCT showed an elevated hyperreflective mass in the retina with prominent attenuation of the inner and outer retina, but minimal attenuation in the photoreceptor layers. The underlying retina appeared to be disorganized and thick (791 microm). This is the first case report of SD-OCT imaging of a CHRRPE associated with NF-2 in a pediatric patient. By using SD-OCT in this patient, we could obtain detailed tumor characteristics, and SD-OCT may be helpful in the diagnosis and management of CHRRPE.

Merlina y nuevos tratamientos de schwannomas vestibulares en pacientes con neurofibromatosis tipo 2 / Merlin and new treatments for vestibular schwannomas in patients with Neurofibromatosis type 2

Los schwannomas vestibulares son tumores benignos que habitualmente se presentan en forma esporádica y unilateral, pero pueden aparecer de manera bilateral en el contexto de una neurofibromatosis tipo 2 (NF2). En aquellos asociados a NF2 se han identificado mutaciones del gen NF2 que codifica para merlina, una proteína citoplasmática que se localiza primariamente en protrusiones celulares ricas en actina, y en sitios de contacto entre células y matriz extracelular. La evidencia sugiere que merlina ejerce un rol como proteína supresora de tumores ya que regula la cascada de activación de diversos tipos de receptores de factores de crecimiento celular De esta manera, el déficit de merlina provoca un patrón de proliferación celular aumentado, alteraciones del citoesqueleto, apoptosis disminuida, y un incremento de la adhesión a la matriz extracelular. Se han desarrollado terapias clínicas para la NF2 con anticuerpos monoclonales e inhibidores dirigidos contra distintas moléculas involucradas en las cascadas de señalización celular moduladas por merlina. En este artículo se revisan y discuten los mecanismos celulares dependientes de merlina y los diversos estudios clínicos y experimentales que se han probado en pacientes con NF2.

Vestibular schwannomas are benign tumors that may occur bilaterally in the context of neurofibromatosis type 2 (NF2). A mutation in the NF2 gene coding for merlin protein has been identified in those cases associated with NF2. Merlin is a cytoplasmic protein localized in actin rich cell protrusions, and near contact sites between cells and extracellular matrix. The evidence suggests that merlin plays a role as tumor suppressor protein, regulating the activation cascade of different types of receptors for cell growth factors. Thus, merlin deficiency causes a pattern of increased cell proliferation, cytoskeletal alterations, decreased apoptosis and increased cell adhesion to the extracellular matrix. Several clinical therapies have been developed for NF2 patients including monoclonal antibodies and inhibitors directed against different molecules involved in cell signaling cascades modulated by merlin. In this article we review and discuss cellular mechanisms dependent of merlin and some clinical and experimental studies that have been studied in patients with NF2.

Fractionated stereotactic radiotherapy for bilateral vestibular schwannomas associated with neurofibromatosis type 2: early experiences in Ramathibodi Hospital.

PURPOSE: To evaluate the rates of tumor control and useful hearing preservation in patients with bilateral vestibular schwannomas (VSs) associated with neurofibromatosis type 2 (NF-2) treated with fractionated stereotactic radiotherapy (FSRT). MATERIAL AND METHOD: From August 1998--December 2002 there were 5 patients with NF-2 who underwent FSRT (Linac-based system) for bilateral CP angle tumors. Median age was 28 (18-47) years. Median tumor volume was 5.4 (2.2-9.4) cc. Eight lesions received a marginal dose of 44.2-59.9 (median = 46.2) Gy in 25-33 fractions. The other 2 lesions received 4.4 and 4.9 Gy/fraction for 6 fractions in 3 and 2 weeks. Median follow-up was 19 (14-44) months. RESULTS : Radiographic and clinical tumor control rate was 90%. One lesion progressed at 7 months after FSRT and was completely resected Of the 5 lesions with Gardner-Robertson class I-II hearing before FSRT 2 (40%) retained useful hearing at the last follow-up. One patient had left facial spasm at 10 months after FSRT which gradually improved. No patient had facial palsy, facial numbness or pain. CONCLUSIONS : FSRT provided good tumor control and hearing preservation rate in NF-2 patients with minimal morbidity. However, a longer follow-up is needed to evaluate long term results.

Mixed tumour of schwannoma and meningioma in a patient with neurofibromatosis-2 : a case report.

The co-existence of schwannoma and meningioma as a mixed intracranial tumour is uncommon and so far only eight cases have been published in the literature. Because of rarity, we report a unique case of mixed tumour having schwann cell and meningeal components, in a patient with neurofibromatosis type -2 (NF-2). The possible mechanisms for the occurrence of these mixed tumours are discussed.

Association of lower cranial nerve schwannoma with spinal ependymoma in ? NF2.

A 15 year old male, who had earlier been operated for intraspinal intramedullary ependymoma, subsequently developed a right cerebello pontine (CP) angle mass. A diagnosis of right CP angle ependymoma was considered, in view of established histology of previously operated spinal lesion. Histopathological examination of the well defined extra-axial mass, which was attached with ninth cranial nerve, however revealed a schwannoma. A diagnosis of Neurofibromatosis-2 (NF2) is strongly suspected, because of well established fact, that the spinal ependymomas may have association with lower cranial nerve schwannomas in NF2. Cranial and spinal MRI screening for early diagnosis of associated, asymptomatic lesions, in suspected cases of NF2, particularly in children, is recommended.

Experiência em 115 casos de cirurgia para exérese de neurinoma do acústico / Experience in 115 cases of acoustic neurinoma exeresis surgery

Foram estudados 115 pacientes com neuroma de acústico, entre janeiro de 1986 e agosto de 1994, submetidos à exerese pelo mesmo cirurgiäo, atendidos no Hospital das Clínicas da Faculdade de Medicina da Universidade de Säo Paulo e em clínica privada. Säo apresentados os achados clínicos e diagnósticos. A via translabiríntica foi utilizada em 87 por cento dos caso. Quando a preservaçäo da audiçäo foi aventada, foram adotadas as vias fossa média ou retrolabiríntica. Apesar do diagnóstico precoce, o número de pacientes possíveis de preservaçäo da audiçäo permanece limitado. Estes resultados enfatizam as vantagens da via translabiríntica, oferecendo maior segurança para o nervo facial e morbilidade. A via retrolabiríntica é técnica com grande futuro para a preservaçäo da audiçäo. Na nossa série, 50 por cento dos pacientes tiveram boa preservaçäo da audiçäo

Neurofribroma plexiforme de colon transverso: relato de caso / Large bowel plexiform neurofibroma: a case report

Tumores neurogenicos de colon sao raros na populacao geral, mas podem ocorrer em 11 a 25 por cento dos pacientes com doenca de von Recklinghausen . Apresentamos o caso de uma paciente de 24 anos de idade com neurofibroma plexiforme do intestino grosso cuja manifestacao inicial caracterizou-se por aparecimento de massa no hipocondrio e flanco esquerdos. A paciente nao apresentava, ao exame fisico, sinais de neurofibromatose