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Benign tumors
Published in Rashmi Sarkar, Anupam Das, Sumit Sethi, Concise Dermatology, 2021
The neurofibromas can be solitary or multiple. Multiple neurofibromas are present in several distinct genetic disorders. The two main forms are NF1 (Neurofibromatosis 1 or von Recklinghausen’s disease) and NF2 (Neurofibromatosis 2). It is inherited as an autosomal dominant condition, but 30–50% of patients do not give a family history, suggesting that there is a high rate of new gene mutation.
Genetics in Otology and Neurotology
Published in John C Watkinson, Raymond W Clarke, Louise Jayne Clark, Adam J Donne, R James A England, Hisham M Mehanna, Gerald William McGarry, Sean Carrie, Basic Sciences Endocrine Surgery Rhinology, 2018
The hallmark of neurofibromatosis 2 (NF2) is hearing loss caused by bilateral vestibular schwannomas. Approximately 50% of affected patients have no family history of NF2; therefore these patients represent new germ line mutations in the NF2 gene. This is discussed further in the section on NF2 in this chapter.
Paediatric Neurology
Published in John W. Scadding, Nicholas A. Losseff, Clinical Neurology, 2011
Of the disorders with autosomal dominant inheritance, neurofibromatosis 1 (NF1) affects about one in 3000 individuals, and neurofibromatosis 2 (NF2) around one in 35 000 people. There is almost complete penetrance for NF1, but 30 per cent of cases are new mutations. Both disorders are characterized by growth of neurofibromas, in NF1 in skin and on the optic nerve and in NF2 within the spinal cord and brain, with a predilection for the 8th nerve. NF1 maps to chromosome 17, NF2 to chromosome 22. Specific learning difficulties and attention deficit disorder are common in NF1 with IQ typically lower than unaffected siblings. Epilepsy is more common but probably occurs in less than 5 per cent. Brain imaging in children and adolescents with NF1 frequently identifies ‘unexplained bright objects’ of uncertain significance especially as they may change in size and even disappear over time.
Clinical manifestation, management and prognosis of clear cell meningioma: an evidence-based review
Published in International Journal of Neuroscience, 2023
Masum Rahman, Priyata Dutta, Preeti Agarwala, Samar Ikram, Eram Ahsan, Md Manjurul Islam Shourav, Cecile Riviere-cazaux, Amro Abuleil, Aprajita Milind Bhorkar, Rezaur Rahman Reza, Abu Bakar Siddik
There are no unique symptoms that have been found to be unique for CCM, either intracranial or spinal. Regardless, clinical presentation varied on the basis of the anatomical site of the tumor [6, 10]. Most common symptoms for intracranial CCM are headache or increased intracranial pressure (66.7) followed by limb weakness (25.0), focal neurological deficit (25.0) seizure (16.7), gait disturbance (12.5) [10]. While most common presenting symptoms for spinal CCM are pain (75.0%), followed by paraplegia or quadriplegia (33.3%), sensory disturbance or paresthesia (15.5%) and bowel or bladder dysfunction (10.7%). It usually presents a more acute onset in younger patients where spinal rigidity and tenderness appear early in the disease course [6]. The interval between the onset of symptoms and admission to the hospital varied from 2 weeks to 6 years, with a median of 6 months [5]. A case series of 36 patients stated that the majority were sporadic, and two had neurofibromatosis 2 (NF2). Compression due to tumor was the most common cause of preoperative symptoms in CCM patients. The preoperative period lasted anywhere from one month to three years, with a median of three months. The majority of spinal CCMs were found in the lumbosacral area [12].
Awake craniotomy for assisting placement of auditory brainstem implant in NF2 patients
Published in Acta Oto-Laryngologica, 2018
Qiangyi Zhou, Zhijun Yang, Zhenmin Wang, Bo Wang, Xingchao Wang, Chi Zhao, Shun Zhang, Tao Wu, Peng Li, Shiwei Li, Fu Zhao, Pinan Liu
Neurofibromatosis 2 (NF2) is an autosomal dominant disorder characterized by bilateral vestibular schwannomas. The disorder is genetically defined by a mutation of a tumorsuppressor gene on chromosome 22 coding for merlin, the lack or dysfunction of which leads to multiple nerve sheath tumors. Patients with NF2 always suffer bilateral hearing loss due to the surgical removal, progressive bilateral acoustic tumors, radiation therapy or other reasons [1]. Hearing loss is one of the main factors influencing quality of life and is difficult to handle in this condition. For bilateral auditory nerve injuries or disconnection in these patients, cochlear implant (CI) is not an appropriate option to reconstruct hearing. Auditory brainstem implant (ABI) can restore auditory function by bypassing the auditory nerve and directly stimulating the cochlear nucleus complex (CNC) in the brainstem [2–5]. However, auditory outcomes with ABIs are poor compared with those reported in CI users. Some ABI patients achieve open-set speech perception [6,7], but auditory benefits are limited to enhancing lip-reading for the majority of NF2 patients. Suboptimal placement of an ABI electrode array over the cochlear nucleus may be a crucial reason for poor auditory performance [8].
First report of the efficacy of vestibular rehabilitation in improving function in patients with Neurofibromatosis type 2: an observational cohort study in a clinical setting
Published in Disability and Rehabilitation, 2019
Beatrice Emmanouil, Katherine Browne, Dorothy Halliday, Allyson Parry
Neurofibromatosis 2 (NF2) is a rare autosomal dominant genetic disorder with a birth incidence of one in every 25–33,000 [1] and a prevalence of one in 60,000 individuals [2], which predisposes to the development of multiple benign tumours of the central and peripheral nervous system. The hallmark of NF2 is the growth of bilateral vestibular schwannomas (VS), compressing the vestibulocochlear nerve, and causing sensorineural hearing loss, tinnitus, vertigo, dizziness, and loss of balance. Facial weakness as well as ocular impairment can also occur when the tumour grows to envelop the facial and ocular nerves, further exacerbating the problems of these individuals who are already affected with loss of hearing.