Current Concepts in the Evaluation and Treatment of Neurofibromatosis Type II

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Clinical presentation

Patients affected with NF2 are usually diagnosed between the second and fourth decade, but up to 18% of patients present under the age of 15 years [19]. Up to 41% of patients who eventually develop NF2 do not present with bilateral vestibular schwannomas; therefore, some adult patients can present with unilateral sensorineural hearing loss (SNHL) rather than symmetric or asymmetric bilateral SNHL [10]. The hearing loss is usually progressive, but sudden SNHL can occur. The patient can also

Clinical and genetic screening for neurofibromatosis type II

The evaluation of a patient at risk for developing NF2 should begin with audiometric testing. A T1-weighted, gadolinium-enhanced MRI of the brain and internal auditory canals should be obtained if there is asymmetric hearing loss, or if the hearing is normal and there is a family history or other stigmata of NF2 disease. Some physicians advocate auditory brainstem response and acoustic reflex studies, which can be helpful but should not replace the MRI as a screening procedure because they have

Hearing rehabilitation

Early in the course of NF2, conventional hearing aids may be useful for moderate hearing loss. There are two options for bilateral hearing restoration in severely to profoundly deafened individuals with NF2. Both cochlear implant (CI) and auditory brainstem implants (ABI) can be used in specific situations to provide hearing for the NF2 patient. A CI is used to stimulate auditory neurons in the cochlea and requires preservation of an intact cochlear nerve during tumor removal. Even though the

Treatment

The initial treatment decisions are influenced by tumor size, location, patient age, and hearing status. Early surgical intervention with attempted hearing preservation in NF2 patients, as opposed to delaying tumor removal until after all useful hearing has been lost by tumor compression or invasion, is a greatly debated topic. The authors believe that early detection and treatment of NF2 tumors provides much greater opportunity for hearing preservation [7], [38]. Additionally, they believe

Potential future therapies

The NF2 gene encodes a tumor-suppressor protein product, merlin [12]. It is hoped that understanding merlin's interactions with other proteins, signaling pathways, and regulation of the NF2 gene will lead to the development of novel treatments for vestibular schwannomas. Ultimately, targeted molecular interventions and drug therapies will be designed to stop schwannoma progression or to eradicate preexisting tumors altogether. Such treatments will offer alternatives to the current options of

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References (61)

  • W.R. Kanter et al.

    Central neurofibromatosis with bilateral acoustic neuroma: genetic, clinical and biochemical distinctions from peripheral neurofibromatosis

    Neurology

    (1980)
  • R.L. Martuza et al.

    Neurofibromatosis 2 (bilateral acoustic neurofibromatosis)

    N Engl J Med

    (1988)
  • M.E. Glasscock et al.

    Management of bilateral acoustic tumors

    Laryngoscope

    (1989)
  • V.F. Mautner et al.

    Skin abnormalities in neurofibromatosis 2

    Arch Dermatol

    (1997)
  • D.G.R. Evans et al.

    Neurofibromatosis type 2

    J Med Genet

    (2000)
  • M.E. Baser et al.

    Evaluation of clinical diagnostic criteria for neurofibromatosis 2

    Neurology

    (2002)
  • D.G.R. Evans et al.

    A clinical study of type 2 neurofibromatosis

    Q J Med

    (1992)
  • J.H. Wishart

    Case of tumors in the skull, dura mater, and brain

    Edinburgh Med Surg J

    (1822)
  • W.J. Gardner et al.

    Bilateral acoustic neurofibromatosis: a clinical study and field survey of a family of five generations with bilateral deafness in thirty-eight members

    Arch Neurol Psychiatry

    (1930)
  • M. Ruggieri et al.

    The clinical and diagnostic implications of mosaicism in neurofibromatosis

    Neurology

    (2001)
  • L. Kluwe et al.

    Molecular study of frequency of mosaicism in neurofibromatosis 2 patients with bilateral vestibular schwannomas

    J Med Genet

    (2003)
  • A. Moyhuddin et al.

    Somatic mosaicism in neurofibromatosis 2: prevalence and risk of disease transmission to offspring

    J Med Genet

    (2003)
  • D.G.R. Evans et al.

    Pediatric presentation of type 2 neurofibromatosis

    Arch Dis Child

    (1999)
  • V.F. Mautner et al.

    Spinal tumors in patients with neurofibromatosis type 2: MR imaging study of frequency, multiplicity, and variety

    AJR Am J Roentgenol

    (1995)
  • D.A. Moffat et al.

    Management strategies in neurofibromatosis type 2

    Eur Arch Otorhinolaryngol

    (2003)
  • V.F. Mautner et al.

    The neuroimaging and clinical spectrum of neurofibromatosis 2

    Neurosurgery

    (1996)
  • D.B. Welling et al.

    Acoustic neuroma: a cost-effective approach

    Otolaryngol Head Neck Surg

    (1990)
  • I.A. Zealley et al.

    MRI screening for acoustic neuroma: a comparison of fast spin echo and contrast enhanced imaging in 1233 patients

    Br J Radiol

    (2000)
  • D.B. Welling et al.

    Mutational spectrums in the neurofibromatosis type 2 gene in sporadic and familial schwannomas

    Hum Genet

    (1996)
  • P. Merel et al.

    Screening for germ-line mutations in the NF2 gene

    Genes Chromosomes Cancer

    (1995)
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