Türk Nöroşirürji Dergisi 2017 , Vol 27 , Num 1
Acoustic Neuromas
Mustafa SAKAR1,M.İbrahim ZİYAL1,
1Marmara Üniversitesi, Tıp Fakültesi, Beyin ve Sinir Cerrahisi Anabilim Dalı, İstanbul, Türkiye Acoustic neurinomas are the most frequent intracranial schwannomas in adults and they usually arise from superior vestibular branch of 8th cranial nerve. They are rare in pediatric population, which are usually bilateral and associated with Neurofibromatosis Type 2 (NF2). They usually present with hearing loss. Although their annual growth rate is thought to be very slow, other symptoms assiciated with bigger tumors include: facial nerve palsy, other cranial nerve dysfunctions, cerebellar compression, hydrocephalus and brainstem compression. Gardner-Robertson scale for hearing evaluation and House-Brackmann scale for postoperative facial nerve functions are appropriate for follow-up of these patients. Yaşargil and Samii classifications are two widely used classifications. Gold standard is contrast-enhanced magnetic resonance imaging (MRI) in diagnosis and cerebellopontine location, oval and welldefined contours, extention into internal acoustic meatus, homogeneous enhancement are typical findings. Conservative treatment, surgical excision and stereotactic radiosurgery are tools in management. Patient age and medical condition, hearing status, other cranial nerve functions, hydrocephalus and brainstem compression must be evaluated when deciding treatment options. Young patients with very small tumors and elder patients with tumors that does not pose fatal danger are good candidates for conservative treatment. Stereotactic radiosurgery is known to be very effective with tumors smaller than 3 cm, but it can also be used with larger tumors. It is far less effective with tumors associated with NF2. Surgical excision can be used for every patient although hearing and facial preservation is best accomplished with tumors smaller than 2.5 cm. Subtotal excision followed by stereotactic radiosurgery is suggested for large acoustic neurinomas recently. Anahtar Kelimeler : Cerebellopontine angle, Acoustic neuroma, Surgery