Acustic neurinoma. report a case.

Authors

Dr. med. Jorge Said Martinez (Mexico D.F., Mexico)
Dr.med. Alfonso Izita (Mexico D.F., Mexico)

Proceedings

XXXIII Congress of the NES - Bad Kissingen - Germany

Topics

Neurootology
Equilibrium
Diseases
Neurootology
Equilibrium
Neurootology
Neurootologic therapy
Neurootology
Neurootology
Neurootologic therapy
Surgery

Keywords

Acustic nerinom, Hipoacusia, Tinnitus, Vertigo.

Download

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Abstract

By Definition Acoustic Neurinoma is a benign tumor that may develop on the hearing and balance nerves near the inner ear. The tumor results from an overproduction of Schwann cells – small, sheet-like cells that normally wrap around nerve fibers like onion skin and help support the nerves. When growth is abnormally excessive, Schwann cells bunch together, pressing against the hearing and balance nerves, often causing gradual hearing loss, tinnitus and dizziness. If the tumor becomes large, it can interfere with the facial nerve, causing partial paralysis, and eventually pressing against brain structures, becoming life-threatening. There are two types of acoustic neurinomas: Unilateral neurinomas account for approximately 5-8 percent of tumors inside the skull. Symptoms may develop at any age, but usually occur between the ages of 30 and 60 years. Bilateral acoustic neurinomas, affect both ears, are hereditary. Inherited from one’s parents, this tumor results from a genetic disorder known as neurofibromatosis-2 (NF2). Scientists believe that both types of acoustic neurinoma form following a loss of the function of a gene on chromosome 22.

The diagnosis must be early, an acoustic neurinoma is key to preventing its serious consequences. Unfortunately, early detection of the tumor is sometimes difficult, because the symptoms may be subtle and may not appear in the beginning stages of growth. Also, hearing loss, dizziness, and tinnitus are common symptoms of any middle and inner ear problems. Therefore, once the symptoms appear, a thorough ear examination and hearing test are essential the study the vestibular function through of vestibuloespinal, retinalocular, vestibuloocular systems in the Cranio-Corpo-Graphy (CCG), the Test of Balance(TOB) and the Computarized Electronystagmography (CNG). In order to determine and orientate a better vestibular diagnosis. Auditory Evoked Potentials, Computerized tomography(CT) and magnetic resonance imaging (MRI) are helpful in determining the location and size of a tumor and also in planning its removal.