Acoustic neuromas occur in two forms: sporadic and those associated with Neurofibromatosis Type II (NF II).
Approximately 95% of all acoustic neuromas are sporadic cases and are unilateral (affecting one ear). Patients with sporadic acoustic neuromas tend to begin having symptoms in middle age with the average being around fifty years old at diagnosis.
In contrast, those tumors associated with NF II are bilateral (affecting both ears) and account for approximately 5% of acoustic neuroma patients. NF II is a rare, genetic condition that affects one in 100,000 people in the United States. Patients with NFII develop benign tumors on both auditory nerves and may have to have both hearing nerves severed through tumor removal. Patients with NF II present at a younger age averaging around thirty years old when they first develop symptoms.
Email : neuro@braintumors.in
Saturday, January 1, 2011
Diagnosis of Acoustic Neuroma
After patients have received routine auditory tests that show loss of hearing and speech discrimination (hearing sound but not understanding what is being said), the hearing care provider may perform an auditory brainstem response test (ABR, BAER or BSER). This test provides information on the passage of sound information along the path from the ear to the brain. The results may indicate that the acoustic nerve is not functioning optimally. If there is an abnormality in the ABR test, a detailed imaging test such as a CT (also called CAT) Scan or MRI is typically ordered.
A CT (CAT) Scan stands for Computerized (Axial) Tomography. The CT scanning device takes x-rays from many different angles and uses a computer to assemble them into a series of cross sections or 'slices' to provide a detailed look at the inside of the body. The CT Scan is painless but sometimes makes patients uncomfortable because they feel closed in during the time in which they are within the scanning device. The CT Scan has proven to be effective in locating acoustic neuromas, although small tumors that are still confined to the internal auditory canal may not show up on standard CT Scans. To assist in providing the clearest possible scan, for some brain scans, the patient may be given an injection of 'contrast medium' dye before the scan begins to make the images clearer.
MRI stands for Magnetic Resonance Imaging. An MRI Scan is a radiology technique that uses magnetism, radio waves, and advanced computer technology to produce images of body structures. The image and resolution produced by MRI is very detailed and can detect tiny changes of structures within the body. In the case of diagnosis for acoustic neuroma, gadolinium, a contrast agent, is used to increase the accuracy of the images. Gadolinium enhances the tumor making it easier to see. An MRI scan is a painless scan that has the advantage of avoiding x-ray radiation exposure and no known history of side effects.
Email : neuro@braintumors.in
A CT (CAT) Scan stands for Computerized (Axial) Tomography. The CT scanning device takes x-rays from many different angles and uses a computer to assemble them into a series of cross sections or 'slices' to provide a detailed look at the inside of the body. The CT Scan is painless but sometimes makes patients uncomfortable because they feel closed in during the time in which they are within the scanning device. The CT Scan has proven to be effective in locating acoustic neuromas, although small tumors that are still confined to the internal auditory canal may not show up on standard CT Scans. To assist in providing the clearest possible scan, for some brain scans, the patient may be given an injection of 'contrast medium' dye before the scan begins to make the images clearer.
MRI stands for Magnetic Resonance Imaging. An MRI Scan is a radiology technique that uses magnetism, radio waves, and advanced computer technology to produce images of body structures. The image and resolution produced by MRI is very detailed and can detect tiny changes of structures within the body. In the case of diagnosis for acoustic neuroma, gadolinium, a contrast agent, is used to increase the accuracy of the images. Gadolinium enhances the tumor making it easier to see. An MRI scan is a painless scan that has the advantage of avoiding x-ray radiation exposure and no known history of side effects.
Email : neuro@braintumors.in
Signs & Symptoms of Acoustic Neuroma
In the majority of patients, the first symptom of acoustic neuroma is a reduction of hearing in one ear. This hearing loss is often accompanied by tinnitus, sound in the ear that has no externally audible source, and is usually subtle and slow in progression. There may also be a feeling of fullness in the affected ear. These early symptoms are sometimes mistaken for normal changes of aging, delaying diagnosis.
If you are experiencing any of these symptoms, we urge you to consult a physician so that a diagnosis can be established. If acoustic neuroma is diagnosed, early management is vital to your continued health.
Email: neuro@braintumors.in
Because the acoustic neuroma originates in the balance portion of the eighth nerve, a patient may experience unsteadiness and problems with balance as the tumor grows. Larger tumors can press on the trigeminal nerve causing facial numbness and tingling, which can be either occasional or constant.
Severe symptoms such as headaches, staggering and mental confusion can indicate an increase of intracranial pressure. Immediate attention is required as this pressure can be a life-threatening complication.If you are experiencing any of these symptoms, we urge you to consult a physician so that a diagnosis can be established. If acoustic neuroma is diagnosed, early management is vital to your continued health.
Email: neuro@braintumors.in
Acoustic Neuroma
An acoustic neuroma is a benign (non-cancerous) fibrous tissue growth that arises from the balance nerve (also called the eighth cranial nerve or vestibulocochlear nerve ) that leads from the brain to the inner ear. Acoustic neuromas are non-malignant, meaning that they do not spread to other parts of the body. An acoustic neuroma is sometimes also called a vestibular schwannoma or neurolemmoma.
Because acoustic neuromas are located deep inside the skull and are adjacent to vital brain centers in the brain stem, as these tumors grow, the affect surrounding structures in the brain that control vital functions. The brain is not invaded by the acoustic neuroma, but the tumor pushes on the brain as it enlarges. As the acoustic neuroma grows, it typically first affects a patient's hearing because it protrudes from the internal auditory canal into an area behind the temporal bone. Larger acoustic neuromas can press on another nerve in the area, the trigeminal nerve, which is the nerve affecting facial sensation. When large acoustic neuromas cause severe pressure on the brainstem and cerebellum of the brain, vital functions that sustain life can be threatened.
In the majority of cases, acoustic neuromas grow slowly over a period of years. In other cases, the growth rate is more rapid and patients develop symptoms at a faster pace. Usually the symptoms are mild and many patients are not diagnosed until some time after their acoustic neuroma has developed. Many patients also exhibit no tumor growth over a number of years when followed by yearly MRI scans.
Acoustic neuromas account for approximately 6% of all brain tumors. These tumors occur in all races of people and have a slightly higher occurrence in women. Most acoustic neuromas occur spontaneously without any evidence of heredity and are diagnosed in patients between the ages of 30 to 60.
Email: neuro@braintumors.in
Because acoustic neuromas are located deep inside the skull and are adjacent to vital brain centers in the brain stem, as these tumors grow, the affect surrounding structures in the brain that control vital functions. The brain is not invaded by the acoustic neuroma, but the tumor pushes on the brain as it enlarges. As the acoustic neuroma grows, it typically first affects a patient's hearing because it protrudes from the internal auditory canal into an area behind the temporal bone. Larger acoustic neuromas can press on another nerve in the area, the trigeminal nerve, which is the nerve affecting facial sensation. When large acoustic neuromas cause severe pressure on the brainstem and cerebellum of the brain, vital functions that sustain life can be threatened.
In the majority of cases, acoustic neuromas grow slowly over a period of years. In other cases, the growth rate is more rapid and patients develop symptoms at a faster pace. Usually the symptoms are mild and many patients are not diagnosed until some time after their acoustic neuroma has developed. Many patients also exhibit no tumor growth over a number of years when followed by yearly MRI scans.
Acoustic neuromas account for approximately 6% of all brain tumors. These tumors occur in all races of people and have a slightly higher occurrence in women. Most acoustic neuromas occur spontaneously without any evidence of heredity and are diagnosed in patients between the ages of 30 to 60.
Email: neuro@braintumors.in
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