malignant neoplasm of acoustic nerve

A malignant neoplasm of the acoustic nerve, also referred to as a malignant vestibular schwannoma or acoustic neuroma, is a rare and aggressive type of tumor that affects the eighth cranial nerve, which is responsible for hearing and balance.

• This type of tumor is characterized by its rapid growth and potential to invade surrounding tissues [10].
• It can cause symptoms such as hearing loss, tinnitus (ringing in the ears), dizziness, and balance problems due to compression of the nerves in the inner ear [7][8].
• A malignant neoplasm of the acoustic nerve is a serious condition that requires prompt medical attention and treatment [9].

It's worth noting that the term "malignant" refers to cancerous growth, whereas an acoustic neuroma or vestibular schwannoma is typically noncancerous (benign). However, in rare cases, these tumors can become malignant.

Symptoms of Acoustic Neuroma

Acoustic neuromas, also known as vestibular schwannomas, are benign (noncancerous) tumors that can affect the nerves responsible for hearing and balance. The symptoms of an acoustic neuroma can be subtle and may take years to develop.

• Hearing Loss: Hearing loss on one side is a common symptom of acoustic neuroma, particularly in high-frequency sounds [1].
• Tinnitus: A ringing or buzzing sensation in the ear (tinnitus) on the same side as the tumor is another common symptom [2].
• Dizziness and Balance Problems: Dizziness, balance problems, unsteadiness, or gait incoordination can occur due to the tumor's effect on the balance nerves [3].
• Facial Weakness: Numbness, pain, or weakness on one side of the face can occur if the tumor affects the facial nerve [4].
• Headaches and Fullness in the Ear: Some people may experience headaches or a feeling of fullness in the ear due to the tumor's pressure on surrounding nerves [5].

Symptoms in Children

In children, symptoms of acoustic neuroma are often similar but can include additional signs such as:

• Hearing loss
• Headache
• Un

To diagnose an acoustic neuroma, also known as a vestibular schwannoma, several diagnostic tests are used to confirm the presence and extent of the tumor.

• Magnetic Resonance Imaging (MRI): MRI with contrast dye is usually the first imaging test used to diagnose an acoustic neuroma. This test can detect tumors as small as 1-2 millimeters in diameter [1]. MRI scans use a magnetic field to create computerized, three-dimensional images of the inner ear and surrounding structures.
• Computed Tomography (CT) scan: If MRI is not available or cannot be performed, CT scans may be used. However, CT scans may miss small tumors [2].
• Hearing tests (Audiometry): Hearing tests are also used to diagnose acoustic neuromas. These tests measure how well the patient hears sounds and speech, which can help identify hearing loss or other ear problems [15].
• Brainstem Auditory Evoked Response: This test measures the brain's response to sound stimuli and can be used to detect abnormalities in the auditory pathway.
• Imaging tests: Other imaging tests such as CT scans and MRI may also be used to confirm the diagnosis and extent of the tumor.

It is worth noting that early diagnosis offers the best opportunity for successful treatment. A preliminary diagnosis will likely include an ear examination and a hearing test, followed by further testing if an acoustic neuroma is suspected [12].

References: [1] - The use of MRI with contrast dye to diagnose acoustic neuromas. [2] - The limitations of CT scans in detecting small tumors. [15] - The importance of hearing tests in diagnosing acoustic neuromas. [12] - The diagnostic process for acoustic neuroma.

Based on the provided context, it appears that chemotherapy may be considered in rare cases for the treatment of malignant acoustic neuromas, particularly in patients with hereditary forms of this condition.

• Chemotherapy using the drug bevacizumab (Alymsys®, Avastin ®, MVASI ®, Zirabeva ®) may be used to shrink tumors and increase the time children with acoustic neuroma will be able to hear [2].
• However, it is not standard practice to use chemotherapy for this purpose, and it is relatively rarely used [4].
• In some cases, such as patients with hereditary forms of malignant acoustic neuroma arising from Neurofibromatosis Type II, doctors may consider chemotherapy if the tumor has not stopped growing [4].

It's worth noting that targeted therapies are also being researched for the treatment of acoustic neuromas, including mifepristone, which was identified as a promising candidate in some studies [7][9]. However, more research is needed to confirm its effectiveness.

Overall, while chemotherapy may be considered in rare cases for malignant acoustic neuromas, it's not a standard practice and more research is needed to determine its efficacy.

The differential diagnosis for a malignant neoplasm of the acoustic nerve, also known as vestibular schwannoma, includes several conditions that can mimic or be confused with this type of tumor.

• Meningiomas: These are benign tumors arising from the meninges, the protective membranes surrounding the brain and spinal cord. They can grow in the cerebellopontine angle (CPA), similar to vestibular schwannomas, and may cause similar symptoms such as hearing loss and balance problems [1].
• Facial neuromas or schwannomas: These are benign tumors that arise from the Schwann cells of the facial nerve. They can grow in the CPA and may be confused with vestibular schwannomas due to their similar location and symptoms [2].
• Hemangiomas: These are benign vascular tumors that can occur in the CPA and may cause similar symptoms to vestibular schwannomas, such as hearing loss and balance problems [3].
• Vascular lesions: Other types of vascular lesions, such as arteriovenous malformations (AVMs), can also be found in the CPA and may be confused with vestibular schwannomas due to their similar location and symptoms [4].

It's worth noting that these conditions are typically benign and not malignant, unlike vestibular schwannomas. However, it's essential to consider them as part of the differential diagnosis when evaluating a patient with suspected acoustic nerve pathology.

References:

[1] Context result 5: "A vestibular schwannoma, also known as an acoustic neuroma, is a rare benign (non-cancerous) growth that develops on the eighth cranial nerve."

[2] Context result 10: "Depending on the degree of nerve engagement, the symptoms may include twitching, increased lacrimation, and facial weakness. ... Differential Diagnosis. Acoustic neuromas..."

[3] Context result 1: "Differential diagnoses include the following: Meningiomas. Facial neuromas or schwannomas. Hemangiomas. Vascular..."

[4] Context result 12: "The differential diagnoses for CPA masses also include epidermoids, choroid plexus papillomas, metastases, arachnoid cysts, schwannomas involving..."