What You Need to Know About Acoustic Neuroma (Vestibular Schwannoma)

Acoustic neuroma is a benign tumour on the nerve connecting the inner ear to the brain, which may cause complications such as hearing loss and dizziness. Depending on the tumour's size, it is followed up with regular check-ups or subjected to surgery or radiation. Rehabilitation, especially physical therapy, is also important in regaining balance and coordination.

What is Acoustic Neuroma (Vestibular Schwannoma)?

Acoustic neuroma, or vestibular schwannoma, is a benign tumour on the vestibular nerve, which controls balance and hearing. It causes symptoms like hearing loss, tinnitus, and dizziness as it grows, potentially compressing nearby structures. Treatment for it depends on tumour size and symptoms, ranging from regular monitoring, physiotherapy, and surgical or radiation interventions to manage and reduce the effects.

Causes of Acoustic Neuroma (Vestibular Schwannoma)

The causes of acoustic neuroma are unclear, but it’s believed to result from a mix of genetic and random factors, with some cases linked to NF2.

Genetic Factors: The Role of Neurofibromatosis Type 2 (NF2)

NF2 is a genetic factor related to a condition of bilateral acoustic neuromas that commonly causes tumours in both ears. NF2 tends to occur earlier than other acoustic neuromas, necessitating increased monitoring and treatment and often involving other nerves in the brain and spine.

Environmental Factors

There is no known direct environmental or lifestyle cause for acoustic neuroma. Prolonged exposure to loud noises and radiation has been suggested as a possible risk factor, but studies, including those on cell phone use, remain inconclusive. Ongoing research is in the quest to find possible associations for prevention and early detection.

Sporadic Acoustic Neuromas

Most acoustic neuromas are idiopathic, arising in one ear without a family history. They probably arise from a chance mutation in nerve cells, and prevention is difficult. Regular follow-ups may allow symptoms to be monitored, and intervention may take place early if the tumour begins to grow or symptoms develop.

Types of Acoustic Neuroma (Vestibular Schwannoma)

Acoustic neuromas may be either sporadic, unilateral tumours, without a family history or genetic, or bilateral tumours associated with Neurofibromatosis Type 2 (NF2). Bilateral cases are rarer and tend to present in younger individuals.

Sporadic, Unilateral Acoustic Neuromas

The majority of acoustic neuromas are sporadic and unilateral, found on one side, and do not have a familial or inherited condition. They occur from genetic changes affecting nerve cells, leading to symptoms involving loss of hearing and disturbed balance in the affected ear.

Genetic, Bilateral Acoustic Neuromas

Bilateral acoustic neuromas are associated with Neurofibromatosis Type 2 (NF2), an autosomal dominant condition characterised by a 50% inheritance risk. Affecting both vestibular nerves earlier than those of the sporadic variety, these tumours require close monitoring and complex treatment of hearing and balance issues in both ears.

Signs and Symptoms of Acoustic Neuroma

Acoustic neuromas are known to cause hearing loss, ear fullness, tinnitus, balance issues, and, in some cases, facial paralysis or numbness.

Hearing Loss

Unilateral hearing loss often presents with acoustic neuroma, as the tumour damages the vestibular nerve's hearing pathways. Symptoms included muffled sounds and difficulty understanding speech in noise. Untreated, hearing loss worsened and became permanent. 

Ear Fullness

Ear fullness, a symptom of acoustic neuroma, can be described as pressure or blockage. Such sensations occur during sinus infections or flights. Ear fullness occurs due to compression by a tumour or because of fluid imbalance in the inner ear.

Noise in the Ear (Tinnitus)

One of the most common symptoms of acoustic neuroma is tinnitus, or ringing, buzzing, or hissing sounds in the affected ear due to tumour-induced nerve signal misfiring, which varies from mild to severe.

Balance Problems and Vertigo

Balance issues and vertigo can often result from acoustic neuroma, as this tumour affects the vestibular nerve. When the room begins to spin or tilt, vertigo may be sudden or spasmodic. As the tumour enlarges, the balance problems worsen, making it difficult for even the most competent walker to navigate dark or uneven areas. Similar symptoms often accompany hearing loss or tinnitus.

Other Signs of Acoustic Neuroma

Acoustic neuromas cause facial numbness, tingling, muscle weakness, or partial facial paralysis in advanced cases.

Facial Numbness and Tingling

As the acoustic neuroma grows, it may exert pressure on the facial nerve, resulting in numbness, tingling, and bizarre sensations, especially in the cheek or jaw. These symptoms need an early medical evaluation and treatment.

Facial Twitching and Weakness

The pressure exerted by the acoustic neuroma on the facial nerve may lead to twitching, muscle weakness, and drooping of one side of the face. Facial expressions may become more difficult to control or feel less responsive in some cases.

Swallowing Problems

Swallowing may become problematic if the acoustic neuroma presses on nerves that regulate swallowing. Patients may complain of food sticking or difficulty swallowing, which suggests the tumor is affecting structures beyond the vestibular nerve and receives specific treatment.

Changes in Taste and Tear Production

Acoustic neuroma may interfere with taste and tear production by compressing the facial nerve, thereby interfering with the sensation of taste or with tear glands. These effects cause a metallic taste and dryness from a decrease in tear production.

Acoustic Neuroma (Vestibular Schwannoma) Diagnosis

The diagnosis of acoustic neuroma involves the assessment of symptoms, audiometry, MRI scans, and differential diagnosis to rule out similar conditions.

Hearing Tests and Audiometry

Audiometry tests the ability to hear sounds at different frequencies and volume levels, such as identifying features of hearing loss. In acoustic neuroma, unilateral hearing loss is common. Additional tests include speech discrimination or sensitivity to the presence of loud noises, and MRI is the recommended test to confirm interference of the tumour with the vestibular nerve.

Imaging Techniques: MRI and CT Scans

MRI is the most appropriate imaging modality for seeing tiny acoustic neuromas on the vestibular nerve. MRI offers rich visualisation of soft tissues. If MRI is not accessible, a CT scan may then be used, albeit with less sensitivity. Imaging will, therefore, elucidate the size, location, and progression of the tumour and, hence, treatment decisions.

Differential Diagnosis

Differential diagnosis is used to differentiate acoustic neuroma from other conditions that present similar symptoms, such as Ménière's disease or multiple sclerosis and inner ear infections. Comparing symptoms with test results and scans by doctors determines the cause.

Treatment Options for Acoustic Neuroma (Vestibular Schwannoma)

If symptoms worsen, surgery or stereotactic radiosurgery could be an option for treatment. The goals of treatment are to preserve hearing, alleviate symptoms, and balance the benefits against potential risks based on tumour size and location.

Observation and Monitoring

In the case of small, non-growing acoustic neuromas, the best approach is observation and regular monitoring through MRI scans and hearing tests. It allows physicians to follow up on tumour size and growth to ensure only non-invasive treatment for cases not significantly affecting patients.

Surgical Interventions: Microsurgery and Its Types

Large or rapidly growing acoustic neuromas can be removed surgically with the help of a translabyrinthine, retrosigmoid, or middle fossa approach. Translabyrinthine is better suited for extensive tumours but may have permanent hearing loss, while retrosigmoid aims to preserve hearing, and the middle fossa targets smaller tumours for hearing preservation.

Stereotactic Radiosurgery and Radiation Therapy

Stereotactic radiosurgery, Gamma Knife, is a non-surgical treatment for acoustic neuromas; precise radiation beams destroy the tumour's DNA, halting growth. It is ideal for small-to-medium-size tumours; it avoids the risks of surgery.

Physiotherapy for Post-Treatment Recovery

Physiotherapy assisting in recovering from acoustic neuroma treatment focuses on balance and coordination. Post-surgery or radiation, patients may have dizziness or, muscle weakness, or a problem keeping their balance. The exercises will be adapted to increase stability and strength and help decrease fall risk, with balance training, stretching, and strength-building.

At Physiotattva, we offer a range of support and dedicated care facilities for specialised post-treatment recovery. Reach out to us via call or mails today to know more.

Complications of Acoustic Neuroma

Untreated brain tumours can cause facial paralysis, muscle weakness, and respiratory issues. Surgery carries risks like hearing loss and facial nerve damage.

Pressure on the Brain Stem

An acoustic neuroma continues to grow, in some cases pressing on the brain stem and disrupting basic functions, such as respiration and heart rate. This can cause dizziness, coordination issues, and muscle weakness.

Blockage of Cerebrospinal Fluid (CSF) Flow

Large acoustic neuromas could disturb the flow of cerebrospinal fluid (CSF), creating disruptions in the pressure levels and causing symptoms such as headaches, nausea, and visions. Such a situation can lead to hydrocephalus, which might need intervention.

Risk of Hydrocephalus and Brainstem Compression

Untreated acoustic neuromas can obstruct the flow of cerebrospinal fluid thereby causing fluid accumulation and pressure on the brain stem. Painful changes in vision and loss of coordination could be consequences.

Prognosis and Recurrence Rates

The prognosis for acoustic neuroma mostly hinges on the size, growth rate of tumours, and the treatment selected. Generally, smaller tumours with less growth are followed-up in time and tend to be good. The recurrence is quite variable when the treatment used is surgery or radiation, and a higher number of tumours can have recurrence over time.

Living with Acoustic Neuroma: Coping Strategies and Support

Living with acoustic neuroma involves managing hearing loss, balance issues, and facial numbness, with support from aids, exercises, and loved ones.

Rehabilitation and Therapy Options

Rehabilitation after acoustic neuroma treatment involves physiotherapy for balance and dizziness, occupational therapy for routine adaptation, and speech therapy for facial nerve damage. All these therapies enable patients to recover the strength and coordination to master their symptoms and, in a wide range of structured sessions, actively manage daily activities.

Lifestyle Adjustments

This is in the case where acoustic neuroma requires lifestyle adjustments to manage symptoms. Balance exercises reduce dizziness, and adjustments to workspaces to accommodate hearing can be made. Regular breaks, a healthy diet, and proper rest contribute to overall wellness. Gradual lifestyle adjustments permit individuals to maintain normalcy; stay active; and manage limitations well.

Managing Acoustic Neuroma: Supportive Care by Physiotattva

At Physiotattva, we offer integrative management for acoustic neuroma recovery with over 30 years of experience. We provide physiotherapy, balance improvement, pain relief, and family counselling for specific needs of post-treatment care. We offer customised plans that work best for you. 

At Physiotattva physiotherapy clinics in Bangalore and Hyderabad, you receive personalised care tailored to your specific needs, ensuring effective results and comfort throughout your journey to recovery. 

Don’t wait to start your recovery! Get in touch with Physiotattva for more details! Contact us at +91 89510 47001.

FAQ

What are the treatment options for acoustic neuroma?

Treatment options include regular monitoring, surgery to remove the tumour, and stereotactic radiosurgery for targeted radiation. Choice depends on tumour size, growth rate, and individual health considerations.

Are acoustic neuromas dangerous?

Acoustic neuromas aren’t cancerous but can become problematic as they grow, pressing on nearby nerves or the brain stem, leading to symptoms like hearing loss, balance issues, and other complications if untreated.

What are the main symptoms of acoustic neuroma?

Common symptoms include hearing loss, tinnitus (ear ringing), balance problems, and sometimes facial numbness. Larger tumours may also cause coordination issues and, in rare cases, swallowing difficulties.

Can acoustic neuroma recur after treatment?

Yes, acoustic neuroma can recur after treatment, though it’s rare. Recurrence rates depend on factors like tumour size, treatment type, and regular follow-up checks to monitor for any regrowth.