A vestibular schwannoma, also known as an acoustic neuroma, is a benign tumour that arises from the Schwann cells of the vestibular nerve — the nerve responsible for balance and hearing. It is typically slow-growing, but as it enlarges, it may affect nearby structures including the facial nerve, cochlear nerve, and in larger cases, the brainstem.
These tumours are not cancerous and do not spread to other parts of the body. However, because of their location, they can still cause significant symptoms that affect daily life.
Common Symptoms
Symptoms vary depending on the size of the tumour and how quickly it has grown. They may include:
- Hearing loss, typically on one side
- Tinnitus (ringing or buzzing in the ear)
- Balance difficulties or a sense of unsteadiness
- Facial numbness or tingling
- In larger tumours: facial weakness, headaches, or coordination difficulties
Symptoms often develop gradually, and hearing loss is frequently the first sign — sometimes initially attributed to normal ageing. If you are experiencing unexplained one-sided hearing loss or persistent tinnitus, it is worth seeking a medical evaluation.
How Is It Diagnosed?
Diagnosis typically involves a combination of:
- Audiometry — formal hearing tests to document baseline hearing and speech discrimination
- MRI with contrast — the primary imaging tool, providing detailed views of the tumour, its size, and its relationship to surrounding structures including the facial nerve and brainstem
- CT temporal bone — may be used to assess bony anatomy when surgery is being planned
- Vestibular (balance) testing — to assess the contribution of each ear to balance function
Management Options
Management is individualised and depends on several factors: tumour size, growth rate on serial imaging, symptoms, hearing status, patient age, and overall health. There is no single approach that suits all patients, and your specialist team will discuss the options relevant to your situation.
Observation (Active Surveillance)
For small tumours without significant or progressive symptoms, careful monitoring with periodic MRI scans may be appropriate. Many vestibular schwannomas grow slowly — or not at all — and some patients are managed successfully without active treatment for years. The decision to observe rather than treat is made in close collaboration with your neurosurgeon.
Stereotactic Radiosurgery (e.g. Gamma Knife)
Radiosurgery is a non-invasive treatment that delivers highly focused radiation to the tumour. It does not remove the tumour immediately but aims to halt or slow its growth over time. It is generally considered for smaller tumours — typically less than 2.5–3 cm in diameter — particularly when symptoms are mild or when preservation of neurological function is a priority.
Radiosurgery is usually performed as a day procedure with minimal disruption to daily activities. It does not require a general anaesthetic or surgical incision. Hearing preservation rates and facial nerve outcomes are generally comparable to surgery for appropriately selected smaller tumours, though long-term monitoring with MRI remains necessary.
Microsurgical Removal
Surgical removal is more commonly considered for:
- Larger tumours (generally more than 3 cm)
- Tumours causing significant brainstem compression
- Patients with progressive neurological symptoms
- Cases where radiosurgery is not suitable
Surgery allows for more immediate tumour removal and relief of pressure on surrounding structures. The specific surgical approach used depends on tumour size, its position within the ear canal and surrounding space, hearing status, and your surgeon’s assessment.
Three main surgical approaches are used:
- Translabyrinthine approach — accesses the tumour through the mastoid bone behind the ear, offering direct visualisation of the tumour and facial nerve. This route is typically used when hearing in the affected ear is already significantly impaired, as hearing in that ear is not preserved by this approach. It avoids the need to retract the brain and generally carries a lower risk of cerebrospinal fluid leak.
- Retrosigmoid approach — accesses the tumour from behind the ear through the posterior fossa. This approach preserves inner ear structures and offers the possibility of hearing preservation in selected cases. It is also suitable for larger tumours with significant extension toward the brainstem.
- Middle fossa approach — accesses small tumours confined to the internal auditory canal from above, through the temporal bone. This approach is typically reserved for smaller tumours in patients with good hearing where hearing preservation is a goal.
Your neurosurgeon will recommend the most appropriate approach based on your individual imaging findings, hearing status, and overall clinical picture.
What to Expect During Surgery
Operations typically last several hours, depending on tumour size and surgical approach. General anaesthesia is used throughout.
Intraoperative monitoring is an important part of vestibular schwannoma surgery:
- Facial nerve monitoring — electrodes detect activity in the facial muscles when the nerve is stimulated, helping the surgical team identify and protect facial nerve fibres throughout the procedure
- Auditory brainstem response monitoring — used during hearing-preservation approaches to provide real-time feedback on cochlear nerve function
In some cases, where the tumour is very closely adhered to the facial nerve, a small remnant of tumour may be intentionally left in place to reduce the risk of facial nerve injury. If this occurs, the residual tumour is monitored with regular imaging and may be treated with radiosurgery if it shows growth.
Hospital Stay and Recovery
For patients undergoing surgery at private hospitals in Singapore, the usual hospital stay is approximately 3–5 days, depending on recovery progress and individual factors.
After surgery, patients are monitored for:
- Neurological function — including facial movement, vision, and limb strength
- Balance — dizziness and unsteadiness are common in the days immediately after surgery
- Wound healing — monitoring for cerebrospinal fluid leak or signs of infection
- Hearing — assessed according to the surgical approach used
Recovery varies between individuals. Most patients are able to return to light daily activities within 3–6 weeks. Balance adaptation — the process by which the brain adjusts to reduced vestibular input from the operated side — typically takes longer, and full recovery may take a few months.
Facial Nerve Function After Surgery
Facial nerve outcomes are one of the most closely monitored aspects of vestibular schwannoma surgery. Some degree of facial weakness is common even when the nerve is anatomically preserved, as surgical handling can temporarily affect nerve function.
Recovery, when it occurs, typically takes place over weeks to months. The risk of longer-term facial weakness increases with larger tumours and closer involvement between the tumour and the nerve. Your surgeon will discuss realistic expectations based on your specific tumour characteristics.
If the eye cannot close fully due to facial weakness, eye protection is important to prevent corneal dryness and injury.
Hearing After Surgery
Hearing outcomes depend on the surgical approach used and pre-operative hearing function:
- Translabyrinthine approach: Hearing in the operated ear is not preserved by this technique
- Retrosigmoid and middle fossa approaches: Hearing preservation is possible in selected cases, though it is not guaranteed and rates tend to be lower for larger tumours
Patients who experience hearing loss in one ear generally adapt well over time. Hearing aids including CROS (Contralateral Routing of Signal) systems or bone-anchored devices may be helpful in certain listening environments.
Balance Rehabilitation
Vestibular function from the operated side is typically reduced or lost after surgery. The brain adapts through a process called vestibular compensation — gradually learning to rely on other sensory inputs including the opposite ear, vision, and joint position sense.
Vestibular rehabilitation therapy — a specialised physiotherapy programme — may be recommended to support this process. Starting balance exercises early, often while still in hospital, may help accelerate recovery. Most patients achieve functional balance over time, though individual timelines vary.
Potential Complications
As with any surgery, vestibular schwannoma operations carry risks. Your surgeon will discuss these in detail before any procedure. Potential complications include:
- Cerebrospinal fluid (CSF) leak — fluid surrounding the brain may leak through the surgical site; many cases resolve with conservative management, though some may require additional intervention
- Facial weakness — temporary or longer-term, depending on nerve involvement
- Hearing changes — expected with some approaches; possible with others
- Balance disturbance — universal initially, improves with rehabilitation
- Headache — particularly associated with the retrosigmoid approach; usually improves over months
- Infection or meningitis — uncommon but possible
- Stroke or neurological injury — rare given proximity to critical structures
Multidisciplinary Care
Care for vestibular schwannoma is typically coordinated through a multidisciplinary team. At FeM Surgery, this involves collaboration between neurosurgeons, ENT surgeons, audiologists, and physiotherapists, to support both short-term recovery and long-term outcomes.
This team-based approach allows decisions to be tailored to the whole patient — not just the imaging findings — and ensures continuity of care through the treatment journey and beyond.
Long-Term Follow-Up
Regular MRI surveillance continues after treatment regardless of the approach taken. For patients who have undergone complete surgical removal, imaging monitors for recurrence. For those with intentionally retained tumour remnants, imaging tracks for any growth that may warrant additional treatment.
When to Seek an Evaluation
Consider consulting a specialist if you experience:
- Gradual or sudden hearing loss in one ear without a clear cause
- Persistent tinnitus predominantly affecting one ear
- Persistent balance difficulties or unsteadiness
- Facial numbness, tingling, or weakness
- A previously diagnosed vestibular schwannoma with new or worsening symptoms
- Headaches accompanied by any of the above
Commonly Asked Questions
Do all vestibular schwannomas need surgery?
No. Small tumours without significant symptoms may be managed with active surveillance using serial MRI scans. Many grow slowly or not at all. Your specialist will discuss which management approach is most appropriate for your situation.
How long does recovery take?
Hospital discharge typically occurs within a few days. Most patients return to light activities within 3–6 weeks. Balance adaptation often takes longer — several months in many cases. Individual timelines vary based on tumour size, the surgical approach, age, and overall fitness.
Will I need additional treatment after surgery?
If complete removal is achieved, ongoing MRI surveillance is typically all that is required. If a small tumour remnant is present, imaging monitors for growth, and radiosurgery may be considered if regrowth occurs.
Can the tumour come back after surgical removal?
Gross total removal is associated with low recurrence rates. When some tumour remains intentionally, regular imaging helps detect any changes early.
What if both ears are affected?
Most vestibular schwannomas occur on one side only. Bilateral tumours are rare and are associated with a genetic condition called neurofibromatosis type 2. Treatment planning in these cases requires careful consideration to preserve as much hearing and neurological function as possible.
This article is intended for general educational purposes and should not replace a personalised medical consultation. Please consult a qualified specialist for advice on your individual condition.
Next Steps
If you have been diagnosed with a vestibular schwannoma, or are experiencing symptoms that may suggest one, a specialist evaluation from a neurosurgeon can help clarify your options. The most appropriate management — whether observation, radiosurgery, or surgical removal depends on your individual clinical picture, and there is rarely a single “right answer” without a proper assessment.
