EMERGENCY:Large acoustic neuromas compressing the brainstem can produce acute hydrocephalus and rapid neurological deterioration. Any patient with a known large acoustic neuroma who develops sudden worsening headache, vomiting, or reduced consciousness requires emergency assessment. —call040-46324365immediately — 24 hours, 7 days— 24/7
Acoustic Neuroma in Hyderabad: Unilateral Hearing Loss That Is Not Just Ageing — Diagnosis by MRI and Surgical Expertise of the KIMS Neuroscience team
Expert MRI brain with gadolinium and IAM cuts, pure-tone audiometry and vestibular testing, retrosigmoid / translabyrinthine / middle-fossa microsurgical excision with intraoperative facial nerve monitoring by the KIMS Neuroscience team, Gamma Knife / CyberKnife referral, NF2 multidisciplinary programme, and watchful waiting for small stable tumours — at KIMS Neuroscience, Secunderabad, Hyderabad.
Acoustic neuroma is a benign, slow-growing tumour arising from the Schwann cells of the vestibular portion of CN VIII (the superior vestibular nerve in most cases, despite the name "acoustic" neuroma). It grows within the internal auditory meatus (IAM) and may extend into the cerebellopontine angle (CPA) cistern, compressing CN VII (facial nerve), CN V, cerebellum, and brainstem. The most common initial symptom is unilateral progressive sensorineural hearing loss (SNHL) — often attributed to noise exposure or ageing and not investigated with MRI. Any unexplained asymmetric sensorineural hearing loss or persistent unilateral tinnitus warrants MRI brain with gadolinium and IAM cuts. Bilateral acoustic neuromas = neurofibromatosis type 2 (NF2). KIMS Neuroscience performs CP angle surgery with facial nerve preservation as the guiding surgical principle.
- The MRI rule
- Any unexplained unilateral SNHL or unilateral tinnitus persisting >3 months: MRI brain + gadolinium + IAM cuts. A 30-minute scan provides a definitive answer. Most acoustic neuromas diagnosed at KIMS are in patients who had symptoms for years before investigation.
- Facial nerve preservation
- Intraoperative facial nerve monitoring (continuous EMG) during every surgery. Facial nerve preservation is the primary surgical objective.
- Three approaches
- Retrosigmoid (preferred at KIMS for >2cm: CPA + IAM access without mandatory hearing sacrifice) · Translabyrinthine (widest access, sacrifices cochlear hearing, for deaf ear + large tumour) · Middle fossa (small intracanalicular with good hearing).
- Three management options
- Watch and wait (serial MRI 6–12 monthly for small/elderly/single hearing ear) · Microsurgical excision (KIMS team) · Gamma Knife/CyberKnife (90–95% tumour control, no immediate surgery, non-invasive).
- NF2 bilateral
- Bilateral vestibular schwannomas = NF2 (autosomal dominant, NF2 gene, merlin protein). MRI entire neuraxis. Genetic testing. Goal: preserve at least one hearing ear. ABI (auditory brainstem implant) for bilateral hearing loss.
- The hearing loss that is not ageing
- Unilateral SNHL: worse speech discrimination than pure-tone threshold suggests ("I can hear but cannot understand"). Sudden SNHL in 5–10% of acoustic neuromas from vascular compromise. MRI first, hearing aids second.
- Emergency + contact
- 040-46324365 for brainstem compression/hydrocephalus from large tumour · 040-44885000 for acoustic neuroma assessment and MRI referral.
| Fact | Details |
|---|---|
| Prevalence | 1 per 100,000 per year · Benign, slow-growing · 95% unilateral (sporadic) · 5% bilateral (NF2) · Arises from superior vestibular nerve |
| MRI rule | Any unilateral SNHL or unilateral tinnitus >3 months without clear cause: MRI brain with gadolinium + IAM cuts · "Ice cream cone" shape (tumour from IAM into CPA) is diagnostic |
| Staging | Intracanalicular: confined to IAM · Small (<1.5cm): minimal CPA extension · Medium (1.5–3cm) · Large (>3cm) · Giant: brainstem compression |
| Surgical approaches | Retrosigmoid: KIMS preferred for >2cm · Translabyrinthine: deaf ear/large tumour · Middle fossa: small intracanalicular + good hearing · Intraoperative facial nerve monitoring: all cases |
| Radiosurgery | Gamma Knife/CyberKnife: 90–95% tumour control at 5–10 years · For <2.5–3cm growing slowly · Better hearing preservation than surgery for small tumours |
| NF2 | Bilateral acoustic neuromas = NF2 · Autosomal dominant · Multiple tumours (meningiomas, ependymomas, schwannomas) · ABI for bilateral deafness · Genetic counselling |
| Watch and wait | Criteria: <1.5cm, no growth on 2 serial MRIs, >70 years, single remaining hearing ear · MRI every 6–12 months for 3 years then annually if stable |
About This Condition
Acoustic Neuroma at a Glance
The essential facts that shape how acoustic neuroma is recognised, diagnosed, and treated at KIMS — from the superior-vestibular-nerve origin and the characteristic unilateral hearing loss / tinnitus / imbalance triad, to the NF2 implications of bilateral tumours, the four management options (observation, microsurgery, Gamma Knife, NF2-specific care), and the emergency number for any large-tumour decompensation.
What it is
Acoustic neuroma (vestibular schwannoma) is a benign, slow-growing tumour arising from the Schwann cells of the vestibular portion of the vestibulocochlear nerve (CN VIII). Despite its common name ("acoustic" neuroma, suggesting a hearing nerve origin), it almost always arises from the superior vestibular nerve — the balance component of CN VIII. It grows within the internal auditory meatus (IAM) and may extend into the cerebellopontine angle (CPA) cistern, where it can compress CN VII (facial nerve), CN V (trigeminal nerve), the cerebellum, and ultimately the brainstem.
How it presents
The most common initial symptom is unilateral progressive sensorineural hearing loss (SNHL) — usually gradual, affecting high frequencies first, often attributed to noise exposure or ageing. Unilateral tinnitus (ringing in one ear) frequently accompanies the hearing loss. Imbalance or unsteadiness (from vestibular dysfunction) is the third common feature. The hearing loss is typically noticed when using the phone on the affected ear, or when one ear is covered. Any unilateral sensorineural hearing loss or unilateral tinnitus warrants MRI brain with gadolinium and IAM cuts to exclude acoustic neuroma.
Bilateral = NF2
Bilateral acoustic neuromas are the defining feature of neurofibromatosis type 2 (NF2), an autosomal dominant tumour suppressor gene (NF2 gene, merlin protein) mutation syndrome. Any patient with bilateral vestibular schwannomas, or a unilateral vestibular schwannoma with other features (multiple meningiomas, spinal ependymomas, multiple schwannomas), requires NF2 genetic testing and MRI of the entire neuraxis. NF2 management is more complex: bilateral tumours threaten hearing in both ears, and treatment decisions must weigh deafness risk very carefully.
Treatment options
Watch and wait: serial MRI surveillance every 6–12 months for small, asymptomatic, or slow-growing tumours in older patients. Microsurgical excision: the definitive treatment for growing tumours, large tumours (>2–3cm), and tumours producing significant symptoms. Stereotactic radiosurgery (Gamma Knife, CyberKnife): for tumours under approximately 2.5–3cm that are growing slowly; provides tumour control without immediate surgery; standard of care for older patients and those with single remaining hearing ear.
Emergency
040-46324365
Appointment
040-44885000
The Ear That Could Not Hear the Phone
A 52-year-old software manager in Hyderabad has noticed over the past 3 years that he cannot hear clearly on his right ear when using the mobile phone. He switches the phone to the left ear by habit. There is also a constant high-pitched ringing in the right ear that he has learnt to ignore. At a routine check-up, pure-tone audiometry shows moderate right-sided sensorineural hearing loss with normal left-sided hearing. He is told this is noise-induced hearing loss from his years in an open-plan office. He is given hearing aids.
Two years later, he attends KIMS with new symptoms: he feels unsteady when walking in dim light, and has noticed slight clumsiness of his right hand. A general neurologist examines him: there is mild right-sided facial numbness on testing. KIMS MRI brain with gadolinium and dedicated IAM cuts: a 2.8 cm right-sided CPA mass arising from the internal auditory meatus, with a characteristic “ice cream cone” shape (tumour expanding from the IAM into the CPA cistern), enhancing homogeneously with gadolinium. The radiological diagnosis is vestibular schwannoma (acoustic neuroma).
The case is discussed at KIMS between the KIMS Neuroscience team and the patient: the tumour is 2.8 cm and has caused progressive hearing loss, tinnitus, imbalance, and now facial numbness. Observation is no longer appropriate for a tumour of this size and symptom burden. Microsurgical excision via the retrosigmoid approach is recommended. Intraoperative facial nerve monitoring (continuous recording of facial EMG during surgery to alert the surgeon to any traction on CN VII) is arranged.
Surgery: 5 hours. Near-total resection (small residual cuff of tumour on the facial nerve preserved to protect CN VII). Facial nerve anatomically intact; facial nerve monitoring showed intact facial nerve response throughout. At 24 hours: right-sided facial weakness House-Brackmann grade III (expected post-operative neuropraxia). At 3 months: facial function House-Brackmann grade I (complete recovery). At 6 months: stable residual on MRI — no growth. Annual MRI surveillance planned for the small preserved residual.
Book a Consultation
Speak directly with The KIMS Neuroscience team and the KIMS acoustic neuroma specialist team — neurosurgery, audiology, ENT skull-base, neuroradiology, clinical genetics (NF2), and Gamma Knife referral coordinated under one roof. No referral required. Monday to Saturday.
040-44885000Brainstem compression / hydrocephalus: 040-46324365Clinical Features and Size Classification
The clinical profile of acoustic neuroma spans the characteristic unilateral sensorineural hearing loss with disproportionate speech-discrimination loss, persistent unilateral tinnitus, the slow vestibular adaptation that produces imbalance rather than vertigo, and facial nerve involvement that signals significant tumour size and dominates the surgical strategy.
Unilateral sensorineural hearing loss — the symptom that is always investigated at KIMS
Any unilateral SNHL that cannot be explained by a clear cause (documented noise exposure, genetic hearing loss, established otosclerosis) must be investigated with MRI brain and gadolinium with IAM cuts to exclude acoustic neuroma. The hearing loss of acoustic neuroma is typically slowly progressive, affects speech discrimination before pure tone thresholds significantly, and is the cause of the characteristic complaint: "I can hear sound in that ear but I cannot understand words." An acoustic neuroma can produce sudden sensorineural hearing loss in a small proportion of cases (from vascular compromise to the cochlea), which may be partially reversible if the tumour is treated quickly.
Tinnitus — the persistent unilateral ringing that demands investigation
Unilateral tinnitus (ringing, buzzing, or hissing in one ear) is a cardinal symptom of acoustic neuroma. When a patient presents with tinnitus in one ear only, particularly when combined with asymmetric hearing loss, MRI with IAM cuts is mandatory at KIMS. Bilateral tinnitus (equal in both ears) is less concerning for acoustic neuroma. Many patients with acoustic neuroma have had unilateral tinnitus for years before the diagnosis is made.
Imbalance — from slow vestibular adaptation
The gradual growth of acoustic neuroma allows the vestibular system to adapt slowly to the progressive reduction in vestibular input from the affected ear (central compensation). This means vestibular symptoms (vertigo, disequilibrium) are less dramatic than expected from the degree of vestibular dysfunction documented on formal testing. Instead, patients typically notice imbalance in dim light or on uneven terrain (when visual and proprioceptive compensation is reduced), and increased sensitivity to motion.
Facial nerve involvement — the most important surgical consideration
CN VII (facial nerve) runs in the internal auditory canal immediately adjacent to CN VIII, and is compressed by acoustic neuromas as they grow. Clinically: facial numbness or weakness is typically a sign of significant tumour size (>2–3cm). At KIMS, continuous intraoperative facial nerve monitoring during surgery detects any mechanical stress on CN VII in real time, allowing the surgeon to adjust retraction and dissection to minimise post-operative facial weakness. Facial nerve preservation is the primary surgical objective in acoustic neuroma surgery at KIMS.
Treatment
Management Options at KIMS
Acoustic neuroma management at KIMS is built around three integrated pillars — watch-and-wait with serial MRI for small stable tumours, microsurgical excision by the KIMS Neuroscience team (retrosigmoid, translabyrinthine, or middle fossa approach) for growing or large tumours with mandatory intraoperative facial nerve monitoring, and stereotactic radiosurgery (Gamma Knife / CyberKnife) referral for suitable tumours under 2.5–3 cm.
Watch & wait, by the KIMS Neuroscience team & stereotactic radiosurgery
Watch and Wait with Serial MRI: Appropriate for: tumours <1.5cm; no growth on two successive MRI scans 6 months apart; older patients (>70 years) or those with significant medical comorbidity; patients with single functioning ear (where surgery carries high deafness risk). Serial MRI at KIMS every 6–12 months for the first 3 years, then annually if stable. Growth trigger for intervention: >2mm per year or new/worsening symptoms.
Stereotactic Radiosurgery (Gamma Knife / CyberKnife): Single-fraction or hypofractionated radiation precisely targeted to the tumour. Provides tumour growth control in approximately 90–95% of tumours at 5–10 years. Does not remove the tumour — the tumour typically remains visible on MRI but stops growing. Best for tumours under 2.5–3cm with documented growth in patients who are poor surgical candidates or who prefer to avoid surgery. Hearing preservation is better with radiosurgery than with surgery for small tumours. KIMS coordinates referral to radiosurgery centres for appropriate patients.
Retrosigmoid approach for tumours >2 cm
Retrosigmoid (suboccipital) craniotomy is the KIMS Neuroscience team's preferred approach for tumours >2 cm — provides access to the CPA and IAM without mandatory hearing sacrifice and allows facial nerve monitoring throughout. Near-total resection with a small residual cuff on the facial nerve is used when complete removal would risk CN VII function.
Hearing-preservation approaches in small tumours
Middle fossa approach is used for selected small intracanalicular tumours with good hearing on the affected side. Stereotactic radiosurgery offers better hearing preservation than surgery for small tumours and is preferred in patients with single remaining hearing ear, who are poor surgical candidates, or who prefer non-surgical treatment.
Translabyrinthine for deaf ear / large tumour
Translabyrinthine approach (through the mastoid bone) provides the widest IAM and CPA access but sacrifices cochlear hearing. Reserved for patients with no serviceable hearing in the affected ear and a tumour size that mandates surgery.
Related Conditions
Acoustic neuroma belongs to the family of cranial nerve disorders evaluated and managed at KIMS Neuroscience:
FAQs
Frequently Asked Questions
Unilateral hearing loss. Ringing in one ear. Imbalance in dim light. These are the symptoms of acoustic neuroma — diagnosed with MRI with gadolinium and treated with surgery by the KIMS Neuroscience team, Gamma Knife radiosurgery, or watchful waiting depending on size and growth.
At KIMS Neuroscience, Secunderabad, Hyderabad, facial nerve preservation is the guiding principle of every acoustic neuroma surgery. Call 040-44885000 to book an acoustic neuroma assessment. Emergency: 040-46324365.
International enquiries: info@kimsneurosciences.com