Acoustic Schwannoma: Conditions, Symptoms, Diagnosis, Treatment and Best Options

The symptoms of an Acoustic Schwannoma usually develop gradually over months or years, as the slow-growing tumor progressively presses on nerves. The earliest symptoms are often related to hearing and balance. According to Dr. Jaydev Panchwagh’s insights, common symptoms include:

• Unilateral Hearing Loss: This is the most common initial symptom, usually a gradual, progressive loss of hearing in one ear. It may be accompanied by a feeling of fullness in the ear.
• Tinnitus: A ringing, buzzing, or hissing sound in the affected ear.
• Balance Problems and Dizziness: Unsteadiness, dizziness, or vertigo (a sensation of spinning). These symptoms might be subtle initially but can worsen over time, leading to difficulty walking straight or feeling off-balance.
• Facial Numbness or Weakness: As the tumor grows, it can press on the facial nerve (7th cranial nerve), leading to numbness, tingling, or weakness on one side of the face. In some cases, it can cause involuntary facial twitching (Hemifacial Spasm).
• Headaches: May occur, especially with larger tumors, due to increased pressure within the skull.
• Difficulty Swallowing or Hoarseness: Rarely, very large tumors can press on other cranial nerves (like the glossopharyngeal or vagus nerves), affecting swallowing or speech.

Since many of these symptoms can be caused by other less serious conditions, a specialized evaluation by a neurosurgeon is essential for an accurate diagnosis.

The vast majority of Acoustic Schwannomas develop sporadically, meaning there’s no known cause or family history. They are not linked to diet, environmental factors, or lifestyle choices.

However, a small percentage of Acoustic Schwannomas (about 5%) are associated with a genetic disorder called Neurofibromatosis type 2 (NF2). Individuals with NF2 typically develop bilateral (on both sides) Acoustic Schwannomas, along with other types of tumors on nerves throughout the body.

For sporadic cases, researchers are still investigating the genetic mutations that lead to the formation of these tumors. They are more common in adults, typically appearing between the ages of 30 and 60.

Accurate and timely diagnosis is critical for managing Acoustic Schwannomas, as early detection can significantly influence treatment outcomes and the preservation of nerve function. Dr. Jaydev Panchwagh employs a precise diagnostic approach:

• Detailed Medical History and Neurological Examination: A thorough review of symptoms, especially hearing loss, balance issues, and any facial changes. A comprehensive neurological exam will assess hearing, balance, facial nerve function, and other cranial nerves.
• Audiometry (Hearing Test): This is usually the first test ordered if hearing loss is suspected. It measures the degree and type of hearing loss in each ear.
• Auditory Brainstem Response (ABR) Test: This test measures how the hearing nerve and brainstem respond to sounds and can detect if the nerve pathways are being affected by a tumor.
• Imaging Tests:
  • MRI (Magnetic Resonance Imaging) of the Brain with contrast: This is the gold standard for diagnosing Acoustic Schwannomas. An MRI provides highly detailed images of the internal auditory canal and cerebellopontine angle (CPA) region, allowing Dr. Panchwagh to precisely identify even very small tumors on the vestibulocochlear nerve, determine their size, exact location, and their relationship to surrounding cranial nerves and the brainstem.
  • CT Scan (Computed Tomography): May be used if MRI is contraindicated, but it is less sensitive for detecting small schwannomas.

Combining these diagnostic findings allows Dr. Panchwagh to accurately characterize the Acoustic Schwannoma and plan the most appropriate treatment strategy.

The treatment for an Acoustic Schwannoma is highly individualized, depending on several factors: the tumor’s size, its growth rate, the severity of symptoms (especially hearing loss), the patient’s age, overall health, and the presence of NF2. Dr. Jaydev Panchwagh offers comprehensive management strategies, often involving a multidisciplinary approach.

1. Observation (Watchful Waiting):
   • For very small, asymptomatic, or slow-growing Acoustic Schwannomas, particularly in older patients or those with significant health issues, Dr. Panchwagh may recommend a “watch and wait” approach. This involves regular follow-up MRI scans and hearing tests (audiograms) to monitor the tumor’s growth rate. If the tumor grows or causes problematic symptoms, intervention will be considered.
2. Stereotactic Radiosurgery (SRS):
   • Non-Invasive Radiation: For small to medium-sized Acoustic Schwannomas (typically less than 2.5-3 cm), SRS (such as Gamma Knife or CyberKnife radiosurgery) is an excellent option. This technique delivers highly focused beams of radiation to the tumor in a single session (or a few sessions), aiming to stop its growth or cause it to shrink over time.
   • Benefits: It is non-invasive, has a high rate of tumor control (stopping growth), and often helps preserve useful hearing in the treated ear. Recovery is quick.
   • Considerations: It is not a “removal” of the tumor, and the effects are not immediate; hearing or balance improvements are gradual or aimed at preservation. Close monitoring after SRS is required. Not all tumors are amenable to SRS. Depending on the location, SRS may not be a good option at all. 
3. Surgical Resection (Microsurgical Removal):
   • Definitive Treatment: Surgery is typically recommended for larger Acoustic Schwannomas (especially those causing significant pressure on the brainstem or affecting other nerves), rapidly growing tumors, or when symptoms are severe. The goal is to remove as much of the tumor as safely possible while preserving hearing (if functional) and facial nerve function.
   • Dr. Panchwagh’s Advanced Techniques: Dr. Jaydev Panchwagh is highly experienced in the microsurgical removal of Acoustic Schwannomas, utilizing state-of-the-art technology:
     • High-Power Operating Microscope: Allows for exquisite visualization of the delicate nerves and blood vessels during tumor dissection and removal.
     • Intraoperative Neuromonitoring: This critical technique involves monitoring the function of the facial nerve (7th cranial nerve) and other cranial nerves during surgery to help the surgeon avoid damage and preserve their function. This significantly reduces the risk of post-operative facial weakness or paralysis.
     • Neuro-navigation: Provides real-time, 3D guidance during surgery, enhancing precision and safety.
   • Surgical Approaches: The choice of surgical approach depends on the tumor size, location, and the patient’s hearing status. Common approaches include:
     • Retrosigmoid/Suboccipital Approach: Often used for larger tumors, and can potentially preserve hearing.
     • Translabyrinthine Approach: Used if hearing is already completely lost, offering excellent exposure to the tumor while sacrificing inner ear structures.
     • Middle Fossa Approach: For smaller tumors within the internal auditory canal, with a higher chance of hearing preservation.
   • Benefits: Surgical removal offers immediate mass effect relief, and for completely removed tumors, a very low chance of recurrence. Dr. Panchwagh’s expertise in skull base surgery and intricate cranial nerve procedures positions him as an ideal choice for these challenging cases. Since some part of the tumour may be intentionally left behind so as to preserve the nerve function, it may be necessary to monitor such tumors closely post-operatively and use radiation at a later stage to control the growth.