Tuesday, March 13, 2018

Vestibular Schwannoma

What is a vestibular schwannoma (acoustic neuroma)?

A vestibular schwannoma (also known as acoustic neuroma, acoustic neurinoma, acoustic schwannoma, or acoustic neurilemoma) is a benign, slow-growing tumor that develops from the nerves that control balance and hearing. Approximately one out of every 100,000 individuals per year develops a vestibular schwannoma.
The tumor arises from an overproduction of Schwann cells—the cells that normally wrap around the nerves to help support and insulate nerves and transmit impulses. As the tumor grows, it affects the hearing and balance nerves, usually causing hearing loss on that side, tinnitus (ringing in the ear), and imbalance while walking. As the tumor grows, it can interfere with the sensations over the face (the trigeminal nerve), causing facial numbness. Vestibular schwannomas can also affect the facial nerve (for the muscles of the face) causing facial weakness or paralysis on the side of the tumor. If the tumor becomes large, it will eventually press against nearby brain structures (such as the brainstem and the cerebellum), which could be life-threatening.

How is a vestibular schwannoma diagnosed?

One sided hearing loss and/or tinnitus and loss of balance/dizziness are early signs of a vestibular schwannoma. Unfortunately, early detection of the tumor is sometimes difficult because the symptoms may be subtle and may be ignored in the early stages of growth. Also, these symptoms are commonly encountered in many middle and inner ear problems. Once the symptoms appear, a thorough ear examination and hearing and balance testing (audiogram) are essential for proper diagnosis. Magnetic resonance imaging (MRI) scans are critical in the early detection of a vestibular schwannoma and are helpful in determining the location and size of a tumor and in planning its treatment.

How is a vestibular schwannoma treated?

There are three options for managing a vestibular schwannoma:
(1) surgical removal,
(2) radiation, and
(3) observation.

Sometimes, the tumor is surgically removed (excised). The exact type of operation done depends on the size of the tumor and the level of hearing in the affected ear. If the tumor is small, hearing may be saved and accompanying symptoms may improve by removing it to prevent its eventual effect on the hearing nerve. As the tumor grows larger, surgical removal is more complicated because the tumor may have damaged the nerves that control facial movement, hearing, and balance and may also have affected other nerves and structures of the brain.

The removal of tumors affecting the hearing, balance, or facial nerves can sometimes make the patient’s symptoms worse because these nerves may be injured during tumor removal.

As an alternative to conventional surgical techniques, radiosurgery (that is, radiation therapy—the “gamma knife” or LINAC based Stereotactic Radiotherapy) may be used to reduce the size or limit the growth of the tumor. Radiation therapy is sometimes the preferred option for elderly patients, patients in poor medical health, patients with bilateral vestibular schwannoma (tumor affecting both ears), or patients whose tumor is affecting their only hearing ear. When the tumor is small and not growing, it may be reasonable to “observe” the tumor for growth with periodic MRI scans.
Bilateral vestibular schwannomas affect both hearing nerves and are usually associated with a genetic disorder called neurofibromatosis type 2 (NF2). Half of affected individuals have inherited the disorder from an affected parent and half seem to have a mutation for the first time in their family. Each child of an affected parent has a 50 percent chance of inheriting the disorder. Unlike those with a unilateral vestibular schwannoma, individuals with NF2 usually develop symptoms in their teens or early adulthood. In addition, patients with NF2 usually develop multiple brain and spinal cord related tumors. They also can develop tumors of other nerves in the brain or elsewhere in the body.

What is the outcome of patients treated for vestibular schwannoma?

Most patients with vestibular schwannoma that undergo treatment (surgery or radiosurgery) go on to lead a normal healthy life with or without some morbidity pertaining to facial nerve function. The outcome following successful vestibular schwannoma surgery is extremely good.

Tuesday, May 9, 2017


What is Hydrocephalus?

Hydrocephalus is the abnormal accumulation of fluid (Cerebrospinal fluid) within the cavities (ventricles) of the brain. Cerebrospinal fluid or CSF is normally produced in the ventricles and absorbed such that there is almost a constant volume of the fluid in a normal person.

When there is an imbalance between the production and absorption of the CSF, it results in Hydrocephalus

Who is at risk of developing Hydrocephalus?

Hydrocephalus can occur at any age depending on the cause. However, it is most common in infants and older children. The exact incidence in India is not known. In the United States, of 1000 babies born, 1-2 develop Hydrocephalus.

What are the symptoms?


  1. Unusually large head
  2. Rapid increase in the size of the head
  3. Bulging or tense fontanelle
  4. Vomiting
  5. Poor feeding
  6. Irritability
  7. Eyes fixed downwards
  8. Delayed milestones
  1. Excessive sleepiness
  2. Irritability
  3. Declining school performance
  4. Headache, vomiting
  5. Double vision or blurred vision
  6. Difficulty in concentrating on routine tasks
  1. Urinary incontinence
  2. Imbalance while walking
  3. Memory loss
How is Hydrocephalus diagnosed?

After a thorough history and physical examination by the attending Neurologist/Neurosurgeon, one of the following tests may be performed to confirm the diagnosis
  1. Ultrasound imaging in newborns and infants
  2. Computed Tomography (CT)
  3. Magnetic Resonance Imaging (MRI)
How is Hydrocephalus treated?

Depending upon the severity and cause of hydrocephalus, your Neurosurgeon may recommend the following 
  1. Ventriculoperitoneal Shunt surgery - This surgery involves inserting a tube in the ventricles of the brain and placing it in the abdomen so that the excess fluid is drained into the abdomen where it is absorbed by the peritoneum
  2. Endoscopic Third Ventriculostomy (ETV) - In this procedure, the neurosurgeon uses a video camera to make a hole in the ventricle so that excess fluid is drained into the subarachnoid space where it is absorbed.
  3. Close observation - In rare cases, when the hydrocephalus is mild and the cause has been treated, one may just closely follow-up the serial imaging. If the cause has been treated, hydrocephalus may resolve on its own