Glossary

Once diagnosed with NF2, there will be many, unfamiliar terms that you may come across. Below is a list of some common words and definitions related to NF2.

A   B   C   D   E   F   G   H   I  J  K   L   M   N   O   P   Q   R   S   T   U  V  W  X  Y  Z

A

Acoustic Neuroma (AN)
A benign tumor developing on the hearing and balance nerves near the inner ear.
Auditory Brainstem Implant (ABI)
A small complex electronic device that is surgically placed (implanted) against the brain stem that can restore some level of hearing when the cochlear nerve has been damaged or severed. during an acoustic neuroma removal, commonly referred as an ABI.
Auditory Brainstem Response (ABR)
A physiological measure of the brainstem’s response to sound. It tests the integrity of the hearing system from the ear to the brainstem by measuring the length of time for signals from sound to be detected by the brain.
Artificial Tears
Eye drops used to provide more moisture for treatment of dry eyes. Some types of Artificial tears include Refresh™Celluvisc, Thera Tears, and Refresh™ Liqui-Gel. These are just a few.
Astrocytoma
A tumor that begins in the brain or spinal cord in small, star-shaped cells called astrocytes.
Autosomal Dominant
Autosomal dominant means that only one copy of a gene, inherited from either the mother or the father, needs to have the mutation for the child to have the disorder. All of the chromosomes except the sex chromosomes are autosomes.

B

Benign Tumor (BT)
A benign tumor is a noncancerous growth that does not spread to other parts of the body. Benign tumors can cause problems, however, depending on the number of tumors, where they grow, and the rate of growth.

C

Cavernous Sinous
A large channel of venous blood creating a “sinus” cavity bordered by the sphenoid bone and the temporal bone of the skull. The cavernous sinus is an important structure because of its location and its contents which include the third cranial (oculomotor) nerve, the fourth cranial (trochlear) nerve, parts 1 (the ophthalmic nerve) and 2 (the maxillary nerve) of the fifth cranial (trigeminal) nerve, and the sixth cranial (abducens) nerve.
Celluvisc
An over-the-counter eye drops for dry eye. They are thicker than artificial tears, so they stay in the eye longer without running. Note, the viscous texture will make vision blurry.
Cerebellum
The cerebellum is a region of the brain that plays an important role in the integration of sensory perception, coordination and motor control. In order to coordinate motor control, there are many neural pathways linking the cerebellum with the cerebral motor cortex (which sends information to the muscles causing them to move) and the spinocerebellar tract (which provides proprioceptive feedback on the position of the body in space). The cerebellum integrates these pathways, like a train conductor, using the constant feedback on body position to fine-tune motor movements.
Cerebral edema
It is an excess accumulation of water in the intracellular and or extracellular spaces of the brain.
Cerebral spinal fluid
Is a clear bodily fluid that occupies the subarachnoid space an the ventricular system around the inside of the brain. Essentially the brain floats in it.More specifically the CSF occupies the space between the arachnoid mater(the middle layer of the brain cover, meninges) and the pia mater( the layer of the meninges closest to the brain.) Moreover it constitutes the content of all intra-cerebral(inside the brain, cerebrum) ventricles, cistems and sulsi( singular sulcus) as well as the central canal of the spinal cord.
Chromosome 22
The chromosome containing the faulty gene which causes NF2.
Chromosomes
Chromosomes are structures located in the nucleus of the cell that contain our genetic material (genes). Humans have 23 pairs of chromosomes: half of each pair is inherited from our mother, and the other half from our father.
Cochlear Implant (CI)
A small complex electronic device that is surgically placed (implanted) within the inner ear to help persons with certain types of deafness to hear. The hearing nerve must be intact to be considered for a cochlear implant.
CINE MRI
Cine MRI (as in cinema) is taken the same way a traditional MRI is, with the addition of either a wristband or EKG leads on the patient’s chest to measure the heart rate. see Also Magnetic Resonance Imaging
Computed Tomography
Computed tomography is a procedure that uses x-rays and computer technology to produce cross-sectional images of the body that are more detailed than traditional x-ray images. Also known as a CAT scan.
Congenital
Congenital refers to a condition that is present at birth.
Craniotomy
A craniotomy is a surgical operation in which part of the skull, called a bone flap, is removed in order to access the brain. Craniotomies are often a critical operation performed on patients suffering from brain lesions or Traumatic Brain Injury (TBI), and can also allow doctors to surgically implant deep brain stimulator’s for the treatment of Parkinson\’s, epilepsy and cerebellar tremor. They are also widely used in neuroscience for extracellular recording, brain imaging, and for neurological manipulations such as electrical stimulation and chemical titration.
Cyst
A cyst is a closed sac of air, fluid or semisolid material.

D

Debulking
Debulking is the surgical removal of part of a malignant tumor which cannot be completely excised, so as to enhance the effectiveness of radiation or chemotherapy. It is used only in specific malignancies, as generally partial removal of a tumor is not considered a worthwhile intervention. Ovarian carcinoma and some types of brain tumor are debulked prior to commencing radio- or chemotherapy.
Deoxyribonucleic Acid (DNA)
DNA is made up of molecules that encode all the instructions necessary for a living organism to grow. Two long strands of DNA make up the familiar spiral-shaped double helix.
Dexamethasone
Dexamethasone is a potent synthetic member of the glucocorticoid class of steroid hormones. It acts as an anti-inflammatory and immunosuppressant. Its potency is about 20-30 times that of hydro cortisone and 4-5 times of prednisone.
Diamox
Etazolamide, sold under the trade name Diamox, is a carbonic anhydrase inhibitor that is used to treat glaucoma, epileptic seizures, benign intra cranial hypertension (pseudo tumor cerebri), altitude sickness, cystinuria, and dural ectasia. Acetazolamide is available as a generic drug and is also used as a diuretic.
Diploid Neoplasm
A tumor (neoplasm) with a diploid number of chromosomes — that is, with a karyotype that is equivalent to that of a normal cell, with 23 chromosome pairs.

E

Electrocardiogram (ECG, EKG)
An electrocardiogram is a noninvasive procedure that measures the heart’s electrical activity.
Electrocochleography
A test that measures the electrical potentials generated in the inner ear in response to stimulation by sound. Electrocochleography may be done, for example, to confirm the diagnosis of Ménière disease. Abbreviated ECochG (or ECoG).
Electroencephalogram (EEG)
An electroencephalogram is a noninvasive procedure to chart electrical impulses of the brain. An EEG is used to help locate the origins of seizures.
Electromyogram (EMG)
A test used to detect abnormal muscle electrical activity that can occur in many diseases and conditions, most often performed when patients have unexplained muscle weakness. This test involves using electrodes to send electric signals through nerves.
Encephalomalacia
A non-specific term that literally means “softening of the brain”. may be caused by either some pathological neurological process or compression of the brain, either by a tumor or secondary to surgery. For example, it is difficult to avoid encephalomalacia in the cerebellar region when a posterior fossa approach is used in AN surgery.
ENT
Ear, Nose & Throat Doctor
Ependymoma
A type of brain tumor derived from the cells that line the cavities within the ventricles of the brain and the central canal of the spinal cord.

F

Facial nerve paralysis
Facial nerve paralysis is a common problem that involves the paralysis of any structures innervated by the facial nerve. The pathway of the facial nerve is long and relatively convoluted, and so there are a number of causes that may result in facial nerve paralysis. The most common is Bell’s palsy, an idiopathic disease that may only be diagnosed by exclusion. Primary jugular foramen (JF) tumor, such as glomus jugular tumor or JF schwannoma, may manifest as a lower cranial nerve deficit; in addition, it can be accompanied by deafness or vertigo if it affects the cranial nerve (CN) VIII. Recently, we encountered JF schwannoma 1 and glomus jugular tumor 1. Both cases invaded the adjacent cerebellopontine angle, leading to cochlea-vestibular deficits prior to the operation. After surgery, recovery of the audio vestibular function, including hearing, auditory brain stem response and caloric response, was anticipated in both patients. Therefore, cochlea-vestibular deficits in JF tumors can be attributed to compression neuropathy, rather than tumor infiltration.
Fibromygalia
A syndrome characterized by chronic pain, stiffness, and tenderness of muscles, tendons, and joints without detectable inflammation.
Fractionalized Stereotactic Radiosurgery (FSR)
Stereotactic radiosurgery is the very precise delivery of radiation to a brain tumor with sparing of the surrounding normal brain. To achieve this precision, special procedures for localization of the brain tumor are necessary. These tools include the stereotactic frame, the CT or MRI scanner, a computerized system for calculating the radiation dose to the brain tumor, and a precise system for delivering the radiation to the brain tumor. Stereotactic radiosurgery offers an important alternative to more invasive treatments for many brain tumors. The role of radiosurgery vs. surgery is determined by many factors. These include the size of the brain tumor, location, how rapidly the symptoms arose, how ill the patient may be (If the patient is very ill, surgery may offer more rapid resolution of the tumor), and the histology (type) of the brain tumor.

G

Gamma Knife (GK)
A type of highly focused radiation therapy. Can also be fractionated (dosage shots over a span of time instead of a single shot).
Gene
A gene is a unit of DNA that codes for the formation of a specific protein. Genes are the fundamental units of heredity. Genes come in pairs: one half of each pair is inherited from our mother, and the other half from our father.
Genetic Counselor
A genetic counselor is a health care professional who has advanced degrees in medical genetics and counseling. Genetic counselors are trained in discussing the genetic components of conditions and genetic test results.
Genetic Disorder
A genetic disorder is a medical condition caused by permanent changes, or mutations, in the DNA sequence of a gene or a number of genes or chromosomes.
Genetic Mutation
A mutation is a permanent change in DNA. Mutations can be inherited or can occur spontaneously.
Geneticist
A geneticist is a medical doctor who specializes in the diagnosis and care of individuals with genetic disorders.
Germ Line
Germ line refers to the body’s reproductive cells, either the egg or the sperm.
Glial Cell
A glial cell is a specialized cell that surrounds nerve cells providing structural and metabolic support. It is estimated that glial cells outnumber neurons by as much as 50 to 1. Also known as neuroglia or glia.

H

House Ear Institute (HEI)
Located in Los Angeles, California, USA They are the original developers of the Auditory Brain stem Implant and have tremendous experience both removing Acoustic Neuromas and placing the Implant.
Hydrocephalus
Hydrocephalus is a buildup of spinal fluid in the ventricles of the brain, causing intra cranial pressure.

L

Lacrilube
An over-the-counter ointment for dry eye treatment. A.K.A. “Night Goop”.
Laminectomy
Laminectomy is a spine operation to remove the portion of the vertebral bone called the lamina. There are many variations of laminectomy, in the most minimal form small skin incisions are made, back muscles are pushed aside rather than cut, and the parts of the vertebra adjacent to the lamina are left intact. The traditional form of laminectomy (conventional laminectomy)excises much more than just the lamina, the entire posterior backbone is removed, along with overlying ligaments and muscles. The usual recovery period is very different depending on which type of laminectomy has been performed: days in the minimal procedure, and weeks to months with conventional open surgery.

M

Magnetic Resonance Imaging (MRI)
Magnetic resonance imaging is a noninvasive procedure that uses radio waves and magnetic fields to produce images of body tissue.
Meckel’s Cave
A pocket of dura matter (the outermost layer of the meningeal membranes) located near the medial (innermost) end of the petrous portion of the temporal bone– the bony housing at the base of the cranium that contains the inner ear. Meckel’s Cave contains the trigeminal ganglion– the nerve root of the fifth cranial nerve.
Meningioma
A common type of slow growing, usually benign brain tumor that arises from the protective covering of the brain and spinal cord.
Micromole
A mole is a measure of units, not weight. One mole = 6.023 x 10^23 (10 to the 23rd power) units – also known as Avogadro’s number. It is used in chemistry to establish atomic or molecular weight. For example, 1 mole of carbon = 12 grams. If you look at a periodic table, you’ll see carbon has an atomic weight of 12. A mole of water would be 18 grams (2 grams hydrogen + 16 grams oxygen). A micromole is one millionth of a mole.
Middle Fossa
Approach A surgical approach for Acoustic Neuroma where an incision is made in the scalp above the ear.

N

Neuro-ophthalmologist
A neuro-ophthalmologist is a physician (neurologist or ophthalmologist) specializing in diseases affecting vision that originate from the nervous system.
Neurofibromatosis (NF)
Neurofibromatosis is a genetic disorder caused by a mutation to the NF1 or NF2 gene. Neurofibromatosis 1 (NF1) is characterized by multiple benign tumors and patches of skin pigmentation called café au lait spots. Neurofibromatosis 2 (NF2) is characterized by tumors of the hearing and balance nerve.
Neurologist
A neurologist is a physician who specializes in disorders of the nervous system.
Neuropathy
Any and all disease or malfunction of the nerves.
Neurosurgeon (NS)
A physician trained in surgery of the nervous system and who specializes in surgery on the brain and other parts of the nervous system. Sometimes called a “brain surgeon.”
Nonsense Mutation
A truncated mutation. The protein is truncated by mutation, and so dysfunctional or non-existent depending on where the mutation occurs.
Nucleotides
Nucleotides are the chemical bases that make up DNA. The four chemical bases are adenine, thymine, cytosine, and guanine (usually referred to by the first letter of their chemical name: A, T, C, and G). These bases pair up with each other to form the rungs of the twisted-ladder-shaped DNA molecule.
Nystagmus
Nystagmus is a type of eye movement characterized by alternating smooth pursuit in one direction and saccadic movement in the other direction. Nystagmus may be: Physiologic nystagmus when occurring normally and serving its normal function. Pathologic nystagmus when occurring abnormally.

O

Ophthalmologist
An ophthalmologist is a physician who specializes in the medical and surgical care of the eyes and visual system and in the prevention of eye disease and injury.
Optic Chiasm
The area where the 2 optic nerves cross.
Optic Glioma
A benign tumor on an optic nerve or the optic chiasm.
Oscillopsia
Oscillopsia is a visual disturbance in which objects in the visual field appear to oscillate. The severity of the effect may range from a mild blurring to rapid and periodic jumping. Oscillopsia may be caused by loss of the vestibulo-ocular reflex, involuntary eye movements such as nystagmus, or impaired coordination in the visual cortex (especially due to toxins) and is one of the symptoms of superior canal dehiscence syndrome. Sufferers may experience dizziness and nausea. Oscillopsia can also be used as a quantitative test to document aminoglycoside toxicity.
Occupational Therapy (OT)
Otolaryngologist
A specialist in disorders of the ears, nose, throat, head and neck. Sometimes called an “ENT” – ear, nose and throat doctor.

Papilledema
Papilledema is optic disc swelling that is caused by increased intra cranial pressure. The swelling is usually bilateral and can occur over a period of hours to weeks. Papilledema occurs in approximately 50% of those with a brain tumor. As the optic nerve sheath is continuous with the sub arachnoid space of the brain (and is regarded as an extension of the central nervous system), increased pressure is transmitted through to the optic nerve and this leads to edema of the cells of the optic disc. Checking the eyes for signs of papilledema should be carried out whenever there is a clinical suspicion of raised intra cranial pressure. Because of the (rare) possibility of a brain tumor or pseudo tumor cerebri, both of which can increase intra cranial pressure, this examination has become common for patients suffering from headaches. The hallmarks of papilledema are: swelling of the optic disc poorly defined disc margins hemorrhage of disc nutrient vessels.
Partial Seizures
Partial seizures originate from a localized, or specific, part of the brain. There are two types of partial seizures: simple partial seizures, which do not alter an individual’s consciousness, and complex partial seizures, which may cause a sensation of dreaminess, dramatic mood change, or complete unresponsiveness.
Physical Therapy (PT)
Puralube
An over-the-counter ointment for dry eye treatment. This is similar to Lacrilube but it’s many crew members find it more economical.

R

Radiation Therapy
The use of ionizing radiation or radioactive substances to treat disease. Also known as actinotherapy; radiotherapy.
Radiologist
A radiologist is a medical professional who creates and interprets images, including x-rays, ultrasounds, MRIs, and CT scans. A neuroradiologist is trained to recognize abnormalities of the nervous system, including the brain findings associated with NF2.
Recreational Therapy (RT)

S

Seizure
A seizure is a sudden discharge of electrical activity in the brain that may cause a change in behavior, awareness, or sensation.
Sub occipital Approach
Visit: http://www.earsite.com/tumors/sa1.html for info.
Spontaneous Mutation
A spontaneous mutation is a mutation that is not inherited. Instead, the mutation occurs in the affected individual during the earliest stages of development, at or just after fertilization. Also known as a new, or sporadic, mutation.
Speech Therapy (ST)

T

Tegretol
Generic Name: carbamazepine (oral) (kar ba MAZ e peen) Brand Names: Carbatrol, Equetro, Tegretol, Tegretol XR What is Tegretol? Tegretol is in a group of drugs called anticonvulsants. It works by decreasing nerve impulses that cause seizures and pain. Tegretol is used to treat certain types of seizures associated with epilepsy, the treatment of the nerve pain associated with true trigeminal neuralgia and diabetic neuropathy. It is also used to treat bipolar disorder. Tegretol may also be used for other purposes not listed in this guide
Thyroplasty Implant
A procedure Designed to treat unilateral vocal cord paralysis.
Tinnitus
All hearing perception comes from patterns of electrical activity in neuronal networks in the auditory pathways. When these patterns originate in the cochlea as a result of sound stimulation, we hear our environment. When we detect spontaneous ‘compensatory’ activity generated within the pathways – that is tinnitus
Trigeminal Nerve
The fifth cranial nerve mainly responsible for facial sensation and the motor nerve controlling the muscles of mastication (chewing).
Trigeminal neuralgia (TN)
Trigeminal neuralgia (TN), or Tic Douloureux, (also known as prosopalgia) is a neuropathic disorder of the trigeminal nerve that causes episodes of intense pain in the eyes, lips, nose, scalp, forehead, and jaw.[1] It is estimated that 1 in 15,000 people suffer from trigeminal neuralgia, although those numbers may be significantly higher due to frequent misdiagnoses. TN usually develops after the age of 50, although there have been cases with patients being as young as three years of age [2]. The condition can bring about stabbing, mind-numbing, electric shock-like pain from just a finger\’s glance of the cheek. Believed to be the most severe type of pain known to humanity, the most common forms of TN affect 1 in 15,000 to 20,000, but 1 in 5,000 are thought to suffer from some type of facial pain.

V

Vagas Schwannoma
Introduction: Schwannomas are benign, encapsulated, solitary, slow-growing tumors which originate from nerve sheath cells in cranial, periferic, sympathetic nerve system. Approximately, 25–45% of schwannomas are in head and neck region. N. Vagus Schwannoma are seen relatively, rarely. The patients frequently apply with a slow-growing, painless cervical mass. Malign transformation is unusual.
Vestibular Schwannoma (VS)
Also known as Acoustic Neuroma
Vestibulocochlear Nerve
Eighth cranial nerve responsible for the sense of hearing. It is also pertinent to balance and body position sense.