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Term Definition
 
ABIsee Auditory Brainstem Implant
 
ABRsee Auditory Brainstem Response
 
Acoustic NeuromaA benign tumor developing on the hearing and balance nerves near the inner ear.
 
ANsee Acoustic Neuroma
 
Artifical TearsEye 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.
 
AstrocytomaA tumor that begins in the brain or spinal cord in small, star-shaped cells called astrocytes.
 
AsymptomaticAsymptomatic means showing or causing no obvious symptoms.
 
Auditory Brainstem ImplantA 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 ResponseA 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.
 
Autosomal DominantAutosomal 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.
 
Benign TumorA 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.
 
BTBrain Tumor
 
Cavernous SinousA 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.
 
cerebellumThe 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 edemaIt is an excess accumulation of water in the intracellular and or extracellular spaces of the brain.
 
cerebral spinal fluidIs 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 inta-cerebral(inside the brain, cerebrum) ventricles, cistems and sulsi( singular sulcus) as well as the central canal of the spinal cord.
 
Cerebrospinal fluidCerebrospinal fluid (CSF), Liquor cerebrospinalis, is a clear bodily fluid that occupies the subarachnoid space and the ventricular system around and inside 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, cisterns and sulci (singular sulcus), as well as the central canal of the spinal cord. It is an approximately isotonic solution and acts as a \"cushion\" or buffer for the cortex, providing also a basic mechanical and immunological protection to the brain inside the skull.
 
Chromosome 22The chromosome containing the faulty gene which causes NF2.
 
ChromosomesChromosomes 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.
 
CIsee Cochlear Implant
 
CINE MRICine 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
 
Cochlear ImplantA 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.
 
Computed Tomography (CT)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.
 
CongenitalCongenital refers to a condition that is present at birth.
 
craniotomyA 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 stimulators 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.
 
Crocodile Tears Unintentional big tears that seem like you are crying. Can be caused by eating or extremely Dry Eye.
 
CystA cyst is a closed sac of air, fluid or semisolid material.
 
DebulkingDebulking is the surgical removal of part of a malignant tumour 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.
 
DexamethasoneDexamethasone 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 hydrocortisone 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 intracranial hypertension (pseudotumor cerebri), altitude sickness, cystinuria, and dural ectasia. Acetazolamide is available as a generic drug and is also used as a diuretic.
 
Diploid NeoplasmA 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.
 
Electrocardiogram (ECG, EKG)An electrocardiogram is a noninvasive procedure that measures the heart's electrical activity.
 
ElectrocochleographyElectrocochleography: 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.
 
ElectromyogramA 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.
 
Electrophysiological monitoring for seleSelective shunt during carotid endarterectomy is more and more widespread, but it requires a monitoring system able to identify severe brain ischemia correctly. In 255 endarterectomies for severe carotid stenosis, we evaluated cerebral activity by means of sequential use of computerized two-channel electroencephalogram (EEG) and somatosensory evoked potentials (SSEPs). In 1.96% of cases, we observed changes referable to severe cerebral ischemia: in one case, in spite of shunting, EEG asymmetry persisted till the end of the operation, and the patient awoke with irreversible aphasia. In two other cases, a progressive disappearance of the cortical wave (N20) occurred in spite of a normal EEG pattern. None of the unshunted patients had postoperative deficit. Computerized EEG is an easily interpretable method of monitoring and reveals rapidly developing cerebral ischemia, but severe SSEP changes can occur in spite of a normal EEG pattern when cerebral ischemia has a slow onset. Although SSEP monitoring is a slower method of recording, it can give a finer distinction of less severe cerebral ischemia.
 
EMGsee Electromyogram
 
EncephalomalaciaA 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.
 
ENTEar, Nose & Throat Doctor
 
EpendymomaA 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.
 
Facial nerve paralysisFacial 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 jugulare tumor 1. Both cases invaded the adjacent cerebellopontine angle, leading to cochleo-vestibular deficits prior to the operation. After surgery, recovery of the audiovestibular function, including hearing, auditory brainstem response and caloric response, was anticipated in both patients. Therefore, cochleo-vestibular deficits in JF tumors can be attributed to compression neuropathy, rather than tumor infiltration.
 
FibromygaliaA syndrome characterized by chronic pain, stiffness, and tenderness of muscles, tendons, and joints without detectable inflammation.
 
Fractionalized Stereotactic RadiosurgeryStereotactic 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.
 
FSRsee Fractionalized Stereotactic Radiosurgery
 
Gamma Knife.A type of highly focused radiation therapy.
 
GeneA 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 CounselorA genetic counselor is a healthcare 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 DisorderA 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.
 
GeneticistA geneticist is a medical doctor who specializes in the diagnosis and care of individuals with genetic disorders.
 
Germ LineGerm line refers to the body's reproductive cells, either the egg or the sperm.
 
Glial CellA 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.
 
HEIsee House Ear Institute
 
House Ear InstituteLocated in Los Angeles, California, USA They are the original developers of the Auditory Brainstem Implant and have tremendous experience both removing Acoustic Neuromas and placing the Implant.
 
HydrocephalusHydrocephalus is a buildup of spinal fluid in the ventricles of the brain, causing intracranial pressure.
 
Intensity-modulated radiation therapyIntensity-modulated radiation therapy (IMRT), an exciting recent development in the field of radiation therapy, is widely anticipated by many to make possible significant improvements in the quality of radiation treatments delivered to patients. The NOMOS Peacock method of delivery, often referred to as serial tomotherapy because of its \"slice-wise\" treatment of a tumor, has been used since 1994 to treat some 8000+ patients worldwide. This slice-wise method of treatment is known to produce extremely conformal dose distributions due to its ability to specifically match the dose distribution on each slice to the shape of the target volume on that same slice. Based on the belief of this institution, and the NOMOS Corporation, that an increase in the number of treatment slices into which the target is segmented would lead directly to an improvement in three-dimensional (3D) dose conformality, a joint effort was undertaken to develop a new MIMIC collimator treatment mode. Inherent to the original design of the NOMOS MIMIC binary multileaf collimator were 2 treatment modes: a 2-cm mode with a slice thickness of approximately 1.7 cm and a 1-cm mode with a slice thickness of approximately 0.85 cm. As a result of this collaborative effort, a new MIMIC treatment mode has been developed. The method employs a slit collimator, post-collimation device known as the BEAK, enabling the treatment mode referred to as Beak Mode. The device imposes a distal redefinition of the slice thickness, or length, by effectively blocking the full retraction of the MIMIC vanes. The end result is a newly available slice thickness of approximately 4 mm, which is shown in this work to yield significant improvements in dose conformality for 2 representative patients. The comparative analysis of these 2 patient plans includes, in addition to a comparison of isodose distributions, an evaluation of dose-volume histogram (DVH) information, and a comparison of indices of conformality (CI) and homogeneity (HI). Summary The retrosigmoid approach continues to be the most widely employed strategy for the surgical resection of acoustic neuromas. The results with respect to facial nerve function are uniformly reported to be quite high. The great emphasis currently is upon improving results with regard to the conservation of useful hearing. This paper focuses on the anatomical and strategic surgical factors that we currently consider to be important to maximizing our current results. The future aspects of this trend toward improved success in conserving hearing in these patients is also discussed.
 
LacrilubeAn over-the-counter ointment for dry eye treatment. A.K.A. "Night Goop".
 
LaminectomyLaminectomy 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.
 
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 Cavea 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.
 
MeningiomaA common type of slow growing, usually benign brain tumor that arises from the protective covering of the brain and spinal cord.
 
MicromoleA 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 ApproachA surgical approach for Acoustic Neuromas where an incision is made in the scalp above the ear.
 
MRIsee Magnetic Resonance Imaging
 
MutationA mutation is a permanent change in DNA. Mutations can be inherited or can occur spontaneously.
 
neuro-ophthalmologistA neuro-ophthalmologist is a physician (neurologist or ophthalmologist) specializing in diseases affecting vision that originate from the nervous system.
 
NeurofibromatosisNeurofibromatosis 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.
 
NeurologistA neurologist is a physician who specializes in disorders of the nervous system.
 
NeuropathyAny and all disease or malfunction of the nerves.
 
NeurosurgeonA 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."
 
NF2Abbreviation for neurofibromatosis type 2
 
Nonsense MutationA truncated mutation....the protein is truncated by mutation, and so dysfunctional or non-existent depending on where the mutation occurs.
 
NSsee NeuroSurgeon
 
NucleotidesNucleotides 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.
 
NystagmusNystagmus 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
 
OphthalmologistAn 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 ChiasmThe area where the 2 optic nerves cross.
 
Optic GliomaA benign tumor on an optic nerve or the optic chiasm.
 
OscillopsiaOscillopsia 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.
 
OTOccupational Therapy (Therapist)
 
OtolaryngologistA 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 intracranial 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 tumour. As the optic nerve sheath is continuous with the subarachnoid 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 intracranial pressure. Because of the (rare) possibility of a brain tumor or pseudotumor cerebri, both of which can increase intracranial 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 SeizuresPartial 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.
 
PTPhysical Therapy (Therapist)
 
PuralubeAn over-the-counter ointment for dry eye treatment. This is similar to Lacrilube but it's many crew members find it more economical.
 
Radiation Therapy(medicine) The use of ionizing radiation or radioactive substances to treat disease. Also known as actinotherapy; radiotherapy.
 
RadiologistA 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.
 
RTRecreational Therapy (Therapist)
 
SeizureA seizure is a sudden discharge of electrical activity in the brain that may cause a change in behavior, awareness, or sensation.
 
SonicationSonication is the act of applying sound (usually ultrasound) energy to agitate particles in a sample, for various purposes. In the laboratory, it is usually applied using an ultrasonic bath or an ultrasonic probe, colloquially known as a sonicator. In a paper machine, an ultrasonic foil can distribute cellulose fibres more uniformly and strengthen the paper. Sonication can be used to speed dissolution, by breaking intermolecular interactions. It is especially useful when it is not possible to stir the sample, as with NMR tubes. It may also be used to provide the energy for certain chemical reactions to proceed. Sonication can be used to remove dissolved gases from liquids (degassing) by sonicating the liquid while it is under a vacuum. This is an alternative to the freeze-pump-thaw and sparging methods. In biological applications, sonication may be sufficient to disrupt or deactivate a biological material. For example, sonication is often used to disrupt cell membranes and release cellular contents. Sonication can also loosen particles adhering to the wall of a vessel. Therefore it can be used as a cleaning step, easier than scraping them off with a spatula. Outside the field of laboratory science, sonicating baths are used to clean objects such as spectacles and jewelry. Sonication is also used to extract microfossils from rock.[1] Sonication can also refer to buzz pollination - the process that bees use to shake pollen from flowers by vibrating their wing muscles Suboccipital Approach: click on the link http://www.earsite.com/tumors/sa1.html
 
Spontaneous MutationA 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.
 
STSpeech Therapy (Therapist)
 
TegretolTegretol 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.
 
tinnitusAll 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 NerveSee V Cranial Nerve
 
Trigeminal neuralgiaTrigeminal 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 misdiagnosis. 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 Cranial NerveFunctions both as the chief nerve of sensation for the face and the motor nerve controlling the muscles of mastication (chewing), also known as the trigeminal nerve
 
Vagas SchwannomaVagas Schwannoma ~Introduction: Schwannomas are benign, encapsulated, solitary, slow-growing tumors which originate from nerve sheath cells in cranial, periferic, symphathetic nerve system. Aproximately, 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 servical mass. Malign transformation is unusual.
 
Vestibular Schwannomasee Acoustic Neuroma
 
Vestibulocochlear Nervesee VIII Cranial Nerve
 
VIII Cranial NerveResponsible for the sense of hearing. It is also pertinent to balance and body position sense .
 


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