Here is a list of terms used by the medical community. We have tried to offer it in layman's language. We all know how doctors love to use those technical names and phrases.

accessible - tumors which can be approached by a surgical procedure, not deep in the brain or beneath vital structures.

alopecia - loss of hair; baldness in areas where hair is usually present. A common side effect of radiation therapy to the brain and some chemical therapies.

anaplasia - characteristics of a cell identifies it as a cancer cell. Malignant.

angiogram - a diagnostic procedure done in the x-ray department to visualize blood vessels following introduction of a contrast material into an artery.

anosmia - absence of the sense of smell. Symptom common to tumors of the frontal lobe of the cerebral hemispheres.

aphasia - loss of ability to speak or write; loss of ability to understand speech or written words.

benign - not malignant.

biopsy - examination of a small amount of tissue taken from the patient's body to make a diagnosis.

cancer - malignant tissue that is invasive, destroys healthy tissue, and tends to spread to distant locations.

carcinoma - a malignant tumor that arises from epithelium, found in skin and the lining of body organs; for example, breast, prostate, lung, stomach or bowel. Carcinomas tend to infiltrate into adjacent tissue and spread (metastasize) to distant organs, such as bone, liver, lung, or the brain.

catheter - a flexible, tubular instrument, used for the removal or insertion of fluids.

cerebral - referring to the cerebrum, part of the brain.

cerebrospinal fluid - the clear fluid made in the ventricular cavities of the brain that bathes the brain and spinal cord.

cerebrum - the largest area of the brain, the cerebrum occupies the uppermost part of the skull. It consists of two halves called hemispheres. Each half of the cerebrum is further divided into four lobes: frontal, temporal, parietal and occipital.

chemotherapy - the use of chemical agents to treat brain tumors.

circumscribed - having a border, localized. Often associated with a capsule and benign tumors of the brain: meningiomas, pituitary adenomas and acoustic neuromas.

congenital - existing before or at birth.

contralateral - affecting the opposite side.

cranial cavity - the skull.

craniectomy - surgery performed on the skull where pieces of bone are removed to gain access to the brain, and the bone pieces are NOT replaced.

craniotomy - surgery performed on the skull where a portion of bone is removed to gain access to the brain, and the bone is PUT BACK in its place.

CT or CAT scan Computerized Axial Tomography - an x-ray device linked to a computer that produces an image of a predetermined cross-section of the brain. A special dye material may be injected into the patient's vein prior to the scan to help make any abnormal tissue more evident.

cyst - a fluid filled mass. Usually enclosed by a membrane.

debulk - a surgical procedure to decrease swelling by removing a portion of a tumor or dead tissue.

Decadron (R) - Dexamethasone. A glucocorticosteroid medication used to reduce brain tissue swelling.

decompressive - surgical procedure during which bone, tissue, or tumor is removed to lessen intracranial pressure.

diabetes insipidus - a problem with water balance in the body causing excess urine production and great thirst, due to pituitary-hypothalamic damage in the brain. Ordinary diabetes, which has the same symptoms, is due to insufficient insulin production by the pancreas.

diplopia - double vision.

distal - located far from the reference point.

dura mater - the outermost, toughest, and most fibrous of the three membranes (meninges) that cover the brain and spinal cord.

dysarthria - impairment of speech caused by damage or disorder of the tongue or speech muscles. Symptom may indicate pressure on the brain stem or elsewhere.

dysphagia - difficulty in swallowing or inability to swallow. Symptom usually indicates tumors involving the lower brain stem.

dysphasia - language disorder. Inability to speak words which one has in mind or to think of correct words; or inability to understand spoken or written words. Symptom common to tumors of the dominant cerebral hemisphere, particularly the frontal, temporal, and parietal lobes.

edema - swelling due to an excess of water.

encapsulated - tumor that is wholly confined to a specific area, surrounded by a capsule. Localized.

endoscope - a slender, tubular instrument used to examine the interior of a body cavity.

etiology - the study of the cause of a disease.

evoked potentials - the use of electrodes to measure the electrical activity of nerves. May be used as a guide during the removal of tumors growing around the important nerves.

extracerebral - located outside the cerebral hemispheres.

extradural - located outside the dura mater.

gait - pattern of walking.

ganglia - a mass of nerve tissue (gray matter) or a group of nerve cell bodies. Also refers to specific groups within the brain or spinal cord (as basal ganglia). Ganglion is the singular of ganglia.

glucocorticosteroids - medications used to decrease swelling around tumors.

gray matter - the "thinking brain" appears gray because it is composed of numerous nerve cells and blood vessels. The outer layer of the cerebrum - the cerebral cortex, and areas deep within the brain - the basal ganglia, are made up of gray matter.

growth factor - a naturally occurring protein chemical that stimulates cell division and proliferation. It is produced by normal cells during embryonic development, tisue growth, and wound healing. Tumors, however, produce large amounts of growth factors.

hemianopsia - loss of one half of the field of vision (the area that can be seen by each eye when staring straight ahead).

hemiparesis - muscle weakness of one side of the body.

hemiplegia - complete paralysis of one side of the body.

herniation - bulging of tissue through an opening in a membrane, muscle or bone.

heterogeneous - composed of various cell types.

homogeneous - composed of identical cell types.

hydrocephalus - Hydro = water, cephalo = head. Excess water in the brain due to blockage of cerebrospinal fluid flow, increased production, or decreased absorption.

hyperfractionation - an increased number of smaller dosage treatments of radiation.

hyperthermia - the use of heat to kill tumor cells.

hypophysis - pituitary gland.

hypotonicity - diminished muscle tone; limp muscles.

ICP -IntraCranial Pressure - harmful when increased.

immunotherapy - use of the body's immune system to fight tumors.

infiltrating - tumor that penetrates the normal, surrounding tissue.

informed consent - the right to have information explained to you so that you fully understand and agree to the nature of the proposed treatment.

interstitial radiation therapy - the implantation of radioactive seeds directly into a tumor.

intra-arterial - injection into an artery (that may supply a tumor).

intracerebral - located within the cerebral hemispheres (cerebrum).

intracranial - within the skull.

intradural - beneath the dura mater.

intramuscular - into a muscle.

intrathecal - injection into the sub-arachnoid space of the meninges. Usually done by lumbar puncture.

intratumoral - injection into a tumor (usually performed during surgery).

intravenous - injection into a vein.

intraventricular - injection into a ventricle.

invasive - refers to a tumor that invades healthy tissues. The opposite of encapsulated. Also called diffuse or infiltrating.

ipsilateral - affecting the same side.

irradiation - treatment by ionizing radiation, such as x-rays, or radioactive sources such as radioactive iodine seeds.

laser - an acronym of light amplification by stimulated emission of radiation. A surgical tool that creates intense heat and power when focused at close range, destroying cells by vaporizing them.

local - in the area of the tumor, confined to one specific area.

lumbar puncture - spinal tap. Needle penetration into the subarachnoid space of the lumbar spine. Used to withdraw a sample of spinal fluid for examination. Also used to inject a dye into the spine prior to a myelogram.

malignant - cancerous or life-threatening, tending to become progressively worse.

membrane - thin layer of tissue covering a surface, lining a body cavity, or dividing a space or organ.

metastisize - to spread to another part of the body, usually through the blood vessels, lymph channels, or spinal fluid.

monoclonal antibodies (MAB) - a biological response modifier with unique "homing device" properties. Chemicals or radiation tagged to the MAB may be delivered directly to tumor cells. Or, the MAB itself may be capable of tumor cell destruction.

MRI scan Magnetic Resonance Imaging - a scanning device that uses a magnetic field, radio waves, and a computer. Signals emitted by normal and diseased tissue during the scan are assembled into an image.

necrosis - dead cells. A common feature of glioblastoma multiforme and other malignant tumors, including metastatic cancer to the brain. Caused by either lack of blood supply or irradiation.

neoplasm - a tumor, either benign or malignant.

neuron - nerve cell; conducts electrical signals.

nervous system - the entire integrated system of nerve tissue in the body: the brain, brain stem, spinal cord, nerves and ganglia.

nuclear medicine - the branch of medicine that deals with the use of radioisotopes in therapy and diagnosis.

nucleus - the center of the cell containing the genetic information (genes, chromosomes, DNA, etc.) The appearance of the nucleus is used as a criterion to determine the malignant potential of a cell of tissue.

nystagmus - rapid movement of the eyeballs.

Ommaya reservoir - a device with a fluid reservoir implanted under the scalp with a catheter to a ventricle. It allows for medication to be given directly to the CSF (cerebrospinal fluid) and into the brain.

oncogene - fragments of genetic material (DNA) that carry the potential to cause cancer (transform normal cells into malignant cells).

oncogenesis - the causation or production of tumors.

palsy - complete paralysis.

papilledema - swelling of the optic nerve. Indicates increased intracranial pressure on the optic nerve. Also called choked disc.

paresis - weakness.

paresthesia - abnormal sensations, such as burning, prickling.

PET scan Positron Emission Tomography - a scanning device which uses low-dose radioactive sugar to measure brain activity. This is a limited-use diagnostic tool.

Phenobarbital (R) - a sedating medication used to control seizures.

photodynamic radiation therapy - a light sensitive drug which is given through a vein and concentrates in the tumor. Then, during a surgical procedure, a special light activates the drug. The activated drug kills the tumor cells.

PNET Primitive NeuroEctodermal Tumor.

primary brain tumor - original source of tumor which is the brain rather than other areas of the body.

primitive - undeveloped or in early stages of development, undifferentiated.

prognosis - a forecast as to probable outcome.

proto-oncogenes - fragments of genetic material (DNA), related to oncogenes, but are the normal "switches" used to control growth and tissue repair.

proximal - located closest to the reference point.

radiation therapy - the use of radiation energy to interfere with tumor growth.

radioresistant - resistant to radiation therapy.

radiosensitive - responsive to radiation therapy.

recurrence - the return of symptoms or the tumor itself, as opposed to a remission.

remission - the disappearance of symptoms; the disappearance of the tumor.

resection - surgical removal of a tumor.

residual - remaining tumor.

respiration - breathing. To inhale and exhale.

seizure - convulsions, epilepsy, due to temporary disruption in electrical activity of the brain.

shunt - a drainage system. Spinal fluid flows from a ventricle into a body cavity via a tube. Used to relieve increased intracranial pressure caused by brain tumors that block the flow of spinal fluid.

shunt (VA) ventriculo-atrial - the tube empties into the right atrium of the heart.

shunt (VP) ventriculo-peritoneal - the tube empties into the stomach.

spasticity - increased involuntary muscle contraction (the opposite of hypotonicity).

stalk - a stem. Usually refers to the pituitary stalk that connects the pituitary gland to the hypothalamus.

stereotactic - precise positioning in three dimensional space. Refers to surgery or radiation therapy directed by scanning devices.

stereotactic radiosurgery - a radiation therapy technique that uses a large number of narrow, precisely aimed, highly focused beams of ionizing radiation. The beams are aimed from many directions circling the head, and meet at a specific point, the tumor.

strabismus - imperfect eye coordination (crossed eyes).

subcutaneous - beneath the skin.

systemic - circulating throughout the body.

tinnitus - buzzing or ringing in the ear. Symptom common to tumors of the acoustic nerve.

tumor marker - substances found in blood or other fluids that identify the presence of a tumor, and/or the tumor type.

ultrasound - visualization of structures in the body by recording the reflections of sound waves directed into tissues. May be used during surgery.

vascular - relating to blood vessels.

vascularity - the blood supply of a tumor.

vertigo - dizziness. Symptom common to tumors of the acoustic nerve