Understand the words and terminology used for facial pain to become a more educated facial pain patient.

• Ablative removal, separation or cutting of a structure
• Acoustic neuroma (AN) a non-cancerous tumor growing on the acoustic or hearing nerve; occasionally AN can cause facial pain when it pushes a blood vessel onto the trigeminal nerve
• Adhesions fibrous growths similar to scar tissue that forms at the site of tissue damage
• Allodynia pain due to a stimulus which does not normally provoke pain
• Analgesics medications that relieve pain
• Anesthesia dolorosa painful numbness; occurs as unwanted side effect of some surgical TN treatments
• Anesthetic an agent used to abolish pain
• Anticonvulsant medication that prevents convulsions or seizures
• Aplastic anemia potentially fatal blood disorder caused by damage to bone marrow. Rare but potential side effect of some anticonvulsant medications.
• Arachnoid/arachnoiditis a membrane of the brain; when abnormally thickened, it is a potential cause of compression on the trigeminal nerve and is then termed arachnoiditis.
• Asymptomatic absence of symptoms
• Atlas the top-most bone of the spine
• Atropic wasted, smaller than usual
• Atypical irregular, not conforming to the type 
• Atypical trigeminal neuralgia (ATN) a type of facial pain that may have some of the characteristics of classic TN (sharp stabs and trigger points) plus other symptoms (i.e. constant, aching or burning pain in addition to the stabs); sometimes referred to as TN2
• Axon process of a nerve cell by which impulses travel away from the cell body
• Auditory related to hearing
• Bilateral referring to both sides; bilateral facial pain occurs on both sides of the face
• Cerebellum part of the brain that controls movements
• Cerebral cortex part of the brain that analyzes nerve signals and sends out responses
• Cerebrospinal fluid (CSF) a fluid composed mostly of water, glucose, salt and proteins that surrounds, cushions and provides nutrients to the brain and spinal cord; a CSF leak occurs when CSF escapes through a small tear or hole in the outermost layer of connective tissue (called the dura mater) that surrounds the brain and spinal cord and holds in the CSF. This is an uncommon risk of MVD and other surgeries of the head.
• Cluster headache searing, boring, come-and-go pain in the face or forehead thought to be caused by dilation of the blood vessels in the skull; sometimes confused with trigeminal neuralgia
• Cluster tic syndrome combination of cluster headaches and trigeminal neuralgia
• Compounding a pharmacy technique in which medications are custom-prepared to meet specific needs of individual customers; those who offer this service are called “compounding pharmacists”
• Computer tomography CT sophisticated X-ray which takes pictures of layes of the body at any depth. 
• Cranial nerves twelve pairs of nerves that serve various areas and functions of the head; the trigeminal (facial) nerve is one of these
• Craniectomy surgical opening of the skull necessary for brain surgery
• Craniosacral therapy gentle manipulation technique somewhat similar to light massage that is aimed at freeing the flow of cerebrospinal fluid; some believe impeded flow of this fluid can cause face pain
• Deafferentation pain pain that occurs when parts of a nerve are injured to the point where they are disabled; usually a constant, burning type of pain
• Deep brain stimulation A procedure in which surgeons insert a thin electrode through a small opening in the skull into the thalamus, a part of the brain where pain sensation occurs. A stimulation device attached to the electrode delivers low-grade electrical signals in an attempt to override pain signals.
• Demyelination the process of losing or destroying myelin, the protective sheath around nerve fibers
• Diagnostic distinctive feature of a disease
• Dura. The waterproof covering that surrounds the brain.
• DREZ acronym for “dorsal root entry zone,” a surgical procedure done in the neck region to disable the origin of the trigeminal nerve in the upper spine
• Dysesthesia numbness or abnormal sensation severe enough that a it may be disturbing
• Endodontist a dentist who specializes in filling root canals of teeth 
• Endoscope a surgical instrument that uses a tiny camera to project brightened and magnified images from inside the body
• Epidemiology the study of disease as it occurs in groups of people or even other populations
• Ephaptic transmission conduction across nerves at sites where it should not normally occur.
• Facial nerve cranial nerve that controls most of the muscles and sensation in the face and some of the muscles that control chewing
• Facial palsy weakness of the muscles of facial expression
• Gamma Knife a non-incision surgical device that uses gamma radiation to cause precisely aimed damage to targeted tissue; used to create lesions on the root of the trigeminal nerve to lessen pain
• Ganglion a cluster of nerve cells
• Gangliolysis a surgery to create targeted damage to a ganglion, usually to stop pain signals from getting to the brain
• Gasserian ganglion the cluster of nerve cells where the trigeminal nerve branches out into its three divisions and exits the skull
• Gate Control a theory to explain how pain is experienced
• Glial cells type of cells that the body uses to build myelin, the insulating sheath around nerves
• Glossopharyngeal neuralgia pain that is in the throat and neck;  involving the glossopharyngeal nerve
• Glycerol an oily alcohol substance that damages nerve fibers when in direct contact with the fibers
• Granulomas abnormal growths as a result of irritation
• Hematoma a bruise
• Herpes zoster also known as shingles, this is a viral infection caused by the same virus that causes chickenpox; can cause burning pain on the face and/or body
• Hypesthesia medical term for numbness
• Hyperalgesia an increased response to a stimulus which is normally painful
• Idiopathic refers to a disease or condition of unknown cause or origin
• Lesion an area of tissue damage
• Linac acronym for linear accelerator, a non-incision surgical device that uses high-energy X-rays to cause precisely aimed damage to targeted
• Lumbar puncture insertion of a needle into the back to tap out CSF for testing
• Mandibular area referring to the lower jaw region of the face
• Masseter  a muscle which runs through the rear part of the cheek from the temporal bone to the lower jaw on each side and closes the jaw in chewing
• Maxillary area referring of the upper jaw and cheek region of the face
• Meckel’s cave cavity made up of dura mater (brain lining material) in which sits  the trigeminal ganglion and the divisions of the trigeminal nerve it is located inside the skull
• Meningioma tumor of the meninges, the membrane that covers the brain and spinal cord; can cause facial pain if the tumor pushes a blood vessel against the trigeminal nerve
• Microvascular decompression (MVD) type of brain surgery in which the aim is to lift a compressing blood vessel off the trigeminal nerve and insulate the two with a small cushion
• Motor cortex stimulation surgical procedure in which one or two small contact plates attached to an electrical stimulation device are placed on the surface of the brain over the cortex region; stimulating this region with low-grade electrical current reduces activity in the thalamus where pain is felt
• Myelin the protective coating that surrounds nerve fibers; made out a layer of proteins packed between two layers of lipids (fats)
• Myofascial pain dull, aching muscle pain of uncertain cause; when it occurs in the facial muscles, the pain can be triggered by touching the area
• Nerve block use of a drug, chemical or surgery to stop a nerve signal from getting through to the brain; can be used for temporary pain relief or as a way to diagnose the exact nature and location of a pain
• Nerve fiber strand of tissue made up of nerve cells that carries nerve impulses (biochemical signals to and from the brain)
• Nervus intermedius a branch of the genicular nerve; when compressed by a blood vessel, it can cause pain deep in the ear
• Neurectomy surgical removal of a nerve or nerve branch
• Neuropathic pain originates in the nerve, usually due to injury or disease
• Neuropathy disturbance of function or pathological change in a nerve causing numbness when it occurs in a sensory nerve
• Neurotransmitter body chemical that is used to transmit nerve impulses from one nerve cell to another; sodium and calcium are two of the most common
• NICO acronym for neuralgia-inducing cavitational osteonecrosis; presumed cause is a chronic infection of bone in the jaw that can damage the nerve branches in the affected bone
• Nociceptor type of nerve receptor that activate when there is a painful stimulus
• Ophthalmic area referring to the region of the face around the eyes
• Opioids pain-killing agents that originate from the poppy flower and its product, opium
• Orofacial area of the face around the mouth
• Palsy a medical term which refers to various types of paralysis, often accompanied by weakness and the loss of feeling and uncontrolled body movements
• Pain threshold the point at which an applied, escalating sensory stimulus (heat, cold, pressure, pin-prick, etc.) is reported by a person as pain
• Pain tolerance the reaction of a person to reported pain after it has crossed the pain threshold
• Paratrigeminal neuralgia throbbing headache-like pain in the upper branch of the trigeminal nerve, thought to be caused either by an inflammation or infection of the nerve; also called “Raeder’s syndrome”
• Paresthesia an unusual sensation that may be described as “tingling,” “crawling” or pins and needles; often accompanies mild numbness; an abnormal sensation whether spontaneous or evoked
• Percutaneous through the skin; when referring to “percutaneous procedures” in treating facial pain, a type of surgery in which the surgeon inserts a needle or electrode through the cheek as opposed to entering the skull
• Peripheral nerves nerves outside the brain and spinal cord; these include the many branches of the trigeminal nerve that serve the teeth, gums and other parts of the face
• Post-herpetic neuralgia a type of facial pain caused by damage from the herpes zoster (chicken-pox) virus; may occur after a bout of shingles
• Preganglionic situated proximal to the a ganglion
• Radiofrequency use of generated heat through an electrode to cause selected damage to tissue 
• Radiosurgery the use of radiation devices to treat diseases and disorders without having to cut into tissue; examples are Gamma Knife and CyberKnife
• Refractory stubborn or unmanageable; resistant to a process or treatment
• Remyelination the process of rebuilding lost or damaged myelin, the protective sheath around nerve fibers
• Root entry zone section of the trigeminal nerve near the brainstem at which point the myelin covering changes
• Rhizotomy surgery to cut or damage a nerve root so as to interfere with the transmission of pain signals to the brain
• Stereotactic guided by X-ray view or similar scanning device; a way for surgeons to be guided to precise, three-dimensional locations in the skull and face
• SUNCT acronym for “short-lasting, unilateral, neuralgiform headaches with conjunctival injection and tearing”; a sharp, come-and-go pain centering around the eye along with a red eye, tearing and a runny nose; believed to be caused by an inflammation of blood vessels around the eye
• Secondary trigeminal neuralgia facial pain that occurs as a result of another condition, such as multiple sclerosis or a tumor
• Temporal arteritis aching, throbbing and sometimes burning pain in the temple area caused by an inflamed artery in that area
• TENS unit a device that delivers regular, low-grade electrical signals that distract or override pain signals; TENS is an acronym for transcutaneous electrical stimulation
• Thermocoagulation using heat to create tissue injury; the technique used in radiofrequency lesioning surgery
• Thalamus the part of the brain that relays messages between various parts of the body and the appropriate other part of the brain; the brain’s “central switching station”
• Tic douloureux “painful spasm” in French; another name for trigeminal neuralgia
• TMJ disorder/TMD pain in the jaw joint 
• Trigeminal neuritis an inflammation of the trigeminal nerve and/or its branches
• Trigeminal nucleus the origin of the trigeminal nerve in the top three bones of the spinal column, the upper-cervical spine
• Trigger point often at the end of a nerve which if touched results in pain; also referred to as the action that sets of facial pain, such as tooth-brushing, cold air, or chewing