MicroVentionTerumo

Clinical Education

MicroVention participates in global clinical studies in order to establish the safety and efficacy of the products we develop, sell and license. Research provides real world data and experience that drives the adoption of emerging technologies. Please see below for information on our ongoing and completed clinical trials.

  • a benign tumor of the hearing nerve (eighth cranial nerve).

  • a benign growth formed of glandular tissue.

  • the outermost lining of a blood vessel, composed primarily of connective tissue and elastic fibers; provides elastic and structural strength to the artery.

  • loss of ability to recognize objects, people, sounds, shapes or smells. Usually classified according to the sense or senses affected. Symptom common to damage to parietal lobes of cerebral hemispheres

  • a connection between two vessels or tubes such as arteries.

  • a thin-walled outpouching or dilation of a blood vessel.

  • also referred to as arteriogram; a radiographic technique used for visualization of the blood vessels using standard radiographic methods in conjunction with the intra-arterial injection of iodinated contrast medium.

  • radiography of blood vessels using the injection of contrast material (dye) to better visualize the vessels. Derived from angio (blood vessels) and gram (record or picture). (see also Intra-arterial catheterization angiography)

  • reconstitution or recanalization of a blood vessel; may involve balloon dilation, mechanical stripping of intima (innermost layer of an artery), forceful injection of a thrombolytic (clot-busting) agent, or placement of a stent (vessel prosthesis).

  • the tough outer ring of a spinal disk.

  • medications that prevent or slow blood coagulation.

  • medications that prevent or slow aggregation of platelets, a critical step in the blood clotting process.

  • loss of ability to speak or write; loss of ability to understand speech or written words not related to intelligence but to specific lesions in the brain.

  • the ability of the stent to sufficiently expand so that its struts press against the vessel wall.

  • inability to perform purposeful movements.

  • the thin, delicate membrane interposed between the dura mater and the pia mater of the entire brain and with them constituting the brain meninges – a protective covering of the brain made up of delicate, elastic tissues and blood vessels.

  • inflammation of the arachnoid membrane, most commonly seen within the spinal cord around the spinal cord and cauda equina.

  • irregular heartbeat.

  • over a period of weeks to months after ballooning, an active remodeling occurs that reduces arterial size. Stenting inhibits negative arterial remodeling.

  • over a period of time after stenting, an active remodeling can occur which increases lumen diameter size.

  • thickening and calcification of the arterial wall with loss of elasticity and contractility.

  • relating to both arteries and veins.

  • an abnormal, direct passageway between an artery and a vein.

  • an abnormal collection of blood vessels in which blood flows directly from arteries to veins without an intervening capillary bed.

  • a tumor within the substance of the brain or spinal cord made up of astrocytes – often classified from Grade I (slow-growing) to Grade III (rapid growing).

  • lack of coordination in bodily movements.

  • arterial disorder characterized by thickening, loss of elasticity and calcification of arterial walls resulting in decreased blood supply.

  • unit of measurement of pressure used to inflate a balloon.

  • a “wasting away”; a diminution in the size of a cell, tissue, organ or part.

  • the outer diameter of the balloon catheter at a specific location. The four profiles commonly used include: tip entry, crossing, mid balloon, and proximal balloon.

  • the tapered portions of the balloon. This length is not included in the labeled balloon length.

  • a stent that is mounted on a balloon and is deployed by expanding the balloon.

  • not malignant, not recurrent, favorable for recovery.

  • a network of nerves in the neck, passing under the collarbone and into the the/omit armpit. These nerves originate from the 5th, 6th, 7th and 8th cervical spinal nerves and the first 2 thoracic spinal nerves.

  • slowness in movement.

  • the stemlike portion of the brain connecting the cerebral hemispheres with the spinal cord, and comprising the pons, medulla, oblongata, and midbrain; considered by some to include the diencephalon.

  • the loss of sensation of touch, position sense, and movement on the side of a spinal cord lesion, with loss of pain sensation on the other side. Caused by a lesion limited to one side of the spinal cord.

  • an abnormal sound or murmur heard while auscultating (listening to) an organ or body.

  • one of the minute vessels connecting the arterioles and venules, the walls of which act as a semipermeable membrane for interchange of various substances between the blood and tissue fluid.

  • cancer, a malignant growth of epithelial or gland cells.

  • the large artery on either side of the neck that supplies most of the cerebral hemisphere.

  • an abnormal communication between the internal and external portions of the carotid arteries or any of their branches and the cavernous sinus.

  • slight dilatation on the common carotid artery at its bifurcation containing nerve cells sensitive to blood pressure. Stimulation can cause slowing of the heart, vasodilatation and a fall in blood pressure.

  • the cavernous portion of the internal carotid artery is an “S-shape” portion of the vessel that travels through the cavernous sinus (which is a venous room) and then exits the cavernous sinus as the supraclinoid portion of the ICA.

  • a hollow, flexible tube for insertion into a body cavity, duct, or vessel. Used in the endovascular treatment of cerebral aneurysms.

  • the bundle of long spinal nerve roots arising from the end of the spinal cord and filling the lower part of the spinal canal (from approximately the thoracolumbar junction down). These long nerves resemble a horse's tail (cauda equina).

  • toward the distal end of the spine.

  • the brain and the spinal cord.

  • the part of the brain situated on the back of the brainstem, to which it is attached by three cerebellar peduncles on each side; it consists of a median lobe and two lateral lobes.

  • a weak bulging spot on the wall of a brain artery; also called a brain or intracranial aneurysm.

  • a clear, water-like fluid that circulates around the brain and spinal cord.

  • the main portion of the brain, occupying the upper part of the cranial cavity; its two hemispheres, united by the corpus callosum, form the largest part of the central nervous system in humans.

  • upper spine, neck. Made up of seven vertebrae.

  • the downward (caudal) displacement of part of the cerebellum or brainstem below the foramen magnum. May also have/cause hydrocephalus, cord symptoms.

  • a disorder, usually of childhood, characterized by irregular, spasmodic involuntary movements of the limbs or facial muscles.

  • a vascular structure in the ventricles of the brain that produces cerebrospinal fluid.

  • allows blood that enters by either internal carotid (anterior circulation) or vertebral arteries (posterior circulation) to be distributed to any part of both cerebral hemispheres. Allows communication between anterior and posterior circulation.

  • one type of alloy used to make balloon-expandable stents. Very thin and flexible material.

  • a state of profound unconsciousness from which one cannot be roused.

  • the ability of a balloon material to increase in size or stretch as the pressure is increased; it is determined by the balloon’s diameter growth over a range of inflation pressure.

  • type of balloon material with the highest rate of diameter growth per ATM of pressure.

  • a diagnostic imaging technique that rapidly x-rays the body in cross-sections, or slices. A computer pieces together the x-rays to create a three- dimensional map of soft tissue or bone.

  • a disruption, usually temporary, of neurological function resulting from a blow or violent shaking.

  • a confidence interval gives you the range of values that fall within a given degree of certainty. A 95% confidence interval tells us that we can be fairly (95%) certain that the true value will fall within this range.

  • the flexibility of the stent to conform to the vessel. Flexibility refers to the stent system as a whole.

  • present at and existing from the time of birth.

  • stroke in the opposite hemisphere of the lesion.

  • a radiopaque material used to visualize arteries and veins in an angiogram.

  • the line of junction of the frontal bones and the parietal bones of the skull.

  • removal of the body of a vertebra. The body is the solid bony mass, almost circular in appearance that forms the front part of each vertebra.

  • the fibrous band connecting the hemispheres of the brain.

  • the external layer of gray matter covering the hemispheres of the cerebrum and cerebellum.

  • trade name for the anticoagulant Warfarin Sodium.

  • surgical removal of a portion of the skull.

  • a congenital tumor arising from the embryonic duct between the brain and pharynx.

  • the operative repair of a defect of the skull.

  • premature closure of cranial sutures, limiting or distorting the growth of the skull.

  • surgical procedure where a section of the skull cap is temporarily removed.

  • the part of the skull that holds the brain.

  • ability to cross or recross through a lesion, an already deployed stent, or any area of resistance in the vessel.

  • combines IV injection of contrast with CT scan.

  • a position in which the arms are extended and internally rotated and the legs are extended with the feet in forced plantar flexion. This condition usually indicates compression of the brainstem.

  • a position in which the upper extremities are rigidly flexed at the elbows and wrists. This indicates a lesion in the mesencephalic region of the brain.

  • the general term physicians use to indicate the overall ease with which a stent system can be “delivered” to the lesion site.

  • subtraction of bony images from an angiographic image to allow clearer visualization of opacified vessels.

  • the radial force exerted by the balloon on the lesion or metal stent. It is a function of inflation pressure and balloon material (compliance). Note that a more compliant balloon material results in reduced dilation force at the lesion.

  • Dilantin; a medication used to control seizures.

  • double vision, due usually to weakness or paralysis of one or more of the extra-ocular muscles.

  • an off-label method of stent placement, such that the stent is placed across the lesion without pre-dilation. Also referred to as “primary stenting.”

  • the round balloon-like portion of an aneurysm which usually arises from the artery from a smaller portion called the neck of the aneurysm.

  • a non-invasive study that uses sound waves to show the flow in a blood vessel and can be used to determine the degree of narrowing (percent stenosis) of the vessel. A wand is placed on the skin over the vessel to be imaged. This study has no risks and is not painful.

  • a type of stent that has been coated with a drug to inhibit neointimal formation, a known biological response to ballooning and stenting in the vasculature.

  • the outermost, toughest, of the three meninges (membranes) of the brain and spinal cord; a protective covering for the brain.

  • impairment of speech caused by damage or impairment of the tongue speech muscles. Symptom may indicate pressure on the brainstem or elsewhere in the posterior fossa.

  • a condition in which a disagreeable sensation is produced by ordinary touch, temperature or movement.

  • difficulty swallowing.

  • Inability to speak words which one has in mind or to think of correct words. Inability to understand spoken or written words.

  • abnormality in development of a tissue or organ.

  • difficulty breathing.

  • a group of movement disorders that vary in their symptoms, causes, progression, and treatments. This group of neurological conditions is generally characterized by involuntary muscle contractions that force the body into abnormal, sometimes painful, movements and positions (postures).

  • swelling due to an excess of water.

  • the study of the electrical currents set up by brain actions; the record made is called an electroencephalogram.

  • when a developing thrombus dislodges from the source and travels downstream to cause an occlusion elsewhere in the cerebral vasculature.

  • a technique, also referred to as coiling, that seals off the cerebral aneurysm and stops further blood from entering into the aneurysm. This treatment is done endovascularly.

  • a foreign object, quantity of gas, a bit of tissue or thrombus that circulates in the bloodstream until lodging in a vessel.

  • the herniation of brain meninges through a skull defect.

  • the removal of fatty or cholesterol plaques and calcified deposits from the internal wall of an artery.

  • a thin, telescope-like instrument. A video camera attached to the endoscope records images a surgeon can view on a monitor. Specially designed surgical tools enable a surgeon to operate through small incision(s).

  • the layer of epithelial cells that lines the cavities of the heart and of the blood and lymph vessels, and the serous cavities of the body.

  • within the vascular system.

  • the membrane that lines the cerebral ventricles of the brain and central canal of the spinal cord.

  • a growth in the brain or spinal cord arising from ependymal tissue.

  • the study of the distribution of disease and its impact upon a population using measures such as incidence, prevalence and mortality.

  • immediately outside the dura mater. Same as extradural.

  • a blood clot between the dura mater and the inside of the skull.

  • disorder characterized by abnormal electrical discharges in the brain, causing abnormal sensation, movement, or level of consciousness.

  • the study of cause of disease.

  • a thin, elastic layer between the media and adventitia of an artery. Not present in intracranial arteries.

  • outside the cranial cavity.

  • the buildup of plaque on the inside walls of arteries in the extracranial vessel, thus obstructing the circulation.

  • a small, smooth-surfaced end of a bony projection (articular process) that functions as part of a joint.

  • each of four joints formed above and below and on either side of a vertebra. The lower bony projection of one vertebra meets the upper projections of the vertebra below it, forming facet joints.

  • surgical removal of one of the facets; excision of a facet joint.

  • an extension of dura between the right and left hemispheres of the brain.

  • the dissolution of fibrin by enzymatic action.

  • drug that breaks up fibrin (clot); used for stroke therapy (eg: tPa, urokinase).

  • smooth muscle cells covering plaque.

  • an examination by means of the fluoroscope to visually observe the form and motion of blood vessels by means of x-ray shadows projected on a fluorescent screen.

  • normal openings in the skull of infants; the largest of these is the anterior fontanel or "soft spot" in the middle of the head.

  • a hole or opening that acts as a passageway for nerves or blood vessels.

  • surgical enlargement of the foramen/foramina.

  • the amount of longitudinal shortening that the stent experiences upon expansion after deployment.

  • a sausage-like enlargement of the blood vessel.

  • equipment that precisely delivers a concentrated dose of radiation to a predetermined target using gamma rays.

  • the most widely used system of classifying the severity of head injuries or other neurologic diseases.

  • an evaluation scale based on individual overall social capability (or dependence) of patients. It takes into account the combined effects of specific mental and neurological deficits.

  • the major support cells of the brain. These cells are involved in the nutrition and maintenance of the nerve cells.

  • a rapidly growing tumor composed of primitive glial cells, mainly arising from astrocytes.

  • a tumor formed by glial cells.

  • part of the basal ganglia which are brain cells that lie deep in the brain.

  • a branch of the second cervical spinal nerve that innervates the middle portion of the occipital area (at the back of the skull) of the scalp.

  • in the endovascular treatment of cerebral aneurysms, these flexible tubes are introduced into the patient’s carotid artery in the neck to function as a working channel through which devices, like microcatheters, may be introduced into the brain.

  • a thin, usually flexible wire that can be inserted into a confined or tortuous space to guide and facilitate passage of instrumentation, such as a catheter. Used in the endovascular treatment of cerebral aneurysms.

  • the hazard ratio in survival analysis is a summary of the difference between two survival curves, representing the reduction in the risk of death on treatment compared to control, over the period of follow-up. It is a form of relative risk analysis.

  • Humanitarian Device Exemption. Similar to a pre-market approval application (PMA), but exempt from the requirement that the device’s effectiveness be proven. Limited clinical data are required to show safety and probable benefit. An approved HDE authorizes marketing of a Humanitarian Use Device (HUD). After HDE approval, use of the device requires local IRB approval and patient consent.

  • an aggregation of multiple, dilated, blood vessels.

  • a collection of extravasted blood trapped in the tissues of the skin or in an organ.

  • loss of vision of one-half of the visual field.

  • muscle weakness on one side of the body.

  • paralysis of one side of the body.

  • a reduction in the concentration of blood cells in a given volume of blood.

  • the study of the movements of the blood and of the forces concerned therein.

  • a loss of a large amount of blood in a short amount of time.

  • a stroke caused by a ruptured blood vessel and characterized by bleeding in or surrounding the brain. Subarachnoid hemorrhage from a ruptured cerebral aneurysm can lead to a hemorrhagic stroke.

  • the arrest of bleeding, either by the physiological properties of vasoconstriction and coagulation or by surgical means. Interruption of blood flow through any vessel or to any anatomical area.

  • an anionic mucopolysaccharide that acts as an anticoagulant and is used for prevention and treatment of venous and arterial thromboembolism.

  • Humanitarian Use Device. An HUD is a device that is intended to benefit patients by treating or diagnosing a disease or condition that affects fewer than 4,000 individuals in the United States per year. HUDs are marketed under HDEs.

  • a neurological scale used to determine the patient’s surgical risk following the hemorrhage of an aneurysm.

  • excess water in the brain due to blockage of CSF flow, increased production or reduced absorption.

  • hydrocephalus where flow of cerebrospinal fluid (CSF) is not blocked but there is absorption failure. Also known as "normal pressure" hydrocephalus (NPH).

  • hydrocephalus where flow of CSF is blocked.

  • expansion of the spinal cord due to increased size of the central canal of the cord which is filled with CSF.

  • excessive sensibility to touch, pain or other stimuli.

  • an increase in the number of cells in a body part.

  • elevated blood pressure.

  • an increase in the amount of extracellular fluid.

  • surgical removal of the hypophysis (pituitary gland).

  • a collection of specialized nerve cells at the base of the brain which controls the anterior and posterior pituitary secretions, and is involved in other basic regulatory functions such as temperature control and attention.

  • a localized area of necrosis (death) in a tissue, vessel or organ resulting from tissue anoxia caused by the cessation of blood flow.

  • the amount of time it takes to inflate and deflate the balloon.

  • below the tentorium.

  • a stalk extending from the base of the brain to the pituitary gland.

  • a thin, elastic layer between the intimal and medial layers of an artery.

  • the innermost lining of an artery, composed of endothelial cells. Provides a smooth, thrombiresistant surface and is nourished by the blood flowing through the artery.

  • an invasive study in which a catheter (a small tube) is placed in the artery and contrast material is injected to which makes the blood vessels visible on an x-ray image.

  • bleeding within the cerebrum as a result of trauma or aneurysm rupture.

  • within the cranial cavity or skull.

  • the buildup of plaque on the inside walls of arteries within the brain.

  • pressure within the cranium that can be caused by increase blood or fluid in a closed, non-expandable space.

  • within a theca or the dura mater membrane that surrounds the spinal canal.

  • ultrasound within a vessel or vessels used for diagnostic purposes.

  • stroke within the same hemisphere of the lesion.

  • lack of oxygen due to decreased blood supply to a body organ or part.

  • the region surrounding dead brain tissue that is close to cell death, but still potentially viable.

  • stroke caused by lack of blood supply and subsequent lack of oxygen to affected brain tissue.

  • the major veins on each side of the neck draining blood from the head toward the heart.

  • thrombotic stroke in small, deeply penetrating vessels. Often termed small vessel strokes.

  • the portion of bone that extends from the pedicle and curves around to complete the vertebral arch on the right and left sides.

  • two thin layers of fine tissue covering the brain and spinal cord (the pia mater and arachnoid).

  • inflammation of the membranes covering the brain and spinal cord.

  • a benign fatty tumor, usually composed of mature fat cells.

  • diagnostic test in which a sample of cerebrospinal fluid is "tapped" from an area just below the end of the spinal cord through a thin needle inserted into the spinal canal. Used to detect blood in the CSF.

  • Lower spine, lower back; usually consists of 5 vertebrae.

  • the channel within a tubular organ (e.g. artery).

  • a non-invasive study that is conducted in a magnetic resonance imager. The magnetic images are assembled by a computer to provide an image of the arteries in the head and neck. No contrast material is needed, but some patients may experience claustrophobia in the imager.

  • diagnostic test that produces three-dimensional images of body structures using powerful magnets and computer technology rather than x-rays.

  • tending to become progressively worse and possibly result in death.

  • symptoms produced by compression or displacement of brain tissue, specific to the brain territory around a physical mass.

  • middle layer of an artery, composed of smooth muscle tissue, provides strength to the artery by allowing constriction and/or dilation.

  • the nerve formed from the brachial plexus that supplies muscles in the anterior forearm and thumb as well as sensation of the hand. It may be compressed or trapped at the wrist in carpal tunnel syndrome.

  • the use of pharmacological agents. Sometimes also referred to as medical management or medical treatment.

  • a tumor composed of medulloblasts, which are cells that develop in the roof of the fourth ventricle (medullary velum).

  • the three membranes covering the brain and spinal cord for protection: dura mater, arachnoid, and pia mater.

  • a hard, usually vascular tumor, occurring mainly along the meningeal vessels and superior longitudinal sinus, invading the dura and skull and leading to erosion and thinning of the skull.

  • an inflammation or infection of the meninges.

  • a protrusion of the meninges of the spinal cord through a defect in the spinal column.

  • an inflammation or infection of the brain and meninges.

  • a protrusion of both the meninges and brain tissue through a skull defect.

  • a very small catheter used to deliver diagnostic and therapeutic agents such as devices used in the endovascular treatment of cerebral aneurysms. Over-the-wire microcatheters follow along a guidewire to the area of the body for treatment. Flow-directed microcatheters utilize the forward blood flow to reach their destination in the body.

  • minimum lumen diameter.

  • widely used to assess global functional outcome after stroke.

  • a radiographic process by which the spinal cord and spinal subarachnoid space are viewed and photographed after the introduction of contrast media.

  • any functional or pathologic disturbance in the spinal cord.

  • this results from the inflammatory response to vessel injury. It is the proliferation and migration of smooth muscle cells in the intima, and the synthesis of extracelluar matrix (collagen, protyoglycins). This is part of the normal tissue repair process. However, when it goes beyond the normal response it leads to restenosis. This is often called hyperplasia.

  • tumor: any new and abnormal growth, specifically one in which cell multiplication is uncontrolled and progressive.

  • a paroxysmal pain extending along the course of one or more nerves.

  • excision of part of a nerve.

  • inflammation of a nerve; may also be used to denote non-inflammatory nerve lesions of the peripheral nervous system.

  • the study of blood vessels in the brain.

  • a tumor of sympathetic nervous system origin, found mostly in infants and children.

  • a tumor of the peripheral nerves due to an abnormal collection of fibrous and insulating cells.

  • a familial condition characterized by developmental changes in the nervous system, muscles and skin, marked by numerous tumors affecting these organ system.

  • removal of scar or reactive tissue from a nerve or nerve root.

  • a tumor or new growth largely made up of nerve fibers and connective tissue.

  • any functional or pathologic disturbance in the peripheral nervous system. Localized secondary to lesion or generalized secondary to medical disorder.

  • the point of origin or focus of a morbid process.

  • super elastic metal alloy comprised of nickel and titanium. Typically used for self-expanding stents because of its shape memory and super elasticity.

  • the amount of pressure (ATMs) required to inflate the balloon to its labeled diameter.

  • lowest rate of diameter growth per ATM of pressure of all balloon types. Used for post-dilation and calcified lesions in coronary vessels.

  • an aneurysm that has not hemorrhaged.

  • the soft center of a spinal disk.

  • involuntary rapid movement of the eyes in the horizontal, vertical, or rotary planes of the eyeball.

  • the back part of the head.

  • non-nerve cells, (see glia) forming part of the supporting structure of the central nervous system.

  • a growth of new cells derived from the oligodendroglia.

  • a system that tracks over the entire length of a 300cm length guidewire.

  • “probability” level. The likelihood that the difference observed between two interventions could have arisen by chance. The usual p value is arbitrarily set at 0.05. A p value of 0.05 means that there is a 5% (1 in 20) chance that the observed difference is due to “luck” rather than due to the interventions studied.

  • swelling of the optic nerve head, can be seen in the back of the retina during eye examination.

  • paralysis of the lower part of the body including the legs.

  • numbness, tingling, or a "pins and needles" feeling.

  • the source or cause of a disease.

  • the peripheral part of the nervous system external to the brain and spinal cord from their roots to their peripheral terminations.

  • the innermost and most delicate of the three meninges covering the entire brain and spinal cord. Contains many blood vessels that reach deep into the surface of the brain.

  • the gland at the base of the brain which secretes hormones into the blood stream. Those hormones then regulate other glands including the thyroid, adrenals, and gonads. The "Master Gland."

  • the ability to accurately place the stent over the length of the lesion. This largely depends upon stent markerband visibility and degree of recoil.

  • a fatty deposit inside an arterial wall, made up of plasma lipids, cholesterol, connective tissue fibers and other cells in the intima of the vessel; an abnormal patch on or inside the body.

  • inflammation of two or more nerves simultaneously.

  • a scanning technique using low-dose radioactive glucose to measure metabolic activity of an organ.

  • use of balloon after implantation of a stent.

  • a hollow depression in the back of the skull in which the cerebellum and several other structures are located.

  • use of balloon before implantation of a stent.

  • the main result measured at the end of a study to see if a given treatment has worked.

  • sensation concerning movements of joints and position of the body in space.

  • study that actively enrolls patients in a forward looking manner (rather than looking at patient outcomes in the past).

  • failure of fusion to achieve proper union of vertebrae.

  • a collection of cerebrospinal fluid that is due to a dural leak after spine surgery, not a congenital disorder.

  • raised intracranial pressure, usually causing only headache and papilledema. No clear underlying structural abnormality.

  • the black part of the eye through which light enters; enlarges in dim light, and decreases in size in bright light.

  • ability of the catheter to transmit force from the proximal to the distal end of the catheter.

  • paralysis of all four limbs.

  • a medical doctor who has received advanced training in the treatment of persons receiving x-ray treatment for an illness.

  • a person having a PhD degree who is trained in the science dealing with the properties, changes, and interactions of continuous energy.

  • inflammation of the spinal nerve roots. Accompanied by pain and hyperesthesia.

  • a medical doctor who has received specialized training in interpreting x-rays, CTs, MRIs, and performing angiography.

  • visibility of the stent under fluoroscopy.

  • a technique that uses focused beams of radiation to treat AVMs that are sufficiently small and located in accessible areas of the brain. It causes scarring in the blood vessels of the AVM, thereby eliminating it.

  • treatment of a lesion with radiation.

  • the amount of pressure (ATMs) a balloon is designed to accept without bursting.

  • to bleed again after an initial bleed such as in an aneurysm rupture.

  • regrowth of an aneurysm.

  • the shrinkage of stent diameter following deployment.

  • a condition characterized by burning pain, abnormal sensitivity to sensory stimuli, poor circulation, and changes in the skin, muscle, bone, and joints.

  • resistant to treatment or cure from a therapy.

  • occurs after a vessel has been treated with angioplasty or stenting. It is the repair process caused by mechanical injury induced by ballooning and stenting and is different than the original plaque or atherosclerotic lesion.

  • clinical study that assesses clinical or angiographic outcomes of patients treated in the past.

  • reestablishment of blood supply to a part.

  • deficit that persists for more than 24 hours, but with complete recovery within 3 weeks.

  • superimposing a “real time” image over a stored subtracted reversed image, to enable more effective navigation through the vasculature.

  • an aneurysm that has hemorrhaged prior to coil treatment. Acute rupture has occurred within the last fifteen days and non-acute rupture has occurred over fifteen days ago.

  • a balloon-like outpouching of a vessel (the more common type of aneurysm).

  • the largest nerve in the body. It extends from the sacral plexus, emerges from the pelvis and travels deep within the buttocks. It then descends down the back of the thigh to the back of the knee at which point it divides into the common peroneal and tibial nerves. The sciatic nerve supplies sensation to the back of the thigh, outer side of the leg, and essentially the whole foot.

  • additional measures (angiographic or clinical) assessed at the end of a study as planned in the clinical protocol.

  • a stent that is delivered using a sheath. When the sheath is removed, the stent expands and deploys against the wall of the vessel where it exerts slow, constant outward pressure to maintain the lumen.

  • type of balloon material that has less diameter growth per ATM of pressure than a compliant balloon, but more than a non-compliant balloon. Typically used for angioplasty and pre-dilation, also used to deploy balloon-expandable stents.

  • a diversion or redirection of bodily fluid from one cavity or vessel to another.

  • this refers to the access or maximum opening that a stent’s cell(s) can provide to permit passage of a second balloon or stent into a side branch.

  • study performed evaluating a therapy in a single group of patients.

  • also known as cervical dystonia, is a form of dystonia characterized by intermittent spasms of the neck muscles resulting in involuntary rotation and tilting of the head. These movements are frequently painful.

  • a variation of CT imaging.

  • a narrowing of the artery lumen generally due to thrombus, atherosclerotic plaque or vasospasm in the vessel.

  • a device used to support and maintain patency of a bodily cavity, channel, or vessel.

  • surgical technique whereby the exact target (i.e., tumor, lesion, AVM) is calculated three-dimensionally utilizing CT or MRI and computer. From stereo (3D) and tactic (touch).

  • any disease process which results in the death of cells in any region of the brain. Cerebral vascular accident.

  • a measure of the depth of the strut into the lumen.

  • the width of the strut flat against the vessel wall.

  • located under the arachnoid membrane and above the pia mater.

  • an intracranial hemorrhage (bleed) into the CSF filled subarachnoid space. The pathologic hallmark of aneurysm rupture as cerebral arteries are within the subarachnoid space.

  • between the arachnoid mater and pia mater of the brain, in which flows cerebrospinal fluid.

  • a collection of blood (clot) trapped under the dura matter, the outermost membrane surrounding the brain and spinal cord.

  • between the dura mater and the arachnoid mater of the brain.

  • the nerve that originates from the superior trunk of the brachial plexus. Supplies the shoulder joint and deep shoulder structures.

  • located above the tentorium.

  • narrowing of a stent and/or vessel lumen causing clinical events (such as TIA or stroke).

  • a fluid-filled cavity in the spinal cord.

  • the measure of the catheter system’s outer diameter.

  • pertaining to or affecting the entire body as a whole.

  • noninvasive procedure in which a small probe is placed against the skull to measure blood flow velocity through the cerebral arteries with high frequency sound waves.

  • a fold of one of the meninges, the dura mater, that separates the cerebrum from the cerebellum. It runs horizontally under the back portion of the cerebrum, separating it from the cerebellum below.

  • tumor or growth made up of several different types of tissue (fat, bone, muscle, skin).

  • brain cells that lie in the upper part of the brainstem.

  • obstruction of a blood vessel with thrombotic material, or blood clot, carried by the blood from the site of origin to plug another vessel.

  • clot formation.

  • producing or tendency to produce a clot.

  • a "clot-busting" drug; such agents may be administered into veins or arteries.

  • when complete occlusion develops at the site of an atherosclerotic plaque in a cerebral artery.

  • an aggregation of platelets, fibrin, clotting factors and cellular elements of blood that adheres to blood vessel walls.

  • an episode of cerebrovascular insufficiency, usually associated with partial occlusion of an artery by atherosclerotic plague or an embolism.

  • the way a tip is designed and manufactured, typically laser bonding or adhesive bonding. Laser bonded tips provide for a lower profile compared to adhesive bonding. This also increases flexibility.

  • the measure of the tip diameter.

  • the spasmodic contraction of neck muscles drawing the head to one side with the chin pointing to the other side.

  • ability of the balloon or stent to follow, or track, the guidewire and traverse through the vessel anatomy.

  • operative method of reaching the pituitary gland or skull base traversing the nose and sinuses.

  • the wing of bone on either side of each vertebral arch where the pedicle meets the lamina.

  • the fifth cranial nerve and the largest. It is mainly sensory except for a small motor branch that supplies the muscles for chewing. The branches of the trigeminal nerve provide sensation to the eye and forehead, midface, and upper and lower jaw.

  • paroxysmal pain in the face. Pain may be so severe that it causes an involuntary grimace or "tic." (Tic Douloureux)

  • neoplasm: a new growth of tissue in which cell multiplication is uncontrolled and progressive.

  • the imaging of deep structures of the body by recording the echoes of pulses of 1-10 megahertz ultrasound reflected by tissue planes where there is a change in density.

  • constriction or narrowing of blood vessels.

  • an increase in the diameter of blood vessels.

  • a hormone secreted by the hypothalamus and stored in the posterior pituitary, which raises blood pressure and increases reabsorption of water by the kidneys.

  • an agent that constricts the arteries and raises blood pressure.

  • acute, abnormal narrowing of arteries due to irritation by blood in the subarachnoid space; often develops several days after an aneurysm rupture.

  • a small cavity or chamber such as in the heart or brain. Brain ventricles manufacture and circulate cerebrospinal fluid.

  • insertion of a small tube into the ventricles to drain cerebrospinal fluid, usually when pressure is increased.

  • inflammation and/or infection of the ventricles.

  • describing a CSF shunt from one of the ventricles in the brain to the right atrium of the heart.

  • describing a CSF shunt from one of the ventricles of the brain to the peritoneal cavity in the abdomen.

  • an x-ray study of the ventricles.

  • enlarged cerebral ventricles. (see also hydrocephalus)

  • an opening into the ventricles of the brain, such as by inserting a small, thin, hollow catheter.

  • the middle part of the cerebellum between the two hemispheres.

  • any of the 33 bones of the spinal column.

  • an abnormal sensation of rotation or movement of one's self or the environment.

  • ease with which the balloon catheter can be advanced and retracted over the guidewire.

  • the straight portion of the balloon intended to contact the vessel wall during balloon inflation.

  • application of electromagnetic radiation to produce a film or picture of a bone or soft- tissue area of the body.