Central Nervous System Vascular Malformations: Congenital, inherited, or acquired abnormalities involving ARTERIES; VEINS; or venous sinuses in the BRAIN; SPINAL CORD; and MENINGES.Vascular Malformations: A spectrum of congenital, inherited, or acquired abnormalities in BLOOD VESSELS that can adversely affect the normal blood flow in ARTERIES or VEINS. Most are congenital defects such as abnormal communications between blood vessels (fistula), shunting of arterial blood directly into veins bypassing the CAPILLARIES (arteriovenous malformations), formation of large dilated blood blood-filled vessels (cavernous angioma), and swollen capillaries (capillary telangiectases). In rare cases, vascular malformations can result from trauma or diseases.Arteriovenous Malformations: Abnormal formation of blood vessels that shunt arterial blood directly into veins without passing through the CAPILLARIES. They usually are crooked, dilated, and with thick vessel walls. A common type is the congenital arteriovenous fistula. The lack of blood flow and oxygen in the capillaries can lead to tissue damage in the affected areas.Intracranial Arteriovenous Malformations: Congenital vascular anomalies in the brain characterized by direct communication between an artery and a vein without passing through the CAPILLARIES. The locations and size of the shunts determine the symptoms including HEADACHES; SEIZURES; STROKE; INTRACRANIAL HEMORRHAGES; mass effect; and vascular steal effect.Central Nervous System: The main information-processing organs of the nervous system, consisting of the brain, spinal cord, and meninges.Hemangioma: A vascular anomaly due to proliferation of BLOOD VESSELS that forms a tumor-like mass. The common types involve CAPILLARIES and VEINS. It can occur anywhere in the body but is most frequently noticed in the SKIN and SUBCUTANEOUS TISSUE. (from Stedman, 27th ed, 2000)Telangiectasia, Hereditary Hemorrhagic: An autosomal dominant vascular anomaly characterized by telangiectases of the skin and mucous membranes and by recurrent gastrointestinal bleeding. This disorder is caused by mutations of a gene (on chromosome 9q3) which encodes endoglin, a membrane glycoprotein that binds TRANSFORMING GROWTH FACTOR BETA.Hemangioma, Cavernous, Central Nervous System: A vascular anomaly composed of a collection of large, thin walled tortuous VEINS that can occur in any part of the central nervous system but lack intervening nervous tissue. Familial occurrence is common and has been associated with a number of genes mapped to 7q, 7p and 3q. Clinical features include SEIZURES; HEADACHE; STROKE; and progressive neurological deficit.Lymphatic Abnormalities: Congenital or acquired structural abnormalities of the lymphatic system (LYMPHOID TISSUE) including the lymph vessels.Parotid Region: The region of the face on either side, around the PAROTID GLAND.Central Nervous System Diseases: Diseases of any component of the brain (including the cerebral hemispheres, diencephalon, brain stem, and cerebellum) or the spinal cord.Hemangioma, Cavernous: A vascular anomaly that is a collection of tortuous BLOOD VESSELS and connective tissue. This tumor-like mass with the large vascular space is filled with blood and usually appears as a strawberry-like lesion in the subcutaneous areas of the face, extremities, or other regions of the body including the central nervous system.Double-Balloon Enteroscopy: Endoscopy of the small intestines accomplished while advancing the endoscope into the intestines from the stomach by alternating the inflation of two balloons, one on an innertube of the endoscope and the other on an overtube.Arteriovenous Fistula: An abnormal direct communication between an artery and a vein without passing through the CAPILLARIES. An A-V fistula usually leads to the formation of a dilated sac-like connection, arteriovenous aneurysm. The locations and size of the shunts determine the degree of effects on the cardiovascular functions such as BLOOD PRESSURE and HEART RATE.Sclerotherapy: Treatment of varicose veins, hemorrhoids, gastric and esophageal varices, and peptic ulcer hemorrhage by injection or infusion of chemical agents which cause localized thrombosis and eventual fibrosis and obliteration of the vessels.Port-Wine Stain: A vascular malformation of developmental origin characterized pathologically by ectasia of superficial dermal capillaries, and clinically by persistent macular erythema. In the past, port wine stains have frequently been termed capillary hemangiomas, which they are not; unfortunately this confusing practice persists: HEMANGIOMA, CAPILLARY is neoplastic, a port-wine stain is non-neoplastic. Port-wine stains vary in color from fairly pale pink to deep red or purple and in size from a few millimeters to many centimeters in diameter. The face is the most frequently affected site and they are most often unilateral. (From Rook et al., Textbook of Dermatology, 5th ed, p483)Cerebral Veins: Veins draining the cerebrum.Angiodysplasia: Acquired degenerative dilation or expansion (ectasia) of normal BLOOD VESSELS, often associated with aging. They are isolated, tortuous, thin-walled vessels and sources of bleeding. They occur most often in mucosal capillaries of the GASTROINTESTINAL TRACT leading to GASTROINTESTINAL HEMORRHAGE and ANEMIA.Klippel-Trenaunay-Weber Syndrome: A congenital disorder that is characterized by a triad of capillary malformations (HEMANGIOMA), venous malformations (ARTERIOVENOUS FISTULA), and soft tissue or bony hypertrophy of the limb. This syndrome is caused by mutations in the VG5Q gene which encodes a strong angiogenesis stimulator.Skin Diseases, Vascular: Skin diseases affecting or involving the cutaneous blood vessels and generally manifested as inflammation, swelling, erythema, or necrosis in the affected area.Central Nervous System Neoplasms: Benign and malignant neoplastic processes that arise from or secondarily involve the brain, spinal cord, or meninges.Arnold-Chiari Malformation: A group of congenital malformations involving the brainstem, cerebellum, upper spinal cord, and surrounding bony structures. Type II is the most common, and features compression of the medulla and cerebellar tonsils into the upper cervical spinal canal and an associated MENINGOMYELOCELE. Type I features similar, but less severe malformations and is without an associated meningomyelocele. Type III has the features of type II with an additional herniation of the entire cerebellum through the bony defect involving the foramen magnum, forming an ENCEPHALOCELE. Type IV is a form a cerebellar hypoplasia. Clinical manifestations of types I-III include TORTICOLLIS; opisthotonus; HEADACHE; VERTIGO; VOCAL CORD PARALYSIS; APNEA; NYSTAGMUS, CONGENITAL; swallowing difficulties; and ATAXIA. (From Menkes, Textbook of Child Neurology, 5th ed, p261; Davis, Textbook of Neuropathology, 2nd ed, pp236-46)Embolization, Therapeutic: A method of hemostasis utilizing various agents such as Gelfoam, silastic, metal, glass, or plastic pellets, autologous clot, fat, and muscle as emboli. It has been used in the treatment of spinal cord and INTRACRANIAL ARTERIOVENOUS MALFORMATIONS, renal arteriovenous fistulas, gastrointestinal bleeding, epistaxis, hypersplenism, certain highly vascular tumors, traumatic rupture of blood vessels, and control of operative hemorrhage.Nervous System: The entire nerve apparatus, composed of a central part, the brain and spinal cord, and a peripheral part, the cranial and spinal nerves, autonomic ganglia, and plexuses. (Stedman, 26th ed)Brain: The part of CENTRAL NERVOUS SYSTEM that is contained within the skull (CRANIUM). Arising from the NEURAL TUBE, the embryonic brain is comprised of three major parts including PROSENCEPHALON (the forebrain); MESENCEPHALON (the midbrain); and RHOMBENCEPHALON (the hindbrain). The developed brain consists of CEREBRUM; CEREBELLUM; and other structures in the BRAIN STEM.Magnetic Resonance Imaging: Non-invasive method of demonstrating internal anatomy based on the principle that atomic nuclei in a strong magnetic field absorb pulses of radiofrequency energy and emit them as radiowaves which can be reconstructed into computerized images. The concept includes proton spin tomographic techniques.Congenital Abnormalities: Malformations of organs or body parts during development in utero.Magnetic Resonance Angiography: Non-invasive method of vascular imaging and determination of internal anatomy without injection of contrast media or radiation exposure. The technique is used especially in CEREBRAL ANGIOGRAPHY as well as for studies of other vascular structures.Tomography, X-Ray Computed: Tomography using x-ray transmission and a computer algorithm to reconstruct the image.Abnormalities, MultipleSturge-Weber Syndrome: A non-inherited congenital condition with vascular and neurological abnormalities. It is characterized by facial vascular nevi (PORT-WINE STAIN), and capillary angiomatosis of intracranial membranes (MENINGES; CHOROID). Neurological features include EPILEPSY; cognitive deficits; GLAUCOMA; and visual defects.Gastrointestinal Hemorrhage: Bleeding in any segment of the GASTROINTESTINAL TRACT from ESOPHAGUS to RECTUM.Sclerosing Solutions: Chemical agents injected into blood vessels and lymphatic sinuses to shrink or cause localized THROMBOSIS; FIBROSIS, and obliteration of the vessels. This treatment is applied in a number of conditions such as VARICOSE VEINS; HEMORRHOIDS; GASTRIC VARICES; ESOPHAGEAL VARICES; PEPTIC ULCER HEMORRHAGE.Cerebral Hemorrhage: Bleeding into one or both CEREBRAL HEMISPHERES including the BASAL GANGLIA and the CEREBRAL CORTEX. It is often associated with HYPERTENSION and CRANIOCEREBRAL TRAUMA.Central Nervous System Venous Angioma: A vascular anomaly characterized by a radial or wedge-shaped arrangement of dilated VEINS draining into a larger vein in the brain, spinal cord, or the meninges. Veins in a venous angioma are surrounded by normal nervous tissue, unlike a CENTRAL NERVOUS SYSTEM CAVERNOUS HEMANGIOMA that lacks intervening nervous tissue. Drainage of venous angioma is fully integrated with the body's venous system, therefore, in most cases there is no clinical signs and rare bleeding.Angiomatosis: A condition with multiple tumor-like lesions caused either by congenital or developmental malformations of BLOOD VESSELS, or reactive vascular proliferations, such as in bacillary angiomatosis. Angiomatosis is considered non-neoplastic.Telangiectasis: Permanent dilation of preexisting blood vessels (CAPILLARIES; ARTERIOLES; VENULES) creating small focal red lesions, most commonly in the skin or mucous membranes. It is characterized by the prominence of skin blood vessels, such as vascular spiders.Angiography: Radiography of blood vessels after injection of a contrast medium.Central Nervous System Infections: Pathogenic infections of the brain, spinal cord, and meninges. DNA VIRUS INFECTIONS; RNA VIRUS INFECTIONS; BACTERIAL INFECTIONS; MYCOPLASMA INFECTIONS; SPIROCHAETALES INFECTIONS; fungal infections; PROTOZOAN INFECTIONS; HELMINTHIASIS; and PRION DISEASES may involve the central nervous system as a primary or secondary process.Spinal Cord: A cylindrical column of tissue that lies within the vertebral canal. It is composed of WHITE MATTER and GRAY MATTER.Dura Mater: The outermost of the three MENINGES, a fibrous membrane of connective tissue that covers the brain and the spinal cord.Proteus Syndrome: Hamartoneoplastic malformation syndrome of uncertain etiology characterized by partial GIGANTISM of the hands and/or feet, asymmetry of the limbs, plantar hyperplasia, hemangiomas (HEMANGIOMA), lipomas (LIPOMA), lymphangiomas (LYMPHANGIOMA), epidermal NEVI; MACROCEPHALY; cranial HYPEROSTOSIS, and long-bone overgrowth. Joseph Merrick, the so-called "elephant man", apparently suffered from Proteus syndrome and not NEUROFIBROMATOSIS, a disorder with similar characteristics.Spinal Cord Diseases: Pathologic conditions which feature SPINAL CORD damage or dysfunction, including disorders involving the meninges and perimeningeal spaces surrounding the spinal cord. Traumatic injuries, vascular diseases, infections, and inflammatory/autoimmune processes may affect the spinal cord.Veins: The vessels carrying blood away from the capillary beds.Angiography, Digital Subtraction: A method of delineating blood vessels by subtracting a tissue background image from an image of tissue plus intravascular contrast material that attenuates the X-ray photons. The background image is determined from a digitized image taken a few moments before injection of the contrast material. The resulting angiogram is a high-contrast image of the vessel. This subtraction technique allows extraction of a high-intensity signal from the superimposed background information. The image is thus the result of the differential absorption of X-rays by different tissues.Hemangioendothelioma: A neoplasm derived from blood vessels, characterized by numerous prominent endothelial cells that occur singly, in aggregates, and as the lining of congeries of vascular tubes or channels. Hemangioendotheliomas are relatively rare and are of intermediate malignancy (between benign hemangiomas and conventional angiosarcomas). They affect men and women about equally and rarely develop in childhood. (From Stedman, 25th ed; Holland et al., Cancer Medicine, 3d ed, p1866)Nevus, Blue: Usually a benign tumor, that commonly presents as a solitary blue nodule with spindled MELANOCYTES covered by smooth SKIN. Several variants have been identified, one variant being malignant. The blue color is caused by large, densely packed melanocytes deep in the DERMIS of the nevus. In CHILDREN, they usually occur on the BUTTOCKS and LUMBOSACRAL REGION and are referred to as cellular blue nevi. Malignant blue nevi are more commonly found on the SCALP.Blood Vessels: Any of the tubular vessels conveying the blood (arteries, arterioles, capillaries, venules, and veins).Cardiac Output, High: A state of elevated cardiac output due to conditions of either increased hemodynamic demand or reduced cardiac oxygen output. These conditions may include ANEMIA; ARTERIOVENOUS FISTULA; THYROTOXICOSIS; PREGNANCY; EXERCISE; FEVER; and ANOXIA. In time, compensatory changes of the heart can lead to pathological form of high cardiac output and eventual HEART FAILURE.Cyanoacrylates: A group of compounds having the general formula CH2=C(CN)-COOR; it polymerizes on contact with moisture; used as tissue adhesive; higher homologs have hemostatic and antibacterial properties.Cerebral Angiography: Radiography of the vascular system of the brain after injection of a contrast medium.Nervous System Malformations: Structural abnormalities of the central or peripheral nervous system resulting primarily from defects of embryogenesis.Peripheral Nervous System: The nervous system outside of the brain and spinal cord. The peripheral nervous system has autonomic and somatic divisions. The autonomic nervous system includes the enteric, parasympathetic, and sympathetic subdivisions. The somatic nervous system includes the cranial and spinal nerves and their ganglia and the peripheral sensory receptors.Intracranial Hemorrhages: Bleeding within the SKULL, including hemorrhages in the brain and the three membranes of MENINGES. The escape of blood often leads to the formation of HEMATOMA in the cranial epidural, subdural, and subarachnoid spaces.Vascular Headaches: Secondary headache disorders attributed to a variety of cranial or cervical vascular disorders, such as BRAIN ISCHEMIA; INTRACRANIAL HEMORRHAGES; and CENTRAL NERVOUS SYSTEM VASCULAR MALFORMATIONS.Infant, Newborn: An infant during the first month after birth.Vascular Neoplasms: Neoplasms located in the vasculature system, such as ARTERIES and VEINS. They are differentiated from neoplasms of vascular tissue (NEOPLASMS, VASCULAR TISSUE), such as ANGIOFIBROMA or HEMANGIOMA.Cerebral Arteries: The arterial blood vessels supplying the CEREBRUM.Azygos Vein: A vein which arises from the right ascending lumbar vein or the vena cava, enters the thorax through the aortic orifice in the diaphragm, and terminates in the superior vena cava.Pons: The front part of the hindbrain (RHOMBENCEPHALON) that lies between the MEDULLA and the midbrain (MESENCEPHALON) ventral to the cerebellum. It is composed of two parts, the dorsal and the ventral. The pons serves as a relay station for neural pathways between the CEREBELLUM to the CEREBRUM.Neurosurgical Procedures: Surgery performed on the nervous system or its parts.