Absence of the Septum Pellucidum Information Page
... Absence of the septum pellucidum (ASP) is a rare disorder characterized by abnormal development of a thin membrane located at the midline of the brain. The disorder usually occurs with other cranial a...

Agenesis of the Corpus Callosum Information Page
... Agenesis of the corpus callosum (ACC) is a rare birth defect in which the structure that connects the two hemispheres of the brain (the corpus callosum) is partially or completely absent. ACC can occu...

Aicardi Syndrome Information Page
... Aicardi Syndrome is a rare genetic disorder characterized by the partial or complete absence of the structure that links the two hemispheres of the brain, the corpus callosum. The disorder affects onl...

Chiari Malformation Information Page
... Arnold-Chiari Malformation is a condition in which the cerebellum portion of the brain protrudes into the spinal canal. It may or may not be apparent at birth. Arnold-Chiari I type malformation usuall...

Arteriovenous Malformation Information Page
... An arteriovenous malformation (AVM) is a congenital disorder characterized by a complex, tangled web of arteries and veins. An AVM may occur in the brain, brainstem, or spinal cord and is caused by ab...

Cavernous Malformation Information Page
... Cavernous malformation is a rare disorder of the capillaries and smallest veins in one part of the brain. The disorder occurs when a blood-filled mass resembling a tumor, called a hemangioma, forms. S...

Cerebellar Hypoplasia Information Page
... Cerebellar hypoplasia is a developmental disorder characterized by the incomplete or underdevelopment of the cerebellum. It may be genetic, or occur sporadically. Cerebellar hypoplasia may be caused b...

Soto''s Syndrome Information Page
... Soto's syndrome is a rare genetic disorder characterized by excessive physical growth during the first 2 to 3 years of life. The disorder may be accompanied by mild mental retardation, delayed mot...

Coffin Lowry Syndrome Information Page
... Coffin-Lowry syndrome is a rare genetic disorder characterized by craniofacial (head and facial) and skeletal abnormalities, mental retardation, short stature, and hypotonia. Characteristic facial fea...

Craniosynostosis Information Page
... Craniosynostosis is a birth defect of the brain characterized by the premature closure of one or more of the fibrous joints between the bones of the skull (called the cranial sutures) before brain gro...

Dandy-Walker Syndrome Information Page
... Dandy-Walker Syndrome is a congenital brain malformation involving the cerebellum (an area at the back of the brain that controls movement) and the fluid filled spaces around it. The key features of t...

Holoprosencephaly Information Page
... Holoprosencephaly is a disorder caused by the failure of the prosencephalon (the embryonic forebrain) to sufficiently divide into the double lobes of the cerebral hemispheres. The result is a single-l...

Hydranencephaly Information Page
... Hydranencephaly is a rare condition in which the brain's cerebral hemispheres are absent and replaced by sacs filled with cerebrospinal fluid. An infant with hydranencephaly may appear normal at b...

Joubert Syndrome Information Page
... Joubert syndrome is a rare brain malformation characterized by the absence or underdevelopment of the cerebellar vermis - an area of the brain that controls balance and coordination. The most common f...

Lissencephaly Information Page
... Lissencephaly, which literally means "smooth brain," is a rare, gene-linked brain malformation characterized by the absence of normal convolutions (folds) in the cerebral cortex and an abnormally smal...

Megalencephaly Information Page
... Megalencephaly, also called macrencephaly, is a condition in which there is an abnormally large, heavy, and usually malfunctioning brain. By definition, the brain weight is greater than average for th...

Microcephaly Information Page
... Microcephaly is a rare, neurological disorder in which the circumference of the head is smaller than the average for the age and gender of the infant or child. Microcephaly may be congenital (present ...

Moyamoya Disease Information Page
... Moyamoya disease is a rare, progressive cerebrovascular disorder characterized by the narrowing or occlusion of major blood vessels leading into the brain, and the formation of abnormal blood vessels ...

Neuronal Migration Disorders Information Page
... Neuronal migration disorders (NMDs) are a group of birth defects caused by the abnormal migration of neurons in the developing brain and nervous system. In the developing brain, neurons must migrate f...

Porencephaly Information Page
... Porencephaly is an extremely rare disorder of the central nervous system involving cysts or cavities in a cerebral hemisphere. The cysts or cavities are usually the remnants of destructive lesions (du...

Schizencephaly Information Page
... Schizencephaly is an extremely rare developmental disorder characterized by abnormal slits, or clefts, in the brain's cerebral hemispheres. Schizencephaly is a form of porencephaly in which there ...

Apert syndrome
... Apert syndrome is a genetic disorder characterized by the premature fusion of certain bones of the skull (craniosynostosis), which prevents further growth of the skull and affects the shape of the hea...

Beare-Stevenson cutis gyrata syndrome
... Beare-Stevenson cutis gyrata syndrome is a genetic disorder characterized by skin abnormalities and the premature fusion of certain bones of the skull (craniosynostosis), which prevents further growth...

Coffin-Lowry syndrome
... Coffin-Lowry syndrome is a condition associated with mental retardation and delayed development, characteristic facial features, and skeletal abnormalities. Males are usually more severely affected th...

Crouzon syndrome
... Crouzon syndrome is a genetic disorder characterized by the premature joining of certain bones of the skull (craniosynostosis), which affects the shape of the head and face. Many of the signs of Crouz...

Crouzonodermoskeletal syndrome
... Crouzonodermoskeletal syndrome is a genetic disorder characterized by the premature joining of certain bones of the skull (craniosynostosis) and a skin disorder called acanthosis nigricans. Some of th...

Jackson-Weiss syndrome
... Jackson-Weiss syndrome is a genetic disorder characterized by foot abnormalities and the premature fusion of certain bones of the skull (craniosynostosis), which prevents further growth of the skull a...

Muenke syndrome
... Muenke syndrome is an inherited condition characterized by the premature closure of certain bones of the skull (coronal synostosis), which affects the shape of the head and face. The primary feature o...

Pfeiffer syndrome
... Pfeiffer syndrome is a genetic disorder characterized by the premature fusion of certain bones of the skull (craniosynostosis), which prevents further growth of the skull and affects the shape of the ...

Arteriovenous Malformations and Other Vascular Lesions of the Central Nervous System Fact Sheet Fact Sheet
... Arteriovenous malformations (AVMs) are defects of the circulatory system that are generally believed to arise during embryonic or fetal development or soon after birth. They are comprised of snarled t...

Thanatophoric dysplasia
... Thanatophoric dysplasia is a severe inherited skeletal disorder characterized by extremely short limbs and folds of extra skin on the arms and legs. Genetic changes are related to the following types ...