Articles
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2,943 results found
Article
Owl-eyes sign (spinal cord)
The owl-eyes sign, also known as snake-eyes sign or fried-eggs sign, represents bilaterally symmetric circular to ovoid foci of high T2-weighted signals in the anterior horn cells of the spinal cord and is seen on axial MR imaging. The sagittal corollary is a "pencil-like" vertical linear high T...
Article
Caudate nucleus
Caudate nuclei are paired nuclei which along with the globus pallidus and putamen are referred to as the corpus striatum, and collectively make up the basal ganglia. The caudate nuclei have both motor and behavioral functions, in particular maintaining body and limb posture, as well as controlli...
Article
Velum interpositum
The velum interpositum is a small membrane containing a potential space just above and anterior to the pineal gland which can become enlarged to form a cavum veli interpositi.
Gross anatomy
The velum interpositum is formed by an invagination of pia mater forming a triangular membrane the apex...
Article
Migraine
Migraines are a common primary headache disorder and can present variably. Typically they consist of debilitating headaches, accompanied by an aura in one-third of patients.
Epidemiology
Migraine is a very common condition, with a 1-year prevalence of 12% 8. It is most prevalent in early-middl...
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Cerebral hyperperfusion syndrome
Cerebral hyperperfusion syndrome is a rare complication seen after treatment of long-standing severe carotid stenosis by carotid endarterectomy or carotid artery stenting. It is believed to be the result of failure of normal cerebral blood flow autoregulation.
Terminology
Cerebral hyperperfus...
Article
Choroidal fissure
The choroidal fissure, or choroid fissure, is a cleft of the medial surface of the cerebral hemisphere running immediately above the hippocampus and extends around the thalamus to the interventricular foramen of Monroe. It forms the medial wall of the lateral ventricle and attachment site for th...
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Medial posterior choroidal artery
The medial posterior choroidal artery is a small branch (often multiple - 40% of hemispheres) usually arising from the P2 segment of the PCA. It may also arise from one of the PCA branches, e.g. parieto-occiptal, calcarine, splenial artery.
It ascends deep to the rest of the PCA and supplies sm...
Article
Anterior corticospinal tract
The anterior corticospinal tract is formed at the level of the of the medullary pyramids, where the majority (90%) of descending corticospinal tract fibers decussate to form the lateral corticospinal tract. The remaining non-decussating fibers (10%) form the much smaller anterior corticospinal t...
Article
Rathke cleft cyst
Rathke cleft cysts, also known as pars intermedia cysts, are non-neoplastic, sellar or suprasellar epithelium-lined cysts arising from the embryologic remnants of Rathke pouch in the pituitary gland. They are common lesions and usually incidentally identified.
Epidemiology
common, found in ~1...
Article
Rathke pouch
Rathke pouch, also known as hypophyseal diverticulum, is an ectodermal outpouching of stomodeum (primitive oral cavity lined by ectoderm) which forms at approximately 3-4 weeks gestation and goes on to form the adenohypophysis of the pituitary gland.
Gross anatomy
The anterior wall of the pouc...
Article
Pituitary gland
The pituitary gland (a.k.a. hypophysis cerebri), together with its connections to the hypothalamus, acts as the main endocrine interface between the central nervous system and the rest of the body.
Gross anatomy
The pituitary gland sits atop the base of the skull in a concavity within the sph...
Article
Corticospinal tract
The corticospinal tract (also known as the pyramidal tract) is a descending white matter tract primarily concerned with motor function that extends caudally from the motor cortex to synapse with motor neurons of the spinal cord in the anterior horns.
Gross anatomy
Central connections
Cortico...
Article
Internal capsule
The internal capsule (TA: capsula interna) is a deep subcortical structure that contains a concentration of afferent and efferent white matter projection fibers. Anatomically, this is an important area because of the high concentration of both motor and sensory projection fibers 1,2. Afferent fi...
Article
Fornix (brain)
The fornix (plural: fornices) is the main efferent system of the hippocampus and an important part of the limbic system. It is one of the commissural fibers connecting the cerebral hemispheres.
Gross anatomy
Roughly C-shaped, the fornix extends from the hippocampus to the mammillary bodies of ...
Article
Bickerstaff encephalitis
Bickerstaff encephalitis, also known as Bickerstaff brainstem encephalitis, is a rare immune-mediated condition, often a phenotype of the anti-GQ1b antibody syndrome.
Epidemiology
Bickerstaff encephalitis is very rare. it typically affects adult patients in early to middle age 4.
Clinical pre...
Article
Miller Fisher syndrome
Miller Fisher syndrome is an immune-mediated condition characterized by the triad of cerebellar ataxia, areflexia, and external ophthalmoplegia. It is believed to represent, along with several other entities, different clinical manifestations of a similar underlying autoimmune disorder, the anti...
Article
Tuberculosis
Tuberculosis (commonly abbreviated to TB, short for tubercle bacillus) encompasses an enormously wide disease spectrum affecting multiple organs and body systems predominantly caused by Mycobacterium tuberculosis. A small proportion can also be caused by Mycobacterium bovis through drinking unpa...
Article
Optic neuropathy
Optic neuropathy is a broad term and can result from a variety of causes.
Pathology
genetic
Leber hereditary optic neuropathy
compression or trauma (traumatic optic neuropathy)
optic nerve sheath meningioma
progressive diaphyseal dysplasia
thyroid-associated orbitopathy
shear injury
inf...
Article
Chronic traumatic encephalopathy
Chronic traumatic encephalopathy (CTE) is a neurodegenerative tauopathy that is thought to result from mild repetitive head injury. The diagnosis can only be made by neuropathological examination.
Terminology
Chronic traumatic encephalopathy refers to a specific neuropathological diagnosis, of...
Article
Vestibular neuritis
Vestibular neuritis, also known as acute unilateral vestibulopathy (AUVP) or vestibular neuronitis, refers to presumed inflammation of the vestibular nerve/vestibulocochlear nerve. It can be associated with labyrinthitis.
The vestibular nerve is a large division of cranial nerve eight (CN VIII)...