Articles

Articles are a collaborative effort to provide a single canonical page on all topics relevant to the practice of radiology. As such, articles are written and edited by countless contributing members over a period of time. A global group of dedicated editors oversee accuracy, consulting with expert advisers, and constantly reviewing additions.

2,648 results found
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Dorsal vagal nucleus

The dorsal vagal nucleus, also known as the vagal nucleus, dorsal nucleus of the vagus nerve or the dorsal motor nucleus of the vagus nerve, is a elongated nucleus within the medulla oblongata that provides parasympathetic motor innervation to the viscera of the thorax and abdomen. It is the lar...
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Double density sign (berry aneurysm)

Double density sign of berry aneurysms refers to the angiographic appearance of a small intracranial aneurysm projecting in front or behind a vessel of similar caliber. As such, the border of the aneurysm cannot easily be seen, but the extra contrast within it can be seen as a rounded area of in...
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Double density sign (disambiguation)

The double density sign can refer to several radiological signs: double density sign (left atrial enlargement) double density sign (berry aneurysm) double density sign (osteoid osteoma)
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Double density sign (osteoid osteoma)

The double density sign, also sometimes clumsily referred to as the hotter spot within hot area sign, is a bone scan sign of an osteoid osteoma. It refers to a central focus of intense uptake (the nidus) within a surrounding lower, but nonetheless increased uptake, rim. See also double densit...
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Double inversion recovery sequence

Double inversion recovery (DIR) is an inversion recovery MRI pulse sequence that uses two different inversion pulses. The technique can be used to suppress signal from two different tissues or to suppress signal that moved between the two pulses. In the first instance, used in neuroimaging, two...
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Double panda sign

The double panda sign refers to the combination of the face of the giant panda and face of the miniature panda (cub of the giant panda) seen on T2 weighted images of midbrain and pons respectively in Wilson disease. The midbrain face of the giant panda sign consists of normal intensity of red n...
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Double skull sign (cephalohematoma)

The double skull sign is an eggshell calcification seen on CT in early cases of calcified cephalohematomas.
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Doughnut sign (orbit)

The doughnut sign of optic nerve sheath meningioma refers to the appearance of this tumor on coronal CT/MRI. The meningioma forms a thick cuff of enhancing tumor around the central non-enhancing optic nerve, mimicking the appearance of a ring doughnut. It is the coronal equivalent of the tram-tr...
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Down syndrome

Down syndrome (or trisomy 21) is the most common trisomy and also the commonest chromosomal disorder. It is a major cause of intellectual disability, and also has numerous multisystem manifestations. Epidemiology The approximate worldwide incidence is approximately 1 in 800 live births 15. The...
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Dravet syndrome

Dravet syndrome, previously known as severe myoclonic epilepsy of infancy (SMEI), is a rare form of epilepsy usually presenting in the first 1-2 years of life. Clinical presentation The typical presentation occurs during the first six months to one year of life as tonic-clonic seizures in a fe...
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Drop metastases (mnemonic)

The primary intracerebral malignancies that may cause drop metastases to the subarachnoid space are: glioblastoma (GBM) and anaplastic astrocytoma medulloblastoma sPNET ependymoma germinoma choroid plexus carcinoma pineoblastoma/pineocytoma These can be remembered using this mnemonic: G...
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Dual rim sign (brain abscess)

The dual or double rim sign is seen on MRI in approximately 75% of cerebral abscesses and is helpful in distinguishing an abscess from a glioblastoma.  On both susceptibility weighted imaging (SWI) and T2WI it consists of two concentric rims surrounding the abscess cavity, outer one of which is...
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Duane syndrome

Duane syndrome, also known as Duane retraction syndrome, is a rare congenital disease characterized by non-progressive strabismus. It is caused by a variable degree of abnormal development of one or both 6th cranial nerves (CN VI). Epidemiology It presents during childhood and it accounts for ...
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Dumbbell appearance of spinal tumors

The dumbbell appearance of spinal tumors refers to a tumor which has both a component within the canal and a component in the paravertebral space contiguous with each other via a thinner tumor component traversing the neural exit foramen. The appearance can be seen in: spinal nerve sheath tumo...
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Duplicated middle cerebral artery

The duplicated middle cerebral artery is an anatomical variant in which there are two middle cerebral arteries originating from the distal end of the internal carotid artery. Supply The duplicated artery supplies the anterior temporal lobe. Differential diagnosis It should not be confused wi...
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Dural arteriovenous fistula

Dural arteriovenous fistulas (dAVF) are a heterogeneous collection of conditions that share arteriovenous shunts from dural vessels. They present variably with hemorrhage or venous hypertension and can be challenging to treat. Epidemiology Most dural arteriovenous fistulas present in adulthood...
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Dural arteriovenous shunts

Dural arteriovenous shunts (DAVS) are rare congenital arteriovenous malformations (CAVMs). On the basis of clinical and anatomical features DAVS have three different types: dural sinus malformations (DSMs) infantile or juvenile DAVS (IDAVS) adult DAVS (ADAVS)
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Dural ectasia

Dural ectasia refers to ballooning or widening of the dural sac which can result in posterior vertebral scalloping and is associated with herniation of nerve root sleeves. Clinical presentation Patients with dural ectasia may present with low back pain or radicular pain in the buttocks or legs...
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Dural enhancement

Pachymeningeal enhancement, also known as dura-arachnoid enhancement 4, refers to a dural and outer layer of arachnoid pattern of enhancement seen following contrast administration and may occur in the conditions listed below: infection intracranial tumor metastases (meningeal carcinomatosis-...
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Dural masses

Dural masses can be the result of a number of different tumors and conditions, although meningiomas are by far the most common. The differential of a dural mass includes: meningioma hemangiopericytoma primary dural lymphoma Rosai-Dorfman disease solitary fibrous tumor of the dura primary i...
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Dural metastases

Dural or pachymeningeal metastases are a relatively common cause of dural masses, although they are less common than brain metastases and meningiomas. They can occur both within the spine and intracranially - this article is focused on intracranial dural masses.  Clinical presentation Patients...
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Dural osteoma

Dural osteomas are a cause of focal intracranial calcification (colloquially known as brain stones). They are difficult to differentiate from an ossified "burnt out" meningiomas and ossification of the falx. Some reports are actually contradictory 1,4, suggesting that at least some lesions have ...
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Dural sinus malformations

Dural sinus malformations (DSMs) are congenital vascular malformations characterized by massive dilatation of one or more dural venous sinuses. This condition is typically associated with arteriovenous shunts (DAVS). Subtypes There are two types of dural sinus malformations (DSM): DSMs involv...
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Dural sinus occlusive disease

Dural sinus occlusive disease (DSOD) is an infective form of dural sinus thrombosis (thrombophlebitis) commonly seen in the setting of acute otomastoiditis. It typically presents with: severe headaches high fevers sixth nerve palsy - due to involvement of Dorello's canal altered conscious st...
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Dural tail sign

The dural tail sign occurs as a result of thickening and enhancement of the dura and is most often seen adjacent to a meningioma. Initially, the sign was felt to be pathognomonic of meningiomas, however as radiologist's experience grew, it has become increasingly noted to be present in many oth...
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Dural tail sign (mnemonic)

A useful mnemonic to remember differential diagnoses associated with a dural tail sign is: My Scary Dog Likes To Stand Guard Mnemonic M: meningioma S: sarcoidosis D: dural metastases L: lymphoma T: tuberculoma S: schwannoma G: glioma
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Dural venous sinuses

Dural venous sinuses are venous channels located intracranially between the two layers of the dura mater (endosteal layer and meningeal layer). They can be conceptualised as trapped epidural veins. Unlike other veins in the body, they run alone, not parallel to arteries. Furthermore, they are va...
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Dural venous sinus thrombosis

Dural venous sinus thrombosis (plural: thromboses) is a subset of cerebral venous thrombosis, often coexisting with cortical or deep vein thrombosis, and presenting in similar fashions, depending mainly on which sinus is involved. As such, please refer to the cerebral venous thrombosis article ...
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Dura mater

The dura mater, also known as the pachymeninx (plural: pachymeninges), is the tough outer layer of the meninges that surrounds the central nervous system and is pierced by the cranial nerves, the internal carotid arteries and the vertebral arteries.  Intracranially, it is formed by two layers: ...
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Duret hemorrhage

Duret hemorrhage is a small hemorrhage (or multiple hemorrhages) seen in the medulla or pons of patients who are rapidly developing brain herniation, especially central herniation.  Pathology Raised supratentorial pressure causes the brainstem and mesial temporal lobes to be forced downwards t...
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Dyke-Davidoff-Masson syndrome

Dyke-Davidoff-Masson syndrome is a condition characterized by hemicerebral atrophy/hypoplasia secondary to brain insult usually in fetal or early childhood period and is accompanied by ipsilateral compensatory osseous hypertrophy and contralateral hemiparesis. It is characterized by: thickenin...
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Dynamic contrast enhanced (DCE) MR perfusion

Dynamic contrast-enhanced (DCE) MR perfusion, sometimes also referred to as permeability MRI, is one of the main MRI perfusion techniques which calculates perfusion parameters by evaluating T1 shortening induced by a gadolinium-based contrast bolus passing through tissue. The most commonly calcu...
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Dynamic susceptibility contrast (DSC) MR perfusion

Dynamic susceptibility contrast (DSC) MR perfusion is one of the most frequently used techniques for MRI perfusion, and relies on the susceptibility induced signal loss on T2*-weighted sequences which results from a bolus of gadolinium-based contrast passing through a capillary bed. The most com...
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Dysembryoplastic neuroepithelial tumor

Dysembryoplastic neuroepithelial tumors (DNET) are benign (WHO Grade I) slow growing glioneuronal tumors arising from either cortical or deep grey matter. The vast majority are centered in cortical grey matter, arise from secondary germinal layers, and are frequently associated with cortical dys...
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Dysgenesis of the corpus callosum

Dysgenesis of the corpus callosum may be complete (agenesis) or partial and represents an in utero developmental anomaly. It can be divided into: primary agenesis: the corpus callosum never forms secondary dysgenesis: the corpus callosum forms normally and is subsequently destroyed Epidemiolo...
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Dysgerminoma

A dysgerminoma refers to a class of tumor with germ cell origin. This can refer to: CNS dysgerminoma ovarian dysgerminoma See also germ cell tumors
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Dysmyelinating disorders

Dysmyelinating disorders are a subset of white matter disorders characterized by abnormal myelination 1. They include numerous inherited conditions that are characterized by a defective structure and function of the myelin sheath 2.  Terminology Dysmyelinating disorders are often thought of be...
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Early DWI reversal in ischemic stroke

Early DWI reversal in ischemic stroke (also referred to as diffusion lesion reversal) is encountered early in the course of ischemic infarction, most frequently in the setting of reperfusion within 3 to 6 hours of onset 1. DWI reversal is defined as the interval disappearance of the initially-v...
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Ears of the lynx sign (brain)

The ears of the lynx sign refers to abnormal T2/FLAIR cone-shaped hyperintensity at the tip of the frontal horn of the lateral ventricles in the region of forceps minor which resembles the tufts of hair crowning the ears of a lynx. This sign is seen in hereditary spastic paraplegia with thin co...
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Eastern equine encephalitis

Eastern equine encephalitis (EEE) is one of many viral encephalitides and results from infection with the eastern equine encephalitis virus. Clinical presentation Most patients have non-specific viral prodromal symptoms for approximately one week, including fevers, headache, nausea and vomitin...
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EBV associated smooth muscle tumor

Epstein-Barr virus-associated smooth muscle tumors (EBV-SMT) are rare and encountered in immunocompromised individuals. Epidemiology These tumors are generally exceedingly rare, and only seen with any frequency in the setting of immunosuppression, particularly in HIV/AIDS patients, but also po...
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EBV-positive diffuse large B-cell lymphoma, NOS

EBV-positive diffuse large B-cell lymphoma, NOS (not otherwise specified) is one of the immunodeficiency-associated CNS lymphomas, usually seen in elderly individuals. Unlike other EBV-associated CNS lymphomas, these individuals do not have a defined cause for immunosuppression. It is believed t...
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Eccentric target sign (cerebral toxoplasmosis)

The eccentric target sign is considered pathognomonic for cerebral toxoplasmosis. It is seen on postcontrast MRI/CT as a ring enhancing lesion with an eccentrically located enhancing mural nodule. It is believed that this mural nodule is an extension from the abscess wall itself with inflamed ve...
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Ecchordosis physaliphora

Ecchordosis physaliphora is a congenital benign hamartomatous lesion derived from notochord remnants, usually located in the retroclival prepontine region, but can be found anywhere from the skull base to the sacrum.  Terminology There has been some controversy as to whether intradural chordom...
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Ectopia lentis

Ectopia lentis refers to subluxation or dislocation of the lens of the eye secondary to dysfunction or disruption of zonular fibers. It is most commonly due to trauma. The commonest atraumatic etiologies are Marfan syndrome and homocystinuria. Pathology Etiology trauma systemic and syndromic...
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Ectopic posterior pituitary

An ectopic posterior pituitary reflects a disruption of normal embryogenesis of the posterior pituitary and is one of the more common causes of pituitary dwarfism. Although it can be an isolated abnormality, numerous other congenital central nervous system malformations have been identified. Whe...
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Edinburgh criteria for lobar intracerebral hemorrhage associated with cerebral amyloid angiopathy

The Edinburgh criteria were proposed in 2018 in order to diagnose lobar intracerebral hemorrhage associated with cerebral amyloid angiopathy (CAA) 1. They can potentially be used to rule CAA-associated lobar hemorrhage either in or out, but require external validation in other patient population...
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Edinger-Westphal nucleus

The Edinger-Westphal nucleus is a small parasympathetic motor nucleus in the midbrain and one of the two nuclei for the oculomotor nerve. It is one of the cranial nerve nuclei. Gross Anatomy The nucleus is located in the central midbrain at the level of the superior colliculus ventral and medi...
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Efface

Efface is a term frequently used by radiologists, most often in the context of CSF-containing spaces in the brain (sulci and ventricles). Unfortunately, it is often used incorrectly.  The word efface, in general English usage, means to cause something to fade or disappear 1,2. In the context o...
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Elevated prolactin (differential)

Elevated prolactin can be due to a number of causes, including elevated production/secretion as well as reduced inhibition.  Prolactin is controlled by numerous homeostatic mechanisms, with tonic secretion of prolactin inhibitory hormone (dopamine) by the hypothalamus having a dominant effect 1...
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Eloquent cortex

Eloquent cortex is a term that refers to specific brain areas that directly controls function, thus damage to these areas generally produces major focal neurological deficits. Examples of eloquent cortex are:  primary motor cortex (precentral gyrus) primary somatosensory cortex (postcentral gy...
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Elster's rule (pituitary gland)

Elster's rule provides a guide to the expected approximate pituitary gland height in relation to age 1. The rule follows an even-numbered pattern of 6, 8, 10, and 12 1: 6 mm pituitary gland height in infants and children 8 mm pituitary gland height in men and postmenopausal women 10 mm pituit...
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Embryonal tumors with multilayered rosettes (ETMR)

Embryonal tumors with multilayered rosettes (ETMR) are rare small round blue cell tumor of the central nervous system and are one of the most aggressive brain tumors usually encountered in children.  Terminology Previously embryonal tumors with multilayered rosettes (ETMR) were known as embryo...
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Emergency CT head (mnemonic)

A useful mnemonic which is used to read an emergency head CT scan is: Blood Can Be Very Bad Mnemonic Using a systematic approach will help to ensure that significant neuropathology will not be missed. B: blood look for epidural hematoma, subdural hematoma, intraparenchymal hemorrhage, intra...
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Emery-Dreiffus muscular dystrophy

Emery-Dreifuss muscular dystrophy is a rare muscular dystrophy characterized by childhood onset of contractures, humeroperoneal muscle atrophy, and cardiac conduction abnormalities.  Clinical course Weakness is slowly progressive, but there is a broad spectrum of clinical severity.  Pathology...
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Emissary veins

Emissary veins (also known as the vena emissaria) are veins which pass through foramina in the skull to provide a venous communication between the dural venous sinuses and veins of the scalp or veins inferior to the skull base (cranial-cerebral anastomosis). They are thin-walled and valveless. ...
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Empty delta sign (dural venous sinus thrombosis)

The empty delta sign is a CT sign of dural venous sinus thrombosis of the superior sagittal sinus, where contrast outlines a triangular filling defect, which represents thrombus. It is only described with CECT-scan or MRI, not with NECT nor non-contrast MRI. An equivalent appearance can be note...
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Empty light bulb sign (brain death)

In brain death, on Tc-99m HMPAO imaging there is absent or reduced flow in the internal carotid arteries and increased flow within the external carotid arteries. This leads to absent uptake in the brain with subsequent increased perfusion in the nasal region. This appearance has been called the ...
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Empty sella

An empty sella, also known as an empty pituitary fossa, is a relatively common incidental finding and posed more of a diagnostic problem before modern cross-sectional imaging. In addition to being incidental, a well-established association with idiopathic intracranial hypertension is also recogn...
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Empty thecal sac sign

The empty thecal sac sign or empty sac sign is when the thecal sac appears empty on MRI of the lumbar spine, best seen on T2-weighted images. If the empty thecal sac sign is present, a diagnosis of adhesive arachnoiditis can be made.​ Radiographic features MRI There is usually no gadolinium c...
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Empyema

Empyemas are purulent inflammatory collections within a body cavity. Contrast this with abscesses, which arise within parenchymal tissue, rather than occupying a pre-existing anatomical space. Terminology Colloquially, the standalone term empyema is used to refer to thoracic empyemas but there...
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Encephalitis due to herpesvirus family

Although sporadic viral encephalitis is most commonly due to herpes simplex virus 1 (HSV-1) the extended herpesvirus family consists of many other viruses many of which can also infect the central nervous system. Encephalitis due to herpesvirus family include 1:   herpes simplex virus 1 (HSV-1)...
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Encephalitis lethargica

Encephalitis lethargica, also known as von Economo encephalitis, is a rare disease of unknown etiology that affects the midbrain and basal ganglia.  Clinical presentation Symptoms are initially that of pharyngitis followed by lethargy, extrapyramidal movements (parkinsonism and dyskinesias), n...
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Encephalocele

Encephalocele, also known as meningoencephalocele, is a form of neural tube defect and a type of cephalocele where brain tissue and overlying meninges herniate out through a defect in the cranium.  Terminology It should be distinguished from cranial meningocele in which the lesion contains onl...
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Encephalocraniocutaneous lipomatosis

Encephalocraniocutaneous lipomatosis (ECCL), also known as Haberland syndrome, is a rare congenital neurocutaneous syndrome characterized by unilateral lipomas of the cranium, face, and neck, ipsilateral lipodermoids of the eye, and ipsilateral brain anomalies. The clinical features of ECCL ove...
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Encephaloduroarteriomyosynangiosis

Encephaloduroarteriomyosynangiosis (EDAMS) is a surgical procedure performed most commonly in children with moyamoya disease or less commonly in individuals with intracranial atherosclerotic disease (ICAD) as a form of indirect revascularization to bypass the occlusive terminal internal carotid ...
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Encephaloduroarteriosynangiosis

Encephaloduroarteriosynangiosis (EDAS) is a surgical procedure performed most commonly in children with moyamoya disease or less commonly in individuals with intracranial atherosclerotic disease (ICAD) as a form of indirect revascularization to bypass the occlusive terminal internal carotid and/...
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Encephalomalacia

Encephalomalacia is term given to describe softening or loss of brain parenchyma with or without surrounding gliosis, as a late manifestation of injury.  Clinical presentation asymptomatic  serve as a focus of seizure Pathology Encephalomalacia is the end result of liquefactive necrosis of ...
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Encephalomyosynangiosis

Encephalomyosynangiosis (EMS) is a surgical procedure performed most commonly in children with moyamoya disease as a form of indirect revascularization to bypass the occlusive terminal internal carotid and/or circle of Willis vessels 1.  It entails dissecting strips of vascularized temporalis m...
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Endolymphatic sac tumor

Endolymphatic sac tumors are very rare, locally invasive tumors of endolymphatic sac. Early detection of these tumors is critical, because early surgical intervention may prevent further hearing loss. Endolymphatic sac tumors do not metastasize but are highly locally aggressive.  Epidemiology ...
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Endosaccular flow disruption devices

Endosaccular flow disruption devices, also simply known as flow disruptors, are used for the treatment of saccular, wide-neck, and usually bifurcation intracranial aneurysms. Their primary function is to stop blood from flowing into the aneurysm, allowing time for the aneurysm to heal. They are ...
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Endovascular clot retrieval (ECR)

Endovascular clot retrieval (ECR) is increasingly performed in patients with presenting with emergent large vessel occlusion (ELVO), especially those with a large ischemic penumbra that is likely to go to ischemic stroke. To be successful, careful patient selection and dedicated training and equ...
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Enlarged posterior fossa 'CSF' space

An enlarged posterior fossa 'CSF' space posterior to the cerebellum has a number of differentials that include: mega cisterna magna epidermoid cyst arachnoid cyst Careful attention to the cerebellum needs to paid as also to be considered are: cerebellar atrophy Dandy-Walker malformations ...
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Enlarged sella turcica (differential)

Enlargement of sella turcica can be seen in situations including the following: empty sella syndrome slight globular enlargement of the sella with no erosion, destruction or posterior displacement of dorsum sellae intracranial hypertension enlargement with erosion of anterior cortex of dorsu...
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En plaque meningioma

En plaque meningiomas refer to a specific meningioma macroscopic appearance characterized by diffuse and extensive dural involvement, usually with extracranial extension into calvarium, orbit, and soft tissues. These tumors are thought to have a collar-like or sheet-like growth along the dura ma...
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Enterovirus 71

Enterovirus 71 is one of the viruses that causes hand-foot-and-mouth disease in children. It is an enterovirus, one of the picornaviruses. Infection with enterovirus 71 predominantly results in a vesicular rash of the hands and feet that follows a prodrome of symptoms including fever, vomiting ...
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Enterovirus rhombencephalitis

Enterovirus rhombencephalitis is the most common neurological complication of enterovirus infection 1. Clinical presentation Enterovirus rhombencephalitis causes acute and severe neurologic disorders such as ataxia, nystagmus, oculomotor palsies, or bulbar palsy. In some cases, neurologic affe...
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Entorhinal cortex

The entorhinal cortex (plural: cortices) (a.k.a. Brodmann area 28) is located in the mesial temporal lobe and acts as the interface between the hippocampus and the neocortex. It has been considered part of the hippocampal formation (along with Ammon’s horn, subiculum and presubiculum), but is di...
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Eosinophilia myalgia syndrome

Eosinophilia myalgia syndrome (EMS) is a fatal neurological condition caused by ingestion of improperly manufactured L-tryptophan. Impurities and/or metabolites that block histamine degradation result in peripheral blood eosinophilia and myalgia.  In the brain, cortical and basal ganglia atroph...
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Ependymal cells

Ependymal cells are one of the four main types of glial cells, and themselves encompass three types of cells 1:  ependymocytes: line the ventricles of the brain and central canal of the spinal cord tanycytes: line the floor of the third ventricle overlying the median eminence of the hypothalam...
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Ependymal cyst

Ependymal cysts are rare benign neuroepithelial cysts lined by ependymal cells. Most are small and asymptomatic and only cause symptoms if large. On imaging, these cysts are essentially indistinguishable from other intraventricular simple cysts (e.g. intraventricular arachnoid cysts). Epidemio...
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Ependymal dot-dash sign

The ependymal dot-dash sign has been described as an early MRI imaging feature of multiple sclerosis before other more florid white matter changes (e.g. Dawson's fingers) become evident 1. It has also been suggested as a feature that can be used to distinguish multiple sclerosis from neuromyelit...
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Ependymal rosettes (ependymoma)

Ependymal rosettes correspond to a histologic architectural pattern that very characteristic of ependymomas, as tumor cells form structures similar to the lining of normal ventricles. They are characterized by a halo or spoke-wheel arrangement of tumor cells surrounding an empty central tubule l...
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Ependymitis granularis

Ependymitis granularis sounds far more worrying than it actually is. The term refers to symmetrical foci of periventricular high T2 and FLAIR signal hyperintensity anterior and lateral to the frontal horns. It is just an anatomical variant, usually small, less than 1 cm, and has a triangular mor...
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Ependymocytes

Ependymocytes are one of the three types of ependymal cells, which in turn are one of the four principles types of glial cells, and are found lining the ventricular system of the brain and the central canal of the spinal cord 1.  They do not form a water-tight barrier between the cerebrospinal ...
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Ependymoma

Ependymomas represent a relatively broad group of glial tumors most often arising from the lining the ventricles of the brain or the central canal of the spinal cord. They account for ~5% of all neuroepithelial neoplasms, ~10% of all pediatric brain tumors and up to 33% of brain tumors occurring...
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Ependymoma RELA fusion-positive

Ependymoma RELA fusion-positive is a recently accepted molecular variant of ependymoma, only recognized in the 2016 update to the WHO classification of CNS tumors. They are the most common type of supratentorial ependymoma in children, and not found in the posterior fossa or spinal cord.  Epide...
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Ependymoma vs astrocytoma of the spinal cord

A number of factors are useful when differentiating between spinal cord ependymoma and spinal cord astrocytoma.  Ependymoma child or adult more central in location bone remodeling is common low T1 signal well-defined enhancement syrinx is more common hemorrhage is more common Astrocytom...
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Epidermoid cyst

Epidermoid cysts are nonneoplastic inclusion cysts derived from ectoderm that are lined solely by squamous epithelium. These are discussed separately by anatomic location: epidermal inclusion cyst intracranial epidermoid cyst splenic epidermoid cyst spinal epidermoid cyst testicular epiderm...
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Epidural angiolipoma

Epidural angiolipomas are rare benign tumors composed of mature adipocytes and abnormal vessels.  Epidemiology Epidural angiolipomas are more frequently encountered in women, and typically in middle age (40-50 years of age) 1.  Clinical presentation In keeping with the slow growth of these t...
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Epidural blood patch

Epidural blood patch is a treatment option for patients with craniospinal hypotension or post-lumbar puncture headaches. The procedure can be done blind or under fluoroscopic or CT guidance, and is performed predominantly by radiologists and anesthesiologists.  Indications craniospinal hypoten...
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Epidural ligaments

The epidural ligaments, also known as meningovertebral ligaments, are variably thick bands of connective tissue located within the spinal epidural space attaching the outer surface of the theca to the inner borders of the spinal canal (vertebrae and ligaments).  They are somewhat variable in nu...
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Epidural lipomatosis

Epidural lipomatosis refers to an excessive accumulation of fat within the spinal epidural space resulting in compression of the thecal sac. In severe cases, compression may be symptomatic. The lumbar region is most frequently affected. Epidemiology The demographics of affected individuals ref...

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